INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2019
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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
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材料科学
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产品关联
DOI
PubMed
高影响因子
Environmental Chemistry Letters
·
2022
·Vol. 20
·期 4
·2243-2251
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IF 13.615
Zhu Guocheng,Chen Junming,Zhang Shanshan,Zhao Zilong,Luo Huihao,Hursthouse Andrew S.,Wan Peng,Fan Gongduan
Black-odorous waters are an increasingly common phenomenon characterized by excessive levels of nutrients, the formation of metal sufide precipitates, volatile sulfurous compounds, low dissolved oxygen and high chemical oxygen demand. Black-odorous waters frequently occur in lake and river systems where inputs have restricted circulation. The key remediation issue is the removal of nitrogen and phosphorus. Here, we present a novel aeration-adsorption system using fiber balls and we study treatment parameters and removal mechanism. Kinetics and changes of the solid phase were followed using Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction. Results show complete removal of ammonia N, initially at 31 mg/L, and 92.8% removal of total nitrogen, initially at 29 mg/L, after a 24 h reaction time at pH 9.67. At pH 5.67 and 9.67, total phosphorus and phosphate could be significantly reduced by 90–92% at 3.2–5.2 mg/L after 24 h. Treatment met China’s integrated wastewater discharge standards, demonstrating an effective and robust treatment capability. First-order and second-order kinetic models provided a good fit to the treatment data, indicating physical and chemical adsorption were involved in the treatment reactions. The reaction mechanism involved hydrogen substitution and binding to oxygen. These results present a cost effective and robust approach for the removal of N and P from black, odorous water, providing opportunity to abate environmental contamination.
研究领域:
环境工程
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水污染治理
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生态修复
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环境化学
✓ 已验证
DOI
高影响因子
WATER SCIENCE AND TECHNOLOGY
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2022
·Vol. 86
·期 5
·1017-1033
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IF 2.43
Fu Chengbin,Li Ye,Zuo Yangyang,Li Bolin,Liu Chang,Liu Dongxue,Fu Yan,Yin Yixin
It is essential to solve the problem of phosphorus pollution in urban landscape water and reduce the degree of eutrophication. In this paper, lanthanum-modified bentonite (La-B) was prepared by high-temperature calcination and liquid-phase precipitation. Then La-B was modified with chitosan to prepare a low-cost environment-friendly functional material: lanthanum/chitosan co-modified bentonite (La-BC). It can reach the adsorption equilibrium within 30 min, and the maximum adsorption capacity is 15.5 mg/g (initial phosphate concentration 50 mg/L); when the target concentration is 2 mg/L, the removal rate can reach 98.5%. La-BC has a stronger anti-interference ability to common coexisting anions SO 4 2− , HCO 3 − , NO 3 − and Cl − in the urban landscape water body. La-BC has excellent performance in weakly acidic to neutral water, and its pH applicable range has been improved, making it possible to apply in practical water. The fitting results show that the adsorption behavior conforms to the pseudo-second-order kinetic model and the Freundlich model. After 5 regenerations, the removal efficiency remained around 80%. In the actual water test results, the phosphate concentration can be controlled below 0.1 mg/L and the removal rate is above 75%. Due to its low cost and reusability, it has great potential in the practical application of phosphate removal from landscape water. La-BC high-efficiency phosphorus removal agent was prepared by high temperature calcination and liquid phase precipitation. La-BC has shown excellent competitiveness in actual landscape water application and regeneration experiments. A possible mechanism of La-BC adsorption of phosphate has been studied and analyzed.
研究领域:
环境科学
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材料科学
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水污染控制
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2024
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IF 12.2
Zuhao Chen,Yongyou Hu,Guanglei Qiu,Donghui Liang,Jianhua Cheng,Yuancai Chen,Xiaoqiang Zhu,Guobin Wang,Jieyun Xie
The effects of antibiotics, such as tetracycline, sulfamethoxazole, and ciprofloxacin, on functional microorganisms are of significant concern in wastewater treatment. This study observed that Acinetobacter indicus CZH-5 has a limited capacity to remove nitrogen and phosphorus using antibiotics (5 mg/L) as the sole carbon source. When sodium acetate was supplied (carbon/nitrogen ratio = 7), the average removal efficiencies of ammonia-N, total nitrogen, and orthophosphate-P increased to 52.46 %, 51.95 %, and 92.43 %, respectively. The average removal efficiencies of antibiotics were 84.85 % for tetracycline, 39.32 % for sulfamethoxazole, 18.85 % for ciprofloxacin, and 23.24 % for their mixtures. Increasing the carbon/nitrogen ratio to 20 further improved the average removal efficiencies to 72.61 % for total nitrogen and 97.62 % for orthophosphate-P (5 mg/L antibiotics). Additionally, the growth rate and pollutant removal by CZH-5 were unaffected by the presence of 0.1–1 mg/L antibiotics. Transcriptomic analysis revealed that the promoted translation of aceE , aarA , and gltA genes provided ATP and proton -motive forces. The nitrogen metabolism and polyphosphate genes were also affected. The expression of acetate kinase, dehydrogenase, flavin mononucleotide enzymes, and cytochrome P450 contributed to antibiotic degradation. Intermediate metabolites were investigated to determine the reaction pathways.
