The role of boron sites in side-chain alkylation of toluene with methanol and a high performance composite catalyst,Catalysis Science & Technology

当前位置： X-MOL 学术 › Catal. Sci. Technol. › 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.)

The role of boron sites in side-chain alkylation of toluene with methanol and a high performance composite catalyst
Catalysis Science & Technology ( IF 4.4 ) Pub Date : 2020-05-18 , DOI: 10.1039/d0cy00232a
Peidong Li _{1,

2,

3,

4,

5} , Qiao Han _{1,

2,

3,

4,

5} , Yangyang Yuan _{1,

2,

3,

4,

5} , Xiaomin Zhang _{1,

2,

3,

4,

5} , Hongchen Guo _{5,

6,

7,

8} , Lei Xu _{1,

2,

3,

4,

5}

Affiliation

Side-chain alkylation of toluene with methanol has attracted interest for decades as a one-step alternative pathway to manufacture styrene under mild conditions, and a high performance catalyst is most urgently needed to realize the commercial application of this technology. Herein, we studied the role of boron sites in improving the styrene/ethylbenzene ratio (ST/EB) in the products primarily. It was found that the introduction of boron sites into cesium ion exchanged zeolite X (CsX) is helpful in adsorbing and stabilizing the generated formaldehyde from methanol dehydrogenation over the base sites of CsX, and this mainly accounts for the inhibition of further conversion of styrene into ethylbenzene in the side-chain alkylation products. Moreover, it was found that the catalytic performance of the CsX-based catalyst with boron sites was influenced tremendously by the distance between the boron sites and the base sites of CsX. Introducing boron sites into the CsX-based catalyst by grinding boric acid impregnated SiO₂ (B/SiO₂) and CsX was an efficient way to greatly improve the ST/EB in the side-chain alkylation products. Finally, based on the above findings, a ternary composite catalyst with a high yield of side-chain alkylation products (styrene and ethylbenzene) and high ST/EB, which were 39.45% and 1.81, respectively, was developed by mixing CsX, cesium oxide modified CsX and B/SiO₂ with the grinding route. In addition, the key points for preparing a more efficient catalyst in the future were also discussed and proposed.

中文翻译：

硼位在甲苯与甲醇和高性能复合催化剂的侧链烷基化中的作用

甲苯与甲醇的侧链烷基化作为在温和条件下生产苯乙烯的一步替代途径已引起人们的关注，数十年来，为实现该技术的商业应用，迫切需要高性能催化剂。本文中，我们主要研究了硼位在提高产品中苯乙烯/乙苯比（ST / EB）中的作用。发现将硼位引入铯离子交换沸石X（CsX）有助于吸附和稳定由甲醇脱氢在CsX的位点上生成的甲醛，这主要是因为抑制了苯乙烯进一步转化为苯乙烯乙苯在侧链烷基化产物中。此外，结果发现，具有硼位点的CsX基催化剂的催化性能受到CsX的硼位点和碱位点之间距离的极大影响。通过研磨浸渍硼酸的SiO将硼位点引入CsX基催化剂₂（B / SiO₂）和CsX是大大提高侧链烷基化产物中ST / EB的有效方法。最后，基于上述发现，通过混合CsX，氧化铯，开发了具有高收率的侧链烷基化产物（苯乙烯和乙苯）和高ST / EB的三元复合催化剂，分别为39.45％和1.81。用研磨路线改性的CsX和B / SiO₂。此外，还讨论并提出了未来制备更高效催化剂的要点。

更新日期：2020-07-06

点击分享查看原文

点击收藏

阅读更多本刊最新论文本刊介绍/投稿指南11