The present review not only devotes on the environmental consequences of plastic bag wastes and other industrial wastes observable in the landfills,in the oceans or elsewhere but also gives a new insight idea on conve...The present review not only devotes on the environmental consequences of plastic bag wastes and other industrial wastes observable in the landfills,in the oceans or elsewhere but also gives a new insight idea on conversion of them into worth material,carbon,for the best electrochemical supercapacitor.Transformation of plastic wastes into high-value materials is the incentive for plastic recycling,end-oflife handling case for plastic bag wastes in practice quite limited.The plastic recycling waste for reuse saves energy compared with manufacturing virgin materials.Herein,we identified several synthetic methods to convert plastic waste and other industrial wastes into carbon material for supercapacitor.Different kinds of carbon materials,including nanofiber,nanotube,graphene,mesoporous carbon,etc.,have been derived from plastic waste,and thus give a superior potential for transforming trash into a"gold capacitor".Finally,conclusions and future trends of high-voltage supercapacitors were made as well as the easy and mass production of high-performance electrode materials for supercapacitors.Our work offers a promising sustainable approach to handle plastic bags,waste,and other industrial wastes and provides a new avenue in supercapacitor applications and other areas.展开更多
In order to mitigate the environmental impact of polyethylene terephthalate(PET)plastic pollution and enhance waste resource utilization;we developed a novel Ir-ReO_(x)/SiO_(2)+HZSM-5 catalytic system for the hydrodeo...In order to mitigate the environmental impact of polyethylene terephthalate(PET)plastic pollution and enhance waste resource utilization;we developed a novel Ir-ReO_(x)/SiO_(2)+HZSM-5 catalytic system for the hydrodeoxygenation(HDO)of PET plastic wastes into cycloalkanes;particularly 1;4-dimethylcyclohexane(DMCH).Under mild conditions(190℃;3 MPa H_(2))with a certain amount of water in cyclopentane solvent;the highest yield of DMCH reached 95.8%;contributing to an overall yield of cycloalkanes at 98.4%within a reaction time of 4 h from HDO of virgin PET.The HDO of PET into DMCH involved initial hydrogenation of PET aromatic ring;then depolymerized by direct hydrogenolysis of acyl C-O bond in the ester group and subsequent cascade HDO of alcoholic C-O bond to saturated ester and alcohol intermediates;and further HDO of these oxygenates converting into desired DMCH product.The Ir-ReO_(x)/SiO_(2) catalyst exhibits fully reduced metallic Ir nanoparticles along with partially reduced ReO_(x) species that are highly dispersed on both SiO_(2) surface and Ir nanoparticle surfaces.The oxophilic nature of ReO_(x) species facilitates the activation of C-O bonds;the acidic HZSM-5 zeolite for the promotion of dehydration reaction;and the protic property of H_(2)O for the enhancement of hydrogenation PET contributed to highly HDO activity of this system.Furthermore;the catalytic system is applicable for the HDO of diverse real-world PET plastic wastes including Coca-ColaTM bottles;green Sprite bottles and white and red discarded fiber cloths;generating DMCH with a yield of up to 95.9%and cycloalkanes with a yield of up to 99.5%.This innovative process presents a new avenue for efficient hydrodeoxygenation conversion of PET into easily separable DMCH which serves as a crucial building block for the production of terephthalic acid to realize the chemical recycling of PET plastic wastes towards a green circular economy.展开更多
Waste or treasure.Plastics,derived from fossil fuels,have revolutionized modern life by providing convenience and benefits across various industries,including packaging,housing,biomedicine,and automotive.Since their c...Waste or treasure.Plastics,derived from fossil fuels,have revolutionized modern life by providing convenience and benefits across various industries,including packaging,housing,biomedicine,and automotive.Since their commercialization in the 1930s and 1940s[1],over 7 billion tons of plastics have been produced,with an annual output exceeding 380 million tons[2].Unfortunately,less than 10%of post-consumer plastics are recycled,and a large portion ends up in landfills or is incinerated,contributing to environmental pollution.展开更多
Nowadays,plastic wastes have seriously endangered human health and ecological safety.Recycling plastics is a promising approach to achieve multiple uses of carbon resources.In this review,photocatalysis is introduced ...Nowadays,plastic wastes have seriously endangered human health and ecological safety.Recycling plastics is a promising approach to achieve multiple uses of carbon resources.In this review,photocatalysis is introduced for the conversion of plastics into various valuable chemicals.The state-of-the-art photocatalytic techniques for plastic conversion are divided into two categories:direct and indirect photoconversion.We summarize in detail the photocatalytic small organic molecules conversion from polyethylene terephthalate,polylactic acid and polyethylene through the alkaline-assistant and hydrothermal pretreatments.Then,we overview the effective strategies of direct photoconverting polyethylene,polylactic acid and polyvinyl chloride into chemicals via the two-step process,amination strategy,and single reactive oxygen species-assistant strategy.Finally,we present some outlook on the current challenges and propose some potential solutions in the future.展开更多
Among the separation techniques used in industry,the triboelectric separation of insulating particles using rotary tube is an efficient technology employed in waste recovery and mineral industries.This process,also ca...Among the separation techniques used in industry,the triboelectric separation of insulating particles using rotary tube is an efficient technology employed in waste recovery and mineral industries.This process,also called free-fall triboelectric separation,is widely used for the sorting and the purification of granular materials resulting from industrial plastic wastes.This paper aims at the achievement of a comprehensive description of a laboratory triboelectric separator built up by the authors and its utilization for an experimental study carried out on granular samples containing particles of polyvinyl chloride(PVC)and polyethylene(PE).Thus,among the variable factors of the process,we analyzed the influence of the most important ones,i.e.,the rotational speed of the cylinder n(rpm),the applied high voltage U(kV),the charging time of the particles t(s),the mass of the sample m(g),and the composition percentage of the sample Cp(%).展开更多
The recycling of plastics is a significant global concern.Due to the thermosetting properties of melamineformaldehyde(MF)resin plastics,which make heating and melting difficult,their recycling and reuse pose substanti...The recycling of plastics is a significant global concern.Due to the thermosetting properties of melamineformaldehyde(MF)resin plastics,which make heating and melting difficult,their recycling and reuse pose substantial challenges.In this study,we developed nitrogen-doped(N-doped)carbon materials through scalable carbonization of MF resin plastic waste.This metal-free N-doped carbon catalyst achieved a hydrogen peroxide(H_(2)O_(2))production rate of 971.6 mmol gcatalyst^(-1)h^(-1)with a Faradaic efficiency for H_(2)O_(2)(FEH_(2)O_(2))exceeding 90%under acidic conditions.Additionally,a flow cell utilizing this carbon catalyst demonstrated a production rate of 11.3 mol cm^(-2)h^(-1)(22.5 mol g_(catalyst)^(-1)h^(-1))and maintained a record-high current density of approximately 530 mA cm^(-2)over 300 h.In-situ electrochemical surface-enhanced Raman spectroscopy and density functional theory calculations revealed the presence of porphyrin-like carbon defects,which serve as active sites for the continuous and stable generation of^(*)OOH species.The nitrogen-doped carbon materials obtained from large-scale carbonization of MF plastic waste exhibit abundant active sites,making them highly promising electrocatalysts for the two-electron oxygen reduction reaction(2e^(-)ORR).展开更多
