Patent ID: 7132180

Claim:
In a fuel cell system comprising a reformer to produce a hydrogen containing gas for use in a fuel cell stack, the improvement comprising: feeding to the reformer, during start-up, an emulsion comprising at least 40 wt % hydrocarbon, from 30 to 60 wt % water, and at least one surfactant, wherein the emulsion comprises a bicontinuous micro-heterogeneous emulsion composition comprising a coexisting mixture of: a. at least 80 vol % of a water-in-hydrocarbon macro emulsion having average droplet sizes of dispersed phase droplets greater than about one micron, and b. 1 to 20 vol % of a hydrocarbon-in-water micro emulsion having average droplet sizes of dispersed phase droplets less than about one micron, and c. from 0.01 to 5 wt % of at least one surfactant selected from the group consisting of alkyl sorbitan esters and alkoxylated alkyl sorbitan esters and mixtures thereof, and represented by the respective formulae wherein R is an alkyl group of 5 to 18 carbons, R′ is H or (M—O) n —H where n is an integer from about 2 to 20 and the total number of (M —O) n —H groups per molecule is from 2 to 60, M is CH 2 —CH 2 , CH 2 —CH 2 —CH 2 , CH 2 —CH—CH 3 , CH 2 —CH 2 —CH 2 —CH 2 , CH 2 —CH—(CH 3 )—CH 2 or mixtures thereof.