PALLADIUM/COPPER ALLOY COMPOSITE MEMBRANES FOR HIGH TEMPERATURE HYDROGEN SEPARATION FROM COAL-DERIVED GAS STREAMS

Way, J. Douglas ; McCormick, Robert L.

National Energy Technology Laboratory (U.S.)

关键词: 08 Hydrogen;    Alloys;    Embrittlement;    Polymers;    01 Coal, Lignite, And Peat;   

DOI  :  10.2172/795786
RP-ID  :  FG26-99FT40585--01
RP-ID  :  FG26-99FT40585
RP-ID  :  795786

美国|英语

来源: UNT Digital Library

【 摘 要 】

Recent advances have shown that Pd-Cu composite membranes are not susceptible to the mechanical, embrittlement, and poisoning problems that have prevented widespread industrial use of Pd for high temperature H{sub 2} separation. These membranes consist of a thin ({approx}10 {micro}m) film of metal deposited on the inner surface of a porous metal or ceramic tube. Based on preliminary results, thin Pd{sub 60}Cu{sub 40} films are expected to exhibit hydrogen flux up to ten times larger than commercial polymer membranes for H{sub 2} separation, and resist poisoning by H{sub 2}S and other sulfur compounds typical of coal gas. Similar Pd-membranes have been operated at temperatures as high as 750 C. The overall objective of the proposed project is to demonstrate the feasibility of using sequential electroless plating to fabricate Pd{sub 60}Cu{sub 40} alloy membranes on porous supports for H{sub 2} separation. These following advantages of these membranes for processing of coal-derived gas will be demonstrated: High H{sub 2} flux; Sulfur tolerant, even at very high total sulfur levels (1000 ppm); Operation at temperatures well above 500 C; and Resistance to embrittlement and degradation by thermal cycling. The proposed research plan is designed to providing a fundamental understanding of: Factors important in membrane fabrication; Optimization of membrane structure and composition; Effect of temperature, pressure, and gas composition on H{sub 2} flux and membrane selectivity; and How this membrane technology can be integrated in coal gasification-fuel cell systems.