JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2022
·
IF 9.965
Minghu Zhao,Jiuhu Zhao,Ran Ding,Rongshu Zhu,Haiyan Li,Zhi Li,Jingwen Zhang,Yongji Zhu,Huiying Li
The existence of sulfur dioxide and water vapor in the flue gas generated from waste-to-energy stations could lead to catalyst deactivation , which has adverse effects on NO x removal. It is thus particularly important to study the reaction mechanism of catalyst resistance to poisoning. Herein, we report the mechanism of In-Co 3 O 4 -Ga 2 O 3 /H-Beta catalyst to SO 2 and H 2 O resistance in the selective catalytic reduction (SCR) of NO x by CH 4 . The catalyst could achieve 74.6% NO x removal efficiency in the presence of 100 ppm SO 2 and 5% H 2 O. In this catalyst, Co 3 O 4 is attributed to enhancing the reversible poisoning of SO 2 and CH 4 activation and increasing the number of Brønsted acid sites by decomposing H 2 O. However, the InO + active center was still eroded by a small amount of water vapor, leading to a reduction in NO x removal efficiency. The addition of Ga 2 O 3 primarily provided an important intermediate NO 2 for CH 4 -SCR reaction and reduced the aggregates of Co 3 O 4 to increase the exposure of indium sites, and could reduce a part of SO 2 to S 2− . This study provides a good candidate for preparing catalysts with superior resistance towards SO 2 and H 2 O for CH 4 -SCR.
研究领域:
环境科学
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催化化学
✓ 已验证
DOI
高影响因子
Chemical Engineering Journal Advances
·
2020
·
IF 0
Jiuhu Zhao,Zhengzhong Wen,Rongshu Zhu,Zhi Li,Ran Ding,Yongji Zhu,Tingkun Gu,Rong Yang,Zhenye Zhu
In this paper, In-metal oxide/H-Beta catalysts were synthesized by ion exchange method and In-Co 3 O 4 /H-Beta exhibited the highest catalytic activity for the selective catalytic reduction of NO x with CH 4 in presence of H 2 O and SO 2 . Thus, the synthesis conditions of In-Co 3 O 4 /H-Beta were optimized. The results showed that In-Co 3 O 4 /H-Beta exhibited excellent catalytic performance and high CH 4 selectively when the synthesis was carried out by ion exchange method, the ratio of Si and Al in H-Beta was 25, the ratio of Co 3 O 4 and H-Beta was 5:40, the concentration of ion exchange liquid was 0.033 M and calcination temperature was 500 °C. The NO x removal efficiency was about 87.6 % and N 2 selectivity could reach 96.3% in the presence of H 2 O and SO 2 . Through a series of characterizations, it was concluded that In-Co 3 O 4 /H-Beta owned stable catalyst structure, abundant Brønsted acid sites and the highest ratio of InO + /In 2 O 3 under the optimal synthesis conditions. In addition, the doped of Co 3 O 4 could inhibit the adsorption of sulfate species on the surface of In/H-Beta catalyst, leading to the excellent H 2 O and SO 2 resistance property.
研究领域:
环境科学
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催化化学
✓ 已验证
DOI
JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY
·
2019
·Vol. 95
·期 3
·798-805
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IF 2.659
Dan Luo,Shengnan Liu,Wang Yin,Shuqian Xia
BACKGROUND Fast pyrolysis of lignocellulosics has provided an abundant sugar source for production of value-added chemicals, and levoglucosan is the most representative sugar in pyrolysis liquid (bio oil). This paper explored the potential for producing methyl lactate from levoglucosan by employing the mixed catalysts of zeolite tin beta (Sn-Beta) and zeolite hydrogen beta (H-Beta). RESULTS Under the optimal conditions (at 200 °C and mixed catalysts with H-Beta:Sn-Beta ratio of 1:5), the yield of methyl lactate obtained from levoglucosan conversion was as high as 35%. And the yield was comparable to that of methyl lactate obtained from glucose conversion under the similar conditions (at 200 °C and pure Sn-Beta). In order to investigate the reason, a contrasting experiment with glucose as substrate also was carried out with the mixed catalysts. The results indicated that during the levoglucosan conversion process, ‘the methanolysis of levoglucosan’ was likely to compete with ‘the dehydration of glucose’ for the Brønsted acid sites of H-Beta. In addition, the catalytic functions of H-Beta and Sn-Beta, and the reaction pathway were deeply investigated through tracking and comparing the conversion of levoglucosan over mixed H-Beta/Sn-Beta and over pure Sn-Beta catalysts, respectively. CONCLUSION The appropriately lower ratio of H-Beta:Sn-Beta and relatively higher temperature were favorable for the reaction. H-Beta containing Brønsted acid could remarkably accelerate the conversion of levoglucosan and methyl-glucosides to glucose. Sn-Beta containing Lewis acid mainly promoted the retro-aldol condensation of glucose and formation of methyl lactate. © 2019 Society of Chemical Industry
研究领域:
化学工程
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生物质能
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催化化学
✓ 已验证
DOI
高影响因子
CHEMOSPHERE
·
2020
·
IF 5.778
Jiuhu Zhao,Gaige Zhang,Jiansheng He,Zhengzhong Wen,Zhi Li,Tingkun Gu,Ran Ding,Yongji Zhu,Rongshu Zhu
In/H-Beta catalyst was prepared by optimizing the support, concentration of ion exchange liquid and calcination temperature to investigate the effects of synthesis conditions on catalytic activity of selective catalytic reduction of NO x with CH 4 . The results showed that the In/H-Beta catalyst exhibited the superior activity when concentration of exchange liquid was 0.033 M and calcination temperature was 500 °C, the NO x removal ratio could reach 97.6%. In addition, reaction conditions could affect the catalytic performance. When O 2 concentration was 10%, CH 4 :NO ratio was no less than one, space velocity was lower than 23600 h −1 and NO initial concentration was no more than 700 ppm, In/H-Beta could exhibit superior catalytic activity. Moreover, the catalytic performances of In/H-Beta catalysts were discussed after enduring H 2 O or/and SO 2 . This novel strategy could open the door for selective catalytic reduction of NO x with CH 4 .
研究领域:
环境科学
·
催化化学
✓ 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）