SEPARATION AND PURIFICATION TECHNOLOGY
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2023
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IF 8.6
Menglei Mao,Feixue Sun,Ruqing Chong,Rui Gao,Qiyong Liao,Zihui Meng,Xinlong Fan,Wenfang Liu
Ti 3 C 2 T x as a typical MXene material has a multilayer structure similar to accordion, whose interlayer spacing and specific surface area can be regulated by intercalation and modification. In this work, the effects of several kinds of cation-containing intercalators including NH 4 OH, KOH and NH 4 OH/KCl on the structure of Ti 3 C 2 T x and its application performance in enzymatic CO 2 conversion were investigated for the first time. The results show that Ti 3 C 2 T x intercalated with NH 4 OH/KCl had larger layer spacing (25.25 Å) and specific surface area (20.85 m 2 /g), and better enhancing effect. The initial reaction rate was 0.379 mM/h, which was separately 1.04, 1.42, 1.76 and 5.29 times that of Ti 3 C 2 T x /KOH, Ti 3 C 2 T x /NH 4 OH, Ti 3 C 2 T x and the blank system. Following that, Ti 3 C 2 T x /NH 4 OH/KCl was modified by polyethyleneimine (PEI) and dopamine (DA) and the concentration of modifier was optimized. PEI modified Ti 3 C 2 T x /NH 4 OH/KCl (PEI-Ti 3 C 2 T x ) was superior to PEI/DA modified that in the N content, CO 2 adsorption capacity and application performance. With the addition of 20 mg PEI-Ti 3 C 2 T x , the initial reaction rate was 0.658 mM/h, which was 1.74 and 9.2 times that of before modification and the blank system, respectively. PEI-Ti 3 C 2 T x also exhibited a good reusability and the initial reaction rate was 89.4% of the initial value after 10 cycles.
研究领域:
材料科学
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环境科学
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生物化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Cleaner Production
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2024
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IF 9.7
Menglei Mao,Ruqing Chong,Feixue Sun,Rui Gao,Zihui Meng,Xinlong Fan,Wenfang Liu
Enzymatic conversion of CO 2 to formate is a highly significant pathway for CO 2 utilization, but current level of conversion efficiency remains unsatisfactory due to low solubility of CO 2 under mild conditions. CO 2 -philic materials can significantly augment the reaction by raising local concentration of substrate. Herein, the intercalated Ti 3 C 2 T x , nano-silica (SiO 2 ) and carbon nitride (CN) with abundant CO 2 adsorption sites were introduced to fabricate Ti 3 C 2 T x based nanocomposites, Ti 3 C 2 T x /SiO 2 /CN (TSCN), for the first time. As the controls, binary composites including Ti 3 C 2 T x /SiO 2 (TS), Ti 3 C 2 T x /CN (TCN) and SiO 2 /CN (SCN) were also studied. For each kind of material, the composition, structure, morphology, and application performance in the enzymatic CO 2 conversion were characterized and influencing factors were investigated. Among these composites, TSCN exhibited the best application performance and the enzyme reaction was accelerated up to 23.9 times that of the blank system. The value could reach as high as 35.3 after polyethyleneimine (PEI) modification. Following that, PEI modified composites were used as carrier of formate dehydrogenase (FDH) and apparent specific activity was up to 2.8 times that of free enzyme, which could retain 88.2% of the initial value after 10 cycles associated with the structural integrity. This work provides new impetus to CO 2 capture and conversion in a clean and mild way that shows bright application prospects.
研究领域:
材料科学
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环境科学
·
化学工程
·
生物技术
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2024
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IF 8.1
Ruqing Chong,Lingding Meng,Qiyong Liao,Zihui Meng,Wenfang Liu
Enzymatic CO 2 conversion represents a highly efficient, energy-conserving, and environmentally sustainable approach to mitigating the increasing pressure caused by huge carbon emissions and generating valuable products. However, several challenges associate with the process including the instability and recovery difficulty of free enzyme, as well as low solubility of CO 2 in mild conditions. Immobilizing enzyme on the amino-functionalized supports presents a viable solution to these issues. Considering the wide application of polymer hollow fiber membranes in the field of CO 2 gas–liquid membrane contactor and the characteristics of hydrophilic, biocompatible, and high specific surface area of silica nanoparticles, the amino-functionalized polyethylene (PE)-silica (APS) composite membranes were fabricated via different routes. The morphologies, the loading rates of modified SiO 2 and reusability of APS membranes were characterized for a crude screening. Following that, seven kinds of APS membranes were used as the carriers of formate dehydrogenase (FDH) that could catalyze the reduction of CO 2 to formate, and their immobilization efficiency and catalytic performance were compared. The results show that 1# and 2# membranes based on carboxyl-modified PE with a loading rate of 5.5 %∼5.6 % and the reusability of above 99 % were more ideal carriers than others. The enzyme activity recovery rate of APS-immobilized FDH (FDH-APS) was separately 367 % and 256 %, proving the intensification action of carriers on the enzymatic reaction. After 10 cycles of use, the relative activity of two kinds of FDH-APS was around 70 % and 78 %, much higher than corresponding particles or membrane attached FDH (25.3 % and 20.4 %). After storage at 4 °C for 20 days, the relative activity of FDH-APS was 82.7 % and 81.0 %, while it was only 61.4 % for free enzyme.
研究领域:
材料科学
·
生物技术
·
环境工程
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）