研究领域:
环境微生物学
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废水处理工程
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分子生物学
✓ 已验证
DOI
高影响因子
WATER RESEARCH
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2018
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IF 7.051
Zi-Bin Xu,Wen-Long Wang,Nan Huang,Qian-Yuan Wu,Min-Yong Lee,Hong-Ying Hu
2-Phosphonobutane-1,2,4-tricarboxylic acid (PBTCA) is an antiscalant that is widely used in reverse osmosis (RO) systems. Because of its high concentration in RO concentrate, eutrophication risk and anti-precipitation properties may affect subsequent treatments, therefore treatment strategies are needed to eliminate such substances. In this study, PBTCA was degraded by ozonation . The results show that PBTCA reacted with ozone molecules and hydroxyl radicals , with second-order rate constants of (0.12 ± 0.002) and (7.83 ± 1.51) × 10 8 L mol −1 s −1 , respectively. The phosphorus in PBTCA (P P ) was transformed into organic phosphorus except for PBTCA (P O ), and inorganic phosphorus (P I ); P O was further transformed into P I . The changes in the concentrations of these phosphorus forms were investigated by model simulation. Simulation showed that the rate of P P transformation into P O was 5.5 times higher than that into P I . PBTCA was ozonated much faster at alkaline pH than at acidic pH. This is ascribed to different amounts of ozone molecules and hydroxyl radicals, and their different reaction rates with PBTCA. Furthermore, anti-precipitation property was reduced during ozonation , as shown by the amounts and morphology changes of the precipitates. PBTCA concentration for 50% anti-precipitation (AP 50 ) did not change during ozonation, indicating that the transformation products generated during ozonation did not have anti-precipitation effects. Phosphorus in PBTCA was removed by ozonation–coagulation treatment. Total phosphorus and inorganic phosphorus were removed efficiently by using ferric chloride as a coagulant. The coagulants tended to bind with inorganic phosphorus to form flocs. Meanwhile, flocs were more easily to aggregate and precipitate as anti-precipitation effect was gradually removed, thus more phosphorus was removed. A combination of ozonation and coagulation removed PBTCA effectively and simultaneously reduced its anti-precipitation property and phosphorus.
研究领域:
环境科学
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水处理工程
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化学动力学
✓ 已验证
DOI
高影响因子
CARBOHYDRATE POLYMERS
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2021
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IF 9.381
Min Li,Xianlin Fan,Qian Mao,Qing Li,Xiujuan Zhang,Gaohong He,Shufen Zhang,Wenjun Zhang
Patients in hyperphosphatemia are orally prescribed with phosphate binders to excrete the non-metabolic phosphorus. Aiming for the bio-compatibility and binding efficacy, the Fe-based phosphate binders of low toxicity have been explored and improved. Herein, the hollow core-shell microcapsules as Fe@CH (nano ferric oxide entrapped in the polymerized chitosan) were constructed via emulsion interface polymerization, to enhance the phosphate binding from -NH 2 group and iron complex, and limit iron leakage significantly. Via the double emulsion polymerization based on the primary Pickering emulsion stabilized by oleic acid-modified ferric oxide, Fe@CH performed as the rough polymerized-chitosan microcapsules entrapping well-distributed ferric oxide for the phosphate adsorption in vitro . At pH 3 and pH 5, Fe@CH bound phosphorus efficiently, with the capacity of 55 mg/g and 65 mg/g respectively, along with the excellent shell isolation from iron leakage and remarkable safety. Prospectively, the Fe@CH micro-sorbent is the proper candidate as the phosphate binder for hyperphosphatemia.
研究领域:
材料科学
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医学
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生物工程
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2021
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IF 13.273
Xiaohui Liu,Jiamin Xu,Ying Liu,Xuan Zhang,Shaoyong Lu,Bin Zhao,Xiaochun Guo,Jian Zhang,Beidou Xi,Fengchang Wu
Pollution of sulfamethoxazole (SMX) in rural domestic sewage are a great challenge for ecological security because of limited treatment. In this study, an electrolysis-integrated bio-rack constructed wetland system (EC-CW-P) without substrates was developed for enhancing SMX removal in rural domestic sewage. The dynamic performance and mechanism of SMX (1 mg L -1 ) removal, occurrence of antibiotic resistance genes (ARGs) and microbial community composition at 4 ~ 24℃ were assessed. Meanwhile, the simultaneous removal performance of phosphorus in EC-CW-P was also analyzed due to key role of substrate adsorption and iron flocculation. The results revealed that the removal efficiency of SMX could reach 97.13% at 4 ~ 24℃ in the EC-CW-P by the electrocatalysis and adsorption of a ferric iron coagulant and biodegradation. Moreover, efficient removal of 74.12%~99.52% total phosphorus (TP) was obtained through electrocoagulation because of the formation of ferric ions. The occurrence of SMX had no effect on TP removal because of the different removal pathway. It should be emphasized that the removal efficiency of SMX owing to high microbial and plant activity which may be due to the formation of iron film and micro current stimulation and TP owing to adsorption of iron mud remained high (>80%) when the electrode was gradually passivated. Overall, the performance of bio-rack CW system was intensified by electrolysis (iron electrode) with higher bacterial abundance and plant activity in the EC-CW-P. However, the high relative abundance of sul ARGs (from 2.15 × 10 -1 to 2.41 × 10 1 copies 16S rRNA -1 ) in the influent of the EC-CW-P may pose a severe threat to ecosystem. These results provide a novel perspective for enhancing SMX and phosphorus removal by bio-rack constructed wetland system.
研究领域:
环境科学
·
微生物学
·
生态工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）