Currently,the solid adsorbents with porous structure have been widely applied in CO_(2)capture.However,the unmodified MgO-ZrO_(2)adsorbents appeared to be low adsorption capacity of CO_(2).The solid adsorbent material...Currently,the solid adsorbents with porous structure have been widely applied in CO_(2)capture.However,the unmodified MgO-ZrO_(2)adsorbents appeared to be low adsorption capacity of CO_(2).The solid adsorbent materials were successfully synthesized by loading TEPA onto the pore MgO/ZrO_(2)carriers in the paper.The pore structure and surface characteristic of the samples were analyzed by using XRD,BET,FT-IR and SEM.The adsorbent materials exhibited microcrystalline state,and the crystallinity of all samples gradually decreased as the increase of TEPA content.The pore structure analysis indicated that the modification of MgO-ZrO_(2)adsorbents with TEPA led to the decrease of the specific surface areas,but the narrow micro-mesopore size distributions ranging from 1.8-12 nm in the adsorbents still were maintained.FT-IR spectrum results further verified the successful loading of TEPA.The adsorption capacity of the adsorbents for CO_(2)were tested by using an adsorption apparatus equipped with gas chromatography.The results indicated that when the TEPA loading reached 50%,the sample exhibited the maximum adsorption value for CO_(2),reaching 4.07 mmol/g under the operation condition of 75℃and atmospheric pressure.This result could be assigned to not only the base active sites but also the coexistence of both micropore and mesopore in the adsorbent.After three cycles tests for CO_(2)capture,the adsorption value of the sample for CO_(2)can also reached 95%of its original adsorption capacity,which verified the excellent cyclic operation stability.展开更多
Although supported solid amine adsorbents have attracted great attention for CO_(2) capture,critical chemical deactivation problems including oxidative degradation and urea formation have severely restricted their pra...Although supported solid amine adsorbents have attracted great attention for CO_(2) capture,critical chemical deactivation problems including oxidative degradation and urea formation have severely restricted their practical applications for flue gas CO_(2) capture.In this work,we reveal that the nature of surface hydroxyl groups(metal hydroxyl Al–OH and nonmetal hydroxyl Si–OH)plays a key role in the deactivation mechanisms.The polyethyleneimine(PEI)supported on Al–OH-containing substrates suffers from severe oxidative degradation during the CO_(2) capture step due to the breakage of amine-support hydrogen bonding networks,but exhibits an excellent anti-urea formation feature by preventing dehydration of carbamate products under a pure CO_(2) regeneration atmosphere.In contrast,PEI supported on Si–OHcontaining substrates exhibits excellent anti-oxidative stability under simulated flue gas conditions by forming a robust hydrogen bonding protective network with Si–OH,but suffers from obvious urea formation during the pure CO_(2) regeneration step.We also reveal that the urea formation problem for PEI-SBA-15 can be avoided by the incorporation of an OH-containing PEG additive.Based on the intrinsic understanding of degradation mechanisms,we successfully synthesized an adsorbent 40PEI-20PEG-SBA-15 that demonstrates outstanding stability and retention of a high CO_(2) capacity of 2.45 mmol g^(−1) over 1000 adsorption–desorption cycles,together with negligible capacity loss during aging in simulated flue gas(10%CO_(2)+5%O_(2)+3%H_(2)O)for one month at 60–70℃.We believe this work makes great contribution to the advancement in the field of ultra-stable solid amine-based CO_(2) capture materials.展开更多
The increase in energy demand caused by industrialization leads to abundant CO_2 emissions into atmosphere and induces abrupt rise in earth temperature. It is vital to acquire relatively simple and cost-effective tech...The increase in energy demand caused by industrialization leads to abundant CO_2 emissions into atmosphere and induces abrupt rise in earth temperature. It is vital to acquire relatively simple and cost-effective technologies to separate CO_2 from the flue gas and reduce its environmental impact. Solid adsorption is now considered an economic and least interfering way to capture CO_2, in that it can accomplish the goal of small energy penalty and few modifications to power plants. In this regard, we attempt to review the CO_2 adsorption performances of several types of solid adsorbents, including zeolites, clays, activated carbons, alkali metal oxides and carbonates, silica materials, metal–organic frameworks, covalent organic frameworks, and polymerized high internal phase emulsions. These solid adsorbents have been assessed in their CO_2 adsorption capacities along with other important parameters including adsorption kinetics, effect of water, recycling stability and regenerability. In particular,the superior properties of adsorbents enhanced by impregnating or grafting amine groups have been discussed for developing applicable candidates for industrial CO_2 capture.展开更多
Two organobentonites were synthesized by placing quaternary ammonium cationscetyltrimethylammonium bromide (CTMAB) and cetylpyridinium chloride (CPC) on bentonite bycation exchange. Their ability to adsorb phenol, ani...Two organobentonites were synthesized by placing quaternary ammonium cationscetyltrimethylammonium bromide (CTMAB) and cetylpyridinium chloride (CPC) on bentonite bycation exchange. Their ability to adsorb phenol, aniline. nitrobenzene and p-nitrophenol were examined.The optimal conditions for organobentonites to remove the organic pollutants from waterwere studied. The removal rates for organobentonites to treat the organic compounds in water werefound to be over 8 times for the original mineral (untreated bentonite).The removal rates of organic pollutants and COD of wastewater were further improved by organobentonites in the presence of aluminum sulfate. The structure of organobentonites and the mechanism for their adsorption were investigated by X-ray diffraction (XRD) analysis, infrared spectra and BET surface area.展开更多
The adsorption behavior ofp-aminobenzoic acid and o-aminobenzoic acid onto the different polymeric adsorbents was systematically investigated as a function of the solution concentration and temperature. Experimental r...The adsorption behavior ofp-aminobenzoic acid and o-aminobenzoic acid onto the different polymeric adsorbents was systematically investigated as a function of the solution concentration and temperature. Experimental results indicated that the equilibrium adsorption data of the four polymeric adsorbents fitted well in the Freundlich isotherm. The adsorption capacity of multi-functional polymeric adsorbent NJ-99 was the highest, which might be attributed to the strong hydrogen-bonding interaction between the amino groups on the resin and the carboxyl group of aminobenzoic acid. The adsorption capacity of o-aminobenzoic acid onto any adsorbent was higher than p-aminobenzoic acid. Thermodynamic studies suggested the exothermic, spontaneous physical adsorption process. Adsorption kinetics results showed that the adsorption followed the pseudo-second-order kinetics model and the intraparticle mass transfer process was the rate-controlling step.展开更多
