FUEL
·
2023
·
IF 7.4
Lin-Cong He,Hua-Hui Xu,Xing-Yue Leng,Ling-Yun Jin,Ai-Ping Jia,Meng-Fei Luo,Jian Chen
Selective catalytic oxidation of nitrogen containing volatile organic compounds (NVOCs) is very meaningful but still remains big challenge because it is very difficult to balance the oxidation activity and N 2 selectivity of available catalysts. In order to develop excellent catalysts with high N 2 selectivity in wide temperature window ( △T ) during NVOCs oxidation, CeO 2 modified CuO/ZSM-5 catalysts with different CeO 2 addition order were prepared for diethylamine (DEA) oxidation. Detailed characterizations of catalysts such as XRD, XPS, H 2 -TPR and NH 3 -TPD were conducted, it is found that addition of CeO 2 obviously changes the geometrical and electronic states of CuO active sites in the catalyst, and CeO 2 addition order affects the Ce 3+ ratio on the catalyst surface. Promotion of CeO 2 species enables the generation of more highly active Cu species (Cu + species and finely dispersed CuO clusters) for DEA oxidation; and synergistic catalysis of the Ce 3+ species, active Cu species and acid sites in ZSM-5 leads to the high N 2 selectivity in wide temperature window ( △T ). Compared to the CeO 2 /CuO/ZSM-5 and CuO-CeO 2 /ZSM-5 catalysts, the CuO/CeO 2 /ZSM-5 catalyst exhibits moderate high oxidation activity with T 99 of 230 °C and the widest △T of 150 °C for high N 2 selectivity. Our primary results in this work provide the efficient strategy for improving catalyst employed for NVOCs selective oxidation.
研究领域:
催化化学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of the Taiwan Institute of Chemical Engineers
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2018
·
IF 3.849
Yue Zhou,Huiping Zhang,Ying Yan
A series of CuO/ZSM-5 catalysts with different copper loadings were prepared by impregnation (IM) and chemical vapor deposition (CVD) methods, respectively. Their physicochemical properties were investigated by N 2 adsorption/desorption, X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectronic spectra (XPS), temperature-programmed reduction by hydrogen (H 2 -TPR) and temperature-programmed desorption of NH 3 (NH 3 -TPD). The XRD and TEM results demonstrated that the crystallite size of the CuO prepared by CVD method was smaller than that by IM, and the XPS results illustrated that the copper specie was mostly in Cu 2+ state and Cu + co-existed. The performance of catalytic oxidation of ethyl acetate was conducted in the fixed-bed reactor based on CuO/ZSM-5 catalysts. The experimental results showed that the preparation method affected the catalytic activity of CuO/ZSM-5; the CVD catalysts exhibited a higher catalytic activity for ethyl acetate oxidation compared with the IM catalysts at the same copper loadings. Ethanol and acetaldehyde are observed to be the intermediate products in the combustion of ethyl acetate over the synthesized catalysts. The relative amounts of acetaldehyde and ethanol are determined by the selectivity of the catalyst toward acetaldehyde production from ethanol. Particularly, the 3 wt% CVD catalyst showed the best catalytic activity for ethyl acetate oxidation with 90% conversion of ethyl acetate at 235 °C, which was much lower than that of the 3 wt% IM catalyst (278 °C), meanwhile, the intermediate products of the 3 wt% CVD for ethyl acetate oxidation were completely oxidized into CO 2 and H 2 O at temperature as low as 288 °C.
研究领域:
催化化学
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材料科学
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环境工程
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2017
·
IF 4.601
Dongjing Liu,Weiguo Zhou,Jiang Wu
CuO-based and MnO x -based sorbents modified with Ce and La using sol-gel method, were employed for elemental mercury removal at 120–240 °C. The Hg 0 removal activity of Mn 2 O 3 /ZSM-5 can be significantly enhanced by doping 50 at.% Ce or 10 at.% La, the Hg 0 removal efficiency increased by 94% and 71%, respectively. The Hg 0 removal ability of CuO/ZSM-5 subtly improved by addition of 50 at.% Ce or 10 at.% La, the Hg 0 removal efficiency ascended only by 6% and 18%, respectively. The XPS results revealed that Hg 0 transformed to HgO, and CuO (or Mn 2 O 3 ) was reduced to Cu 2 O (or Mn 3 O 4 ), which is in agreement with Mars-Maessen mechanism.
研究领域:
环境科学
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材料科学
✓ 已验证
DOI
高影响因子
WATER SCIENCE AND TECHNOLOGY
·
2016
·Vol. 73
·期 11
·2747-2753
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IF 1.064
Kong Wusong,Qu Hongxia,Chen Peng,Ma Weihua,Xie Huifang
In this study, Cu 2 O-CuO/ZSM-5 nanocomposite was synthesized by the impregnation method, and its catalytic performance for the destruction of AO7 in aqueous solutions was investigated. The morphology, structure and surface element valence state of Cu 2 O-CuO/ZSM-5 were characterized by transmission electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy. The operating conditions on the degradation of AO7 by Cu 2 O-CuO/ZSM-5, such as initial pH values, concentration of AO7 and catalyst dosage were investigated and optimized. The results showed that the sample had good catalytic activity for destruction of AO7 in the absence of a sacrificial agent (e.g. H 2 O 2 ): it could degrade 91% AO7 in 140 min at 25 °C and was not restricted by the initial pH of the AO7 aqueous solutions. Cu 2 O-CuO/ZSM-5 exhibited stable catalytic activity with little loss after three successive runs. The total organic carbon and chemical oxygen demand removal efficiencies increased rapidly to 69.36% and 67.3% after 120 min of treatment by Cu 2 O-CuO/ZSM-5, respectively.
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DOI
高影响因子
CHEMICAL ENGINEERING RESEARCH & DESIGN
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2020
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IF 3.35
Yue Zhou,Huiping Zhang,Ying Yan
CuO/ZSM-5/PSSF was synthesized by a combined wet lay-up papermaking, secondary growth and chemical vapor deposition (CVD) method for the catalytic oxidation of ethyl acetate in the fixed bed reactor. Ethanol and acetaldehyde are found during the oxidation and 3 wt% CuO/ZSM-5/PSSF catalyst exhibited the best performance with 90% conversion of 1500 ppm ethyl acetate at 254 °C with GHSV of 15,000 h −1 , and the CuO/ZSM-5/PSSF exhibits low byproducts selectivity compared to granular CuO/ZSM-5 catalyst. Furthermore, the 3 wt% CuO/ZSM-5/PSSF catalyst exhibits a high stability after being used at 262 °C for 48 h.
研究领域:
化学工程
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材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子