RESEARCH ON CHEMICAL INTERMEDIATES
·
2022
·Vol. 48
·期 11
·4459-4473
·
IF 3.134
Wei Xinyan,Fu Xiaori,Lyu Shuguang
The use of zinc dioxide (ZnO 2 ) powder as a source of H 2 O 2 in a modified Fenton reaction catalyzed with Fe(II) to destroy trichloroethylene (TCE) was investigated. The experimental results showed that the optimum molar ratio of ZnO 2 /Fe(II)/TCE in ZnO 2 /Fe(II)/TCE system was 20/20/1 with a TCE removal of up to 99.6%. TCE degradation was significantly inhibited by the low reaction temperature and influenced by the initial solution pH, in which ZnO 2 /Fe(II)/TCE system was suited for high temperature and low pH settings. Both Cl − and HCO 3 − anions showed a detrimental effect on TCE elimination with HCO 3 − being more significant. The addition of a high concentration (100 mg/L) of HA in solution inhabited TCE degradation performance, while the effect was negligible at low concentrations (1–10 mg/L). The tests with hydroxyl radical (HO·) scavengers elucidated that TCE was mainly degraded by HO· radicals in ZnO 2 /Fe(II)/TCE system. TCE degradation and the dechlorination proceeded simultaneously, but the final release of Cl − was less than the degraded TCE, indicating the occurrence of chlorinated intermediates in the reaction process. Graphical abstract
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2012
·
IF 4.531
Kaoqi Lian,Pingping Zhang,Lingmei Niu,Siyuan Bi,Shipeng Liu,Lingling Jiang,Weijun Kang
A new method was developed for determination of ketamine (KT) in urine and plasma samples by derivatization and gas chromatography–mass spectrometry. In this article, KT was first derivatized with sodium nitrite to volatile N-nitrosamines under acidic condition. Then the derivative had been identified by the mass spectra. The derivatization conditions including the amount of hydrochloric acid, the amount of sodium nitrite, reaction temperature, reaction time and the extraction reagents were optimized. Calibration curves were linear in the range of 0.04–20 μg mL −1 for KT, and the limit of detection (LOD) and limit of quantitation (LOQ) were 0.01 μg mL −1 and 0.04 μg mL −1 , respectively. The results of recovery indicated that the method had good precision and reproducibility. Compared with existing derivatization methods, this method provided a rapid, convenient, effective and low-cost way for gas chromatography method of KT quantification.
研究领域:
分析化学
·
医学检验
✓ 已验证
DOI
PubMed
高影响因子
CHEMOSPHERE
·
2017
·
IF 4.208
Cong Li,Feilong Dong,John C. Crittenden,Feng Luo,Xinbo Chen,Taotao Zhao
The kinetics and mechanisms of 17β-estradiol (E2) chlorination in water distribution systems (WDS) were studied. We examined the impacts of different factors, including pH, temperature, humic acid concentration and type, and flow velocity. The experimental results showed that the rate constants in beaker tests and WDS were described by a pseudo-first-order model. pH had the greatest impact on E2 chlorination in the beaker tests. However, temperature had the greatest impact on E2 chlorination in WDS. Mechanistic analysis of E2 chlorination showed that chlorine attacked E2 in three stages: 1) halogenation of the aromatic ring, 2) cleavage of the benzene moiety and chlorine or bromine substitution formation, and 3) formation of trihalomethanes (THMs) and halogenated acetic acids (HAAs) from phenolic intermediates through benzene ring opening with chlorine and/or bromine substitution of hydrogen on the carbon atoms. In the third stage, the concentrations of THMs and HAAs increased rapidly.
研究领域:
环境科学
·
生物学
✓ 已验证
DOI
PubMed
高影响因子
CARBON
·
2018
·
IF 7.082
Kaikai Zhang,Peng Sun,Marie Christine A.S. Faye,Yanrong Zhang
The property of biochar and its potential application toward chlorobenzene degradation were investigated in this study. The biochar was derived from rice husk and charred at 550 °C in N 2 atmosphere, which showed a significant degradation of chlorobenzene in ambient atmosphere. The results from Scanning Electron Microscope , X-Ray Diffraction and Raman Spectroscopy indicated the formation of poorly ordered graphene stacks embedded in amorphous phases on biochar. Fourier Transform Infrared Spectroscopy and Electron Paramagnetic Resonance suggested the existence of hydroquinone-quinone moieties on biochar, which could induce the generation of reactive oxygen species and promote the degradation of chlorobenzene. Furthermore, hydrogen peroxide and hydroxyl radicals were generated from the reduction of oxygen with the oxidization of phenolic hydroxyl groups on biochar, which was responsible for chlorobenzene degradation. In addition, more types of intermediate products of chlorobenzene degradation were detected in biochar system compared with conventional Fenton reaction, which could be possibly ascribed to the interfacial reaction between chlorobenzene and reactive oxygen species on biochar surface. The findings in this study would provide a new insight into the application of biochar in organic pollutant removal .
