Steam Reforming of Methane in a Novel Microreactor
Pankaj V. Mathure, Anand V. Patwardhan, and Ranajit K. Saha. Department of Chemical Engineering, Indian Institute of Technology, Faculty, Kharagpur, 721302, India
Almost 90% of industrial hydrogen manufactured today is produced by steam reforming of natural gas as this is by far the most efficient process available. The objective of this article is to review recent trends in steam reforming of methane and natural gas and identify possible strategies for use of novel small dimension reactors for the same process. The focus of our work is on the development of novel micro channeled monolithic reactors which can be coated with suitable catalysts and used for steam reforming of methane. The paper presents the performance characteristics of such a novel microreactor. The structured catalyst called PS–CAT is a cordierite based monolithic structure coated with nickel oxide. The testing was carried out by varying the process parameters such as temperature (673 to 1048 K), molar ratio of steam to methane in the feed (from 2.5:1 to 7:1), space time (W/FCH4 = 10 to 55.0 gm–cat min/mol). The catalyst exhibited good conversion (above 90%) of methane for a molar ratio of steam to methane from 2.5 to 7. Maximum hydrogen yield of 3.8 mol of H2/mol of CH4 reacted was observed at a W/FCH4 of 55.1 gm–cat min/mol at a temperature of 1048 K and molar ratio of steam to methane of 3.0. The performance of this developed catalyst was compared with the performance of commercial nickel–based catalyst in small diameter (3 mm and 6 mm) fixed bed reactors. The catalyst exhibited a minimum increase of 10% and a maximum increase of 22% in the conversion of methane over the commercial catalyst.