HYDROGEN-PRODUCTION FROM HYDROGEN-SULFIDE USING MEMBRANE REACTOR INTEGRATED WITH POROUS MEMBRANE HAVING THERMAL AND CORROSION-RESISTANCE

Using mathematical model and experimental method, the thermal decompos ition of hydrogen sulfide in membrane reactor with porous membrane whi ch has Knudsen diffusion characteristics was investigated. With mathem atical model, the effect of characteristics of membrane reactor and op erating conditions on H-2 concentration in the permeate chamber, y(H2) , which increases at higher reaction temperature, lower pressure and h igher ratio of cross-sectional area of the permeate chamber to that of the reactor, was evaluated. The reaction experiments with ZrO2-SiO2 p orous membrane were carried out under the following conditions: temper ature T, 923-1023 K; pressure in the reactor p(T)(R), 0.11-0.25 MPa ab solute; pressure in the permeate chamber p(T)(P), 5 kPa absolute and i nlet flow rate of H2S f(H2S)(0), 3.2x10(-5)-1.5x10(-4) mol/s. At p(T)( R)=0.11 MPa and f(H2S)(0)=6.4x10(-5), y(H2) increased from 0.02 at T=9 23 K to 0.15 at 1023 K. With the experimental condition, p(T)(R)=0.11, T=1023 K and f(H2S)(0)=3.2x10(-5), y(H2) was 0.22. The experimental r esults were compared with the results of the mathematical analysis. Th e agreement between both the results is found rather good at a lower r eacting temperature, but not so good at a higher reacting temperature. (C) 1998 Elsevier Science B.V. All rights reserved.