Phosphine(PH3) is a highly toxic air pollutant,commonly produced in phosphorous chemical industry.But it has received less research attention due to its handling difficultly.CO is the main content of the phosphorous c...Phosphine(PH3) is a highly toxic air pollutant,commonly produced in phosphorous chemical industry.But it has received less research attention due to its handling difficultly.CO is the main content of the phosphorous chemical industry tail gas,the concentration of which is always more than 80 vol.%,and it can be the feed gas to produce various valuable products such as formate,oxalate,and methanol and so on.But,PH3 is one of the important barriers,which is harmful to the following chemical process.In order to make use of the tail gas,PH3 should be removed firstly,and CO should be covered in the whole purified procedure at the same time.In this work,the modified activated carbon(MAC) was used as the adsorbent to separate PH3 from the mixture tail gas.Series of MAC adsorbents were prepared for the adsorption of PH3,which loaded Cu-Fe and Ce(La),or separately.The PH3 adsorption capacities,chemical and physical properties of MAC were all investigated.The results showed that over 99% PH3 adsorption efficiency was achieved when used MAC adsorbents.The removal efficiency and PH3 adsorption capacity of the Cu-Fe-Ce/AC(20:1:0.4) were both much higher than those modified activated carbons.The maximum PH3 adsorption capacity was 71 mg of PH3/g of MAC on the Cu-Fe-Ce/AC,which were much higher than literature data using CuO only for adsorbing hydride gases.展开更多
Toxic heavy metal ions,valuable noble metal ions and organic dyes are significant concerns in wastewater treatment.In this work,MoO_(3) nanobelts(MoO_(3) NBs)prepared by solvothermal method and MoS_(2) nanoarrays(MoS_...Toxic heavy metal ions,valuable noble metal ions and organic dyes are significant concerns in wastewater treatment.In this work,MoO_(3) nanobelts(MoO_(3) NBs)prepared by solvothermal method and MoS_(2) nanoarrays(MoS_(2) NAs)constructed using MoO_(3) NBs precursor were proposed to effectively remove heavy/noble metal ions and organic dyes,such as Pb(II),Au(III)and Methylene Blue(MB).The two adsorbents exhibited the excellent adsorption capacity towards Pb(II),Au(III)and MB.The maximum removal capacity of Pb(II)and MB on MoO_(3) NBs was 684.93 mg/g and 1408 mg/g,respectively,whereas that of Au(III)and MB on MoS_(2) NAs was 1280.2 mg/g and 768 mg/g,respectively.Furthermore,the thermodynamic parameters were calculated from the temperature-dependent curves,suggesting that the removal of Pb(II)and Au(III)on both adsorbents was spontaneous and endothermic.The new adsorbents introduced here were high adsorption activity,ease of fabrication,high scalability,good chemical stability,great repeatability and abundant and cheap supply,which were highly attractive for wastewater treatment.展开更多
With the continuous growth of the world population,the demand for fresh water is ever increasing.Water desalination is a means of producing fresh water from saline water,and one of the proposed solutions in the scient...With the continuous growth of the world population,the demand for fresh water is ever increasing.Water desalination is a means of producing fresh water from saline water,and one of the proposed solutions in the scientific community for solving the current global freshwater shortage.Adsorption is foreseen as a promising technology for desalination due to its relatively low energy requirements,low environmental impact,low cost and high salt removal efficiency.More importantly,chemicals are not required in adsorption processes.Active carbons,zeolites,carbon nanostructures,graphene and coordination framework materials are amongst the most investigated adsorbents for adsorption desalination,which show different performances regarding adsorption rate,adsorption capacity,stability and recyclability.In this review,the latest adsorbent materials with their features are assessed(using metrics)and commented critically,and the current trend for their development is discussed.The adsorption mode is also reviewed,which can provide guidance for the design of adsorbents from the engineering application point of view.展开更多
A series of MgO-based adsorbents were prepared through solution–combustion synthesis and ball-milling process.The prepared MgO-based powders were characterized using X-ray diffraction,scanning electron microscopy,N_2...A series of MgO-based adsorbents were prepared through solution–combustion synthesis and ball-milling process.The prepared MgO-based powders were characterized using X-ray diffraction,scanning electron microscopy,N_2 physisorption measurements,and employed as potential adsorbents for CO_2 adsorption.The influence of structural and textural properties of these adsorbents over the CO_2 adsorption behaviour was also investigated.The results showed that MgO-based products prepared by solution–combustion and ball-milling processes,were highly porous,fluffy,nanocrystalline structures in nature,which are unique physico-chemical properties that significantly contribute to enhance their CO_2 adsorption.It was found that the MgO synthesized by solution combustion process,using a molar ratio of urea to magnesium nitrate（2：1）,and treated by ball-milling during 2.5 hr（MgO-BM2.5h）,exhibited the maximum CO_2 adsorption capacity of 1.611 mmol/g at 25℃ and 1 atm,mainly via chemisorption.The CO_2 adsorption behaviour on the MgO-based adsorbents was correlated to their improved specific surface area,total pore volume,pore size distribution and crystallinity.The reusability of synthesized MgO-BM2.5h was confirmed by five consecutive CO_2adsorption–desorption times,without any significant loss of performance,that supports the potential of MgO-based adsorbent.The results confirmed that the special features of MgO prepared by solution–combustion and treated by ball-milling during 2.5 hr are favorable to be used as effective MgO-based adsorbent in post-combustion CO_2 capture technologies.展开更多
