Hydrogen separation by ceramic membranes in coal gasification. Final report
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 Institute of Technology (CalTech), 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
- Resource Relation:
- Other Information: PBD: Aug 1993
- Country of Publication:
- United States
- Language:
- English
Similar Records
Silica membranes for hydrogen separation in coal gas processing. Final report, January 1993
Synthesis of hydrogen permselective SiO sub 2 , TiO sub 2 , Al sub 2 O sub 3 , and B sub 2 O sub 3 membranes from the chloride precursors
Related Subjects
37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
HYDROGEN PRODUCTION
COAL GASIFICATION
MEMBRANES
CHEMICAL PREPARATION
SEPARATION PROCESSES
CERAMICS
AMMONIA
VYCOR
OXIDES
CHEMICAL VAPOR DEPOSITION
PERMEABILITY
SILICON OXIDES
PERFORMANCE TESTING
EVALUATION
PROGRESS REPORT
080107
400105
SEPARATION PROCEDURES