CATALYSIS TODAY
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2018
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IF 4.667
Xianghui Li,Yingnan Zhao,Huawang Zhao,Mengke Liu,Yuhan Ma,Xin Yong,Hong Chen,Yongdan Li
Two kinds of Cu-SAPO-34 catalysts, prepared with a one-pot technique using Cu- tetraethylenepentamine as co-template and an ion-exchange method, were hydrothermally treated at 750 °C for at least 16 h. The migration of Cu species during hydrothermal treatment and the corresponding effect on the selective catalytic reduction (SCR) of NO x were examined and characterized. A certain amount of CuO exists outside and inner the crystallites in the as prepared ion-exchanged sample, whereas copper is mainly atomically dispersed in the one-pot sample existing as isolated Cu 2+ . After hydrothermal treatment for 16 h, the amount of the inner nanosized CuO in the ion-exchanged sample reduced and the copper disperses to form more isolated Cu 2+ . However, surface CuO particles increase at the sacrifice of isolated Cu 2+ with extending the hydrothermal treatment to 24 h. Aggregation of Cu 2+ species also happens during the aging treatment over the one-pot prepared sample where the initial Cu is atomically dispersed as isolated Cu 2+ . The increase of the amount of the isolated Cu 2+ enhances the low-temperature (< 350 °C) performance. However, the increase of the amount of surface CuO particles in the aged samples promotes the nonselective NH 3 oxidation reaction in the high temperature range and results in the lowering of the SCR activity by limiting NH 3 supply.
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
Waste and Biomass Valorization
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2024
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IF 2.6
Sun Xiaolei,Li Qiao,Shen Jinyou,Han Weiqing,Li Jiansheng,Sun Xiuyun
In this study, we report the co-treatment of municipal solid waste incineration fly ash and high arsenic-containing wastewater. The appropriate liquid-solid ratio for co-treatment and the feasibility of co-treatment with 5000 mg/L arsenic in wastewater were investigated, as well as the risk of heavy metals leaching from the co-treated products in the actual leachate. Further, a new index for assessing the risk of heavy metals releasing into the environment was proposed. The results demonstrated that the optimal liquid-solid ratio was 10 mL/ 20 g, considering that it allowed the maximum co-treatment amount of wastewater and would not affect the subsequent disposal of co-treated products in landfills. In the presence of 5000 mg/L arsenic in wastewater, the chemical speciation distribution and leaching toxicity of As, Cr, Cu, and Pb in the co-treated products would not change significantly. The leaching results of co-treated products in actual leachate indicated that the co-treated products can favor the stabilization of As, Cr, and Pb in leachate. The migration and transformation index value of Cu suggested the risk of Cu releasing in a leachate scenario. Through co-treatment, wastewater can be completely absorbed into the fly ash without the need for further treatment, featuring significant economic and environmental benefits. Graphical Abstract
研究领域:
环境科学
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废弃物管理
✓ 已验证
产品关联
DOI
高影响因子
Innovative Food Science & Emerging Technologies
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2020
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IF 4.477
Yu-Jie Shi,Magdalena Wrona,Chang-Ying Hu,Cristina Nerín
The influences of temperature, exposure time, different types of polypropylene (PP), (3-Aminopropyl) triethoxysilane (KH550) used as coupling agent, sterilizing conditions on copper migration from nano‑copper/PP composite films into food/ food simulants were explored. Results showed that copper migrated more easily from polypropylene (PPH) films with a maximum rate of 34.51%, compared to those from copolymer polypropylene (PPR) and block copolymer polypropylene (PPB) to 3% acetic acid ( w / v ). Gamma (γ) irradiation could significantly increase the copper migration ( P < 0.05). Different forms of copper were found in different simulants. Copper crystals were found in 10% ethyl alcohol and identified by scanning electron microscopy and energy dispersed analysis of X-rays (SEM-EDX). The hydroxylation (%) of nano‑copper/PP films was less than 100%. These films had certain antioxidant and antimicrobial properties which could extend the shelf life of packaged food. The migration amount of copper into rice vinegar was the largest, with a maximum of 0.65 mg/ kg. Industrial relevance Although nanomaterials are potentially beneficial for food packaging, migration of nanoparticles to the packaged food can be harmful to the human body. Therefore, it is very important to determine the presence and characterize the morphology of nanoparticles in food. In this paper, we have developed a new and effective packaging material containing nanoparticles and have explored the migration form and morphology in food simulants. In conjunction with the results of current study, nano‑copper/PP packaging material can be suggested for maintaining the product quality and has commercial potential.
研究领域:
食品科学
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材料科学
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生物医学
✓ 已验证
产品关联
DOI
高影响因子
Food Additives and Contaminants Part A-Chemistry Analysis Control Exposure & Risk Assessment
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2016
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IF 1.878
Fang Liu,Chang-Ying Hu,Quan Zhao,Yu-Jie Shi,Huai-Ning Zhong
Three nanocopper/low-density polyethylene (LDPE) composite films were tested in food simulants (3% acetic acid and 10% ethanol) and real food matrices (rice vinegar, bottled water and Chinese liquor) to explore the behaviours of copper migration using ICP-OES and GFAAS. The effects of exposure time, temperature, nanocopper concentration and contact media on the release of copper from nanocopper/LDPE composite films were studied. It was shown that the migration of copper into 10% ethanol was much less than that into 3% acetic acid at the same conditions. With the increase of nanocopper concentration, exposure time and temperature, the release of copper increased. Copper migration does not appear to be significant in the case of bottled water and Chinese liquor compared with rice vinegar with a maximum value of 0.54 μg mL−1 for the CF-0.25# bags at 70°C for 2 h. The presence and morphology of copper nanoparticles in the films and the topographical changes of the films were confirmed by field emission scanning electron microscope (FE-SEM) and atomic force microscope (AFM). In this manner, copper nanoparticles of different morphologies, sizes and distribution were found, and samples with higher nanocopper concentration had a more irregular topography. In the case of Fourier transform infrared spectroscopy (FTIR), no chemical bonds formed between copper nanoparticles and LDPE. Copper nanoparticles were just as physically dispersed in LDPE.
研究领域:
材料科学
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食品科学
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分析化学
✓ 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）