FUEL PROCESSING TECHNOLOGY
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2020
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IF 4.982
Hongyuan Xi,Song Zhou,Zhao Zhang
A novel method based on a Na 2 S 2 O 8 /urea composite system was used to both synchronously absorb SO 2 and NO from marine diesel engine emissions and reduce the nitrate residues in cleaning wastewater. In the Na 2 S 2 O 8 /urea solution, a temperature of over 60 °C and a Na 2 S 2 O 8 concentration of >0.05 mol/L were found to fully absorb SO 2 by overcoming the SO 2 release and effectively absorb NO. Urea successfully reduced the residual nitrate concentration and improves NO absorption at a concentration below 2 mol/L. The NO and SO 2 removal efficiencies reached 97.8 ± 1.5% and 100%, respectively, at 70 °C in 0.1 mol/L Na 2 S 2 O 8 and 1.5 mol/L urea solutions. The residual nitrate concentration was 8.12 ± 0.25 mg/L, far below the regulatory limit of 60 mg/L. Acidic conditions (pH ≤ 5.5) could be conducive to absorbing NO and reducing the residual nitrate concentration. Based on the experimental results, this novel method is highly promising for reducing ship emissions.
研究领域:
环境科学
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化学工程
✓ 已验证
DOI
高影响因子
Journal of Chemistry
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2019
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IF 1.727
Han Zhitao,Gao Yu,Yang Shaolong,Dong Jingming,Pan Xinxiang,Lan Tian,Song Liguo,Yan Zhijun,Sun Deping,Ning Kaixuan
Experiments were conducted to remove NO from simulated flue gas in a rotating packed bed (RPB) reactor with NaClO2 as wet scrubbing oxidant and diesel exhaust gas as carrier gas. The effects of various operating parameters (rotational speed, solution pH, NaClO2 concentration, liquid-gas ratio, and NO and SO2 concentrations) on NO removal performance were investigated preliminarily. The results showed that with the increase of rotational speed, oxidant concentration, and liquid-gas ratio, NO removal efficiency increased obviously. NO removal efficiency increased largely with the decrease of solution pH, and a complete removal of NO could be attained at pH 4. NO concentration imposed little effect on NO removal efficiency while coexisting SO2 in exhaust gas could enhance NOx removal greatly.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
CATALYSIS TODAY
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2019
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IF 4.888
Yuhan Ma,Huawang Zhao,Cuijuan Zhang,Yingnan Zhao,Hong Chen,Yongdan Li
Cu-SSZ-13 is a highly active catalyst to remove NO x in the emission of diesel-powered engine. However, the enhancement of its stability in high-temperature (HT) hydrothermal conditions is a well-known challenge in application. This work presents a simple strategy to significantly improve its hydrothermal stability under HT hydrothermal condition by mechanically mixing another CHA type zeolite, Cu-SAPO-34. Both the two zeolites are synthesized via one-pot method, mixed in different ratios, and treated in 10% H 2 O/air at 750 °C for 16 h. The mixed samples are characterized before and after the hydrothermal treatment, and tested in NH 3 -SCR from 150 to 550 °C. The results show the activity of the hydrothermally treated catalysts increases with the increase of the amount of Cu-SAPO-34 up to 50 wt% in the mixed sample. The hydrothermal stability of Cu-SSZ-13 is obviously enhanced by mixing with Cu-SAPO-34. The dealumination is suppressed during the hydrothermal treatment; the framework and the isolated Cu 2+ sites are largely maintained in Cu-SSZ-13. This is attributed to the interaction between the two CHA zeolites during the hydrothermal treatment. We propose the delivery of extra-framework P species from Cu-SAPO-34 to Cu-SSZ-13 is critical to enhance the HT hydrothermal stability.
研究领域:
环境科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
Molecular Catalysis
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2022
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IF 5.089
Yi Yang,Jia Fang,Zhongwei Meng,Ping Pu,Qian Zhang,Chengcheng Yi,Suozhu Pan,Yalong Li
To solve the soot elimination and optimize catalyst diesel particulate filter (CDPF) regeneration strategies, a series of Mn-Ce catalysts with different Mn/(Mn+Ce) molar ratios are successfully synthetized by hydrothermal method and the complete catalytic oxidation of diesel engine soot are investigated. Compare to CeO 2 and MnO 2 , the catalytic promotion on soot combustion of Mn-Ce catalysts is more excellent by thermogravimetric experiments due to their better ability to activate oxygen species, which is consistent with results in characterization analysis. Among as-prepared catalysts, MC-0.40 has the best catalytic activity with the lowest starting temperature ( T s ), peak temperature ( T p ) and largest comprehensive combustion index ( S ) both in O 2 /N 2 and NO/O 2 /N 2 atmosphere. Influence factors on catalytic performance are studied. Weight ratios of soot/MC-0.40 catalyst are suitable at the range of 1:9–1:13, which makes soot combustion more easily. Ashes in the reaction process show adverse effects due to their ability to increase ignition point by inhibit heat and oxygen transfer. Mn-Ce catalysts are more sensitive and show better catalytic activity in NO atmosphere because of generations of abundant adsorbed species and NO adsorption/desorption. The three consecutive cycles of MC-0.40 catalyst are performed to study the catalytic stability, and thermogravimetric curves show that the potential reusability of MC-0.40 catalyst can be relatively accepted in soot combustion.
研究领域:
环境科学
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催化材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2024
·
IF 12.2
Jiao Li,Haorang Song,Linfeng Zhang,Jie Li,Yanlin Yang,Xiangfen Cui,Anjum Mahfuza,Yan Cao,Xuewei Hu,Chen Li,Qun Zhao,Senlin Tian
Air pollution is one of the major environmental risks threatening human health, diesel exhaust particulate matter (DEPM) is an important source of urban air pollution, and oral ingestion is the primary route of exposure to atmospheric particulate matter. This study examined the bioaccessibility of Cr, Fe, and Zn in DEPM within simulated saliva fluids through in vitro experiments, interactions between the particles and mucins, and the mechanisms underlying the oxidative damage they cause. The results indicated that the interaction between DEPM and mucins altered the dispersibility, surface charge, and wettability of the particles, leading to increased release of heavy metals. Protein adsorption experiments and characterizations revealed that the adsorption of mucin by the particles resulted in a complexation reaction between the metals in the DEPM and the mucins, accompanied by fluorescence quenching of the protein. In addition, free radical assays and correlation analyses revealed that environmentally persistent free radicals generated by DEPM induce the production of reactive oxygen species (O 2 ·− , HOOH, and·OH), which damage the secondary structure of mucins and increase the risk of oral diseases. Our study is the first to reveal the interaction between DEPM and mucins in saliva, elucidating the mechanisms of DEPM-induced oxidative damage. This is significant for understanding the oral health risks posed by the ingestion of atmospheric particulate matter.
研究领域:
环境科学
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毒理学
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公共卫生
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化学
✓ 已验证
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）