ITM Syngas - Ceramic Membrane Technology for Lower Cost Conversion of Natural Gas
Publication Date: 2008-Apr-10
The IP.com Prior Art Database
Copyright © 2007 Air Products and Chemicals, Inc.
Prepared for Presentation at the AIChE Fall National Meeting
Salt Lake City,
UTNovember 4-9, 2007
The ITM Syngas Team, led by Air Products and including Chevron, Ceramatec, and other partners, in collaboration with the U.S. Department of Energy, is developing Ion Transport Membrane (ITM) technology for the production of synthesis gas. ITM ceramic membranes are fabricated from non-porous, multi-component metallic oxides and operate at high temperatures (typically over 700°C) with exceptionally high oxygen flux and selectivity. A conceptualization of the ITM Syngas technology is shown in Figure 1. Oxygen from low-pressure air permeates, as oxygen ions, through the ceramic membrane and is consumed through chemical reactions, thus creating a chemical driving force that pulls oxygen ions across the membrane at high rates. The oxygen reacts with natural gas in a partial oxidation process to produce a hydrogen and carbon monoxide mixture (synthesis gas).
Figure 1. Conceptual ITM Syngas process showing multiple synthesis gas applications
The ITM Syngas process is a breakthrough technology that combines air separation and high-temperature synthesis gas generation processes into a single ceramic membrane reactor, with significant savings in the cost of synthesis gas production. Because synthesis gas is a feedstock for a range of different processes, ITM Syngas represents a technology platform that has numerous applications, such as Gas-to-Liquids; hydrogen; ultra-clean fuels, including liquid transportation fuels; and chemicals such as methanol (Figure 1).
Membrane Design and Manufacture
The economics of the ITM Syngas process are most attractive when a high-pressure natural gas feed and a low-pressure air feed are used to produce a synthesis gas product at a high pressure that matches downstream process pressures. This arrangement avoids the expenses associated with compressing the air or the synthesis gas. Ceramic membranes for this application must withstand the stresses generated by the large pressure difference between the high-pressure natural gas/synthesis gas on one side of the membrane and the low-pressure air on the opposite side.
Within the ITM Syngas development program, a planar ceramic membrane was designed and fabricated that is able to achieve high oxygen fluxes while withstanding the thermo-mechanical stresses encountered during operation. The membrane design incorporates micro-channel features to reduce the thermo-mechanical stresses that occur within the membrane assembly because of the pressure loads and...