REACTIVE & FUNCTIONAL POLYMERS
·
2014
·
IF 2.822
Fu Liu,Bi-rong Ma,Dong Zhou,Li-Jing Zhu,Yin-Yi Fu,Li-xin Xue
A novel positively charged loose nanofiltration (NF) membrane was fabricated feasibly by UV-induced photografting polymerization of diallyl dimethyl ammonium chloride (DADMAC) on Polysulfone ultrafiltration membrane. A possible reaction mechanism was proposed that a linear chain structure and/or pyrrole like five-membered nitrogen heterocycles structure on the side chain were grafted to form the active barrier layer. NF membrane demonstrated a looser average pore size of 8.6 nm and positive charges surface. Owing to the nanoscale ultrathin nanoscale barrier layer and the combination of Donnan exclusion and steric hindrance , NF membrane exhibited good hydrophilicity , a high pure flux of 60 L/m 2 h (0.5 MPa), a good salt rejection to Mg 2+ (90.8%), Al 3+ (94.0%), Ca 2+ (91.5%), and a high dye rejection to methylene blue (99.4%) and congo red (100.0%) respectively. The salts rejection of NF membrane to different salts followed the order of AlCl 3 > CaCl 2 > MgCl 2 > NaCl > LiCl > MgSO 4 > Na 2 SO 4. NF membrane showed certain fouling resistance to seawater and BSA solution. The grafting polymerization kinetics were comprehensively investigated including irradiation time, monomer concentration and irradiation intensity. X-ray Photoelectron Spectroscopy (XPS), scanning electron microscopy (SEM), atomic force microscopy (AFM) and contact angle measurement were employed to investigate membrane chemistry, morphologies, and hydrophilicity.
研究领域:
材料科学
·
环境工程
·
膜分离技术
·
高分子化学
·
水处理
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2019
·
IF 4.784
Huayong Luo,Xueyang Zeng,Peng Liao,Hongwei Rong,Tian C. Zhang,Z. Jason Zhang,Xiangchao Meng
Currently, there is a growing trend in employing natural biomaterials (e.g., alginate) to prepare a novel bead adsorbent for phosphorus (P) elimination. However, the utilization of alginate beads to remove and recover P from effluents possesses limitations associated with its physical characteristics such as a dense gel layer, poor mechanical strength and low stability. To overcome the limitations and improve the adsorption performances, we synthesized a novel alginate-derived bead constituted of PNIPAM network interpenetrated in alginate-Zr 4+ network (PNIPAM/SA-Zr) decorated with polyethylene glycol as a pore-forming agent, and then investigated its ability to remove and recover P from effluents. The morphology, functional groups, surface area, and mechanical strength of the beads were evaluated by SEM, FTIR , BET, and swelling analysis. The adsorption of P was investigated by varying various factors. The adsorption kinetics , isotherms, and thermodynamics were studied. Particularly, the P-loaded beads exhibited a faster desorption rate under thermal stimulus, and remained good desorption efficiency and reusability within five consecutive cycles. Zeta-potential and XPS results revealed that the adsorption mechanisms were related to electrostatic interactions, ligand exchange, and the formation of inner-sphere complexes. The beads possessed favorable fixed-bed column operation performances for P removal and recovery from real wastewater.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Desalination and Water Treatment
·
2024
·Vol. 57
·期 59
·28947-28956
·
IF 1
Qiao Wang,Guang-shan Zhang,Han Chen,Peng Wang
A specially designed combined process of pre-oxidation and nanofiltration membrane was utilized to remove As(III) in the contaminated water without reagent addition and sediment creation in this work. Different parameters that affected the rejections of As(III) and As(V) were discussed, including the initial concentration, pH of the feed, and the cross-flow filtration pressure. The rejection of As(III) was over 70% which was restricted to the high initial feed concentration, while it was around 40% under the other conditions. Whereas, the rejection of As(V) maintained above 95% in all tests. As a result, As(III) was first pre-oxidized before membrane filtration. The ozone and aeration oxidation methods were used to oxidize As(III). The effects of aeration time and oxidation time were studied. The experimental results indicated that the rejection of As(III) was increased to over 90% after pre-oxidation, and the permeate could meet the drinking water standard for As in China. Particularly, the aeration took a much longer oxidation time than ozone, but it was still a more suitable method as the pre-oxidation process because of its safety and easy operability.
