WATER RESEARCH
·
2018
·
IF 7.051
Chao Shan,Jiajia Chen,Zhe Yang,Huichao Jia,Xiaohong Guan,Weiming Zhang,Bingcai Pan
Although the removal of Se(VI) from water by using zero-valent iron (ZVI) is a promising method, passivation of ZVI severely inhibits its performance. To overcome such issue, we proposed an efficient technique to enhance Se(VI) removal via pre-corrosion of ZVI with H 2 O 2 /HCl in a short time (15 min). The resultant pcZVI suspension was weakly acidic (pH 4.56) and contained abundant aqueous Fe 2+ . 57 Fe Mössbauer spectroscopy showed that pcZVI mainly consisted of Fe 0 (66.2%), hydrated ferric oxide (26.3%), and Fe 3 O 4 (7.5%). Efficient removal of Se(VI) from sulfate-rich solution was achieved by pcZVI compared with ZVI (in the absence and presence of H 2 O 2 ) and acid-pretreated ZVI. Moreover, the efficient removal of Se(VI) by pcZVI sustained over a broad pH range (3–9) due to its strong buffering power. The presence of chloride, carbonate, nitrate, and common cations (Na + , K + , Ca 2+ , and Mg 2+ ) posed negligible influence on the removal of Se(VI) by pcZVI, while the inhibitory effect induced by sulfate, silicate, and phosphate indicated the significance of Se(VI) adsorption as a prerequisite step for its removal. The consumption of aqueous Fe 2+ was associated with Se(VI) removal, and X-ray absorption near edge structure revealed that the main pathway for Se(VI) removal by pcZVI was a stepwise reduction of Se(VI) to Se(IV) and then Se 0 as the dominant final state (78.2%). Moreover, higher electron selectivity of pcZVI was attributed to the enhanced enrichment of Se oxyanions prior to their reduction.
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2023
·Vol. 30
·期 28
·72966-72977
·
IF 5.8
Wang Zhongmiao,Yang Kun,Lin Daohui
Biochar releases colloidal particles into the environment during applications and aging which can become carriers of pollutants and influence on the environmental risk of pollutants due to the excellent adsorption and migration properties of biochar colloids (BCCs). The adsorption and desorption behaviors of BCCs can be different from their bulk ones due to the colloidal size, which merits specific studies. Herein, the adsorption and desorption of 2,4,4′-trichlorobiphenyl (PCB28) as a representative on BCCs released from bulk biochars prepared from bamboo chips at 300, 500, and 700 C and the effects of solution properties were specifically investigated. Results show that the adsorption was dominated by pore filling and π–π interaction, and thus, BCCs prepared at higher temperature with greater pore volume and aromaticity had higher adsorption of PCB28. Results show that the adsorption was dominated by pore filling and π–π interaction, and thus, BCCs prepared at higher temperature with greater pore volume and aromaticity had higher adsorption of PCB28. The saturation adsorption amounts of PCB28 on BCC300, BCC500, and BCC700 were 21.9, 40.3, and 62.4 mg/g, respectively. It is noteworthy that PCB28 possessed a significant desorption hysteresis from BCCs, with the hysteresis index (Ce = 80 μg/L) increased from 0.380 to 0.661 as the preparation temperature of BCCs rising from 300 to 700 ℃. High concentration of NaCl (100 mmol/L) was unfavorable for the adsorption and desorption. The presence of humic acid or fulvic acid (FA), especially the smaller FA, could inhibit the adsorption and desorption of PCB28 on BCCs due to micropore blocking. In seawater, groundwater, surface water, and soil solution samples, the PCB28 adsorption of BCCs was inhibited to varying degrees in comparison with that in deionized water, and the desorption was noticeably inhibited in the groundwater sample. These findings provide valuable information for the understanding of interactions between BCCs and organic contaminants in natural waters and for the environmental application of biochars as well. Graphical abstract
研究领域:
环境科学
·
污染生态学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2024
·
IF 5.3
Wei Du,Yiping Liu,Yifang Gao,Longjing Bai,Lei Zhang,Penggao Cheng,Na Tang
To further probe into the link between solution chemistry and nucleation processes experimental and computational data are presented on unsaturated, saturated, and supersaturated solutions and in situ monitoring of nucleation chemistry of p-chlorobenzoic acid (PCBA), p-methoxybenzoic acid (PMBA) and p-nitrobenzoic acid (PNBA), three benzoic acid derivatives with different properties of para-substituents. By variation of the gas media, we were able to establish that hydrogen-bonded dimers (HD) are the basic building unite in solution for clusters and nucleuses despite of the gases and solvents, and there is a strong link between the supersaturated solution chemistry and the intrinsic supersaturation ratio, and the nucleation kinetics. Two different molecular self-assembly pathways and the rate-controlling steps were discussed, which paves new aspects for understanding the role of solution chemistry in directing nucleation processes.