Removal of dye from the industrial wastewater is one of the most important subjects in water pollution regulation.Successive adsorption/desorption cycles of a basic dye, methylene blue, on the internal almond shell, s...Removal of dye from the industrial wastewater is one of the most important subjects in water pollution regulation.Successive adsorption/desorption cycles of a basic dye, methylene blue, on the internal almond shell, sheep manure waste and sawdust were investigated using fixed bed column experiments in order to study the adsorption capacity to remove MB and adsorbent regeneration efficiency. The adsorption breakthrough curves were predicted by the Thomas model, Yoon Nelson model, and Wolborska model and modified dose–response model using non-linear regression analysis. The results showed that the modified dose–response model was more suitable for the description of breakthrough curves for three adsorbents only in the first cycle. Although sheep manure waste presents the highest adsorption capacity, it is hard to regenerate and needs more time regeneration. Conversely, the internal almond shell presents lower adsorption capacity, but they are more readily regenerated.展开更多
BACKGROUND: Molecular adsorbents recirculating sys- tem (MARS) liver support therapy is the development of albumin dialysis. This study was to assess the successful ap- plication of MARS artificial liver support thera...BACKGROUND: Molecular adsorbents recirculating sys- tem (MARS) liver support therapy is the development of albumin dialysis. This study was to assess the successful ap- plication of MARS artificial liver support therapy as a bridge to re-transplantation in two cases of long anhepatic duration. METHODS: MARS therapy was given after failure plasma- exchange ( PE) treatment, which resulted in circulatory de- rangement and acute renal dysfunction in a 36-year-old male patient. Finally his uncontrolled anhepatic condition led to a successful re-transplantation. In another 48-year- old man who was diagnosed as having primary nonfunction (PNF) during the liver transplantation, 10-hour MARS treatment contributed to smooth bridging of his anhepatic phase. RESULTS: The two anhepatic patients were bridged for 26 and 17 hours respectively to re-transplantation with MARS therapy. CONCLUSION: Our experience proves that MARS artifi- cial liver can be an effective support for long time bridging PNF until re-transplantation is available.展开更多
A sensor based on the technique of a piezoelectric quartz crystal microbalance (QCM) is analyzed for the detection of six organic volatile compounds with high olive oil sensory significance, such as hexanal, acetic ac...A sensor based on the technique of a piezoelectric quartz crystal microbalance (QCM) is analyzed for the detection of six organic volatile compounds with high olive oil sensory significance, such as hexanal, acetic acid, Z-3-hexenyl acetate, undecane, 1-octen-3-ol and 2-butanone. Four sample concentrations have been exposed to each QCM sensor constructed. The detection system is based on the sample adsorption on the forty sensing films coated at the surfaces of forty AT-cut gold-coated quartz crystals. Each sensing film has been prepared with different solution concentrations of ten materials, usually used as chromatographic sta-tionary phases. Sensing film coating process shows excellent repeatability, with coefficient values less than 0.50%. The frequency shifts of the piezoelectric crystals due to the adsorption of the volatile compounds have been measured as sensor responses, using a static measurement system. The results show that only five QCM sensors, with high sensitivity values, are enough to the detection of the volatile compounds studied. Therefore, the developed detection system presented herein provides a rapid identification of organic volatile compounds with elevated olive oil sensory connotation and it could be a substitute technique to the analytical methods normally used for the analysis of the olive oil flavor.展开更多
Desorption of volatile organic compounds (VOCs) from polymeric adsorbents by microwave was investigated experimentally. Two kinds of organic compounds, benzene and toluene, were separately used as adsorbates in this w...Desorption of volatile organic compounds (VOCs) from polymeric adsorbents by microwave was investigated experimentally. Two kinds of organic compounds, benzene and toluene, were separately used as adsorbates in this work. Results showed that the application of microwave to regenerate the polymeric adsorbents not only can get higher regeneration efficiency in comparison with the use of heat regeneration, but also make the temperatures of the fixed beds much lower than that when using the heat regeneration. The weaker the polarity of a polymeric adsorbent, the easier its regeneration was.展开更多
The protein-bound uremic toxins,represented by indoxyl sulfate(IS),have been associated with the progression of chronic kidney disease and the development of cardiovascular disease in the presence of impaired renal fu...The protein-bound uremic toxins,represented by indoxyl sulfate(IS),have been associated with the progression of chronic kidney disease and the development of cardiovascular disease in the presence of impaired renal function.Herein,we proposed a novel strategy of thin-film nanofibrous composite(TNFC)dialysis membrane combined with reduced graphene oxide(rGO)aerogel adsorbents for clinical removal of IS as well as high retention of proteins.The TFNC membrane was prepared by electrospinning in conjunction with coating-reaction method and proved to have good selectivity and permeability.To further improve the removal rate of toxins,we used a medium hydrothermal method following by freeze-drying treatment to obtain the r GO aerogel adsorbents.It exhibited excellent adsorption for IS with a maximum adsorption capacity of 69.40 mg·g^(-1)throughπ-πinteraction and hydrogen bonding interaction based on Langmuir isotherm models.Time-dependent absorption experiments showed that it reached adsorption equilibrium within 4 h,which was matched with the hemodialysis time.The coordination was significantly exhibited by introducing r GO aerogel blocks into the dialysate for absorbing the diffused free IS during hemodialysis.Taking the advantages of the TFNC dialysis membrane and the rGO aerogel,the volume of dialysate for hemodialysis was only one-tenth of that without adsorbent blocks but with very comparable dialysis performance(the clearance of IS at 51.8%and the retention of HSA over 98%),which could lighten conventional hemodialysis effectively and be benefit to realize the miniaturization of the hemodialysis equipment.Therefore,the coordination of the TFNC dialysis membrane and rGO aerogel adsorbents would open a new path for the development of portable artificial kidney.展开更多