The past several decades witnessed tremendous success in controlling global plastic pollution,but most of these achievements do not involve recycling the plastic waste.Herein,we propose a recycling strategy of using p...The past several decades witnessed tremendous success in controlling global plastic pollution,but most of these achievements do not involve recycling the plastic waste.Herein,we propose a recycling strategy of using polyvinyl chloride(PVC) wastes to remove copper ions(Cu_(2+)) from electroplating wastewater for microbial control during wound healing and food preservation.The PVC wastes were recovered and crosslinked by the assistance of diethylenetriamine(DETA),which offered multiple active sites to extract Cu_(2+)ions from electroplating wastewater and in situ reduce to copper nanoparticles(CuNPs) containing crystalline Cu and Cu_(2)O.The obtained composites(i.e.,PVC-DETA@CuNPs) performed excellent antibacterial efficacies(99.999%) against Escherichia coli(E.coli) by disrupting bacterial cell membranes through contact-killing action and oxidative stress.After a series of biological evaluations on wound mice,PVC-DETA@-CuNPs exhibited promising potential in resisting wound bacterial infection,accelerating the healing process,and promoting epithelial regeneration.Interestingly,PVCDETA@CuNPs film was evidenced to delay the spoilage process of strawberries and extend their shelf life by combating with food-borne pathogens.This study presents a recycling approach towards waste reuse and the development of innovative antibacterial materials for microbial control.展开更多
Conventional bioplastic production from seaweed often relies on extraction processes that are costly,time-consuming,and yield limited product.This study presents a direct fabrication method using Gracilaria sp.,a red ...Conventional bioplastic production from seaweed often relies on extraction processes that are costly,time-consuming,and yield limited product.This study presents a direct fabrication method using Gracilaria sp.,a red seaweed rich in polysaccharides,to produce bioplastic films without the need for extraction.Sorbitol was incorporated as a plasticizer at concentrations of 0%–10%(w/w)to modify film characteristics.Thermal analysis revealed improved stability at moderate sorbitol levels(5%–7%),while excessive plasticizer slightly reduced thermal resistance.Mechanical testing showed that sorbitol increased film flexibility and elongation at break,though tensile strength and stiffness declined.Tear strength followed a non-linear trend,with improvement observed at higher sorbitol concentrations.Seal strength also increased,peaking at 7%,indicating stronger interfacial bonding between film layers.Biodegradation tests demonstrated accelerated decomposition with increased sorbitol content,achieving complete degradation within 30 days at 10% concentration.Color analysis showed increased brightness and reduced yellowing,enhancing the visual quality of the films.These results confirm that direct conversion of bioplastic is both feasible and effective.Sorbitol plays a key role in tuning film properties,offering a low-cost,scalable pathway to biodegradable materials suitable for environmentally friendly packaging applications.展开更多
Current ever-accumulating plastic waste can be considered a significant carbon resource for energy conversion and chemical production.The development of new approaches for upcycling plastic waste through chemical degr...Current ever-accumulating plastic waste can be considered a significant carbon resource for energy conversion and chemical production.The development of new approaches for upcycling plastic waste through chemical degradation may enable circularity and promote closed-loop recycling of carbon sources compared to traditional recycling methods.Zeolite,a widely used solid acid catalyst with high industrial potential in petroleum and biomass refining,has been extensively studied for its role in transforming plastics.In this review,we present an overview of zeolite-based catalytic systems for the chemical recycling of plastic waste and discuss how zeolites could potentially contribute to the future development of a circular economy.To provide a comprehensive understanding,we begin with a brief introduction to zeolites,analyzing their key features and exploring their opportunities as well as challenges in processing plastic waste.Subsequently,we delve into the chemistry of catalytic cracking and tandem catalysis using zeolite-based catalysts on plastics.Overall,we emphasize the importance of intelligent catalyst design and lower-energy pathways to incentivize plastic upcycling while alleviating the burden caused by waste plastics.展开更多
The widespread use of plastic waste has caused significant environmental pollution,becoming a focal point of global concern,particularly the challenge of dechlorination in mixed plastic waste.Selective dissolution is ...The widespread use of plastic waste has caused significant environmental pollution,becoming a focal point of global concern,particularly the challenge of dechlorination in mixed plastic waste.Selective dissolution is a promising plastic chemical recycling technology that offers benefits such as simple processes,convenient operation,and recyclable solvents.However,selecting suitable solvents remains a challenge.This study establishes a virtual solvent database containing 530 common inorganic and organic solvents.By calculating theσ-profile of polyvinyl chloride(PVC)and polyethylene(PE)models using quantum mechanical calculations and employing the conductor-like screening model for real solvents(COSMO-RS)method,the solubility performance of these solvents for PVC and PE at different temperatures was predicted.The results demonstrate the high accuracy of the COSMO-RS method in predicting solubility.By comparing the solubility differences between PVC and PE in different solvents,a series of solvents suitable for selectively removing PVC from mixed plastics were identified,for example,N-methyl-2-pyrrolidone(NMP),dimethyl sulfoxide(DMSO),tetrahydrofuran(THF),and N,Ndimethylacetamide(DMAc).This method provides a novel solution to the solvent selection challenge in plastic chemical recycling,potentially shortening the research and development period,reducing experimental costs,and promoting the development of green and refined waste plastic recycling processes.展开更多
Electrocatalysis offers efficient and targeted conversion of monomers derived from waste polyester plastics to chemical products under ambient temperature and pressure conditions.This review provides analysis of resea...Electrocatalysis offers efficient and targeted conversion of monomers derived from waste polyester plastics to chemical products under ambient temperature and pressure conditions.This review provides analysis of research on electrochemical upgrading of monomers derived from waste polyester plastics published from2021 to present.Factors for assessing upgrading of waste polyester plastics include alkaline hydrolysis pretreatment,indices of electrochemical reaction process(activity,stability,and techno-economic a nalysis),separation,and product recovery.Types of depolymerization monomers and their value-added products are summarized along with electrocatalytic mechanisms and reaction pathways.Notably,cathode coupled reactions offer significant value for anodic waste plastic oxidation during electrolysis processes.Development of bifunctional electrocatalysts can reduce the cost of coupled systems and complexity of the electrolyzer.Upgrading and recycling of waste plastic monomers using electrocatalytic technology should undergo downstream processing to form high-value products containing C-N and C-S derived functional groups obtained from depolymerized monomers,Electrochemical conversion and upgrading of monomers derived from waste polyester plastics can contribute to industrialization and global economies and help to realize environmental sustainability.展开更多
