Abstract: A process deals with gaseous by-products and tarry materials during formation of sol-gel bodies. Gaseous products from a dehydroxylation reactor pass into a gas-fluid contactor. During the early stages of heat treatment, an aqueous acid solution is recirculated through the contactor to trap basic and/or water soluble organic gaseous materials. The resultant solution and non-condensing gases pass into a reservoir. Volatile, undissolved organics exit from the reservoir with non-condensing reactor gases and are treated. Once the organics have burned out of the sol-gel body, recirculation of the aqueous acid solution is ceased, and the gas-fluid contactor is flushed. The water flow is then ceased and dry nitrogen is provided to the contactor. During the next stage of the sol-gel heat treatment, gaseous products from the dehydroxylation reactor pass through the contactor into the caustic scrubber. Once the heat treatment is complete, the contactor is flushed.