Amines in porous materials have been employed as active species for the selective CO_(2) adsorption from natural gas because of their target-specific interactions.Nevertheless,it is difficult to modulate such strong i...Amines in porous materials have been employed as active species for the selective CO_(2) adsorption from natural gas because of their target-specific interactions.Nevertheless,it is difficult to modulate such strong interactions to reach a high efficiency in the adsorption processes.Herein,we fabricated lightresponsive adsorbents with tunable adsorbent–adsorbate interactions for CO_(2) capture.The adsorbents were synthesized by introducing primary and secondary amines into a mesoporous silica that had been grafted with azobenzene groups on the surfaces.The target-specific amine sites render the adsorbents significantly selective in the uptake of CO_(2) over CH_(4),and the azobenzene groups were used as lightresponsive switches to influence the adsorbent–adsorbate interactions.The adsorbents can freely adsorb CO_(2) when the azobenzene groups are in the trans state.Ultraviolet-light irradiation makes the azobenzene groups transform to the cis configuration,which greatly hinders amines in the uptake of CO_(2).The caused difference of adsorption capacity can reach 34.9%.The alternative irradiation by ultravioletand visible-light can lead to a recyclable regulation on adsorption performance.The changes of the electrostatic potentials of amines are responsible for the light-induced regulation on adsorption.展开更多
In the present study the adsorptive properties of p-aminobenzoic acid with hypercrosslinked and multi-functional polymeric adsorbents at different solution pHs were systematically investigated in accordance with the p...In the present study the adsorptive properties of p-aminobenzoic acid with hypercrosslinked and multi-functional polymeric adsorbents at different solution pHs were systematically investigated in accordance with the particular physicochemical characteristics of the aromatic amphoteric compound involving both Lewis acid and Lewis base functional groups. It was found that the equilibrium adsorption data of the three polymeric adsorbents fitted well in the Langmuir and Freundlich isotherm equations. Studies at various pH levels indicate that the capacity of the adsorbents for adsorption of the ionic forms of adsorbate is less than that for the corresponding neutral species. At pH 3.78, the adsorption capacities of the three adsorbents are the highest. Whereas the adsorption property of multi-functional polymeric adsorbent NJ-99 is the largest, which may be attributed to the strong hydrogen-bonding interaction between the amino groups on the resin and the carboxyl group of p-aminobenzoic acid. The trend of the adsorption capacities of the three adsorbents towards p-aminobenzoic acid with the solution pH is in accord with the dissociation curve of the neutral molecular p-aminobenzoic acid. The adsorption forces include π-π interaction, hydrogen-bonding interaction and electrostatic attraction or repulsion when there exist the molecular and ionic adsorbing species at different pHs in aqueous solution.展开更多
Arsenic is a highly toxic element and its contamination in water bodies is a worldwide problem. Arsenic adsorption with metal oxides/hydroxides-based adsorbents is an effective approach to remove arsenic species from ...Arsenic is a highly toxic element and its contamination in water bodies is a worldwide problem. Arsenic adsorption with metal oxides/hydroxides-based adsorbents is an effective approach to remove arsenic species from water for the health of both human beings and the environment. However, no material criterion had been proposed for the selection of potential candidates. Equally puzzling is the fact that no clear explanation was available on the poor arsenic adsorption performance of some commonly used adsorbents, such as active carbon or silica. Furthermore, in-depth examination was also not available for the dramatically different competing adsorption effects of various anions on the arsenic adsorption. Through the arsenic adsorption mechanism study on these highly efficient arsenic adsorbents, we found that ionic potential could be used as a general material criterion for the selection of highly efficient arsenic adsorbents and such a criterion could help us to understand the above questions on arsenic adsorbents. This material criterion could be further applied to the selection of highly efficient adsorbents based on ligand exchange between their surface hydroxyl groups and adsorbates in general, which may be used for the prediction of novel adsorbents for the removal of various contaminations in water.展开更多
We predicted two stable two-dimensional materials of carbon and bismuth elements,namely BiC and Bi_(2)C monolayers.The stabilities of two monolayers were examined by cohesive energy,Born criteria,first-principle MD si...We predicted two stable two-dimensional materials of carbon and bismuth elements,namely BiC and Bi_(2)C monolayers.The stabilities of two monolayers were examined by cohesive energy,Born criteria,first-principle MD simulations and phonon spectra,respectively.By including the spin-orbit coupling effects,the BiC monolayer is a metal and the Bi_(2)C monolayer possesses a narrow direct(indirect)band gap of 0.403(0.126)eV under the HSE06(GGA-PBE)functional.For the adsorption of CO_(2)molecules,the BiC and Bi_(2)C monolayers have three stable adsorption sites C2,T3 and T4 with the adsorption energies as-0.57,-0.51 and-0.81 eV,and the activation ability on the adsorption as T4>T3>C2.These consequences make the BiC and Bi_(2)C monolayers to be promising adsorbents to capture CO_(2)gas,the Bi_(2)C monolayer to be well photovoltaics and optoelectronics material,and the BiC monolayer to be ideal battery and electronics materials,respectively.展开更多
Several macroporous polymeric adsorbents (NDA-999, XAD-8, X-5 and XAD-2) were employed in the study to adsorb phenylacetic acid from aqueous solution. Effect of salt and ambient temperature on adsorption was studied u...Several macroporous polymeric adsorbents (NDA-999, XAD-8, X-5 and XAD-2) were employed in the study to adsorb phenylacetic acid from aqueous solution. Effect of salt and ambient temperature on adsorption was studied using NDA-999 adsorbent and the adsorption process conforms to Freundlich抯 model reasonably. Adsorption dynamics were conducted in batch experiments in order to make clear the mechanism of adsorption process. It is proved that the squared driving force mass transfer model can be adopted to elucidate the process. The treatment process of industrial wastewater containing high strength of phenylacetic acid was proposed for cleaner production of phenylacetic acid.展开更多
