Petroleum contamination is considered as a major risk to the health of humans and environment.Biochars as low-cost and eco-friendly carbon materials,have been widely used for the removal of petroleum hydrocarbon in th...Petroleum contamination is considered as a major risk to the health of humans and environment.Biochars as low-cost and eco-friendly carbon materials,have been widely used for the removal of petroleum hydrocarbon in the environment.The purpose of this paper is to review the performance,mechanisms,and potential environmental toxicity of biochar,modified biochar and its integration use with other materials in petroleum contaminated soil and water.Specifically,the use of biochar in oil-contaminated water and soil as well as the factors that could influence the removal ability of biochar were systematically evaluated.In addition,the modification and integrated use of biochar for improving the removal efficiency were summarized from the aspects of sorption,biodegradation,chemical degradation,and reusability.Moreover,the functional impacts and associated ecotoxicity of pristine and modified biochars in various environments were demonstrated.Finally,some shortcoming of current approaches,and future research needs were provided for the future direction and challenges of modified biochar research.Overall,this paper gain insight into biochar application in petroleum remediation from the perspectives of performance enhancement and environmental sustainability.展开更多
The Yellow River sediment(YRS)is an important potential soil resource for the mine land reclamation and ecological restoration in the arid regions of northern China.However,it has the shortcomings of poor water-holdin...The Yellow River sediment(YRS)is an important potential soil resource for the mine land reclamation and ecological restoration in the arid regions of northern China.However,it has the shortcomings of poor water-holding capacity and needs to be modified urgently.Therefore,two types of biochar,namely rice husk biochar(RHB)and coconut shell biochar(CSB),were utilized in this study to modify the YRS and compared with rice husk ash(RHA).Some engineering properties of the modified YRS(MYRS),including pore structure,water retention,permeability,and vegetation performance,were investigated by considering the effects of biochar types and dosages.Results showed that the addition of the three materials decreased the bulk density of the YRS and increased the volume of extremely micro pore(d<0.3µm),as well as the effective porosity and capillary porosity,thus contributed to an increase in the water-holding capacity of the sediment.Among the three conditioners,RHB is optimal choice for improving the water-holding capacity of YRS.Furthermore,the effect becomes more pronounced with increasing application rates.With the addition of the three materials,the permeability coefficients of MYRS gradually decreased,while the water retention rate during evaporation significantly increased.The pot experiment showed that the three conditioners all had significant promoting effect on the growth of oats.In particular,compared to plain soil,the total biomass of oats grown for 21 days increased by 17.46%,32.14%,and 49.60%after adding 2%,4%,and 8%RHB,respectively.This study introduces a new approach for using YRS as planting soil in arid and semi-arid areas of China to facilitate mine ecological restoration.展开更多
Bi Chen1,2,Hong Zeng2,Fan Yang2,Yafei Yang2,3,Zhi Qiao1,Xiaoli Zhao4,Li Wang2 and Fengchang Wu1,4*Waste activated sludge(WAS)is attracting attention for its energy and resource potential.Anaerobic digestion(AD)can be ...Bi Chen1,2,Hong Zeng2,Fan Yang2,Yafei Yang2,3,Zhi Qiao1,Xiaoli Zhao4,Li Wang2 and Fengchang Wu1,4*Waste activated sludge(WAS)is attracting attention for its energy and resource potential.Anaerobic digestion(AD)can be used to efficiently recover energy resources and stabilize pollutants in WAS,with biochar emerging as an ideal additive to boost this process.However,the low abundance of surface functional groups and small pore structure of raw biochar may limit its performance in the AD of WAS.These limitations can be overcome by using functional biochar.In this review,the preparation and modification methods for functional biochar and its role in the AD of WAS are systematically summarized and discussed.Notably,the role of functional biochar in electron transfer,buffering effects,microbial immobilization,alleviation of inhibitory effects,and functional microbial modulation are analyzed.Additionally,the impacts of biochar on digestate utilization,pollutant removal,and carbon fixation are discussed.Special attention is given to functional biochar for its ability to promote circular economy and carbon neutrality.Finally,future perspectives on the use of functional biochar in the AD of WAS are presented.The aim of this review is to provide insights into the application of functional biochar in the AD of WAS from the perspective of performance improvement,resource utilization,and circular economy.展开更多