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2017
·Vol. 24
·期 23
·19031-19043
·
IF 2.741
Mubeen Ishrat,Buekens Alfons,Chen Zhiliang,Lu Shengyong,Yan Jianhua
Municipal solid waste incineration (MSWI) fly ash has been classified as hazardous waste and needs treatment in an environmentally safe manner. Mechanochemical (MC) treatment is such a detoxification method, since it destroys dioxins and solidifies heavy metals. Milling, however, also introduces supplemental metals (Fe, Ni, Cr, Mn…), following wear of both steel balls and housing. Milling moreover reduces the particle size of fly ash and disperses catalytic metal, potentially rising the reactivity of fly ash to form and destroy ‘dioxins’, i.e. polychlorinated dibenzo- p -dioxins and dibenzofurans (PCDD + PCDF or PCDD/F). To test this issue, model fly ash (MFA) samples were composed by mixing of silica, sodium chloride, and activated carbon, and doped with CuCl 2 . Then, these samples were first finely milled without any additives for 0 h (original sample), 1 h and 8 h, and the effect of milling time (and hence particle size) was investigated on the formation of polycyclic aromatic hydrocarbons (PAHs), and of polychlorinated phenols (CP), benzenes (CBz), biphenyls (PCB) and dioxins (PCDD + PCDF) during de novo tests at 300 °C for 1 h, thus simulating the conditions prevailing in the post-combustion zone of an incinerator, where dioxins are formed and destroyed. These compounds are all characterized by their rate of generation (ng/g MFA) and their signature, i.e. internal distribution over congeners as a means of gathering mechanistic indications. PAH and CBz total yield did not decrease in MC treated MFA with milling time, while total pentachlorophenol (PeCP), PCB and PCDD/F yield decreased up to 86, 94 and 97%, respectively. International Toxic Equivalents (I-TEQ) concentration decreased more than 90%, while degree of chlorination varied inconsistently for PCB and PCDD/F, and average congener patterns of PCDD/F do not vary considerably with milling time for both gas and solid phase.
研究领域:
环境科学
·
化学
✓ 已验证
DOI
PubMed
高影响因子
WATER RESEARCH
·
2020
·
IF 9.13
Ze-Chen Gao,Yi-Li Lin,Bin Xu,Ying Xia,Chen-Yan Hu,Tian-Yang Zhang,Hao Qian,Tong-Cheng Cao,Nai-Yun Gao
The effect of bromide and iodide on the transformation of humic acid (HA) and algal organic matter (AOM), and the formation of disinfection by-products (DBPs) during UV/chlorination were investigated. Experimental results indicated that the halides effectively inhibited mineralization, with multiple changes in organic molecule transformation due to differences in formation and speciation of reactive halogen species and free halogen. As a consequence, bromide and iodide also played important roles in DBP formation. The DBP yields in HA-containing water during UV/chlorination decreased in the order of iodide loaded > freshwater ≫ bromide loaded, whereas DBP formation in AOM-containing water decreased remarkably with halides added (freshwater > bromide loaded ≫ iodide loaded) at high UV fluence . Moreover, Pearson correlation analysis exhibited weaker correlation between DBPs and water parameters in AOM-containing water, while DBPs in HA-containing water exhibited better correlation with water parameters. For both simulated waters, the theoretical toxicity was calculated and peaked in bromide-containing water, whereas the calculated toxicity in iodide-containing water was comparable or slightly higher than that in freshwater. Therefore, UV/chlorine treatment may achieve good quality water with reduced DBP-associated toxicity in freshwater or iodide-containing water (iodide only), but careful consideration is needed when purifying source waters containing bromide (bromide only), especially for AOM/bromide-containing water.