The carbonaceous adsorbent was prepared from mixtures of dewatered sludge and sawdust with enhanced ZnCl2 chemical activation.Characteristics of the adsorbent were studied using scanning electron microscope(SEM) ,Four...The carbonaceous adsorbent was prepared from mixtures of dewatered sludge and sawdust with enhanced ZnCl2 chemical activation.Characteristics of the adsorbent were studied using scanning electron microscope(SEM) ,Fourier transform infrared spectroscopy(FT-IR) ,and adsorption of nitrogen.The surface analysis showed that the carbonaceous adsorbent had good specific surface and porosity(394 m 2 ·g-1of BET surface,0.12 and 0.10 ml·g-1of microporous and mesoporous volume,respectively) .The oxygen functional groups such as OH,C O and C O were found on the surface by FTIR and XPS(X-ray photoelectron spectroscopy) .The adsorption of elemental mercury(Hg0) on the carbonaceous adsorbent was studied in a fixed bed reactor.The dynamic adsorption capacity of carbonaceous adsorbent increased with influent mercury concentration,from 23.6μg·g-1at 12.58μg·m-3to 87.9μg·g-1at 72.50μg·m-3,and decreased as the adsorption temperature increased,from 246 μg·g-1 at 25°C to 61.3μg·g-1 at 140°C,when dry nitrogen was used as the carrier gas.The carbonaceous adsorbent presented higher dynamic adsorption capacity than activated carbon,which was 81.2μg·g-1and 53.8μg·g-1respectively.The adsorption data were fitted to the Langmuir adsorption model.The physical and chemical adsorption were identified on the adsorbent.展开更多
基金supported by Shanxi Provincial Key Research and Development Project(202102090301026)Graduate Education Innovation Project of Taiyuan University of Science and Technology(SY2023024)。
文摘Currently,the solid adsorbents with porous structure have been widely applied in CO_(2)capture.However,the unmodified MgO-ZrO_(2)adsorbents appeared to be low adsorption capacity of CO_(2).The solid adsorbent materials were successfully synthesized by loading TEPA onto the pore MgO/ZrO_(2)carriers in the paper.The pore structure and surface characteristic of the samples were analyzed by using XRD,BET,FT-IR and SEM.The adsorbent materials exhibited microcrystalline state,and the crystallinity of all samples gradually decreased as the increase of TEPA content.The pore structure analysis indicated that the modification of MgO-ZrO_(2)adsorbents with TEPA led to the decrease of the specific surface areas,but the narrow micro-mesopore size distributions ranging from 1.8-12 nm in the adsorbents still were maintained.FT-IR spectrum results further verified the successful loading of TEPA.The adsorption capacity of the adsorbents for CO_(2)were tested by using an adsorption apparatus equipped with gas chromatography.The results indicated that when the TEPA loading reached 50%,the sample exhibited the maximum adsorption value for CO_(2),reaching 4.07 mmol/g under the operation condition of 75℃and atmospheric pressure.This result could be assigned to not only the base active sites but also the coexistence of both micropore and mesopore in the adsorbent.After three cycles tests for CO_(2)capture,the adsorption value of the sample for CO_(2)can also reached 95%of its original adsorption capacity,which verified the excellent cyclic operation stability.
基金supported by the Fundamental Research Funds for the National Natural Science Foundation of China 52225003,22208021,22109004the National Key R&D Program of China 2022YFB4101702.
文摘Although supported solid amine adsorbents have attracted great attention for CO_(2) capture,critical chemical deactivation problems including oxidative degradation and urea formation have severely restricted their practical applications for flue gas CO_(2) capture.In this work,we reveal that the nature of surface hydroxyl groups(metal hydroxyl Al–OH and nonmetal hydroxyl Si–OH)plays a key role in the deactivation mechanisms.The polyethyleneimine(PEI)supported on Al–OH-containing substrates suffers from severe oxidative degradation during the CO_(2) capture step due to the breakage of amine-support hydrogen bonding networks,but exhibits an excellent anti-urea formation feature by preventing dehydration of carbamate products under a pure CO_(2) regeneration atmosphere.In contrast,PEI supported on Si–OHcontaining substrates exhibits excellent anti-oxidative stability under simulated flue gas conditions by forming a robust hydrogen bonding protective network with Si–OH,but suffers from obvious urea formation during the pure CO_(2) regeneration step.We also reveal that the urea formation problem for PEI-SBA-15 can be avoided by the incorporation of an OH-containing PEG additive.Based on the intrinsic understanding of degradation mechanisms,we successfully synthesized an adsorbent 40PEI-20PEG-SBA-15 that demonstrates outstanding stability and retention of a high CO_(2) capacity of 2.45 mmol g^(−1) over 1000 adsorption–desorption cycles,together with negligible capacity loss during aging in simulated flue gas(10%CO_(2)+5%O_(2)+3%H_(2)O)for one month at 60–70℃.We believe this work makes great contribution to the advancement in the field of ultra-stable solid amine-based CO_(2) capture materials.
基金Supported by the National Key Research & Development Program of China(2017YFB0603302)
文摘The increase in energy demand caused by industrialization leads to abundant CO_2 emissions into atmosphere and induces abrupt rise in earth temperature. It is vital to acquire relatively simple and cost-effective technologies to separate CO_2 from the flue gas and reduce its environmental impact. Solid adsorption is now considered an economic and least interfering way to capture CO_2, in that it can accomplish the goal of small energy penalty and few modifications to power plants. In this regard, we attempt to review the CO_2 adsorption performances of several types of solid adsorbents, including zeolites, clays, activated carbons, alkali metal oxides and carbonates, silica materials, metal–organic frameworks, covalent organic frameworks, and polymerized high internal phase emulsions. These solid adsorbents have been assessed in their CO_2 adsorption capacities along with other important parameters including adsorption kinetics, effect of water, recycling stability and regenerability. In particular,the superior properties of adsorbents enhanced by impregnating or grafting amine groups have been discussed for developing applicable candidates for industrial CO_2 capture.
文摘Two organobentonites were synthesized by placing quaternary ammonium cationscetyltrimethylammonium bromide (CTMAB) and cetylpyridinium chloride (CPC) on bentonite bycation exchange. Their ability to adsorb phenol, aniline. nitrobenzene and p-nitrophenol were examined.The optimal conditions for organobentonites to remove the organic pollutants from waterwere studied. The removal rates for organobentonites to treat the organic compounds in water werefound to be over 8 times for the original mineral (untreated bentonite).The removal rates of organic pollutants and COD of wastewater were further improved by organobentonites in the presence of aluminum sulfate. The structure of organobentonites and the mechanism for their adsorption were investigated by X-ray diffraction (XRD) analysis, infrared spectra and BET surface area.