Surface functionalization or modification to introduce more oxygen-containing functional groups to biochar is an effective strategy for tuning the physicochemical properties and promoting follow-up applications.In thi...Surface functionalization or modification to introduce more oxygen-containing functional groups to biochar is an effective strategy for tuning the physicochemical properties and promoting follow-up applications.In this study,non-thermal plasma was applied for biochar surface carving before being used in contaminant removal and energy storage applications.The results showed that even a low dose of plasma exposure could introduce a high number density of oxygen-functional groups and enhance the hydrophilicity and metal affinity of the pristine biochar.The plasma-treated biochar enabled a faster metal-adsorption rate and a 40%higher maximum adsorption capacity of heavy metal ion Pb^(2+).Moreover,to add more functionality to biochar surface,biochar with and without plasma pre-treatment was activated by KOH at a temperature of 800℃.Using the same amount of KOH,the plasma treatment resulted in an activated carbon product with the larger BET surface area and pore volume.The performance of the treated activated carbon as a supercapacitor electrode was also substantially improved by>30%.This study may provide guidelines for enhancing the surface functionality and application performances of biochar using non-thermal-based techniques.展开更多
In recent years,due to the broad application of biochars,the preparation,environmental behavior and aging processes of biochars have attracted wide attention globally,especially the modification of biochars.However,mo...In recent years,due to the broad application of biochars,the preparation,environmental behavior and aging processes of biochars have attracted wide attention globally,especially the modification of biochars.However,most of the studies only consider the improvement of biochar properties right after the modification,but neglect a complete evaluation of the long-term stability and eco-toxicity of these newly developed materials after entering the environment.With the development and utilization of biochars,engineered biochars(EngBCs)will soon enter the market,but its environmental risk still remains unclear.The literature does not provide adequate information on how aging of EngBCs will affect their properties,and indirectly impact the properties of soils(cycle of elements and organic matter).Therefore,this review paper summarizes the aging process and environmental risk of biochars,aiming at better understanding the interactions between EngBCs and soil components or pollutants.More importantly,this review is to point out the contradictory speculations of environmental behavior of EngBCs studied at the present stage.Due to the modification,the EngBCs stability may be significantly reduced.However,the formation of functional group on EngBCs will enhance their interaction with soil minerals to form biochars-mineral complex,and thus EngBCs could be protected.The impacts of EngBCs after entering the environment are also ambiguous.Therefore,understanding EngBCs environmental behavior is critical,which is helpful to reduce the potential risk and to produce EngBCs following the rule of sustainable development and safety to the environment.展开更多
Modified biochar with higher electron transport and adsorption capabilities could significantly improve the performance of anaerobic ammonia oxidation(anammox).However,there are few related investigations on the reinf...Modified biochar with higher electron transport and adsorption capabilities could significantly improve the performance of anaerobic ammonia oxidation(anammox).However,there are few related investigations on the reinforcement of anammox through iron-modified Enteromorpha prolifera biochar(IMEPB).In this study,with the addition of the IMEPB in the anammox system,the enhancing process of anammox performance was studied,the improving feasibility of anammox was evaluated,and the reinforcing mechanism of anammox was elucidated.The results showed that the optimal iron−charcoal ratio(Fe:C)and IMEPB dosage were 1:10 and 10 g L^(−1),respectively.Under the optimal conditions,when the nitrogen loading rate gradually increased to 0.557(kg m^(−3) day^(−1)),the nitrogen removal efficiency and nitrogen removal rate of the anammox process supplemented with IMEPB increased by 11%,and the specific anammox activity increased by 23.8%.Compared with the control,the secretion of extracellular polymeric substances(EPS)of anammox bacteria supplemented IMEPB increased by 24.4%,greatly improving the stability of the anammox system.Meanwhile,EPS secretion further promoted the microbial activity of anammox bacteria,achieving a 19%increase in the abundance of Candidatus Brocadia.These findings demonstrate the potential mechanism of IMEPB in improving anammox,provide new insights into recycling E.prolifera,and provide a novel reinforcement strategy for anammox.In the future,adding IMEPB may be a vital measure for the practical application of anammox in coastal areas.展开更多
