Metal loading effects on the stability of Ni-Ru catalysts for hydrogen production from liquid hydrocarbons at high pressure and low temperature

Abstract

Hydrogen has been gaining attention as an important energy carrier in the future. Its cost needs to be reduced to allowits market penetration at an acceptable level. Possible solutions are to use a liquid fuel that lowers transportation costsand to reduce the complexity of the current hydrogen production system. A new process that integrates a pre-reformer(PR) and a membrane reformer (MR) can be considered. The PR operates at high pressure and low temperature toproduce a methane-rich stream from heavy naphtha. It then enters the MR, where methane steam reforming occurs.Hydrogen separation also occurs due to the high-pressure operation and leads to efficient conversion of methane. Thepre-reforming reaction requires a sufficient amount of active metals as well as strong metal-to-support interactions tocrack complex hydrocarbons in the fuel at low temperatures (500 ~ 600 C). In order to gain commercial significance,the pre-reforming catalyst needs to have high enough performance to convert the complex hydrocarbons to themethane-rich stream in a stable manner. In the past, we developed our Ni-Ru/CGO catalyst for low-temperature pre-reforming. Thus, we optimized the metal loading of the catalyst for our specific applications. Experiments wereperformed by changing the nickel and ruthenium contents. The pressure, temperature, steam-to-carbon ratio, andGHSV were 25 bar(g), 550°C, = 3.0, and 100,000 h , respectively. Post-experimental analysis on the catalyst sampleswere performed to investigate the effects of the metal loading. The catalyst had longer duration as its Ni loadingincreased from 19.5 to 49.5 wt%. Our results can be used as a reference for building our proposed system on anindustrial scale.