Highly Selective Conversion of 1‐Butene to 1,3‐Butadiene under CO₂ Atmosphere over an Alumina‐supported Iron‐based Catalyst: The Role of Brønsted Acids and Lewis Acids

Abstract

The conversion of 1-butene to 1,3-butadiene (BD) with CO 2 is burgeoning as a latent technology, but the low BD selectivity of the current catalysts (� 40 %) is now the bottleneck of this process. Herein, an alumina-supported iron-based catalyst with high BD selectivity for the oxidative dehydrogenation of 1butene using CO 2 was designed and prepared, and the BD selectivity has been improved up to 49 %. Consequently, the turnover frequency has been enhanced to 1.5 times that of the current FeVCrO X /γ-Al 2 O 3 catalyst. Furthermore, the effect of the acid type and content in the catalysts on their selectivity was identified. The Brønsted acids in the catalysts leaded to the unwanted isomerization reactions, whereas the Lewis acids played a key role in highly selective transform 1-butene to BD. The BD selectivity increased with the increasing Lewis/Brønsted acids ratio. In addition, the conversion of 1-butene over such catalysts was investigated through kinetic study.