Municipal wastewater sludge can be pyrolyzed as biochars to better use nutrients and stabilize carbon compared with other typical technologies,such as landfill and incineration.However,sludge-derived biochars might co...Municipal wastewater sludge can be pyrolyzed as biochars to better use nutrients and stabilize carbon compared with other typical technologies,such as landfill and incineration.However,sludge-derived biochars might contain large amounts of potentially toxic elements(PTEs),such as Zn,Cu,Cr,Ni,Pb,and As.The stability of PTEs in biochars might be improved by higher pyrolytic temperatures,which can be further improved by different modifications.Herein,PO4-modification at 300°C and Cl-modification at 700°C were carried out,respectively,to enhance the stability of PTEs.Various leaching tests have been performed to assess the stability of PTEs in biochars,including the synthetic precipitation leaching procedure(SPLP),toxicity characteristic leaching procedure(TCLP),diethylenetriamine pentaacetate(DTPA)extraction,and in vitro simple bioaccessibility extraction test(SBET).The morphological structure,elemental mapping,and mineral formation of the pristine and modified biochars were studied by scanning electron microscopy–energy-dispersive X-ray spectroscopy(SEM–EDS)and X-ray diffraction(XRD).Our results suggested that the leachability,mobility,plant-availability,and bioaccessibility of most PTEs were decreased by pyrolysis,yet the total contents of PTEs were elevated,especially at 700°C.Generally,modification by phosphates and MgCl2 enhanced the stability of PTEs in biochars.Nevertheless,it should be noted that higher bioaccessibility of PTEs was observed in biochars of P-modification than Cl-modification,which is associated with the dissolution of phosphate precipitates under acidic conditions(pH<2).Additionally,Cl-modification leads to higher plant-available Zn and Cu and bioaccessible Zn compared with the unmodified biochar produced at 700°C.展开更多
Various human activities have led to multiple contamination of natural water systems.The present study investigated the effect of a novel multifunctional biochar to treat nutrients,oil,and harmful algae in water.Speci...Various human activities have led to multiple contamination of natural water systems.The present study investigated the effect of a novel multifunctional biochar to treat nutrients,oil,and harmful algae in water.Specifically,magnesium(Mg)and biosurfactant rhamnolipid(RL)were incorporated into biochar,including Mg-biochar,RL-biochar,and Mg-RL-biochar.Their adsorption efficiency on phosphate and total petroleum hydrocarbons(TPH)was evaluated in separate batch studies.Also,the inhibition effect of RL-modified biochars on cyanobacteria was investigated.The results showed that Mg-impregnated biochar showed high adsorption capacity on phosphate(118 mg g^(−1)),while RLmodified biochar significantly reduced TPH(especially aromatic and light aliphatic fraction)with adsorption capacity of 44.4 mg g^(−1).The inhibition effects of biochar composites on algae in water without contaminants were in order of Mg-RL-biochar>RL-biochar>biochar with biomass reduction ranging 61-64%.Overall,Mg-RL-biochar was suggested based on this study due to its ability to remove PO_(4)^(3)−and TPH,and inhibit the growth of toxic algae.展开更多
基金supported by the Yunnan Fundamental Research Projects(No.202201BE070001-043)the Yunnan Provincial Excellent Young Scientists Fund(No.202201AW070006)+1 种基金USDA-NRCS(No.NR217217XXXXG004)the USDA National Institute of Food and Agriculture Hatch Project(No.7003969)。
文摘Petroleum contamination is considered as a major risk to the health of humans and environment.Biochars as low-cost and eco-friendly carbon materials,have been widely used for the removal of petroleum hydrocarbon in the environment.The purpose of this paper is to review the performance,mechanisms,and potential environmental toxicity of biochar,modified biochar and its integration use with other materials in petroleum contaminated soil and water.Specifically,the use of biochar in oil-contaminated water and soil as well as the factors that could influence the removal ability of biochar were systematically evaluated.In addition,the modification and integrated use of biochar for improving the removal efficiency were summarized from the aspects of sorption,biodegradation,chemical degradation,and reusability.Moreover,the functional impacts and associated ecotoxicity of pristine and modified biochars in various environments were demonstrated.Finally,some shortcoming of current approaches,and future research needs were provided for the future direction and challenges of modified biochar research.Overall,this paper gain insight into biochar application in petroleum remediation from the perspectives of performance enhancement and environmental sustainability.
