资源类型

期刊论文 8

年份

2022 1

2020 1

2017 2

2015 2

2013 1

2012 1

关键词

检索范围：

排序： 展示方式：

Competition for electrons between reductive dechlorination and denitrification

Lifeng Cao, Weihua Sun, Yuting Zhang, Shimin Feng, Jinyun Dong, Yongming Zhang, Bruce E. Rittmann

《环境科学与工程前沿（英文）》 2017年 第11卷 第6期 doi: 10.1007/s11783-017-0959-x

摘要： It is common that 2,4,6-trichlorophenol (TCP) coexists with nitrate or nitrite in industrial wastewaters. In this work, simultaneous reductive dechlorination of TCP and denitrification of nitrate or nitrite competed for electron donor, which led to their mutual inhibition. All inhibitions could be relieved to a certain degree by augmenting an organic electron donor, but the impact of the added electron donor was strongest for TCP. For simultaneous reduction of TCP together with nitrate, TCP’s removal rate value increased 75% and 150%, respectively, when added glucose was increased from 0.4 mmol·L to 0.5 mmol·L and to 0.76 mmol·L . For comparison, the removal rate for nitrate increased by only 25% and 114% for the same added glucose. The relationship between their initial biodegradation rates versus their initial concentrations could be represented well with the Monod model, which quantified their half-maximum-rate concentration ( value), and values for TCP, nitrate, and nitrite were larger with simultaneous reduction than independent reduction. The increases in are further evidence that competition for the electron donor led to mutual inhibition. For bioremediation of wastewater containing TCP and oxidized nitrogen, both reduction reactions should proceed more rapidly if the oxidized nitrogen is nitrite instead of nitrate and if readily biodegradable electron acceptor is augmented.

关键词： Competition for electrons     Denitrification     Reductive dechlorination     Bioremediation     Nitrate     2     4     6-trichlorophenol    

HTML PDF 收藏

Development and characterization of an anaerobic microcosm for reductive dechlorination of PCBs

Dawei Liang, Shanquan Wang

《环境科学与工程前沿（英文）》 2017年 第11卷 第6期 doi: 10.1007/s11783-017-0939-1

摘要： The toxic and recalcitrant polychlorinated biphenyls (PCBs) adversely affect human and biota by bioaccumulation and biomagnification through food chain. In this study, an anaerobic microcosm was developed to extensively dechlorinate hexa- and hepta-CBs in Aroclor 1260. After 4 months of incubation in defined mineral salts medium amended PCBs (70 mmol·L ) and lactate (10 mmol·L ), the culture dechlorinated hexa-CBs from 40.2% to 8.7% and hepta-CBs 33.6% to 11.6%, with dechlorination efficiencies of 78.3% and 65.5%, respectively (all in moL ratio). This dechlorination process led to tetra-CBs (46.4%) as the predominant dechlorination products, followed by penta- (22.1%) and tri-CBs (5.4%). The number of chlorines per biphenyl decreased from 2.50 to 1.41. Results of quantitative real-time PCR show that cells increased from 2.39 × 10 ±0.5 × 10 to 4.99 × 10 ±0.32 × 10 copies mL after 120 days of incubation, suggesting that play a major role in reductive dechlorination of PCBs. This study could prove the feasibility of anaerobic reductive culture enrichment for the dehalogenation of highly chlorinated PCBs, which is prior to be applied for in situ bioremediation of notorious halogenated compounds.

关键词： Polychlorinated biphenyls (PCBs)     Microbial reductive dechlorination     Dehalococcoides     Pathway    

HTML PDF 收藏

Efficient dechlorination of 2,4-dichlorophenol in an aqueous media with a mild pH using a Pd/TiO

Jiangkun DU,Jianguo BAO,Wei HU

《环境科学与工程前沿（英文）》 2015年 第9卷 第5期   页码 919-928 doi: 10.1007/s11783-015-0794-x

摘要： In this study, palladium-loaded titania nanotubes was fabricated on a titanium plate (Pd/TiO NTs/Ti) for efficient electrodechlorination of 2,4-chlorophenol with a mild pH condition. The nature of Pd/TiO NTs/Ti electrodes was characterized by field-emission scanning electron microscope (FESEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and cyclic voltammetry (CV) techniques. The characterization results indicated the generation of Pd nanoparticles which were evenly dispersed on titania nanotubes arrays on the Pd/TiO NTs/Ti surface. An effective degradation efficiency of up to 91% was achieved within 60 min at cathode potential of −0.7 V ( SCE) and initial pH of 5.5. The effects of the applied cathode potential and initial pH on the degradation efficiency were studied. A near neutral condition was more favorable since very low and very high pHs were not conducive to the dechlorination process. Furthermore, the intermediates analysis showed that the Pd/TiO NTs/Ti electrode could completely remove chlorine from 2, 4-dichlorophenol since only phenol was detected as the byproduct and the concentration of released chlorine ions indicated near-complete dechlorination. This work presents a good alternative technique for eliminating persistent chlorophenols in polluted wastewater without maintaining strong acidic environment.