研究领域:
环境科学
·
水处理工程
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Yu Li,Jie Li,Jia Ding,Zirong Song,Bochen Yang,Chuanming Zhang,Baohong Guan
The presence of nanoplastics in drinking water inducing inevitable exposure to human beings has aroused considerable attention. It is worth evaluating the degradation and even mineralization of nanoplastics in drinking water treatment plants designed for guaranteeing drinking water safety. Herein we mainly focus on the decomposition of nano-sized polystyrene plastics by two commonly used disinfection techniques, namely ozonation and chlorination. At recommended dosage for disinfection, ozonation achieves 99.9% molecular weight (MW) degradation and 42.7% mineralization of nano-sized polystyrene plastics in 240 min, while chlorination only attains 7.1% MW degradation and 4.3% mineralization. The overwhelming MW degradation is concentrated in first 30 min with 96.3% for ozonation and 4.2% for chlorination. With the proceeding of ozonation, the surface of nano-sized polystyrene plastics becomes rough and the particle size is decreased, during which the introduction of oxygen-containing groups on the surface of nano-sized polystyrene plastics increases the hydrophilicity of plastics, thus contributing to the further oxidative degradation to produce formic acid, phenol, acetophenone, hydroquinone and other products. However chlorination cannot roughen the surface of nano-sized polystyrene plastics, and only destroys a small amount of C-C bonds in main chain to form shorter chains polymers. This finding shows ozonation other than chlorination is available and effective for degradation of nano-sized polystyrene plastics, indicating that ozonation could be employed as a potential technique to tackle nanoplastics pollution in drinking water treatment plants.
研究领域:
环境科学
·
饮用水处理
✓ 已验证
DOI
高影响因子
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
·
2018
·
IF 2.891
Lulu Tong,Ying Qian
A naphthalimide-rhodamine fluorescent turn-on probe RHSNO with red emission for hypochlorous acid based on dual reaction linkage induce through-bond energy transfer (TBET) system was designed and synthesized. Rhodamine B thiohydrazide and naphthalimide -N,N- dimethylthiocarbamate (DMTC) were linked to form a structure of monothio-bishydrazide. In addition, introduce dimethylthiocarbamoyl chloride as another reaction site of ClO − , and it acts to quench the fluorescence of naphthalimide. In the presence of ClO − , RHSNO exhibits high selectivity toward ClO − at trace levels over other anions/ROS based on ClO − -triggered intramolecular desulfurization cyclization of rhodamine-thiohydrazide, the spiro ring of rhodamine was opened and meanwhile desulfurization hydrogenation happened at DMTC of naphthalimide moiety. These dual linkage reaction happened simultaneously made a typical TBET process took place from naphthalimide donor to rhodamine acceptor, an obvious increase of rhodamine emission at 590 nm and enhanced up to 260-fold gradually after adding ClO − with the increase of the concentrations. The efficiency of energy transfer was calculated to be 86%. And the quantum yield of rhodamine moiety is 0.64. Besides, the chemodosimeter RHSNO for ClO − with high sensitivity, a dramatic color change from colorless to brightly pink among 2 s after the addtion of ClO − . The detection limit was determined to be 22.1 nM and works excellently within a wide pH range of 5–10. Moreover, RHSNO had been employed for endogenous imaging in MCF-7 cell for ClO − . The results indicated that the probe could permeated into the cells and reacted with the intracellular ClO − . It is excellent to design fluorescence sensor RHSNO as a quick and effective method for detecting excess ClO − in living cell, for maintaining the balance of hypochlorite in the body and ensure normal life activities.
研究领域:
生物化学
·
医学检测
·
荧光分析
✓ 已验证
DOI
高影响因子
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
·
2020
·
IF 5.278
Linli Hou,Yonghai Song,Fengxiang Lang,Zhenrong Wang,Li Wang
A luminescent Tb 3+ -pyromellitic acid (H 4 L = pyromellitic acid) coordination polymer (Tb-H 4 L CP, TbL 0.5 (H 2 L) 0.5 (H 2 O)·DMF) was prepared for multiresponsive fluorescence sensor. The Tb-H 4 L CP exhibits uniform nanospheres with average diameter of 220 ± 20 nm, good crystalline structure, and good dispersion in water. The Tb-H 4 L CP emitted the characteristic green fluorescence through antenna effect from H 4 L which was an excellent antenna molecule when excited at 270 nm and could be used to selectively determine Fe 3+ and polychlorinated benzenes based on fluorescence quenching effect. The coordination between Fe 3+ and carboxylic oxygen of Tb-H 4 L to damage the antenna effect and polychlorinated benzenes absorb the excitation light to result the inner-filter effect of fluorescence, which quenched the fluorescence of Tb-H 4 L CP. The linear range for Fe 3+ was 2.0–100 μM with a detection limit of 0.7 μM and for 1,3,5-trichlorobenzene was 0–0.44 × 10 3 ppm with a detection limit of 0.087 ppm. The Tb-H 4 L CP demonstrates excellent fluorescence sensing performances, indicating that it can be used as a multi-response sensor to effectively measure toxic and harmful substances.