研究领域:
物理化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
RESEARCH ON CHEMICAL INTERMEDIATES
·
2016
·Vol. 43
·期 2
·1121-1138
·
IF 1.833
Ding Yao Yao,Cui Hao,Chen Jian
Dried powder of alligator weed root (AWR), a promising biosorbent, was employed to remove tetracycline (TC) from aqueous solution, using acid-pretreated AWR (HAWR) for comparison. The effects of ionic strength, pH, and environmentally coexisting substances on the adsorption of TC on AWR were also investigated. The results indicated a negligible impact of ionic strength but a significant effect of solution pH on the adsorption, with apparent inhibition observed in relatively acidic or alkaline pH regions. The impact of coexisting substances on TC adsorption depended on the species and concentration of interfering components. The mechanism of desorption was explored using NaCl/MgCl 2 solution and cyclohexane–methanol mixture, revealing intense TC adsorption on the AWR surface. The biosorbent was characterized using various techniques, including inductively coupled plasma (ICP), scanning electron microscopy (SEM) with energy-dispersive X-ray spectroscopy (EDS), Fourier-transform infrared (FTIR) spectroscopy, and zeta potential and N 2 adsorption/desorption analyses. The results of the ICP, SEM–EDS, and FTIR analyses indicated that metals including Mn, Fe, and Al were enriched mainly over the AWR surface with metal (hydr)oxide (MHO) morphology. When the MHOs were denuded by HCl solution pretreatment, the resulting HAWR totally lost the adsorption capability. Based on the nature of AWR and TC as well as the adsorption/desorption performance, MHOs over the AWR surface were verified to play an essential role in driving adsorption via surface complexation. Furthermore, MHO-based complexation provides a reliable explanation for the TC adsorption/desorption performance. The obtained results will aid adsorption mechanism elucidation and potential applications of such low-cost biosorbent.
研究领域:
环境科学
·
生物技术
✓ 已验证
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2013
·
IF 3.258
Fanfeng Zeng,Yan He,Zhenghua Lian,Jianming Xu
Hematite nanoparticles (NPs) were studied as a sorbent for hydrophobic organic contaminants (OCs) under natural ambient conditions through specially designed contrasting solution chemistry of electrolyte. Ionizable pentachlorophenol (PCP) and non-ionizable phenanthrene (PHE) were selected as representative OCs. The sorption capacities of PCP and PHE were pH-dependent, and a larger amount of PCP was sorbed at pH values below its pK a (4.75). However, the PHE sorption capacity was higher at relatively high or low pHs (e.g. below 4.0 and above 10.0), possibly due to the larger available surface area of the hematite NPs, caused by the higher values of net charges and charge density. Changes in pH might thus affect the sorption of OCs by hematite NPs, through modification of the surface characteristics of the sorbent and the electronic properties of the sorbate molecules. The influence of different ionic strengths indicated that the amounts of PCP and PHE sorbed by hematite NPs decreased as a concentration function of different types of ions (e.g. Na + , K + , Mg 2 + and Ca 2 + ), with the underlying mechanism possibly being due to four interactions i.e. hydrogen-bonding, competitive sorption by ions in the ambient solution, screening effects and aggregation effects. The results confirmed that the surface chemistry of hematite NPs, the chemical properties of PCP and PHE, and solution chemistry (e.g. pH and ionic strength) of the electrolyte all played an important role in PCP and PHE sorption by hematite NPs. By comparison of both sorption capacity and ecologic advantages, our results suggested that natural hematite NPs would be more competitive and efficient for PCP and PHE sorption than engineered NPs. This finding increases our knowledge regarding the environmental function of natural NPs (such as hematite NPs) for OC remediation through manipulating their interfacial behavior.