关键词： Pd/TiO2NTs/Ti cathode     chlorophenols     electrocatalytic dechlorination     wastewater treatment    

HTML PDF 收藏

A thermodynamic study of the removal of HCl and H

Joseph LEE, Bo FENG

《化学科学与工程前沿（英文）》 2012年 第6卷 第1期   页码 67-83 doi: 10.1007/s11705-011-1162-4

摘要： Advanced integrated-gasification combined-cycle (IGCC) and integrated-gasification fuel cell (IFGC) systems require high-temperature sorbents that are capable of removing hydrogen chloride and hydrogen sulfide from coal derived gases to very low levels. HCl and H S are highly reactive, corrosive, and toxic gases that must be removed to meet stringent environmental regulations, to protect power generation equipment and to control the emissions of contaminants. The thermodynamic behavior of 13 sorbents for the removal of HCl and H S under various conditions including: initial toxic gas concentration (1–10000 ppm), operating pressure (0.1–11 Mpa), temperature (300 K–1500 K), and the presence of H O were investigated. The correlation between HCl and H S was also examined. Thermodynamic calculations were carried out for the reactions of the 13 sorbents using a FactSage 5.2 software package based on free energy minimization. The sorbents, Na CO , NaHCO , K CO , and CaO are capable of completely removing chlorine at high temperatures (up to ~1240 K) and at high pressures. Water vapor did not have any significant effects on the dechlorination capability of the sorbents. Nine of the sorbents namely; Cu O, Na CO , NaHCO , K CO , CaO, ZnO, MnO, FeO, and PbO, were determined to have great potential as desulfurization sorbents. Cu O and ZnO had the best performance in terms of the optimum operating temperature. The addition of water vapor to the reactant gas produces a slightly detrimental effect on most of the sorbents, but FeO exhibited the worst performance with a reduction in the maximum operating temperature of about 428 K. The dechlorination performance of the alkali sorbents was not affected by the presence of H S in the reactions. However, the desulfurization capability of some sorbents was greatly affected by the presence of HCl. Particularly, the performance of Cu O was significantly reduced when HCl was present, but the performance of FeO improved remarkably. The thermodynamic results gathered are valuable for the developments of better sorbents.

关键词： syngas cleaning     sorbent     desulfurization     dechlorination    

HTML PDF 收藏

Dechlorination of 2,2′,4,4′,5,5′-hexachlorobiphenyl by thermal reaction with activated carbon-supported

Yifei SUN, Xin FU, Wei QIAO, Wei WANG, Tianle ZHU, Xinghua LI

《环境科学与工程前沿（英文）》 2013年 第7卷 第6期   页码 827-832 doi: 10.1007/s11783-013-0543-y

摘要： Activated carbon (AC)-supported copper or zinc made from ion exchange resin (IRCu-C and IRZn-C) have an increased metal load of 557.3 mg?g and 502.8 mg?g compared to those prepared by the traditional method involving impregnation with AC and copper (II) citrate or zinc citrate solution (LaCu-C and LaZn-C) of 12.9 mg?g and 46.0 mg?g respectively. When applied to decompose 2,2′,4,4′,5,5′-hexachlorobiphenyl at 250 °C, IRCu-C achieved higher activity of 99.0% decomposition efficiency than LaCu-C of 84.7%, IRZn-C of 90.5% and LaZn-C of 62.7%. When the reaction temperature rose to 350 °C, all the four kinds of reactants can decompose PCB-153 with efficiency above 90%. Further, X-ray photoelectron spectroscopy characterization of IRCu-C before and after the reaction indicated transformation of 19.1% of Cu atoms into Cu , illustrating that Cu is the active ingredient or electron donor promoting the decomposition of PCB-153. The mechanism underlying this process differs from a traditional H donor. However, there is no significant change on the surface of IRZn-C before and after the reaction, suggesting that Zn acts as catalyst during the process of PCB-153 decomposition.

关键词： polychlorinated biphenyls     activated carbon-supported copper or zinc     dechlorination     electron donor    

HTML PDF 收藏

Enhanced 4-chlorophenol biodegradation by integrating FeO nanoparticles into an anaerobic reactor: Long-term performance and underlying mechanism

《环境科学与工程前沿（英文）》 2022年 第16卷 第8期 doi: 10.1007/s11783-022-1519-6

摘要：

• 4-chlorophenol biodegradation could be enhanced in Fe2O3 coupled anaerobic system.