研究领域:
环境工程
·
水处理技术
·
膜分离
·
污染物控制
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL GEOCHEMISTRY AND HEALTH
·
2019
·Vol. 41
·期 3
·1545-1557
·
IF 3.252
Ye Bin,Cang Yan,Li Ji,Zhang Xiaolei
Chlorine dioxide (ClO 2 ) has been widely used in the process of preoxidation and disinfection as an excellent water treatment reagent. However, the inorganic by-products produced by ClO 2 , such as chlorite (ClO 2 − ) and chlorate (ClO 3 − ) are harmful to human health, and this has become a potential problem when using ClO 2 in drinking water treatment. In this study, ClO 2 alone and a ClO 2 /NaClO combination process were carried out to evaluate the algae removal efficiency of the treatment and the formation of disinfection by-products (DBPs: chlorite, chlorate, trihalomethanes and haloacetic acids) for high algae-laden water with 124.16 µg L −1 chlorophyll a (Chl.a) content. The results show that disinfection with 1.5 mg L −1 ClO 2 alone results in a ClO 2 − concentration exceeding 0.7 mg L −1 . ClO 2 preoxidation/ClO 2 disinfection is applicable for the control of effluent quality, but the ClO 2 − concentration still has an excessive risk when using 0.8 mg L −1 and 0.6 mg L −1 ClO 2 for the two process, respectively. In the ClO 2 /NaClO combination process, the ClO 2 − concentration is below 0.6 mg L −1 , and trihalomethane (THM) and haloacetic acid (HAA) concentrations are lower than 60% of the maximum contaminant levels (MCLs) set by the World Health Organization (WHO). Further, the formation of ClO 2 − is more effectively controlled by NaClO preoxidation/ClO 2 disinfection than ClO 2 preoxidation/NaClO disinfection.
研究领域:
环境科学
·
水处理工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
PRECISION ENGINEERING-JOURNAL OF THE INTERNATIONAL SOCIETIES FOR PRECISION ENGINEERING AND NANOTECHNOLOGY
·
2016
·
IF 1.914
Kun Shan,Ping Zhou,Yunsheng Zuo,Renke Kang,Dongming Guo
Electrogenerated chemical polishing (EGCP) had been proved effective in improving both the smoothness and the flatness of copper surface in our previous work. In this paper the polishing ability, defined as the ratio between the material removal rate at the peak and at the valley of a rough surface, is studied theoretically and experimentally. In a mathematical model, the effects of the special wavelength L , the peak-to-valley height h of the workpiece surface profile and the working distance d between working electrode and workpiece surface on the polishing ability are studied. The results show that the polishing ability decreases with increasing the working distance and finally approaches the value ( d + h )/ d , if L is much larger than d . However, the effect of the working distance on polishing ability is negligible, if L is close to or less than d . The polishing ability also decreases with h decreasing. Based on the above analysis, an analytical expression of the polishing ability of EGCP is given. For validating the theoretical analysis, a copper surface is polished by EGCP and the change of the surface profile is measured and analyzed using the analytical expression. The measured polishing ability agrees well with the simulation results.
研究领域:
材料科学
·
表面工程
·
电化学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Hongyuan Xi,Song Zhou,Jinxi Zhou
NO is the main precursor of photochemical smog. Since the SCR system of marine diesel engines has many disadvantages, this paper proposes an effective wet method to remove NO from the exhaust gases of marine diesel engines. Experiments were performed in a bubble column reactor to study the absorption of NO using sodium persulfate (Na 2 S 2 O 8 )/urea ((NH 2 ) 2 CO) solutions from a simulated gas stream. The effects of various operating parameters on NO removal were investigated, including reaction temperature, urea concentration, Na 2 S 2 O 8 concentration and the initial pH value of Na 2 S 2 O 8 /urea solutions. The experimental results showed that the NO removal efficiency increased with increasing reaction temperature (25–80 °C) and increasing Na 2 S 2 O 8 concentration (0.01–0.2 mol/L). When the concentration of urea was higher than 0.5 mol/L at 60 °C, 1 mol/L at 70 °C or 2 mol/L at 80 °C, the NO removal efficiency increased with the increase of urea concentration (0.1–4 mol/L). The highest NO removal efficiency was 99.7%, occurring at 80 °C when the concentrations of Na 2 S 2 O 8 and urea were 0.1 mol/L and 4 mol/L, respectively, and the concentration of nitrate was 14.93 mg/L. The optimal urea conditions were well below the legal limit of 60 mg/L. The NO removal efficiency increased with the increase of initial pH value within the herein investigated range of 7–9. All the experimental data showed that the novel system not only achieved effective NO removal efficiency, but also reduced the nitrate in wastewater, which could thus be applied to denitrification of marine engine exhaust gases.