This research examined the feasibility of incorporating electric arc furnace(EAF)slag and waste plastic into stone matrix asphalt(SMA)mixtures.With annual global production of over 70 million tons of EAF slag and 300 ...This research examined the feasibility of incorporating electric arc furnace(EAF)slag and waste plastic into stone matrix asphalt(SMA)mixtures.With annual global production of over 70 million tons of EAF slag and 300 million tons of plastic waste,repurposing these materials could yield substantial environmental benefits.The research evaluated SMA mixtures with EAF slag as aggregate replacement and waste plastic as a binder modifier.The research aimed to develop sustainable SMA formulations while promoting recycling of industrial byproducts.Laboratory experiments were conducted to evaluate mix design characteristics,drain-down potential,abrasion resistance,rutting resistance,moisture susceptibility,fatigue performance,and stiffness of modified SMA mixtures.The addition of waste plastic,ranging from 4%,6%,8%and 12%by weight of bitumen,demonstrated significant improvements in key properties.Results showed that waste plastic reduced the optimum binder content and increased voids in the mineral aggregate.EAF slag mixtures demonstrated improved drain-down characteristics and moisture susceptibility.Both rutting resistance and fatigue life increased significantly with waste plastic content,with EAF slag mixtures consistently outperforming those made with conventional aggregates.Ultrasonic pulse velocity tests indicated higher stiffness in modified mixtures.The optimal waste plastic content was determined to be 8%by weight of bitumen.Statistical analysis confirmed significant effects of both EAF slag and waste plastic on multiple performance parameters.These findings highlight the potential of incorporating industrial byproducts into SMA mixtures to achieve high-performance road construction solutions,offering a viable pathway for addressing global waste management challenges.展开更多
Developing energy-efficient nitrite-to-ammonia(NO_(2)RR)conversion technologies while simultaneously enabling the electrochemical upcycling of waste polyethylene terephthalate(PET)plastics into highvalue-added chemica...Developing energy-efficient nitrite-to-ammonia(NO_(2)RR)conversion technologies while simultaneously enabling the electrochemical upcycling of waste polyethylene terephthalate(PET)plastics into highvalue-added chemicals is of great significance.Herein,an atomic oxygen vacancy(V_(o))engineering is developed to optimize the catalytic performance of V_(o2)-Co(OH)F nanoarray towards the NO_(2)RR and PET-derived ethylene glycol oxidation reaction(EGOR).The optimal V_(o2)-Co(OH)F achieves an ultralow operating potential of -0.03 V vs.RHE at -100 mA cm^(-2)and a remarkable NH_(3)Faradaic efficiency(FE)of 98.4% at -0.2 V vs.RHE for NO_(2)RR,and a high formate FE of 98.03% for EGOR.Operando spectroscopic analysis and theoretical calculations revealed that oxygen vacancies play a crucial role in optimizing the electronic structure of V_(o2)-Co(OH)F,modulating the adsorption free energies of key reaction intermediates,and lowering the reaction energy barrier,thereby enhancing its overall catalytic performance.Remarkably,the V_(o2)-Co(OH)F-based NO_(2)RR||EGOR electrolyzer realized high NH_(3)and formate yield rates of 33.9 and 44.9 mg h^(-1)cm^(-2)at 1.7 V,respectively,while demonstrating outstanding long-term stability over 100 h.This work provides valuable insights into the rational design of advanced electrocatalysts for co-electrolysis systems.展开更多
The development of catalysts that can efficiently separate both bulk and interface charges is crucial for conversion and utilization of solar energy.In this study,a homo-heterojunction was fabricated by combin-ing twi...The development of catalysts that can efficiently separate both bulk and interface charges is crucial for conversion and utilization of solar energy.In this study,a homo-heterojunction was fabricated by combin-ing twinned-Cd_(0.5)Zn_(0.5)S(T-CZS)and Ni_(3)(PO_(4))_(2)with crystalline water(NiPO)using a solvent evaporation strategy for efficient photocatalytic H_(2)evolution in water containing degradable plastics.The bulk phase of T-CZS consists of wurtzite Cd_(0.5)Zn_(0.5)S(WZ-CZS)and zinc blende Cd_(0.5)Zn_(0.5)S(ZB-CZS),they exhibit a slight difference in energy range and can form S-scheme homojunction,while NiPO and T-CZS constitute the S-scheme heterojunction,they work together to promote the separation of bulk and interface charges.This double S-scheme homo-heterojunction achieves a hydrogen evolution rate(rH_(2))of 73.2 mmol h−1 g−1 over 8%NiPO/T-CZS in a solution mainly composed of polylactic acid(PLA),which exhibits an in-crease by factors of 243.0 and 4.5 compared to NiPO and T-CZS individually.Meanwhile,PLA plastics are degraded into organic chemicals including formic acid,acetic acid,and pyruvic acid.Moreover,NiPO ex-hibits(localized surface plasmon resonance)LSPR effect,which can broaden the light absorption range of the system,reduce the H_(2)evolution overpotential,and enhance electron utilization efficiency.Based on electron capture experiments and band theory analysis,the introducing of plastic as an electron donor further accelerates the evolution process of H_(2),while alkaline sodium hydroxide(NaOH)solution pro-motes the PLA dissociation and enhances oxidation driving force,indirectly promoting the H_(2)evolution kinetics of this system.The present research offers prospective solutions for engineering solar-powered H_(2)evolution to tackle energy challenges.展开更多
The pyrolysis of different waste polymers （polyethylene, polypropylene and polystyrene） was investigated in a tube reactor at 550 ℃ in the absence of oxygen. Additionally the energetic utilization of products have ...The pyrolysis of different waste polymers （polyethylene, polypropylene and polystyrene） was investigated in a tube reactor at 550 ℃ in the absence of oxygen. Additionally the energetic utilization of products have also been followed both in refining and petrochemical industry. Pyrolysis products were separated into fractions of gases, naphtha, middle distillates and heavy oil. Raw materials have been collected both from industrial and household sources： polyethylene from agriculture, polyethylene from packaging and polystyrene from packaging and electronic equipments. Yields and properties of volatile products have changed by the raw materials. Products have been analyzed by gas chromatography. Fourier transformed infrared spectroscopy, size exclusion chromatography and other standardized methods. Naphtha had high octane numbers （80 〈 RON）, while high cetane numbers （〉 75） in case of middle distillates. Moreover fractions contained approximately half of unsaturated hydrocarbons, mainly α-olefins, but the percentage was depending on the raw materials. These properties are advantageous for fuel-like applications.展开更多
In this paper,a simple method to plate a hydrophobic coating on the inner surface of a small-scaled tube was proposed,where the coating consisted of carbon microspheres.Three common plastics polystyrene,polycarbonate ...In this paper,a simple method to plate a hydrophobic coating on the inner surface of a small-scaled tube was proposed,where the coating consisted of carbon microspheres.Three common plastics polystyrene,polycarbonate and polyethylene were used as the feedstocks to be processed in supercritical water in a quartz tubular reactor.After reaction,the contact angle of droplet on the inner surface of the quartz tube was turned out to be over 100°,significantly larger than that of the blank tube 54°.When processing polystyrene in the 750℃ supercritical water for 10 min,the largest contact angle was obtained,up to 145°.Besides,in this sample,the size of carbon spheres was smallest,about 2.09μm diameter on average.When comparing among different types of plastics under the same condition,the contact angle of surface made from PC took the dominant position over that of PS and PE,124°,100°and 90°,respectively.In the sample made from PC,carbon spheres adhered into a mountainlike shape,producing a binary geometric structure.Furthermore,this research could be helpful in the discussion of plastic waste management and carbon spheres fabrication with low cost.展开更多