研究领域:
化学
·
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2017
·
IF 3.359
Junfeng Zhao,Yiqing Liu,Qun Wang,Yongsheng Fu,Xiaohui Lu,Xiaofeng Bai
In this study, the effect of phosphate, Fe(III), Fe(II), and reductive substances (i.e., Mn 2+ and SO 3 2− ) on diclofenac (DCF) oxidation and its degradation mechanism by Ferrate (Fe(VI)) were investigated. The removal rate of DCF in reaction solution at pH 9.0 adjusted by NaOH (67.36%) was higher than that by phosphate buffer (14.87%) because of the complexation of phosphate with Fe(III) and/or Fe(II) restraining the self-catalysis of Fe(VI). Fe(III) or Fe(II) could significantly catalyze Fe(VI) to generate more intermediates (i.e., Fe(V) and Fe(IV)), whose oxidation capacity was magnitude stronger than that of Fe(VI), leading to the improvement of DCF degradation, besides, the presence of reductive substances, e.g., Mn 2+ and SO 3 2− , could also increase the self-catalysis of Fe(VI), enhancing the removal of DCF, which will be further verified in follow-up studies. Seven oxidation products (OPs) were detected using a quadrupole-time of flight-mass spectrometer coupled with an ultra performance liquid chromatograph (LC-QTOF/MS). Based on these identified OPs, the potential degradation mechanism of DCF by Fe(VI) was proposed showing six reaction pathways, including hydroxylation, decarboxylation, C N bond cleavage, dehydrogenation, formylation, and dechlorination-hydroxylation. This study suggests that Fe(VI) can effectively oxidize and degrade DCF.
研究领域:
环境科学
·
化学
✓ 已验证
DOI
高影响因子
JOURNAL OF POLYMER SCIENCE
·
2022
·Vol. 60
·期 20
·2855-2865
·
IF 3.046
Muchen Lu,Yihu Song,Qiang Zheng,Wanjie Wang
Copper chloride (CuCl 2 ) is used in sulfur-cured natural rubber (NR) to regulate disulfide exchange reaction in self-healing process while factors influencing the healing capability remain unclear. Herein CuCl 2 and other additives including zinc oxide and sulfur are used to mediate self-healing efficiency of NR vulcanizates. For revealing the role of proteins and phospholipids in NR, the mediated self-healing capability is compared with sulfur-cured isoprene rubber (IR) vulcanizates. The results reveal that CuCl 2 interferes rheological responses and vulcanization dynamics in both rubbers, and it causes intermolecular disassociation in NR gums. As self-healing capability is closely related to crosslinking density, formulation is adjusted to balance healing efficiency and tensile strength. Healing efficiency of around 70% and the highest tensile strength of about 6 MPa are achieved at crosslinking density about 70 mol/m 3 when vulcanizates are healed at 140°C for 30 min. Graphical
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH PART B-PESTICIDES FOOD CONTAMINANTS AND AGRICULTURAL WASTES
·
2019
·
IF 1.463
Mingbo Ma,Suozhuai Dong,Wanhui Jin,Chongqi Zhang,Wenlong Zhou
Pesticides carried by cotton fiber are potential risk for production workers and consumers. Dissipation behaviour of a commonly used cotton pesticide profenofos in cotton fiber during growing period and scouring treatment was investigated. The results showed that profenofos in the fiber from the pre-opened and post-opened bolls both decreased to undetectable amounts 21 days after pesticide application. However, a minority of profenofos was converted to a strongly irritant compound, 4-bromo-2-chlorophenol and retained a non-negligible amount in cotton fiber even after 28 days. Profenofos and its degradation product could be completely removed during the conventional cotton scouring process. The degradation half-time of profenofos in scouring bath was only 3.0 min, and the degradation product was also 4-bromo-2-chlorophenol. Cotton products made of profenofos-carrying fiber are safe; however, the scouring waste should be detoxicated before discharge due to the accumulation of 4-bromo-2-chlorophenol in the scouring bath. These results could be useful for evaluating the risk of cotton fiber from the profenofos applied fields.
研究领域:
农业科学
·
环境科学
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）