RSC Advances
·
2023
·Vol. 13
·期 23
·15934-15941
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IF 3.9
Xiaoping Chen,Xianfei Wang,Wei Liu,Hui Tian,Yupeng Du,Haisheng Wei,Linsheng Tang
1-Butene, as one of the widely used chemical raw materials, can be produced by the double bond isomerization of 2-butene. However, the current yield of the isomerization reaction is only up to 20% or so. It is therefore an urgent issue to develop novel catalysts with higher performances. In this work, a high-activity ZrO2@C catalyst that is derived from UiO-66(Zr) is fabricated. The catalyst is prepared by calcining the precursor UiO-66(Zr) at high temperature in nitrogen, and characterized by XRD, TG, BET, SEM/TEM, XPS and NH3-TPD. The results demonstrate that the calcination temperature has significant influences on the catalyst structure and performance. Regarding the catalyst ZrO2@C-500, the selectivity and yield of 1-butene are 94.0% and 35.1%, respectively. The high performance is due to multiple aspects, including the inherited octahedral morphology from parent UiO-66(Zr), suitable medium-strong acidic active sites and high surface area. The present work will lead to a better understanding of the ZrO2@C catalyst and guide the rational design of high-activity catalysts for the double bond isomerization of 2-butene to 1-butene.
研究领域:
化学工程
·
催化材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Polymers
·
2023
·Vol. 16
·期 1
·103
·
IF 5
Qiao Zhou,Yuanyuan Zhao,Yafei Shi,Rongrong Zheng,Liying Guo
Utilizing triethylenediamine (DA), 1,3-propanesultone (PS), whose ring opens during the formation of the dizwiterion-intermediate DA-2PS, and the metal chlorides XCly, where X = Sn(IV), Zn(II),Al(III), Fe(III) and Mn(II), are used for the synthesis of five kinds of acidic metal-based functionalized ionic liquid catalysts ([DA-2PS][XCly]2). Their chemical structures, thermal stability and dual acidic active site were analyzed. We investigated the performance of [DA-2PS][XCly]2in catalyzing the esterification reaction between 2,5-furandicarboxylic acid (FDCA) and ethylene glycol (EG) to synthesize poly (ethylene 2,5-furandicarboxylate)(PEF). Among the catalysts tested, [DA-2PS][SnCl5]2exhibited the best catalytic performance under identical process parameters, and the optimal catalyst dosage was determined to be 0.05 mol% based on FDCA. The optimal conditions for the reaction were predicted using response surface methodology: a feed ratio of EG:FDCA = 1.96:1, an esterification temperature of 219.86 °C, a polycondensation temperature of 240.04 °C and a polycondensation time of 6.3 h, with a intrinsic viscosity of 0.67 dL·g−1. The resulting PEF was experimentally verified to exhibit an intrinsic viscosity of 0.68 dL·g−1and a number average molecular weight of 28,820 g·mol−1. Finally, the structure and thermal properties of PEF were characterized. The results confirmed that PEF possessed the correct structure, exhibited high thermal stability and demonstrated excellent thermal properties.
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Huajing Zhou,Huichang Dong,Jinghao Wang,Yuancai Chen
A novel controllable mesoporous core–shell microsphere (Co/Fe 3 O 4 @PZS) is synthesized by polycondensation, and used as ORR electrocatalyst in the heterogeneous electro-Fenton (hetero-EF) reaction. Characteristic analysis indicated that PZS offered massive reactive sites for anchoring Co ions on the shell. Heteroatom Lewis acidic active sites, related with pyridinic N (4.15%), P = N/P-N (6.46%) and S = O (3.19%) bonds, were formed through the replacement of C = C groups with the N-P-S doped at the shell, which benefited the activating/generating reactive oxygen species (ROS), and capturing/degrading the target pollutant substrates. Moreover, PZS shells prevent the nano-Fe 3 O 4 crystals in the core from direct contact with the solution, which would greatly improve the stability of electrode with almost no leaching of Fe/Co ions after six successive runs. Electrochemical experiments confirmed the accelerating electron transfers among ≡Fe II/III /≡Co II/III by the direct electric activation, as evidenced by the decreasing potential discrepancy (from 0.175 to 0.123 V) and sharply increasing ring current (from 35 to 200μA), markedly improved the ORR toward two-electron process (n = 2.01). ESR and radical scavenging experiments verified that •OH and 1 O 2 served as the main ROS in the Co/Fe 3 O 4 @PZS hetero-EF system. In addition to the two-electron reduction ( O 2 → H 2 O 2 → Â · O H ), O 2 could also be directly electro-activated to 1 O 2 via one-electron reduction ( O 2 → Â · O 2 - / Â · HO 2 - → 1 O 2 ). Additionally, the regenerating/reducing of ≡Fe III /Co III could get the electron directly from the cathode without excess consumption of H 2 O 2 , all these could eventually facilitate BPA degradation with lower energy consumption (1.318 kWh m −3 ). This study provides a reliable and facile route to prepare mesoporous core–shell microsphere, and developed as doped cathode in the field of electro-Fenton electrocatalysis process.
研究领域:
环境科学
·
材料科学
·
电化学
·
催化
✓ 已验证
DOI
高影响因子