New route of the utilization of products obtained by waste plastic pyrolysis has been investigated. ct-olefin-succinic-anhydride intermediate based on new experimental additives has been developed and used for achievi...New route of the utilization of products obtained by waste plastic pyrolysis has been investigated. ct-olefin-succinic-anhydride intermediate based on new experimental additives has been developed and used for achieving the better properties of carbon fibre reinforced polymer composites. Hydrocarbon fractions were produced by the pure thermal pyrolysis of waste polymers in a tube reactor using 550 ℃ in the absence of oxygen. Selected compounds （C30-C50） from pyrolysis products have been used as raw materials in the additive synthesis step. Polymer composite specimens have been investigated among others by universal tensile machine, SEM （scanning electron microscopy） and FTIR （fourier transformed infrared spectroscopy） methods. The tensile strength could be increased by 29.9%, the E-modulus by 24.2% and the Charpy impact strength by 13.3% in the presence of the experimental additive. Fibre-matrix interaction has been studied on SEM micrographs of the fractured face of composites. The results of mechanical testes have been supported by the SEM micrographs and possible shames of the coupling have been proposed.展开更多
Marine plastic debris has been a pervasive issue since the last century, and research on its sources and fates plays a vital role in the establishment of mitigation measures. However, data on the quantity of plastic w...Marine plastic debris has been a pervasive issue since the last century, and research on its sources and fates plays a vital role in the establishment of mitigation measures. However, data on the quantity of plastic waste that enters the sea on a certain timescale remain largely unavailable in China. Here, we established a model using material flow analysis method based on life cycle assessment to follow plastic product from primary plastic to plastic waste with statistical data and monitoring data from accurate sources. This model can be used to estimate and forecast the annual input of plastic waste into the sea from China until 2020. In 2011, 0.547 3-0.751 5 million tons of plastic waste entered the seas in China, with a growth rate of 4.55% per year until 2017. And the amount will decrease to 0.257 1 to 0.353 1 million tons in 2020 under the influence of governmental management. The amount of plastic waste discharged from coastal areas calculated in this study was much larger than that from river, thus it is suggested to strengthen the governance and control of plastic waste in coastal fishery activities in China in order to reduce the amount of marine plastic waste input.展开更多
PM_(1)0 samples were collected from an urban/industrial site nearby Athens,where uncontrolled burning activities occur.PAHs,monocarboxylic,dicarboxylic,hydroxycarboxylic and aromatic acids,tracers from BVOC oxidation,...PM_(1)0 samples were collected from an urban/industrial site nearby Athens,where uncontrolled burning activities occur.PAHs,monocarboxylic,dicarboxylic,hydroxycarboxylic and aromatic acids,tracers from BVOC oxidation,biomass burning tracers and bisphenol A were determined.PAH,monocarboxylic acids,biomass burning tracers and bisphenol A were increased during autumn/winter,while BSOA tracers,dicarboxylic-and hydroxycarboxylic acids during summer.Regarding aromatic acids,different sources and formation mechanisms were indicated as benzoic,phthalic and trimellitic acids were peaked during summer whereas p-toluic,isophthalic and terephthalic were more abundant during autumn/winter.The Benzo[a]pyrene-equivalent carcinogenic power,carcinogenic and mutagenic activities were calculated showing significant(p<0.05)increases during the colder months.Palmitic,succinic and malic acids were the most abundant monocarboxylic,dicarboxylic and hydrocarboxylic acids during the entire sampling period.Isoprene oxidation was the most significant contributor to BSOA as the isoprene-SOA compounds were two times more abundant than the pinene-SOA(13.4±12.3 and 6.1±2.9 ng/m^3,respectively).Ozone has significant impact on the formation of many studied compounds showing significant correlations with:isoprene-SOA(r=0.77),hydrocarboxylic acids(r=0.69),pinene-SOA(r=0.63),dicarboxylic acids(r=0.58),and the sum of phthalic,benzoic and trimellitic acids(r=0.44).PCA demonstrated five factors that could explain sources including plastic enriched waste burning(30.8%),oxidation of unsaturated fatty acids(23.0%),vehicle missions and cooking(9.2%),biomass burning(7.7%)and oxidation of VOCs(5.8%).The results highlight the significant contribution of plastic waste uncontrolled burning to the overall air quality degradation.展开更多
Waste plastics mainly come from MSW and usually exist in the form of mixed plastics. During the co-pyrolysis process of mixed plastics, various plastic components have different physicochemical properties and reaction...Waste plastics mainly come from MSW and usually exist in the form of mixed plastics. During the co-pyrolysis process of mixed plastics, various plastic components have different physicochemical properties and reaction mechanisms. Considering the high viscosity and low thermal conductivity of molten plastics, a falling film pyrolysis reactor was selected to explore the rapid co-pyrolysis process of typical plastic components(PP, PE and PS).The oil and gas yields and the compositions of pyrolysis products of the three components under different ratios at pyrolysis temperatures were analyzed to explore the co-pyrolysis characteristics of PP, PE, and PS. The study is of great significance to the recycling of waste plastics.展开更多
基金supported by the National Natural Science Foundation of China(Nos.21975025,21575015,21203008)the Beijing Natural Science Foundation(No.2172051)+1 种基金the National Key Research and Development Program of China"New Energy Project for Electric Vehicle"(No.2016YFB0100204)State Key Laboratory for Modification of Chemical Fibers and Polymers Materials,Donghua University。
文摘The present review not only devotes on the environmental consequences of plastic bag wastes and other industrial wastes observable in the landfills,in the oceans or elsewhere but also gives a new insight idea on conversion of them into worth material,carbon,for the best electrochemical supercapacitor.Transformation of plastic wastes into high-value materials is the incentive for plastic recycling,end-oflife handling case for plastic bag wastes in practice quite limited.The plastic recycling waste for reuse saves energy compared with manufacturing virgin materials.Herein,we identified several synthetic methods to convert plastic waste and other industrial wastes into carbon material for supercapacitor.Different kinds of carbon materials,including nanofiber,nanotube,graphene,mesoporous carbon,etc.,have been derived from plastic waste,and thus give a superior potential for transforming trash into a"gold capacitor".Finally,conclusions and future trends of high-voltage supercapacitors were made as well as the easy and mass production of high-performance electrode materials for supercapacitors.Our work offers a promising sustainable approach to handle plastic bags,waste,and other industrial wastes and provides a new avenue in supercapacitor applications and other areas.
