文献类型：期刊文献

英文题名：Nanosheet MgO-Based CO2 Sorbent Promoted by Mixed-Alkali-Metal Nitrate and Carbonate: Performance and Mechanism

作者：Wang, Lei[1];Zhou, Zhiming[1];Hu, Yuanwu[1];Cheng, Zhenmin[1];Fang, Xiangchen[2]

机构：[1]East China Univ Sci & Technol, State Key Lab Chem Engn, Shanghai 200237, Peoples R China;[2]SINOPEC, Fushun Res Inst Petr & Petrochem, Fushun 113001, Peoples R China

年份：2017

卷号：56

期号：20

起止页码：5802

外文期刊名：INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH

收录：;EI(收录号：20172503805894);WOS:【SCI-EXPANDED(收录号:WOS:000402498900004)】；

基金：Financial support from the National Natural Science Foundation of China (No. 21276076), the Program for New Century Excellent Talents in University (No. NCET-13-0801), the Fundamental Research Funds for the Central Universities (No. 222201718003) and the "111" Project (No. B08021) is gratefully acknowledged.

语种：英文

外文关键词：Magnesia - Nitrates - Carbon dioxide - Metals - Precipitation (chemical) - Sorption - Sodium Carbonate - Potassium Nitrate - Sorbents - Lithium compounds - Nanosheets

摘要：A series of nanosheet MgO-based sorbents promoted by mixed-alkali-metal nitrate and carbonate were prepared by a simple precipitation-deposition method and applied to CO2 capture. The structural properties of these sorbents were characterized by various techniques, and their CO2 capture performance was evaluated using a thermogravimetric analyzer. Compared to the sorbent derived from commercial MgO, the nanosheet MgO-based sorbent had faster and higher CO2 uptake, because of its thin-sheet structure. Among various alkali-metal-salt-promoted nanosheet MgO, the sorbents promoted with mixed-alkali-metal nitrates (LiNO3 and KNO3) and carbonates (Na2CO3 and K2CO3) exhibited a high total CO2 uptake at a respectable rate. In particular, the sorbent with a MgO content of 73 wt % and a nitrate/carbonate molar ratio of 2 possessed the highest total CO2 uptake and the best cyclic stability, with a total uptake of 0.52 g(CO2)/g(sorbent) and MgO conversion of 65% after 20 cycles (60 min of absorption in 40% CO2/60% N-2 at 350 C, 15 min of regeneration in 100% N-2 at 400 C). Based on the structure-activity relationship of the sorbents, a possible mechanism consisting of three stages was presented for the CO2 absorption process, in which the dissolution of CO2 and carbonation in the molten nitrate played an important role.