研究领域:
环境科学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL POLLUTION
·
2020
·
IF 6.793
Mengjie Wang,Yumeng Song,Haojing Zhang,Taotao Lu,Weifeng Chen,Wenwen Li,Wei Qi,Zhichong Qi
In this study, batch and column tests were performed to investigate the co-transport of graphene oxide (GO) nanoparticles and tetracycline in saturated porous media under various solution chemistry conditions. Research indicated that GO and tetracycline had mutual promotion effect on their transport in the porous media under all the tested conditions, which was ascribed to the high adsorption capacity of tetracycline onto GO and the increased electrostatic repulsion as well as their competition for deposition sites on sand surfaces. Interestingly, the mutually promoting function of GO and tetracycline under acidic conditions was greater than that under alkaline conditions, the dominant mechanism was that the increased solution pH decreased the sorption of tetracycline onto GO and weakened the deposition site competition. Furthermore, the mutually promoting effect of GO and tetracycline was Na + or Ca 2+ concentration-dependent. Specially, increased Ca 2+ concentration weakened the promoting effect of GO on tetracycline transport but magnified the promoting effect of tetracycline on GO transport. This is because higher Ca 2+ concentration could cause a decrease in the adsorption of tetracycline on GO and facilitate more tetracycline molecules to occupy the deposition sites on sand surfaces. Additionally, sodium dodecyl sulfate had enhancement effect on co-transport of GO and tetracycline. Findings from this study clearly indicated that antibiotics and carbon based nanomaterials may transport together under various solution chemistry conditions, and consequently affect their fates in aquatic environments.
研究领域:
环境科学
·
纳米材料科学
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2022
·Vol. 29
·期 60
·90248-90258
·
IF 5.19
Zhang Qian,Zhou Jinwen,Zhang Lishan,Zhong Shan,Ru Xuan,Shu Xiaohua
Pyrite affects the adsorption of tylosin (TYL) due to their coexistence in the lake system. As well as the reactivity groups of S–S-H, S-OH, and Fe-OH, defects also have the possibilities to influence the adsorption of organic contaminants. However, the role of these active sites in antibiotic adsorption on pyrite has not been deeply studied. Besides, pH, N, P, dissolved oxygen, and dissolved organic matter (DOM) fluctuate greatly in lake at different seasons, which may change the surface characteristics of pyrite. Hence, the adsorption of TYL on natural pyrite considered solution chemistry and DOM in lake water was explored in this study. The fitting results of the kinetic and isotherm models showed that the adsorption included physical and chemical interactions. The neutral initial solution pH was conductive to TYL adsorption owing to the combined result of electrostatic and cover of Fe-oxyhydroxide. NO 3 − and NH 4 + had no effect on TYL adsorption, whereas H 2 PO 4 − promoted adsorption by forming flocculent Fe(H 2 PO 4 ) 3 precipitates. The dissolved oxygen increased adsorption. This is due to the co-promotion of the pyrite oxidation by oxygen and sulfur defects. The Fe(II)-DOM complex caused by pyrite surface oxidation reduced the concentration of TYL in solution by gathering. Except for the surface charge, reactivity groups on pyrite significantly influenced the adsorption of TYL. The bond fracture of S–S resulted in sulfur defects that contributed to pyrite oxidation. As a result, Fe(III)/Fe(II) on the surface of pyrite or in solution produced a complex Fe(III)/Fe(II) with anions and DOM. In addition, Fe(III)-S on sulfur defects interacted with the O–H of TYL through hydrogen bonding. Furthermore, the Fe–O-C bond is formed by the interaction of C–OH on TYL and Fe(III) (hydr)oxides on the surface of pyrite. The study provides a deep insight into the effect of pyrite surface active sites on amphoteric antibiotic adsorption. It helps to understand antibiotic migration and interactions with widespread pyrite in the real environment. Graphical abstract
研究领域:
环境科学
·
水文学
✓ 已验证
DOI
高影响因子
WATER AIR AND SOIL POLLUTION
·
2020
·Vol. 231
·期 8
·1-15
·
IF 1.9
Ma Xiaohan,Xin Yanjun,Yan Qinghua,Pan Xiangrui,Xin Shuaishuai,Huang Xiaomin,Chen Qinghua,Liu Guocheng
Biochars from Chinese medicine material residues and furfural residues at 300–600 °C (MBC300–MBC600 and FBC300–FBC600) were used as adsorbents for removing tetracycline (TC) from water. The influence of pH and co-existing of cations or low molecular weight organic acids (LMWOAs) was investigated on TC adsorption. Further, the bulk biochars were treated by ball milling into sub-micron particles, and their properties and adsorption performance toward TC were also characterized. For pristine biochars, TC adsorption was nonlinear and heterogeneous. Heterogeneity of biochars resulted in multiple sorption mechanisms, including H-bonding, π-π interaction, and pore filling. FBC300 and FBC600 had maximum sorption at pH 5–7. Electrostatic repulsion of positively charged biochar surfaces with TCH 3 + at pH < 3 or negatively charged biochar surfaces with TCH − and/or TC 2− at pH > 7 was not favorable for TC removal. TC sorption decreased with increasing Na + concentrations from 0 to 0.1 mol/L, and bivalent cations (Ca 2+ and Mg 2+ ) showed greater inhibiting effect relative to monovalent ones (Na + and K + ). The LMWOAs could combine with co-existing cations, thus reducing the inhibitory effect of cations and improving TC sorption. The ball milling caused remarkable size reduction of biochar particles, thus exposing more active surfaces to capture more TC molecules from water. This study provided low-cost and high-efficiency biochar absorbents to remove antibiotics from water and will benefit for understanding the relationship between TC sorption characteristics/mechanisms and biochar properties.