基金supported by the National Natural Science Foundation of China(22208243,52276209).
文摘In order to mitigate the environmental impact of polyethylene terephthalate(PET)plastic pollution and enhance waste resource utilization;we developed a novel Ir-ReO_(x)/SiO_(2)+HZSM-5 catalytic system for the hydrodeoxygenation(HDO)of PET plastic wastes into cycloalkanes;particularly 1;4-dimethylcyclohexane(DMCH).Under mild conditions(190℃;3 MPa H_(2))with a certain amount of water in cyclopentane solvent;the highest yield of DMCH reached 95.8%;contributing to an overall yield of cycloalkanes at 98.4%within a reaction time of 4 h from HDO of virgin PET.The HDO of PET into DMCH involved initial hydrogenation of PET aromatic ring;then depolymerized by direct hydrogenolysis of acyl C-O bond in the ester group and subsequent cascade HDO of alcoholic C-O bond to saturated ester and alcohol intermediates;and further HDO of these oxygenates converting into desired DMCH product.The Ir-ReO_(x)/SiO_(2) catalyst exhibits fully reduced metallic Ir nanoparticles along with partially reduced ReO_(x) species that are highly dispersed on both SiO_(2) surface and Ir nanoparticle surfaces.The oxophilic nature of ReO_(x) species facilitates the activation of C-O bonds;the acidic HZSM-5 zeolite for the promotion of dehydration reaction;and the protic property of H_(2)O for the enhancement of hydrogenation PET contributed to highly HDO activity of this system.Furthermore;the catalytic system is applicable for the HDO of diverse real-world PET plastic wastes including Coca-ColaTM bottles;green Sprite bottles and white and red discarded fiber cloths;generating DMCH with a yield of up to 95.9%and cycloalkanes with a yield of up to 99.5%.This innovative process presents a new avenue for efficient hydrodeoxygenation conversion of PET into easily separable DMCH which serves as a crucial building block for the production of terephthalic acid to realize the chemical recycling of PET plastic wastes towards a green circular economy.
基金supported by the National Key Research and Development Program of China(YFB20234004900)the Shanghai Pilot Program for Basic Research-Shanghai Jiao Tong University(21TQ1400211)+2 种基金the National Natural Science Foundation of China(22109095)the Oceanic Interdisciplinary Program of Shanghai Jiao Tong University(SL2022MS007)the State Key Laboratory of Photoelectric Conversion and Utilization of Solar Energy(Innovation Fund Project SKLPCU24OP009).
文摘Waste or treasure.Plastics,derived from fossil fuels,have revolutionized modern life by providing convenience and benefits across various industries,including packaging,housing,biomedicine,and automotive.Since their commercialization in the 1930s and 1940s[1],over 7 billion tons of plastics have been produced,with an annual output exceeding 380 million tons[2].Unfortunately,less than 10%of post-consumer plastics are recycled,and a large portion ends up in landfills or is incinerated,contributing to environmental pollution.
基金supported by the National Natural Science Foundation of China(42421005,22275178)。
文摘Nowadays,plastic wastes have seriously endangered human health and ecological safety.Recycling plastics is a promising approach to achieve multiple uses of carbon resources.In this review,photocatalysis is introduced for the conversion of plastics into various valuable chemicals.The state-of-the-art photocatalytic techniques for plastic conversion are divided into two categories:direct and indirect photoconversion.We summarize in detail the photocatalytic small organic molecules conversion from polyethylene terephthalate,polylactic acid and polyethylene through the alkaline-assistant and hydrothermal pretreatments.Then,we overview the effective strategies of direct photoconverting polyethylene,polylactic acid and polyvinyl chloride into chemicals via the two-step process,amination strategy,and single reactive oxygen species-assistant strategy.Finally,we present some outlook on the current challenges and propose some potential solutions in the future.
文摘Among the separation techniques used in industry,the triboelectric separation of insulating particles using rotary tube is an efficient technology employed in waste recovery and mineral industries.This process,also called free-fall triboelectric separation,is widely used for the sorting and the purification of granular materials resulting from industrial plastic wastes.This paper aims at the achievement of a comprehensive description of a laboratory triboelectric separator built up by the authors and its utilization for an experimental study carried out on granular samples containing particles of polyvinyl chloride(PVC)and polyethylene(PE).Thus,among the variable factors of the process,we analyzed the influence of the most important ones,i.e.,the rotational speed of the cylinder n(rpm),the applied high voltage U(kV),the charging time of the particles t(s),the mass of the sample m(g),and the composition percentage of the sample Cp(%).
基金supported by the National Natural Science Foundation of China(Grant No.22276123,22025505)the Oceanic Interdisciplinary Program of Shanghai Jiao Tong University(SL2022ZD105)State Key Lab of Metal Matrix Composite。
文摘The recycling of plastics is a significant global concern.Due to the thermosetting properties of melamineformaldehyde(MF)resin plastics,which make heating and melting difficult,their recycling and reuse pose substantial challenges.In this study,we developed nitrogen-doped(N-doped)carbon materials through scalable carbonization of MF resin plastic waste.This metal-free N-doped carbon catalyst achieved a hydrogen peroxide(H_(2)O_(2))production rate of 971.6 mmol gcatalyst^(-1)h^(-1)with a Faradaic efficiency for H_(2)O_(2)(FEH_(2)O_(2))exceeding 90%under acidic conditions.Additionally,a flow cell utilizing this carbon catalyst demonstrated a production rate of 11.3 mol cm^(-2)h^(-1)(22.5 mol g_(catalyst)^(-1)h^(-1))and maintained a record-high current density of approximately 530 mA cm^(-2)over 300 h.In-situ electrochemical surface-enhanced Raman spectroscopy and density functional theory calculations revealed the presence of porphyrin-like carbon defects,which serve as active sites for the continuous and stable generation of^(*)OOH species.The nitrogen-doped carbon materials obtained from large-scale carbonization of MF plastic waste exhibit abundant active sites,making them highly promising electrocatalysts for the two-electron oxygen reduction reaction(2e^(-)ORR).