研究领域:
环境工程
·
大气污染控制
·
化学工程
·
海洋工程
·
能源与动力工程
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2015
·Vol. 132
·期 17
·
IF 1.768
Ronglan Wu,Lingyuan Tian,Wei Wang,Xiaolin Man
In this article, we report a study of the design and synthesis of a bifunctional cellulose derivative on the removal of phenols and heavy-metal ions in wastewater treatment. A radical polymerization was performed in an ionic liquid, 1-allyl-3-methylimidazolium chloride, to graft two monomers, butyl methacrylate and 4-vinyl pyridine, on the backbone of cellulose. The effects of the five reaction conditions on the yield of final products were evaluated. The grafted celluloses were characterized by means of Fourier transform infrared spectroscopy, scanning electron microscopy, and thermogravimetric analysis. Adsorption experiments were carried out on the cellulose- g -poly(butyl methacrylate- co -4-vinyl pyridine) to evaluate the capacity of the removal of 2,4-dichlorophenol (2,4-DCP) and Cu(II) in water. The adsorption isotherms were measured at five temperatures and interpreted by a Langmuir model of adsorption. The thermodynamics of the adsorption suggested that the binding process was mildly exothermic for Cu(II) and endothermic for 2,4-DCP. Kinetic studies were interpreted with a pseudo-second-order adsorption model. The process of the adsorption of 2,4-DCP could be described overall by the model, whereas the adsorption of Cu(II) involved two processes. This was due to adsorption both on the surface and inside the adsorbent. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132 , 41830.
研究领域:
环境化学
·
高分子材料科学
·
水处理技术
·
吸附分离
·
绿色化学
✓ 已验证
DOI
高影响因子
Desalination and Water Treatment
·
2024
·
IF 1
Xin Wen,Zhanfang Cao,Jing Wang,Shuai Wang,Hong Zhong
A novel tri-isopropanolamine functionalized graphene oxide (TI-GO) adsorbent was synthesized by one-step reaction at 358K. Then the prepared TI-GO was characterized by SEM-EDS, FTIR, Raman spectra, TG, BET and XPS. The characterization results indicated the TI-GO has been synthesized successfully and it interact with Pb(II) ions through its nitrogen and oxygen-containing functional groups. Batch adsorption experiments were applied to evaluate the optimized conditions of adsorption. The results indicated that the TI-GO can reach equilibrium adsorption in 30 min and get maximum adsorption capacity at 293 K, pH 5.0. Besides, the adsorption kinetic and adsorption isotherm research indicated that the adsorption of TI-GO fit pseudo-second-order (PSO) kinetic and Langmuir adsorption isotherm model. In addition, the maximum adsorption capacity evaluated by Langmuir adsorption isotherm equation is 1478 mg/g.
研究领域:
环境科学
·
材料科学
·
化学工程
·
环境污染治理
·
吸附材料
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2017
·
IF 6.065
Li Fang,Liang Li,Zan Qu,Haomiao Xu,Jianfang Xu,Naiqiang Yan
A novel method was developed and applied for the treatment of simulated wastewater containing multiple heavy metals. A sorbent of ZnS nanocrystals (NCs) was synthesized and showed extraordinary performance for the removal of Hg 2+ , Cu 2+ , Pb 2+ and Cd 2+ . The removal efficiencies of Hg 2+ , Cu 2+ , Pb 2+ and Cd 2+ were 99.9%, 99.9%, 90.8% and 66.3%, respectively. Meanwhile, it was determined that solubility product ( K sp ) of heavy metal sulfides was closely related to adsorption selectivity of various heavy metals on the sorbent. The removal efficiency of Hg 2+ was higher than that of Cd 2+ , while the K sp of HgS was lower than that of CdS. It indicated that preferential adsorption of heavy metals occurred when the K sp of the heavy metal sulfide was lower. In addition, the differences in the K sp of heavy metal sulfides allowed for the exchange of heavy metals, indicating the potential application for the sequential removal and separation of heavy metals from wastewater. According to the cumulative adsorption experimental results, multiple heavy metals were sequentially adsorbed and separated from the simulated wastewater in the order of the K sp of their sulfides. This method holds the promise of sequentially removing and separating multiple heavy metals from wastewater.
