ACS Sustainable Chemistry & Engineering
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2024
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IF 7.1
Yingyang Song,Junyu Lang,Qingrui Zeng,Jinping Cheng,Mingce Long
Monoethanolamine (MEA)-based carbon dioxide absorption is one of the effective carbon capture, utilization, and storage (CCUS) technologies but is significantly restricted by the high energy consumption in the regeneration of rich amine solution. Solid acid catalysts have the potential to reduce energy consumption, while the exploration of highly active catalysts with abundant Bro̷nsted and Lewis acid sites remains needing. We developed an efficient solid acid catalyst, niobium-modified HZSM-5 (Nb/HZ), to facilitate CO2 desorption from the CO2-captured MEA solutions. The Nb/HZ catalysts with various niobium loadings were synthesized by using an impregnation method. HZSM-5 retained its pore structure and large surface area after niobium incorporation. The catalyst with 4% Nb (4.0-Nb/HZ) has the highest activity and stability, with 61% increase in the desorption rate, 50% increase in the desorbed CO2 amount, and 37% reduction of relative heat duty. According to theoretic calculations and experimental analyses, the Nb/HZ catalyst provides abundant Bro̷nsted and Lewis acid sites to facilitate carbamate adsorption, proton transfer, and carbamate breakdown, thus reducing the activation energy for CO2 desorption. This work provides a valuable solid acid catalyst for amine-based CO2 capture and also brings insights for the development of a novel solid acid for diverse catalysis.
研究领域:
化学工程
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催化科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS A-GENERAL
·
2017
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IF 4.339
Baohuai Zhao,Rui Ran,Xingguo Guo,Li Cao,Tengfei Xu,Ze Chen,Xiaodong Wu,Zhichun Si,Duan Weng
Mn/Ce/Ti and Mn/Ce/Nb/Ti catalysts were synthesized using a precipitation method and their catalytic activities for NO selective reduction with NH 3 at low temperatures were evaluated. Nb doping not only improved the activity of the catalyst over a wide temperature range but also restricted the generation of NO 2 and N 2 O. The Mn/Ce/Nb/Ti catalyst displayed 100% NO conversion from 150 to 250 °C and >90% N 2 selectivity below 250 °C. The specific surface area of the catalyst was increased and its surface acidity was strengthened after Nb doping. Moreover, Nb doping increased the NO oxidation ability and lowered the NH 3 oxidation activity of the catalyst. All the above factors contributed to enhancing the overall NH 3 -SCR performance of the Mn/Ce/Nb/Ti catalyst compared with that of the Mn/Ce/Ti one. The long-term stability and resistance to H 2 O and SO 2 of the Mn/Ce/Nb/Ti catalyst were also evaluated.
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
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2025
·
IF 3.9
Dayu Sun,Panli Liu,Huijun Liu,Zhixiu Yang,Lijing Gao,Ruiping Wei,Xiaomei Pan,Guomin Xiao
Furfural, a promising biobased platform chemical, can be derived from xylan through an acid-catalyzed dehydration process. However, the yield of furfural in the aqueous phase is often limited by side reactions (furfural degradation). Employing a biphasic solvent system for in situ furfural extraction presents a strategy to mitigate furfural degradation as furfural is more stable in some organic phases, reducing the polymerization with reaction intermediates in the aqueous phase. In this study, a novel energy-efficient process was developed for the enhanced production of furfural from corncob xylan in a biphasic solvent system. A series of niobium-modified SBA-15 solid acid catalysts for furfural production were synthesized and characterized to determine the physical properties, structure, and crystallinity. The toluene/H2O biphasic system was selected to intensify the furfural production and reduce subsequent separation costs. The experimental parameters including niobium doping of catalyst, reaction time, reaction temperature, catalyst input, and xylan input were optimized to obtain high furfural yield. The process model for production and purification of furfural was established based on experimental data, and the results demonstrated that the furfural purification section in the proposed process reduced cold energy consumption by 64.08% and heat energy consumption by 70.29% compared to the conventional process.
研究领域:
生物化学
·
催化化学
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能源化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Yihan Tang,Shuaishuai Chen,Ming Wan,Hua Li,Qingliang You,Zhenlian Chen,Zhe Peng,Deyu Wang
Ni-rich layer-structured materials are some of the most promising cathodes owing to their attractive reversible capacity and cost-effectiveness. When the Ni content is increased to 90% and higher, mechanical deterioration becomes serious and leads to accelerated cyclic degradation, since removable Li+ is ∼0.85, accompanied by large lattice variation during operation. Here, we investigate the influences of Ti4+ bulky substitution, Nb5+ surface treatment, and their coutilization on the behavior of LiNi0.925Co0.065Mn0.01O2 (NCM92). In contrast to the limited positive effects of monousage, the coutilization of Ti4+ and Nb5+ obviously suppresses particles’ pulverization, relying on their synergistic effects of the shape of lattice variation and the protection of a tough shell layer. As a result, Ti & Nb-LiNi0.925Co0.065Mn0.01O2 (TiNb-NCM92) presents the best capacity retention, as high as 90.2% after 300 cycles, much higher than NCM92 (49.0%), Ti-NCM92 (76.3%), and Nb-NCM92 (72.4%). Our approaches demonstrate that the serious mechanical challenges of ultrahigh nickel cathodes could be alleviated by various remedies coutilized together.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）