基金financially supported by the National Energy R&D Center of Petroleum Refining Technology (RIPP,SINOPEC)the National Natural Science Foundation of China (Nos.22062017 and 22164015)+2 种基金the Natural Science Foundation of Inner Mongolia Autonomous Region (Nos.2024ZD10 and 2023QN02011)the Program of Higher-Level Talents of Inner Mongolia University (No.10000-22311201/035)the Research Program of science and technology at Universities of Inner Mongolia Autonomous Region (No.NJZZ23091)
文摘The past several decades witnessed tremendous success in controlling global plastic pollution,but most of these achievements do not involve recycling the plastic waste.Herein,we propose a recycling strategy of using polyvinyl chloride(PVC) wastes to remove copper ions(Cu_(2+)) from electroplating wastewater for microbial control during wound healing and food preservation.The PVC wastes were recovered and crosslinked by the assistance of diethylenetriamine(DETA),which offered multiple active sites to extract Cu_(2+)ions from electroplating wastewater and in situ reduce to copper nanoparticles(CuNPs) containing crystalline Cu and Cu_(2)O.The obtained composites(i.e.,PVC-DETA@CuNPs) performed excellent antibacterial efficacies(99.999%) against Escherichia coli(E.coli) by disrupting bacterial cell membranes through contact-killing action and oxidative stress.After a series of biological evaluations on wound mice,PVC-DETA@-CuNPs exhibited promising potential in resisting wound bacterial infection,accelerating the healing process,and promoting epithelial regeneration.Interestingly,PVCDETA@CuNPs film was evidenced to delay the spoilage process of strawberries and extend their shelf life by combating with food-borne pathogens.This study presents a recycling approach towards waste reuse and the development of innovative antibacterial materials for microbial control.
基金funded by IAEA Coordinated Research Project F22081.
文摘Conventional bioplastic production from seaweed often relies on extraction processes that are costly,time-consuming,and yield limited product.This study presents a direct fabrication method using Gracilaria sp.,a red seaweed rich in polysaccharides,to produce bioplastic films without the need for extraction.Sorbitol was incorporated as a plasticizer at concentrations of 0%–10%(w/w)to modify film characteristics.Thermal analysis revealed improved stability at moderate sorbitol levels(5%–7%),while excessive plasticizer slightly reduced thermal resistance.Mechanical testing showed that sorbitol increased film flexibility and elongation at break,though tensile strength and stiffness declined.Tear strength followed a non-linear trend,with improvement observed at higher sorbitol concentrations.Seal strength also increased,peaking at 7%,indicating stronger interfacial bonding between film layers.Biodegradation tests demonstrated accelerated decomposition with increased sorbitol content,achieving complete degradation within 30 days at 10% concentration.Color analysis showed increased brightness and reduced yellowing,enhancing the visual quality of the films.These results confirm that direct conversion of bioplastic is both feasible and effective.Sorbitol plays a key role in tuning film properties,offering a low-cost,scalable pathway to biodegradable materials suitable for environmentally friendly packaging applications.
文摘Current ever-accumulating plastic waste can be considered a significant carbon resource for energy conversion and chemical production.The development of new approaches for upcycling plastic waste through chemical degradation may enable circularity and promote closed-loop recycling of carbon sources compared to traditional recycling methods.Zeolite,a widely used solid acid catalyst with high industrial potential in petroleum and biomass refining,has been extensively studied for its role in transforming plastics.In this review,we present an overview of zeolite-based catalytic systems for the chemical recycling of plastic waste and discuss how zeolites could potentially contribute to the future development of a circular economy.To provide a comprehensive understanding,we begin with a brief introduction to zeolites,analyzing their key features and exploring their opportunities as well as challenges in processing plastic waste.Subsequently,we delve into the chemistry of catalytic cracking and tandem catalysis using zeolite-based catalysts on plastics.Overall,we emphasize the importance of intelligent catalyst design and lower-energy pathways to incentivize plastic upcycling while alleviating the burden caused by waste plastics.
基金financially supported by SINOPEC Research Institute of Petroleum Processing Co.,Ltd.the National Natural Science Foundation of China(22302220)+2 种基金the Shanxi Province Science Foundation for Youth(202203021222403)Funding support was also received from the Synfuels China Co.,Ltd.the Institute of Coal Chemistry,Chinese Academy of Sciences。
文摘The widespread use of plastic waste has caused significant environmental pollution,becoming a focal point of global concern,particularly the challenge of dechlorination in mixed plastic waste.Selective dissolution is a promising plastic chemical recycling technology that offers benefits such as simple processes,convenient operation,and recyclable solvents.However,selecting suitable solvents remains a challenge.This study establishes a virtual solvent database containing 530 common inorganic and organic solvents.By calculating theσ-profile of polyvinyl chloride(PVC)and polyethylene(PE)models using quantum mechanical calculations and employing the conductor-like screening model for real solvents(COSMO-RS)method,the solubility performance of these solvents for PVC and PE at different temperatures was predicted.The results demonstrate the high accuracy of the COSMO-RS method in predicting solubility.By comparing the solubility differences between PVC and PE in different solvents,a series of solvents suitable for selectively removing PVC from mixed plastics were identified,for example,N-methyl-2-pyrrolidone(NMP),dimethyl sulfoxide(DMSO),tetrahydrofuran(THF),and N,Ndimethylacetamide(DMAc).This method provides a novel solution to the solvent selection challenge in plastic chemical recycling,potentially shortening the research and development period,reducing experimental costs,and promoting the development of green and refined waste plastic recycling processes.
基金financially supported by the National Natural Science Foundation of China(Nos.22178181)the Natural Science Fund of Tianjin(No.21JCZDJC00180)the Fundamental Research Funds for the Central Universities(Nankai University(No.63243129)).