基金supported by the Major Science And Technology Program of Inner Mongolia(Grant No.2021ZD0007)National Natural Science Foundation of China(Grant Nos.52209134 and 52322810)+1 种基金Natural Science Foundation of Hubei Province for Distinguished Young Scholars(No.2023AFA080)Youth Science Foundation of Jiangsu Province of China(Grant No.BK20220230).
文摘The Yellow River sediment(YRS)is an important potential soil resource for the mine land reclamation and ecological restoration in the arid regions of northern China.However,it has the shortcomings of poor water-holding capacity and needs to be modified urgently.Therefore,two types of biochar,namely rice husk biochar(RHB)and coconut shell biochar(CSB),were utilized in this study to modify the YRS and compared with rice husk ash(RHA).Some engineering properties of the modified YRS(MYRS),including pore structure,water retention,permeability,and vegetation performance,were investigated by considering the effects of biochar types and dosages.Results showed that the addition of the three materials decreased the bulk density of the YRS and increased the volume of extremely micro pore(d<0.3µm),as well as the effective porosity and capillary porosity,thus contributed to an increase in the water-holding capacity of the sediment.Among the three conditioners,RHB is optimal choice for improving the water-holding capacity of YRS.Furthermore,the effect becomes more pronounced with increasing application rates.With the addition of the three materials,the permeability coefficients of MYRS gradually decreased,while the water retention rate during evaporation significantly increased.The pot experiment showed that the three conditioners all had significant promoting effect on the growth of oats.In particular,compared to plain soil,the total biomass of oats grown for 21 days increased by 17.46%,32.14%,and 49.60%after adding 2%,4%,and 8%RHB,respectively.This study introduces a new approach for using YRS as planting soil in arid and semi-arid areas of China to facilitate mine ecological restoration.
基金the Guizhou Provincial Science and Technology Major Program(Qian Ke He[2024]006).
文摘Bi Chen1,2,Hong Zeng2,Fan Yang2,Yafei Yang2,3,Zhi Qiao1,Xiaoli Zhao4,Li Wang2 and Fengchang Wu1,4*Waste activated sludge(WAS)is attracting attention for its energy and resource potential.Anaerobic digestion(AD)can be used to efficiently recover energy resources and stabilize pollutants in WAS,with biochar emerging as an ideal additive to boost this process.However,the low abundance of surface functional groups and small pore structure of raw biochar may limit its performance in the AD of WAS.These limitations can be overcome by using functional biochar.In this review,the preparation and modification methods for functional biochar and its role in the AD of WAS are systematically summarized and discussed.Notably,the role of functional biochar in electron transfer,buffering effects,microbial immobilization,alleviation of inhibitory effects,and functional microbial modulation are analyzed.Additionally,the impacts of biochar on digestate utilization,pollutant removal,and carbon fixation are discussed.Special attention is given to functional biochar for its ability to promote circular economy and carbon neutrality.Finally,future perspectives on the use of functional biochar in the AD of WAS are presented.The aim of this review is to provide insights into the application of functional biochar in the AD of WAS from the perspective of performance improvement,resource utilization,and circular economy.