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 96
·93863-93866
·
IF 3.289
Xiang Zhou,Xiang Ke,Wei Jiang
Nanostructured energetic materials benefit from improved spatial distribution and enhanced interfacial contact between reducing agents and oxidizing agents, and thus they have attracted increasing attention in the past decade. In this study Al/CuO nanostructured energetic materials were prepared by combining a solution chemistry method and electrophoretic deposition. A piece of clean Cu foil was first placed in a solution consisting of NaOH and (NH4)S2O8 to form a layer of copper hydroxide, which was then dehydrated in an oven at 180 °C for 4 h to obtain CuO nanostructures. Nano Al particles were integrated with the CuO nanostructures by electrophoretic deposition to form Al/CuO nanostructured energetic materials. Thermal analysis showed that the prepared nanostructured energetic materials had lower apparent activation energy than that of a randomly mixed counterpart thanks to the structural design.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
POLYCYCLIC AROMATIC COMPOUNDS
·
2019
·
IF 1.237
Chunmiao Zhu,Yinhai Lang,Ben Liu,Huaxuan Zhao
Chitosan/reed biochar composite (CRBC) was synthesized and employed as an adsorbent to remove ofloxacin (OFL) from aqueous solution. The physical and chemical properties of CRBC were characterized by SEM, FTIR, and BET surface area. The initial OFL concentration, solution pH, and ion strength affecting the adsorption process were investigated. Batch adsorption experiments revealed that OFL adsorption amounts on CRBC increased with the increasing of initial OFL concentration. Furthermore, the solution pH and ion strength had significant effects on OFL adsorption. The adsorption was enhanced in neutral pH condition and was inhibited by the presence of NaCl. The adsorption kinetics was fitted by the pseudo-second-order model with higher correlation coefficients. The adsorption isotherms were better described by the Langmuir model, indicating monolayer adsorption process. The aim of current work was to develop a reed biochar and chitosan composite and explore the adsorption behavior of OFL.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
Materials Letters-X
·
2021
·
IF 0
Yan-Ming Chen,Jie Gao
Zinc oxide (ZnO) nanoparticles were synthesized by solution chemistry method with n-hexanol as solvent. The synthesized ZnO nanoparticles were characterized by Ultraviolet–visible spectroscopy, transmission electron microscope and X-ray powder diffraction, and the growth kinetics was studied by Lifshitz, Slyozov and Wagner model. The effects of temperature, the addition of deionized water and the concentration of zinc acetate dihydrate on the synthesis of ZnO nanoparticles were investigated. The results show that the nucleation and growth of ZnO nanoparticles were promoted by the addition of small amount of water, and the size of synthesized ZnO nanoparticles could be controlled by changing the amount of water addition and the concentration of zinc acetate dihydrate.
研究领域:
材料科学
·
纳米技术
✓ 已验证
产品关联
DOI
DALTON TRANSACTIONS
·
2020
·Vol. 49
·期 18
·5957-5964
·
IF 4.174
Weiming Liu,Caiyun Liu,Wenli Wu,Guanyun Zhang,Jian Zhang,Chen-Ho Tung,Yifeng Wang
For the preparation of aqueous Ti-oxo clusters (TOCs) without organic ligands, organic ammonium cations (OACs) are important, but the mechanism is obscure. Here, the Ti4+/SO42− system was chosen as a model to investigate the roles of OACs. Three {Ti4} clusters were isolated from this system with different cationic additives. Structural analysis revealed a structural role of OACs: the hierarchically ordered array of the OACs in the organic layers was responsible for the stability and formation of crystalline precipitates. 17O NMR spectroscopy was used to study the interactions of OACs and SO42− with the Ti-oxo species in water under highly acidic conditions. SO42− enhanced the condensation of Ti4+ by binding to the TOC species. OACs could not enhance the condensation of Ti4+ but could change the solution speciation and especially promote the formation of {Ti18O27} clusters. We speculate that OACs interact with the cationic/neutral TOCs through anionic bridges to change the speciation. Under the synthetic conditions of {Ti4}, {Ti18O27} is the native TOC in solutions but {Ti4} is not.
研究领域:
无机化学
·
材料科学
·
分析化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）