文摘Electrocatalysis offers efficient and targeted conversion of monomers derived from waste polyester plastics to chemical products under ambient temperature and pressure conditions.This review provides analysis of research on electrochemical upgrading of monomers derived from waste polyester plastics published from2021 to present.Factors for assessing upgrading of waste polyester plastics include alkaline hydrolysis pretreatment,indices of electrochemical reaction process(activity,stability,and techno-economic a nalysis),separation,and product recovery.Types of depolymerization monomers and their value-added products are summarized along with electrocatalytic mechanisms and reaction pathways.Notably,cathode coupled reactions offer significant value for anodic waste plastic oxidation during electrolysis processes.Development of bifunctional electrocatalysts can reduce the cost of coupled systems and complexity of the electrolyzer.Upgrading and recycling of waste plastic monomers using electrocatalytic technology should undergo downstream processing to form high-value products containing C-N and C-S derived functional groups obtained from depolymerized monomers,Electrochemical conversion and upgrading of monomers derived from waste polyester plastics can contribute to industrialization and global economies and help to realize environmental sustainability.
文摘This research examined the feasibility of incorporating electric arc furnace(EAF)slag and waste plastic into stone matrix asphalt(SMA)mixtures.With annual global production of over 70 million tons of EAF slag and 300 million tons of plastic waste,repurposing these materials could yield substantial environmental benefits.The research evaluated SMA mixtures with EAF slag as aggregate replacement and waste plastic as a binder modifier.The research aimed to develop sustainable SMA formulations while promoting recycling of industrial byproducts.Laboratory experiments were conducted to evaluate mix design characteristics,drain-down potential,abrasion resistance,rutting resistance,moisture susceptibility,fatigue performance,and stiffness of modified SMA mixtures.The addition of waste plastic,ranging from 4%,6%,8%and 12%by weight of bitumen,demonstrated significant improvements in key properties.Results showed that waste plastic reduced the optimum binder content and increased voids in the mineral aggregate.EAF slag mixtures demonstrated improved drain-down characteristics and moisture susceptibility.Both rutting resistance and fatigue life increased significantly with waste plastic content,with EAF slag mixtures consistently outperforming those made with conventional aggregates.Ultrasonic pulse velocity tests indicated higher stiffness in modified mixtures.The optimal waste plastic content was determined to be 8%by weight of bitumen.Statistical analysis confirmed significant effects of both EAF slag and waste plastic on multiple performance parameters.These findings highlight the potential of incorporating industrial byproducts into SMA mixtures to achieve high-performance road construction solutions,offering a viable pathway for addressing global waste management challenges.
基金financially supported by the National Natural Science Foundation of China(22205205)the Fundamental Research Funds of Zhejiang Sci-Tech University(ZSTU,25262157Y)the staff of beamline BL11B and BL13SSW at Shanghai Synchrotron Radiation Facility for experimental support。
文摘Developing energy-efficient nitrite-to-ammonia(NO_(2)RR)conversion technologies while simultaneously enabling the electrochemical upcycling of waste polyethylene terephthalate(PET)plastics into highvalue-added chemicals is of great significance.Herein,an atomic oxygen vacancy(V_(o))engineering is developed to optimize the catalytic performance of V_(o2)-Co(OH)F nanoarray towards the NO_(2)RR and PET-derived ethylene glycol oxidation reaction(EGOR).The optimal V_(o2)-Co(OH)F achieves an ultralow operating potential of -0.03 V vs.RHE at -100 mA cm^(-2)and a remarkable NH_(3)Faradaic efficiency(FE)of 98.4% at -0.2 V vs.RHE for NO_(2)RR,and a high formate FE of 98.03% for EGOR.Operando spectroscopic analysis and theoretical calculations revealed that oxygen vacancies play a crucial role in optimizing the electronic structure of V_(o2)-Co(OH)F,modulating the adsorption free energies of key reaction intermediates,and lowering the reaction energy barrier,thereby enhancing its overall catalytic performance.Remarkably,the V_(o2)-Co(OH)F-based NO_(2)RR||EGOR electrolyzer realized high NH_(3)and formate yield rates of 33.9 and 44.9 mg h^(-1)cm^(-2)at 1.7 V,respectively,while demonstrating outstanding long-term stability over 100 h.This work provides valuable insights into the rational design of advanced electrocatalysts for co-electrolysis systems.
基金financially supported by The Local Science and Development Fund Project Guided by the Central Govern-ment(No.24ZYQM001)the National Natural Science Foundation of China(Nos.22378326,11974276,and22078261)+6 种基金the Natural Science Basic Research Program of Shaanxi Province(No.2023-JC-YB-115)the Shaanxi Key Science and Technology Innovation Team Project(No.2022TD-33)the Qin Chuangyuan project of Shaanxi Province(No.QCYRCXM2022-213)the Basic Science Re-search Program of Shaanxi Basic Sciences Institute(Chemistry,Bi-ology,No.23JHQ081)the Key Research and Development Program of Shaanxi Province(No.2024GX-YBXM-449)the Initial Scientific Research Fund of Northwest University(S.Tao),Excellent Doctoral Dissertation Cultivation Program at Northwestern University(No.YB2024012)the Program of China Scholarship Council(No.202406970056)。
文摘The development of catalysts that can efficiently separate both bulk and interface charges is crucial for conversion and utilization of solar energy.In this study,a homo-heterojunction was fabricated by combin-ing twinned-Cd_(0.5)Zn_(0.5)S(T-CZS)and Ni_(3)(PO_(4))_(2)with crystalline water(NiPO)using a solvent evaporation strategy for efficient photocatalytic H_(2)evolution in water containing degradable plastics.The bulk phase of T-CZS consists of wurtzite Cd_(0.5)Zn_(0.5)S(WZ-CZS)and zinc blende Cd_(0.5)Zn_(0.5)S(ZB-CZS),they exhibit a slight difference in energy range and can form S-scheme homojunction,while NiPO and T-CZS constitute the S-scheme heterojunction,they work together to promote the separation of bulk and interface charges.This double S-scheme homo-heterojunction achieves a hydrogen evolution rate(rH_(2))of 73.2 mmol h−1 g−1 over 8%NiPO/T-CZS in a solution mainly composed of polylactic acid(PLA),which exhibits an in-crease by factors of 243.0 and 4.5 compared to NiPO and T-CZS individually.Meanwhile,PLA plastics are degraded into organic chemicals including formic acid,acetic acid,and pyruvic acid.Moreover,NiPO ex-hibits(localized surface plasmon resonance)LSPR effect,which can broaden the light absorption range of the system,reduce the H_(2)evolution overpotential,and enhance electron utilization efficiency.Based on electron capture experiments and band theory analysis,the introducing of plastic as an electron donor further accelerates the evolution process of H_(2),while alkaline sodium hydroxide(NaOH)solution pro-motes the PLA dissociation and enhances oxidation driving force,indirectly promoting the H_(2)evolution kinetics of this system.The present research offers prospective solutions for engineering solar-powered H_(2)evolution to tackle energy challenges.