基金Project supported by the National Key Technology Research and Development Program of China(No.2006BAC02A15)Opening Foundation of Jiangsu Provincial Key Laboratory of Coastal Wetland Bioresources and Environmental Protection of China(No.JLCBE05006)the Qinglan Project of Jiangsu Province
文摘The adsorption behavior ofp-aminobenzoic acid and o-aminobenzoic acid onto the different polymeric adsorbents was systematically investigated as a function of the solution concentration and temperature. Experimental results indicated that the equilibrium adsorption data of the four polymeric adsorbents fitted well in the Freundlich isotherm. The adsorption capacity of multi-functional polymeric adsorbent NJ-99 was the highest, which might be attributed to the strong hydrogen-bonding interaction between the amino groups on the resin and the carboxyl group of aminobenzoic acid. The adsorption capacity of o-aminobenzoic acid onto any adsorbent was higher than p-aminobenzoic acid. Thermodynamic studies suggested the exothermic, spontaneous physical adsorption process. Adsorption kinetics results showed that the adsorption followed the pseudo-second-order kinetics model and the intraparticle mass transfer process was the rate-controlling step.
基金Project supported by the Key Program of National High Technology Research and Development Program of China (863 Program) (2008AA062602)the Young and Middle-aged Academic and Technical Back-up Personnel Program of Yunnan Province (2007PY01-10)
文摘Phosphine(PH3) is a highly toxic air pollutant,commonly produced in phosphorous chemical industry.But it has received less research attention due to its handling difficultly.CO is the main content of the phosphorous chemical industry tail gas,the concentration of which is always more than 80 vol.%,and it can be the feed gas to produce various valuable products such as formate,oxalate,and methanol and so on.But,PH3 is one of the important barriers,which is harmful to the following chemical process.In order to make use of the tail gas,PH3 should be removed firstly,and CO should be covered in the whole purified procedure at the same time.In this work,the modified activated carbon(MAC) was used as the adsorbent to separate PH3 from the mixture tail gas.Series of MAC adsorbents were prepared for the adsorption of PH3,which loaded Cu-Fe and Ce(La),or separately.The PH3 adsorption capacities,chemical and physical properties of MAC were all investigated.The results showed that over 99% PH3 adsorption efficiency was achieved when used MAC adsorbents.The removal efficiency and PH3 adsorption capacity of the Cu-Fe-Ce/AC(20:1:0.4) were both much higher than those modified activated carbons.The maximum PH3 adsorption capacity was 71 mg of PH3/g of MAC on the Cu-Fe-Ce/AC,which were much higher than literature data using CuO only for adsorbing hydride gases.
基金supported by the National Natural Science Foundation of China(No.21505106)the Fundamental Research Funds for the Central Universities(No.2452017177)。
文摘Toxic heavy metal ions,valuable noble metal ions and organic dyes are significant concerns in wastewater treatment.In this work,MoO_(3) nanobelts(MoO_(3) NBs)prepared by solvothermal method and MoS_(2) nanoarrays(MoS_(2) NAs)constructed using MoO_(3) NBs precursor were proposed to effectively remove heavy/noble metal ions and organic dyes,such as Pb(II),Au(III)and Methylene Blue(MB).The two adsorbents exhibited the excellent adsorption capacity towards Pb(II),Au(III)and MB.The maximum removal capacity of Pb(II)and MB on MoO_(3) NBs was 684.93 mg/g and 1408 mg/g,respectively,whereas that of Au(III)and MB on MoS_(2) NAs was 1280.2 mg/g and 768 mg/g,respectively.Furthermore,the thermodynamic parameters were calculated from the temperature-dependent curves,suggesting that the removal of Pb(II)and Au(III)on both adsorbents was spontaneous and endothermic.The new adsorbents introduced here were high adsorption activity,ease of fabrication,high scalability,good chemical stability,great repeatability and abundant and cheap supply,which were highly attractive for wastewater treatment.
基金the Spanish Ministerio de Economía y Competitividadthe European Social Fund for her Ramon y Cajal Fellowship (RYC2019-027060-I/AEI/10.13039/5011 00011033)the China Scholarship Council (202006240076)-University of Manchester joint studentship
文摘With the continuous growth of the world population,the demand for fresh water is ever increasing.Water desalination is a means of producing fresh water from saline water,and one of the proposed solutions in the scientific community for solving the current global freshwater shortage.Adsorption is foreseen as a promising technology for desalination due to its relatively low energy requirements,low environmental impact,low cost and high salt removal efficiency.More importantly,chemicals are not required in adsorption processes.Active carbons,zeolites,carbon nanostructures,graphene and coordination framework materials are amongst the most investigated adsorbents for adsorption desalination,which show different performances regarding adsorption rate,adsorption capacity,stability and recyclability.In this review,the latest adsorbent materials with their features are assessed(using metrics)and commented critically,and the current trend for their development is discussed.The adsorption mode is also reviewed,which can provide guidance for the design of adsorbents from the engineering application point of view.
基金the National Institute of Nuclear Research(ININ),México,for financial support through project CB-406 stagesⅠ-Ⅲ
文摘A series of MgO-based adsorbents were prepared through solution–combustion synthesis and ball-milling process.The prepared MgO-based powders were characterized using X-ray diffraction,scanning electron microscopy,N_2 physisorption measurements,and employed as potential adsorbents for CO_2 adsorption.The influence of structural and textural properties of these adsorbents over the CO_2 adsorption behaviour was also investigated.The results showed that MgO-based products prepared by solution–combustion and ball-milling processes,were highly porous,fluffy,nanocrystalline structures in nature,which are unique physico-chemical properties that significantly contribute to enhance their CO_2 adsorption.It was found that the MgO synthesized by solution combustion process,using a molar ratio of urea to magnesium nitrate（2：1）,and treated by ball-milling during 2.5 hr（MgO-BM2.5h）,exhibited the maximum CO_2 adsorption capacity of 1.611 mmol/g at 25℃ and 1 atm,mainly via chemisorption.The CO_2 adsorption behaviour on the MgO-based adsorbents was correlated to their improved specific surface area,total pore volume,pore size distribution and crystallinity.The reusability of synthesized MgO-BM2.5h was confirmed by five consecutive CO_2adsorption–desorption times,without any significant loss of performance,that supports the potential of MgO-based adsorbent.The results confirmed that the special features of MgO prepared by solution–combustion and treated by ball-milling during 2.5 hr are favorable to be used as effective MgO-based adsorbent in post-combustion CO_2 capture technologies.
