Experimental and DFT Mechanistic Study of Dehydrohalogenation of 1-Chloro-1,1-difluoroethane over Metal Fluorides,Industrial & Engineering Chemistry Research

当前位置： X-MOL 学术 › Ind. Eng. Chem. Res. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Experimental and DFT Mechanistic Study of Dehydrohalogenation of 1-Chloro-1,1-difluoroethane over Metal Fluorides
Industrial & Engineering Chemistry Research ( IF 3.8 ) Pub Date : 2019-09-19 , DOI: 10.1021/acs.iecr.9b03976
Wenfeng Han ₁ , Bing Liu ₁ , Yikun Kang ₂ , Zhikun Wang ₁ , Wei Yu ₁ , Hong Yang ₁ , Yongnan Liu ₁ , Jiaqin Lu ₁ , Haodong Tang ₁ , Ying Li ₁ , Weiyu Song ₂

Affiliation

Vinylidene fluoride (VDF) is one of the major fluorinated monomers. Currently, it is produced via the pyrolysis of 1-chloro-1,1-difluoroethane at above 650 °C without any catalyst. Herein, we propose that metal fluorides are promising catalysts that selectively promote the pyrolysis at 300–450 °C. With various metal fluorides as the catalysts, the conversion rate increases with the amount of acidic sites, which is also reinforced by the Bader charges q. The affinity to Cl of the metal fluorides is responsible for the selectivity. However, the high affinity to Cl also leads to the chlorination of metal fluorides forming metal chlorides followed by the deactivation of the catalyst. Different from other metal fluorides, F defects play a major role in the performance of AlF₃. With an increase in F defects, the selectivity changes from vinylidene chlorofluoride (dehydrofluorination) to VDF (dehydrochlorination), which further confirms the role of affinity to Cl in the selectivity.

中文翻译：

金属氟上1-氯-1,1-二氟乙烷脱卤化氢的实验和DFT机理研究

偏二氟乙烯（VDF）是主要的氟化单体之一。目前，它是通过在没有任何催化剂的情况下，在650°C以上的温度下热解1-氯-1,1-二氟乙烷而制得的。本文中，我们认为金属氟化物是有前途的催化剂，可以选择性地促进300-450°C的热解。在使用各种金属氟化物作为催化剂的情况下，转化率随酸性位点的数量增加而增加，这也由Bader电荷q增强。金属氟化物对Cl的亲和力决定了选择性。然而，对Cl的高亲和力还导致金属氟化物氯化形成金属氯化物，随后使催化剂失活。与其他金属氟化物不同，F缺陷在AlF ₃的性能中起主要作用。随着F缺陷的增加，选择性从亚乙烯基氯氟化物（脱氟化氢）变为VDF（脱氯化氢），这进一步证实了对Cl的亲和力在选择性中的作用。

更新日期：2019-09-20

点击分享查看原文

点击收藏

阅读更多本刊新发论文本刊介绍/投稿指南