文摘The pyrolysis of different waste polymers （polyethylene, polypropylene and polystyrene） was investigated in a tube reactor at 550 ℃ in the absence of oxygen. Additionally the energetic utilization of products have also been followed both in refining and petrochemical industry. Pyrolysis products were separated into fractions of gases, naphtha, middle distillates and heavy oil. Raw materials have been collected both from industrial and household sources： polyethylene from agriculture, polyethylene from packaging and polystyrene from packaging and electronic equipments. Yields and properties of volatile products have changed by the raw materials. Products have been analyzed by gas chromatography. Fourier transformed infrared spectroscopy, size exclusion chromatography and other standardized methods. Naphtha had high octane numbers （80 〈 RON）, while high cetane numbers （〉 75） in case of middle distillates. Moreover fractions contained approximately half of unsaturated hydrocarbons, mainly α-olefins, but the percentage was depending on the raw materials. These properties are advantageous for fuel-like applications.
基金This work is supported by the National Key R&D Program of China(2020YFA0714400)Shaanxi Science&Technology Co-ordination&Innovation Project(2021GY-164).
文摘In this paper,a simple method to plate a hydrophobic coating on the inner surface of a small-scaled tube was proposed,where the coating consisted of carbon microspheres.Three common plastics polystyrene,polycarbonate and polyethylene were used as the feedstocks to be processed in supercritical water in a quartz tubular reactor.After reaction,the contact angle of droplet on the inner surface of the quartz tube was turned out to be over 100°,significantly larger than that of the blank tube 54°.When processing polystyrene in the 750℃ supercritical water for 10 min,the largest contact angle was obtained,up to 145°.Besides,in this sample,the size of carbon spheres was smallest,about 2.09μm diameter on average.When comparing among different types of plastics under the same condition,the contact angle of surface made from PC took the dominant position over that of PS and PE,124°,100°and 90°,respectively.In the sample made from PC,carbon spheres adhered into a mountainlike shape,producing a binary geometric structure.Furthermore,this research could be helpful in the discussion of plastic waste management and carbon spheres fabrication with low cost.
文摘New route of the utilization of products obtained by waste plastic pyrolysis has been investigated. ct-olefin-succinic-anhydride intermediate based on new experimental additives has been developed and used for achieving the better properties of carbon fibre reinforced polymer composites. Hydrocarbon fractions were produced by the pure thermal pyrolysis of waste polymers in a tube reactor using 550 ℃ in the absence of oxygen. Selected compounds （C30-C50） from pyrolysis products have been used as raw materials in the additive synthesis step. Polymer composite specimens have been investigated among others by universal tensile machine, SEM （scanning electron microscopy） and FTIR （fourier transformed infrared spectroscopy） methods. The tensile strength could be increased by 29.9%, the E-modulus by 24.2% and the Charpy impact strength by 13.3% in the presence of the experimental additive. Fibre-matrix interaction has been studied on SEM micrographs of the fractured face of composites. The results of mechanical testes have been supported by the SEM micrographs and possible shames of the coupling have been proposed.
基金The National Key Research and Development Program of China under contract No.2016YFC1402200the National Natural Science Foundation of China under contract No.41676190
文摘Marine plastic debris has been a pervasive issue since the last century, and research on its sources and fates plays a vital role in the establishment of mitigation measures. However, data on the quantity of plastic waste that enters the sea on a certain timescale remain largely unavailable in China. Here, we established a model using material flow analysis method based on life cycle assessment to follow plastic product from primary plastic to plastic waste with statistical data and monitoring data from accurate sources. This model can be used to estimate and forecast the annual input of plastic waste into the sea from China until 2020. In 2011, 0.547 3-0.751 5 million tons of plastic waste entered the seas in China, with a growth rate of 4.55% per year until 2017. And the amount will decrease to 0.257 1 to 0.353 1 million tons in 2020 under the influence of governmental management. The amount of plastic waste discharged from coastal areas calculated in this study was much larger than that from river, thus it is suggested to strengthen the governance and control of plastic waste in coastal fishery activities in China in order to reduce the amount of marine plastic waste input.
文摘PM_(1)0 samples were collected from an urban/industrial site nearby Athens,where uncontrolled burning activities occur.PAHs,monocarboxylic,dicarboxylic,hydroxycarboxylic and aromatic acids,tracers from BVOC oxidation,biomass burning tracers and bisphenol A were determined.PAH,monocarboxylic acids,biomass burning tracers and bisphenol A were increased during autumn/winter,while BSOA tracers,dicarboxylic-and hydroxycarboxylic acids during summer.Regarding aromatic acids,different sources and formation mechanisms were indicated as benzoic,phthalic and trimellitic acids were peaked during summer whereas p-toluic,isophthalic and terephthalic were more abundant during autumn/winter.The Benzo[a]pyrene-equivalent carcinogenic power,carcinogenic and mutagenic activities were calculated showing significant(p<0.05)increases during the colder months.Palmitic,succinic and malic acids were the most abundant monocarboxylic,dicarboxylic and hydrocarboxylic acids during the entire sampling period.Isoprene oxidation was the most significant contributor to BSOA as the isoprene-SOA compounds were two times more abundant than the pinene-SOA(13.4±12.3 and 6.1±2.9 ng/m^3,respectively).Ozone has significant impact on the formation of many studied compounds showing significant correlations with:isoprene-SOA(r=0.77),hydrocarboxylic acids(r=0.69),pinene-SOA(r=0.63),dicarboxylic acids(r=0.58),and the sum of phthalic,benzoic and trimellitic acids(r=0.44).PCA demonstrated five factors that could explain sources including plastic enriched waste burning(30.8%),oxidation of unsaturated fatty acids(23.0%),vehicle missions and cooking(9.2%),biomass burning(7.7%)and oxidation of VOCs(5.8%).The results highlight the significant contribution of plastic waste uncontrolled burning to the overall air quality degradation.
基金Supported by the National Natural Science Foundation of China(51503154,51776141)Major Projects of China Water Pollution Control and Treatment Science and Technology(2017ZX07202005)
文摘Waste plastics mainly come from MSW and usually exist in the form of mixed plastics. During the co-pyrolysis process of mixed plastics, various plastic components have different physicochemical properties and reaction mechanisms. Considering the high viscosity and low thermal conductivity of molten plastics, a falling film pyrolysis reactor was selected to explore the rapid co-pyrolysis process of typical plastic components(PP, PE and PS).The oil and gas yields and the compositions of pyrolysis products of the three components under different ratios at pyrolysis temperatures were analyzed to explore the co-pyrolysis characteristics of PP, PE, and PS. The study is of great significance to the recycling of waste plastics.