文摘Removal of dye from the industrial wastewater is one of the most important subjects in water pollution regulation.Successive adsorption/desorption cycles of a basic dye, methylene blue, on the internal almond shell, sheep manure waste and sawdust were investigated using fixed bed column experiments in order to study the adsorption capacity to remove MB and adsorbent regeneration efficiency. The adsorption breakthrough curves were predicted by the Thomas model, Yoon Nelson model, and Wolborska model and modified dose–response model using non-linear regression analysis. The results showed that the modified dose–response model was more suitable for the description of breakthrough curves for three adsorbents only in the first cycle. Although sheep manure waste presents the highest adsorption capacity, it is hard to regenerate and needs more time regeneration. Conversely, the internal almond shell presents lower adsorption capacity, but they are more readily regenerated.
文摘BACKGROUND: Molecular adsorbents recirculating sys- tem (MARS) liver support therapy is the development of albumin dialysis. This study was to assess the successful ap- plication of MARS artificial liver support therapy as a bridge to re-transplantation in two cases of long anhepatic duration. METHODS: MARS therapy was given after failure plasma- exchange ( PE) treatment, which resulted in circulatory de- rangement and acute renal dysfunction in a 36-year-old male patient. Finally his uncontrolled anhepatic condition led to a successful re-transplantation. In another 48-year- old man who was diagnosed as having primary nonfunction (PNF) during the liver transplantation, 10-hour MARS treatment contributed to smooth bridging of his anhepatic phase. RESULTS: The two anhepatic patients were bridged for 26 and 17 hours respectively to re-transplantation with MARS therapy. CONCLUSION: Our experience proves that MARS artifi- cial liver can be an effective support for long time bridging PNF until re-transplantation is available.
文摘A sensor based on the technique of a piezoelectric quartz crystal microbalance (QCM) is analyzed for the detection of six organic volatile compounds with high olive oil sensory significance, such as hexanal, acetic acid, Z-3-hexenyl acetate, undecane, 1-octen-3-ol and 2-butanone. Four sample concentrations have been exposed to each QCM sensor constructed. The detection system is based on the sample adsorption on the forty sensing films coated at the surfaces of forty AT-cut gold-coated quartz crystals. Each sensing film has been prepared with different solution concentrations of ten materials, usually used as chromatographic sta-tionary phases. Sensing film coating process shows excellent repeatability, with coefficient values less than 0.50%. The frequency shifts of the piezoelectric crystals due to the adsorption of the volatile compounds have been measured as sensor responses, using a static measurement system. The results show that only five QCM sensors, with high sensitivity values, are enough to the detection of the volatile compounds studied. Therefore, the developed detection system presented herein provides a rapid identification of organic volatile compounds with elevated olive oil sensory connotation and it could be a substitute technique to the analytical methods normally used for the analysis of the olive oil flavor.
文摘Desorption of volatile organic compounds (VOCs) from polymeric adsorbents by microwave was investigated experimentally. Two kinds of organic compounds, benzene and toluene, were separately used as adsorbates in this work. Results showed that the application of microwave to regenerate the polymeric adsorbents not only can get higher regeneration efficiency in comparison with the use of heat regeneration, but also make the temperatures of the fixed beds much lower than that when using the heat regeneration. The weaker the polarity of a polymeric adsorbent, the easier its regeneration was.
基金supported by the Fundamental Research Funds for the Central Universities(2232020A-04)Natural Science Foundation of Shanghai City(19ZR1401300)。
文摘The protein-bound uremic toxins,represented by indoxyl sulfate(IS),have been associated with the progression of chronic kidney disease and the development of cardiovascular disease in the presence of impaired renal function.Herein,we proposed a novel strategy of thin-film nanofibrous composite(TNFC)dialysis membrane combined with reduced graphene oxide(rGO)aerogel adsorbents for clinical removal of IS as well as high retention of proteins.The TFNC membrane was prepared by electrospinning in conjunction with coating-reaction method and proved to have good selectivity and permeability.To further improve the removal rate of toxins,we used a medium hydrothermal method following by freeze-drying treatment to obtain the r GO aerogel adsorbents.It exhibited excellent adsorption for IS with a maximum adsorption capacity of 69.40 mg·g^(-1)throughπ-πinteraction and hydrogen bonding interaction based on Langmuir isotherm models.Time-dependent absorption experiments showed that it reached adsorption equilibrium within 4 h,which was matched with the hemodialysis time.The coordination was significantly exhibited by introducing r GO aerogel blocks into the dialysate for absorbing the diffused free IS during hemodialysis.Taking the advantages of the TFNC dialysis membrane and the rGO aerogel,the volume of dialysate for hemodialysis was only one-tenth of that without adsorbent blocks but with very comparable dialysis performance(the clearance of IS at 51.8%and the retention of HSA over 98%),which could lighten conventional hemodialysis effectively and be benefit to realize the miniaturization of the hemodialysis equipment.Therefore,the coordination of the TFNC dialysis membrane and rGO aerogel adsorbents would open a new path for the development of portable artificial kidney.
基金supported by the National Natural Science Foun-dation of China(22078155,21808110,21878149,and 21676138)China Postdoctoral Science Foundation(2020M681567)。
文摘Amines in porous materials have been employed as active species for the selective CO_(2) adsorption from natural gas because of their target-specific interactions.Nevertheless,it is difficult to modulate such strong interactions to reach a high efficiency in the adsorption processes.Herein,we fabricated lightresponsive adsorbents with tunable adsorbent–adsorbate interactions for CO_(2) capture.The adsorbents were synthesized by introducing primary and secondary amines into a mesoporous silica that had been grafted with azobenzene groups on the surfaces.The target-specific amine sites render the adsorbents significantly selective in the uptake of CO_(2) over CH_(4),and the azobenzene groups were used as lightresponsive switches to influence the adsorbent–adsorbate interactions.The adsorbents can freely adsorb CO_(2) when the azobenzene groups are in the trans state.Ultraviolet-light irradiation makes the azobenzene groups transform to the cis configuration,which greatly hinders amines in the uptake of CO_(2).The caused difference of adsorption capacity can reach 34.9%.The alternative irradiation by ultravioletand visible-light can lead to a recyclable regulation on adsorption performance.The changes of the electrostatic potentials of amines are responsible for the light-induced regulation on adsorption.