关键词： Dechlorination     Fe2O3 nanoparticles     Electron transfer     Microbial community    

HTML PDF 收藏

Dechlorination of dichlorodiphenyltrichloroethane (DDT) by Fe/Pd bimetallic nanoparticles: Comparison

Kubra Ulucan-Altuntas, Eyup Debik

《环境科学与工程前沿（英文）》 2020年 第14卷 第1期 doi: 10.1007/s11783-019-1196-2

摘要： DDT undergoes dechlorination via Fe/Pd bimetallic nanoparticle. The oxidation effect of nZVI on DDT is greatly improved when Pd is dopped. The highest concentration to be treated under cancerogenesis limit was 110 mg/L. The dechlorination of DDT is more like to DDE via Fe/Pd but to DDD via nZVI. Degradation products concentrations are lowered via Fe/Pd when compared with nZVI. In this study, the bimetallic Fe/Pd nanoparticle was synthesized using the catalytic element palladium to increase the effect of nano zero valent iron (nZVI), in the light of the information obtained from our previous study, in which the nZVI synthesis method was modified. Dichlorodiphenyltrichloroethane (DDT), one of the most widely used persistent organic pollutant pesticides in the world, was investigated in terms of its degradation by Fe/Pd nanoparticles and the difference with nZVI was determined. During the study, the Fe/Pd concentration, initial DDT concentration, and contact time were selected as variables affecting the treatment. The highest possible initial DDT concentration for the treatment with Fe/Pd bimetallic nanoparticle was investigated to obtain the DDT effluent concentration below the carcinogenesis limit, 0.23 µg/L. The highest concentration that could be treated was found to be 109.95 mg/L with Fe/Pd. It was found that 44.3 min of contact time and 550 mg/L Fe/Pd concentration were needed to achieve this treatment.

关键词： Persistent organic pollutants     nZVI     Bimetallic nanoparticle     Organochlorine pesticides     DDT    

HTML PDF 收藏

Iron-carbon composite microspheres prepared through a facile aerosol-based process for the simultaneous adsorption and reduction of chlorinated hydrocarbons

Bhanukiran SUNKARA,Yang SU,Jingjing ZHAN,Jibao HE,Gary L. MCPHERSON,Vijay T. JOHN

《环境科学与工程前沿（英文）》 2015年 第9卷 第5期   页码 939-947 doi: 10.1007/s11783-015-0807-9

摘要： Iron-carbon (Fe-C) composite microspheres prepared through a facile aerosol-based process are effective remediation agents for the simultaneous adsorption and reduction of chlorinated hydrocarbons. Complete dechlorination was achieved for the class of chlorinated ethenes that include tetrachloroethylene (PCE), trichloroethylene (TCE), and -1,2-dicloroethylene (c-DCE, t-DCE), 1,1-dichloroethylene (1,1-DCE) and, vinyl chloride (VC). The Fe-C particles potentially provides multi-functionality with requisite characteristics of adsorption, reaction, and transport for the effective in situ remediation of chlorinated hydrocarbons. The carbon support immobilizes the ferromagnetic iron nanoparticles onto its surface, thereby inhibiting aggregation. The adsorptive nature of the carbon support prevents the release of toxic intermediates such as the dichloroethylenes and vinyl chloride. The adsorption of chlorinated ethenes on the Fe-C composites is higher (>80%) than that of humic acid (<35%) and comparable to adsorption on commercial activated carbons (>90%). The aerosol-based process is an efficient method to prepare adsorptive-reactive composite particles in the optimal size range for transport through the porous media and as effective targeted delivery agents for the in situ remediation of soil and groundwater contaminants.

关键词： chlorinated ethene     iron-carbon     aerosol     adsorption     reductive dechlorination    

HTML PDF 收藏

标题 作者 时间 类型 操作

Competition for electrons between reductive dechlorination and denitrification

Lifeng Cao, Weihua Sun, Yuting Zhang, Shimin Feng, Jinyun Dong, Yongming Zhang, Bruce E. Rittmann

期刊论文

Development and characterization of an anaerobic microcosm for reductive dechlorination of PCBs

Dawei Liang, Shanquan Wang

期刊论文

Efficient dechlorination of 2,4-dichlorophenol in an aqueous media with a mild pH using a Pd/TiO

Jiangkun DU,Jianguo BAO,Wei HU

期刊论文

A thermodynamic study of the removal of HCl and H

Joseph LEE, Bo FENG

期刊论文

Dechlorination of 2,2′,4,4′,5,5′-hexachlorobiphenyl by thermal reaction with activated carbon-supported

Yifei SUN, Xin FU, Wei QIAO, Wei WANG, Tianle ZHU, Xinghua LI

期刊论文

Enhanced 4-chlorophenol biodegradation by integrating FeO nanoparticles into an anaerobic reactor: Long-term performance and underlying mechanism

期刊论文

Dechlorination of dichlorodiphenyltrichloroethane (DDT) by Fe/Pd bimetallic nanoparticles: Comparison

Kubra Ulucan-Altuntas, Eyup Debik

期刊论文

Iron-carbon composite microspheres prepared through a facile aerosol-based process for the simultaneous adsorption and reduction of chlorinated hydrocarbons

Bhanukiran SUNKARA,Yang SU,Jingjing ZHAN,Jibao HE,Gary L. MCPHERSON,Vijay T. JOHN

期刊论文