研究领域:
环境科学
·
环境工程
·
纳米材料
·
水污染控制
·
化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF THE ENERGY INSTITUTE
·
2021
·
IF 6.186
Dongjing Liu,Lingtao Yang,Bin Li,Jiang Wu
Rice husk , as an abundant agricultural waste and renewable biomass, is adopted to produce porous silica which is used as a potential carbon-free adsorbent for mercury emission control of coal-fired power plants. The rice husk derived porous silica (RHS) exhibits a good Hg 0 adsorption capability with Hg 0 removal efficiency above 80% in the temperature range of 60–140 °C, which is plausibly due to the big specific surface area and mesoporous structure. The mercury removal performance of RHS can be evidently reinforced by KBr modification. The optimal KBr loading value and reaction temperature are 2 wt% and 140 °C, respectively. Acidic gas components, such as NO and SO 2 , both show slight inhibitive effects on Hg 0 adsorption process probably owing to the competitive adsorption or the elimination of adsorption sites.
研究领域:
环境科学
·
大气污染控制
·
材料科学
·
吸附技术
·
能源工程
✓ 已验证
DOI
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
·
2022
·
IF 4.598
Dexi Liu,Shichang Xu,Yanmeng Cai,Yue Wang,Jiaqi Guo,Youlin Li
The conventional separation technologies, like chemical precipitation and adsorption processes, cannot quickly and selectively separate and recycle heavy metal ions from waste. Due to its rich sulfur content and excellent electrical conductivity, vanadium disulfide is a potential material for effectively removing lead from wastewater. The vanadium disulfide material with selective adsorption ability was introduced into CDI technology to construct a coupling technology with both advantages. The N -doped modified ZIF@vanadium disulfide (ZAC@VS 2 ) composites were successfully synthesized by hydrothermal method. Electrosorption experiments show that ZAC@VS 2 material presents the remarkable saturated adsorption capacity to lead(II) ions (239.52 mg/g) in the 500 mg/L PbCl 2 solution. In the triplex blend system (Fe 3+ /Pb 2+ /Na + ) with each solute density of 100 mg/L, the saturated adsorption efficiency of 85.4% to Pb 2+ can still be maintained. In addition, compared with the Langmuir(R 2 =0.873) adsorption isotherm model, the Freundlich model (R 2 =0.922) can be better used to fit the adsorption process, which proves that the adsorption process is multilayered and heterogeneous. XPS tests and competitive adsorption experiments show that the electric double layer (EDL) and complexation together promote the selective adsorption of heavy metal ions by ZAC@VS 2 . ZAC@VS 2 composite electrode shows excellent performance in the removal of lead ions in battery waste liquid, indicating the potential of introducing ZAC@VS 2 into CDI to remove lead ions.
研究领域:
环境科学
·
材料科学
·
水处理技术
·
重金属污染控制
·
电化学工程
✓ 已验证
DOI
高影响因子
DESALINATION
·
2019
·
IF 6.035
Yuchen Wu,Mingfu Gao,Weitao Chen,Zhenhua Lü,Sanchuan Yu,Meihong Liu,Congjie Gao
In this work, nanofiltration membrane with an asymmetric selective separation layer and improved surface negative charge was designed and fabricated to efficient remove anionic dyes from aqueous solution. Firstly, loose polyester selective separation layer was formed through interfacial polymerization of triethanolamine and trimesoyl chloride. Surface carboxylation was then implemented via esterification using poly(acrylic acid) to generate a dense skin. Membrane characterizations verified the asymmetric structure and enrichment of surface carboxyl group, which endowed the carboxylated membrane with improved perm-selectivity and anti-dye-deposition property to anionic dye aqueous solutions. The desired surface carboxylated membrane exhibited 99.6% methyl blue removal, 8.05 l/m 2 h bar steady-state water permeability and 14.3% relative flux decline ratio under 5.0 bar. The water permeability of carboxylated membrane to methyl blue aqueous solution was higher than those of most reported membranes and even at least two times higher than that of the polyester-based membrane having nearly the same dye removal ability. The attractive results indicate that surface carboxylated polyester based thin-film composite membrane is a promising material for high-efficiency nanofiltration of anionic dye aqueous solution. This study provides valuable insights into the construction and fabrication of high performance nanofiltration membrane for efficient treatment of anionic dye aqueous solution.
研究领域:
环境工程
·
膜科学与技术
·
水处理
·
材料化学
·
纳米技术
·
分离科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）