基金This work was supported by the Opening Foundation of Jiangsu Provincial Key Laboratory of Coastal Wetland Bioresources and Environmental Protection of China (No. JLCBE05006).
文摘In the present study the adsorptive properties of p-aminobenzoic acid with hypercrosslinked and multi-functional polymeric adsorbents at different solution pHs were systematically investigated in accordance with the particular physicochemical characteristics of the aromatic amphoteric compound involving both Lewis acid and Lewis base functional groups. It was found that the equilibrium adsorption data of the three polymeric adsorbents fitted well in the Langmuir and Freundlich isotherm equations. Studies at various pH levels indicate that the capacity of the adsorbents for adsorption of the ionic forms of adsorbate is less than that for the corresponding neutral species. At pH 3.78, the adsorption capacities of the three adsorbents are the highest. Whereas the adsorption property of multi-functional polymeric adsorbent NJ-99 is the largest, which may be attributed to the strong hydrogen-bonding interaction between the amino groups on the resin and the carboxyl group of p-aminobenzoic acid. The trend of the adsorption capacities of the three adsorbents towards p-aminobenzoic acid with the solution pH is in accord with the dissociation curve of the neutral molecular p-aminobenzoic acid. The adsorption forces include π-π interaction, hydrogen-bonding interaction and electrostatic attraction or repulsion when there exist the molecular and ionic adsorbing species at different pHs in aqueous solution.
基金supported by the Knowledge Innovation Program of Institute of Metal Research,Chinese Academy of Sciences(Grant No.Y0N5A111A1)the Youth Innovation Promotion Association,Chinese Academy of Sciences(Grant No.Y2N5711171)the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry,China
文摘Arsenic is a highly toxic element and its contamination in water bodies is a worldwide problem. Arsenic adsorption with metal oxides/hydroxides-based adsorbents is an effective approach to remove arsenic species from water for the health of both human beings and the environment. However, no material criterion had been proposed for the selection of potential candidates. Equally puzzling is the fact that no clear explanation was available on the poor arsenic adsorption performance of some commonly used adsorbents, such as active carbon or silica. Furthermore, in-depth examination was also not available for the dramatically different competing adsorption effects of various anions on the arsenic adsorption. Through the arsenic adsorption mechanism study on these highly efficient arsenic adsorbents, we found that ionic potential could be used as a general material criterion for the selection of highly efficient arsenic adsorbents and such a criterion could help us to understand the above questions on arsenic adsorbents. This material criterion could be further applied to the selection of highly efficient adsorbents based on ligand exchange between their surface hydroxyl groups and adsorbates in general, which may be used for the prediction of novel adsorbents for the removal of various contaminations in water.
基金funded by the Natural Science Foundation of China(Nos.21603109,11304128)the Henan Joint Fund of the National Natural Science Foundation of China(No.U1404216)+1 种基金the Science and Technology Program of Henan Department of Science and Technology,China(No.182102310609)the Construct Program of Applied Characteristic Discipline in Hunan University of Science and Engineering(Mathematics,Education and Electronic Science and Technology).
文摘We predicted two stable two-dimensional materials of carbon and bismuth elements,namely BiC and Bi_(2)C monolayers.The stabilities of two monolayers were examined by cohesive energy,Born criteria,first-principle MD simulations and phonon spectra,respectively.By including the spin-orbit coupling effects,the BiC monolayer is a metal and the Bi_(2)C monolayer possesses a narrow direct(indirect)band gap of 0.403(0.126)eV under the HSE06(GGA-PBE)functional.For the adsorption of CO_(2)molecules,the BiC and Bi_(2)C monolayers have three stable adsorption sites C2,T3 and T4 with the adsorption energies as-0.57,-0.51 and-0.81 eV,and the activation ability on the adsorption as T4>T3>C2.These consequences make the BiC and Bi_(2)C monolayers to be promising adsorbents to capture CO_(2)gas,the Bi_(2)C monolayer to be well photovoltaics and optoelectronics material,and the BiC monolayer to be ideal battery and electronics materials,respectively.
文摘Several macroporous polymeric adsorbents (NDA-999, XAD-8, X-5 and XAD-2) were employed in the study to adsorb phenylacetic acid from aqueous solution. Effect of salt and ambient temperature on adsorption was studied using NDA-999 adsorbent and the adsorption process conforms to Freundlich抯 model reasonably. Adsorption dynamics were conducted in batch experiments in order to make clear the mechanism of adsorption process. It is proved that the squared driving force mass transfer model can be adopted to elucidate the process. The treatment process of industrial wastewater containing high strength of phenylacetic acid was proposed for cleaner production of phenylacetic acid.
基金Supported by the Science and Technology Planning Project of Guangdong(2006A36701004)the Basic Research Program of the Ministry of Environmental Protection(zx_200910_02)
文摘The carbonaceous adsorbent was prepared from mixtures of dewatered sludge and sawdust with enhanced ZnCl2 chemical activation.Characteristics of the adsorbent were studied using scanning electron microscope(SEM) ,Fourier transform infrared spectroscopy(FT-IR) ,and adsorption of nitrogen.The surface analysis showed that the carbonaceous adsorbent had good specific surface and porosity(394 m 2 ·g-1of BET surface,0.12 and 0.10 ml·g-1of microporous and mesoporous volume,respectively) .The oxygen functional groups such as OH,C O and C O were found on the surface by FTIR and XPS(X-ray photoelectron spectroscopy) .The adsorption of elemental mercury(Hg0) on the carbonaceous adsorbent was studied in a fixed bed reactor.The dynamic adsorption capacity of carbonaceous adsorbent increased with influent mercury concentration,from 23.6μg·g-1at 12.58μg·m-3to 87.9μg·g-1at 72.50μg·m-3,and decreased as the adsorption temperature increased,from 246 μg·g-1 at 25°C to 61.3μg·g-1 at 140°C,when dry nitrogen was used as the carrier gas.The carbonaceous adsorbent presented higher dynamic adsorption capacity than activated carbon,which was 81.2μg·g-1and 53.8μg·g-1respectively.The adsorption data were fitted to the Langmuir adsorption model.The physical and chemical adsorption were identified on the adsorbent.
