Boosting the Performance of Alkanes’ Dehydrogenation Catalysts in the Industrial Scale by Altering the Water Injection Strategy

Abstract

Water addition plays a pivotal role in prolonging the catalytic dehydrogenation reactions and normally starts at the beginning of the dehydrogenation process. A delayed water injection strategy is proposed in this study to improve the performance of bimetallic Pt-Sn/Al2O3 catalyst utilized for long-chain alkanes (nC10–C13) dehydrogenation in the industrial scale. The dehydrogenation reactions took place at a pressure of 0.11–0.13 MPa and temperature varied between 470 and 490 °C. Postponing the water supply until the middle of run leads to longer operating life for the catalyst and consequently reduces the production costs significantly. In addition, it promotes the quality of the final product by decreasing the undesired by-products and results in higher production capacities (by 1.5 %) in the industrial scale. Characterization of the deactivated dehydrogenation catalysts using different methods allows the understanding of the boosted performance of the catalyst arising from postponing the water injection process. Moreover, the proposed strategy reduces the waste production by decreasing the ratio of loaded catalyst to the desired product (by 23 %) and thus alleviates the negative environmental impact of the process. Furthermore, it results in lower energy consumption and promotes the mitigation of CO2 gas emissions by 3 % which can be effective in tackling environmental challenges in the large scale.