CHEMICAL ENGINEERING JOURNAL
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2024
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IF 13.3
Yunfeng Xu,Xiaoxun Huang,Chuyin Liu,Dongning Kong,Guangren Qian
Arsenic (As) contamination of soils adversely affects human health and ecosystems and is an environmental issue of serious concern worldwide. Efficient and economical remediation methods are urgently needed. In this research, a chitosan-modified scrap iron filings (CFF) composite was prepared by using industrial scrap iron filings and chitosan to stabilize As-contaminated soil. The optimal modification conditions were explored, and CFF was applied to As-contaminated soil to investigate its remediation effect and stabilization mechanism. The results showed that the optimal preparation conditions of CFF were chitosan concentration of 3.75 % (w/w), chitosan to scrap iron filings ratio of 1:1, optimal modification temperature of 40 °C, iron filings particle size of 35–80 mesh, and 10 % glutaraldehyde crosslinking for 6 h, and the stabilization efficiency of As was 73.98 %. The adsorption behavior of CFF was consistent with the pseudo-second-order kinetic model and the Langmuir isotherm model, and the best adsorption effect was achieved at pH = 5–6. The possible mechanisms of As stabilization by CFF were surface complexation, hydrogen bonding synergy, precipitation, electrostatic attraction, and van der Waals forces.
研究领域:
环境科学
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土壤修复
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产品关联
DOI
高影响因子
Journal of Cleaner Production
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2019
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IF 6.395
Xufang Li,Weiyu Chen,Luming Ma,Yuanxing Huang,Hongwu Wang
Iron shavings were modified and used as the catalyst (named as Fe-shaving-based catalyst) for the ozonation of bio-treated coking wastewater. The difference of organic pollutants oxidation between catalytic and sole ozonation processes was characterized by MW (Molecular Weight) distribution and 3DEEM (Three-dimensional Excitation and Emission Matrix Fluorescence) analysis. Removals of the pollutants with MW of 5–10 kDa and 10–20 kDa in catalytic ozonation process were 81.5% and 85.2%, which were far better than that in sole ozonation process (31.1% and 41.8%). Organics with MW of 0.3–2 kDa and 2–5 kDa would accumulate in both two processes, while the accumulation amount in catalytic ozonation process was half of it in sole ozonation process. The removal of fluorescent substances in catalytic ozonation process experienced a procedure of lower firstly (<15 min) and then higher (>15 min) than that in sole ozonation process. The slight residual fluorescent substances were completely removed in catalytic ozonation process, while remained unchanged in sole ozonation process with the reaction time increasing to 180 min. The catalytic effect of Fe-shaving-based catalyst was better than commonly used powder catalysts and the TOC (Total Organic Carbon) removal attained to 78%. Hydroxyl radicals (·OH) were confirmed to be the effective oxidant in catalytic ozonation process through inhibition experiments. The cumulative ·OH formations with 200 g/L Fe-shaving-based catalyst during 180 min were 362 μmol, which explained the better catalytic effect of it. The surface hydroxyl groups were determined to be the most probable active sites for ·OH generation through phosphate inhibition experiments. Besides the excellent catalytic effect, using Fe-shaving-based catalyst provided a feasible resource utilization method of industrial waste Fe-shavings. Thereby, it is a promising catalyst for practical industrial wastewater advanced treatment with catalytic ozonation process.
研究领域:
环境科学
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废水处理
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产品关联
DOI
高影响因子
BIORESOURCE TECHNOLOGY
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2024
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IF 9.7
Yu Feng,Xingyu Zhang,Caiwei Zhang,Haozhe Xu,Xiaoming Ji,Jianfang Wang,Peng Wu,Feiyue Qian,Chongjun Chen,Yaoliang Shen,Wenru Liu
In this study, waste iron scraps (WIS) were exerted to alleviate sulfide inhibition on anammox bacteria and promote anammox nitrogen removal from sulfide-containing wastewater. Short-term batch experiments showed that WIS-addition led to the anammox bacteria activity increasing by 124.8 % at an initial sulfide concentration of 40 mgS/L. During the long-term experiments, the nitrogen removal rate (NRR) reached to 8.76 kg/(m 3 ·d) in the WIS-added reactor, while the maximum NRR was only 3.77 ± 0.31 kg/(m 3 ·d) in the non-WIS reactor. In contrast to anammox bacteria development in the non-WIS reactor, the relative abundance of Candidatus Kuenenia (1.4–3.7 %) declined significantly in the WIS-added reactor, but novel potential anammox bacteria Brocadiaceae_unclassified (60.1 %-78.6 %) were highly enriched. Overall, the experimental evidence suggested that WIS-addition not only mitigated the sulfide inhibition on anammox bacteria, but also promoted novel anammox bacteria proliferation. The findings of this work provide a promising solution for wide engineering applications of anammox treating sulfide-containing wastewater.
研究领域:
环境工程
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微生物学
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DOI
PubMed
高影响因子
WATER RESEARCH
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2016
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IF 5.991
Jin Wu,Luming Ma,Yunlu Chen,Yunqin Cheng,Yan Liu,Xiaosong Zha
Catalytic ozonation of organic pollutants from actual bio-treated dyeing and finishing wastewater (BDFW) with iron shavings was investigated. Catalytic ozonation effectively removed organic pollutants at initial pH values of 7.18–7.52, and the chemical oxygen demand (COD) level decreased from 142 to 70 mg·L −1 with a discharge limitation of 80 mg·L −1 . A total of 100% and 42% of the proteins and polysaccharides , respectively, were removed with a decrease in their contribution to the soluble COD from 76% to 41%. Among the 218 organic species detected by liquid chromatography-mass spectrometry, 58, 77, 79 and 4 species were completely removed, partially removed, increased and newly generated, respectively. Species including textile auxiliaries and dye intermediates were detected by gas chromatography-mass spectrometry. The inhibitory effect decreased from 51% to 33%, suggesting a reduction in the acute toxicity. The enhanced effect was due to hydroxyl radical ( OH) oxidation, co-precipitation and oxidation by other oxidants. The proteins were removed by OH oxidation (6%), by direct ozonation, co-precipitation and oxidation by other oxidants (94%). The corresponding values for polysaccharides were 21% and 21%, respectively. In addition, the iron shavings behaved well in successive runs. These results indicated that the process was favorable for engineering applications for removal of organic pollutants from BDFW.
研究领域:
环境科学
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水处理
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催化
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废水管理
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）