基金supported by the National Natural Science Foundation of China(Grant No.52007023)the Natural Science Foundation of Liaoning Province,China(Grant Nos.2020-BS-073,2019-ZD-0160)+2 种基金the China Postdoctoral Science Foundation(Grant No.2019M661107)the Dalian Maritime University basic scientific research business expenses key scientific research cultivation project(Grant No.3132020371)the Fundamental Research Funds for the Central Universities(Grant No.3132021159).
文摘Surface functionalization or modification to introduce more oxygen-containing functional groups to biochar is an effective strategy for tuning the physicochemical properties and promoting follow-up applications.In this study,non-thermal plasma was applied for biochar surface carving before being used in contaminant removal and energy storage applications.The results showed that even a low dose of plasma exposure could introduce a high number density of oxygen-functional groups and enhance the hydrophilicity and metal affinity of the pristine biochar.The plasma-treated biochar enabled a faster metal-adsorption rate and a 40%higher maximum adsorption capacity of heavy metal ion Pb^(2+).Moreover,to add more functionality to biochar surface,biochar with and without plasma pre-treatment was activated by KOH at a temperature of 800℃.Using the same amount of KOH,the plasma treatment resulted in an activated carbon product with the larger BET surface area and pore volume.The performance of the treated activated carbon as a supercapacitor electrode was also substantially improved by>30%.This study may provide guidelines for enhancing the surface functionality and application performances of biochar using non-thermal-based techniques.
基金This research was supported by National Natural Science Foundation of China(41725016,U1602231,41807377 and 41673098)a joint fund between NSFC-NCN(4181101459)Yunnan Provincial Scientific Innovation Team of Soil Environment and Ecological Safety(2019HC008).
文摘In recent years,due to the broad application of biochars,the preparation,environmental behavior and aging processes of biochars have attracted wide attention globally,especially the modification of biochars.However,most of the studies only consider the improvement of biochar properties right after the modification,but neglect a complete evaluation of the long-term stability and eco-toxicity of these newly developed materials after entering the environment.With the development and utilization of biochars,engineered biochars(EngBCs)will soon enter the market,but its environmental risk still remains unclear.The literature does not provide adequate information on how aging of EngBCs will affect their properties,and indirectly impact the properties of soils(cycle of elements and organic matter).Therefore,this review paper summarizes the aging process and environmental risk of biochars,aiming at better understanding the interactions between EngBCs and soil components or pollutants.More importantly,this review is to point out the contradictory speculations of environmental behavior of EngBCs studied at the present stage.Due to the modification,the EngBCs stability may be significantly reduced.However,the formation of functional group on EngBCs will enhance their interaction with soil minerals to form biochars-mineral complex,and thus EngBCs could be protected.The impacts of EngBCs after entering the environment are also ambiguous.Therefore,understanding EngBCs environmental behavior is critical,which is helpful to reduce the potential risk and to produce EngBCs following the rule of sustainable development and safety to the environment.
基金National Natural Science Foundation of China(Grant Number 51978348).
文摘Modified biochar with higher electron transport and adsorption capabilities could significantly improve the performance of anaerobic ammonia oxidation(anammox).However,there are few related investigations on the reinforcement of anammox through iron-modified Enteromorpha prolifera biochar(IMEPB).In this study,with the addition of the IMEPB in the anammox system,the enhancing process of anammox performance was studied,the improving feasibility of anammox was evaluated,and the reinforcing mechanism of anammox was elucidated.The results showed that the optimal iron−charcoal ratio(Fe:C)and IMEPB dosage were 1:10 and 10 g L^(−1),respectively.Under the optimal conditions,when the nitrogen loading rate gradually increased to 0.557(kg m^(−3) day^(−1)),the nitrogen removal efficiency and nitrogen removal rate of the anammox process supplemented with IMEPB increased by 11%,and the specific anammox activity increased by 23.8%.Compared with the control,the secretion of extracellular polymeric substances(EPS)of anammox bacteria supplemented IMEPB increased by 24.4%,greatly improving the stability of the anammox system.Meanwhile,EPS secretion further promoted the microbial activity of anammox bacteria,achieving a 19%increase in the abundance of Candidatus Brocadia.These findings demonstrate the potential mechanism of IMEPB in improving anammox,provide new insights into recycling E.prolifera,and provide a novel reinforcement strategy for anammox.In the future,adding IMEPB may be a vital measure for the practical application of anammox in coastal areas.
