Hydrogen Production Via Oxidative Steam Reforming Of Methanol Over A Zn-Cr Catalyst

The combined reforming of methanol (CRM) is one of the most promising routes for onboard hydrogen production from methanol due to its high efficiency. The current investigation of hydrogen production from methanol mainly focuses on Cu-based and Pd-based catalysts. However, they are not suitable for hydrogen production because Cu-based catalysts deactivate quickly and Pd-Zn catalysts are too expensive. Our studies showed that the Zn-Cr catalyst was a potential catalyst for hydrogen generation by CRM due to its high stability and selectivity.The catalytic performance of a solid solution Cr2O3/ZnO for steam reforming of methanol (SRM) was studied in this thesis, using a microchannel reactor. The results showed that ZnO is the active site and the addition of Cr promoted the activity and selectivity of the catalyst, which could be attributed to the formation of ZnCr2O4 spinel. However, increasing Cr content resulted in increasing CO selectivity.The reaction networks of the SRM and CRM processes over the Zn-Cr catalyst were first ascertained by investigating partial oxidation of methanol (POM), SRM, CRM and water gas shift (WGS) and so on. The reaction kinetics of SRM and CRM were then studied using a stainless steel microchannel reactor, based on the reaction network. The results indicated that the SRM process should include two independent overall reactions, Decomposition of methanol (DM) and SRM. The WGS and reverse WGS reactions could be ignored in the reaction network.