Hydrogen separation by ceramic membranes in coal gasification. Final report

Technical Report · Sun Aug 01 04:00:00 EDT 1993

DOI:https://doi.org/10.2172/10179996· OSTI ID:10179996

Gavalas, G R

The general objective of this project was to develop hydrogen permselective membranes for hydrogen production from coal gas. The project consisted of the following tasks: (i) membrane preparation and characterization, (ii) membrane stability testing, and (iii) analysis and economic evaluation of a membrane-assisted ammonia from coal process. Several oxides (SiO{sub 2}, TiO{sub 2}, Al{sub 2}O{sub 3}, B{sub 2}O{sub 3}) in dense (or nonporous) form were identified to be permselective to hydrogen at elevated temperatures. To obtain reasonable permeance it is necessary that the membrane consists of a thin selective layer of the dense oxide supported on or within the pores of a porous support tube (or plate). Early in the project we chose porous Vycor tubes (5mm ID, 7 mm OD, 40 {Angstrom} mean pore diameter) supplied by Corning Inc. as the membrane support. To form the permselective layer (SiO{sub 2}, TiO{sub 2}, Al{sub 2}O{sub 3}, B{sub 2}O{sub 3}) we employed chemical vapor deposition using the reaction of the chloride (SiCl{sub 4}, etc.) vapor and water vapor at high temperatures. Deposition of the selective layer was carried out in a simple concentric tube reactor comprising the porous support tube surrounded by a wider concentric quartz tube and placed in an electrically heated split tube furnace. In one deposition geometry (the opposing reactants or two-sided geometry) the chloride vapor in nitrogen carrier was passed through the inner tube while the water vapor also in nitrogen carrier was passed in the same direction through the annulus between the two tubes. In the other (two-sided) geometry the chloride-containing stream and the water-containing stream were both passed through the inner tube or both through the annulus.

• Research Organization: California Inst. of Tech., Pasadena, CA (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC21-90MC26365
• OSTI ID: 10179996
• Report Number(s): DOE/MC/26365--3423; ON: DE93000290
• Country of Publication: United States
• Language: English

Related Subjects

08 HYDROGEN
080107
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400105
AMMONIA
CERAMICS
CHEMICAL PREPARATION
CHEMICAL VAPOR DEPOSITION
COAL GASIFICATION
EVALUATION
HYDROGEN PRODUCTION
MEMBRANES
OXIDES
PERFORMANCE TESTING
PERMEABILITY
PROGRESS REPORT
SEPARATION PROCEDURES
SEPARATION PROCESSES
SILICON OXIDES
VYCOR