基金the financial supports by the National Natural Science Foundation for Young Scientists of China(No.42007142)the Guangdong Basic and Applied Basic Research Foundation(No.2019A1515110927)the Key Scientific and Technological Project of Foshan City(No.2120001008392).
文摘Municipal wastewater sludge can be pyrolyzed as biochars to better use nutrients and stabilize carbon compared with other typical technologies,such as landfill and incineration.However,sludge-derived biochars might contain large amounts of potentially toxic elements(PTEs),such as Zn,Cu,Cr,Ni,Pb,and As.The stability of PTEs in biochars might be improved by higher pyrolytic temperatures,which can be further improved by different modifications.Herein,PO4-modification at 300°C and Cl-modification at 700°C were carried out,respectively,to enhance the stability of PTEs.Various leaching tests have been performed to assess the stability of PTEs in biochars,including the synthetic precipitation leaching procedure(SPLP),toxicity characteristic leaching procedure(TCLP),diethylenetriamine pentaacetate(DTPA)extraction,and in vitro simple bioaccessibility extraction test(SBET).The morphological structure,elemental mapping,and mineral formation of the pristine and modified biochars were studied by scanning electron microscopy–energy-dispersive X-ray spectroscopy(SEM–EDS)and X-ray diffraction(XRD).Our results suggested that the leachability,mobility,plant-availability,and bioaccessibility of most PTEs were decreased by pyrolysis,yet the total contents of PTEs were elevated,especially at 700°C.Generally,modification by phosphates and MgCl2 enhanced the stability of PTEs in biochars.Nevertheless,it should be noted that higher bioaccessibility of PTEs was observed in biochars of P-modification than Cl-modification,which is associated with the dissolution of phosphate precipitates under acidic conditions(pH<2).Additionally,Cl-modification leads to higher plant-available Zn and Cu and bioaccessible Zn compared with the unmodified biochar produced at 700°C.
基金Yunnan Fundamental Research Projects(Grant#202201BE070001-043)National Natural Science Foundation of China(Grant#41967039)+1 种基金Yunnan Provincial Excellent Young Scientists Fund(Grant#202201AW070006)Yunnan Foundation Research Projects(202301AU070074)。
文摘Various human activities have led to multiple contamination of natural water systems.The present study investigated the effect of a novel multifunctional biochar to treat nutrients,oil,and harmful algae in water.Specifically,magnesium(Mg)and biosurfactant rhamnolipid(RL)were incorporated into biochar,including Mg-biochar,RL-biochar,and Mg-RL-biochar.Their adsorption efficiency on phosphate and total petroleum hydrocarbons(TPH)was evaluated in separate batch studies.Also,the inhibition effect of RL-modified biochars on cyanobacteria was investigated.The results showed that Mg-impregnated biochar showed high adsorption capacity on phosphate(118 mg g^(−1)),while RLmodified biochar significantly reduced TPH(especially aromatic and light aliphatic fraction)with adsorption capacity of 44.4 mg g^(−1).The inhibition effects of biochar composites on algae in water without contaminants were in order of Mg-RL-biochar>RL-biochar>biochar with biomass reduction ranging 61-64%.Overall,Mg-RL-biochar was suggested based on this study due to its ability to remove PO_(4)^(3)−and TPH,and inhibit the growth of toxic algae.
