Oxidative Regeneration of Hydrotreating Catalysts Using a Laser Reactor

Abstract An experimental reactor system is described for regenerating deactivated hydrotreating catalysts through oxidative coke burn-off using laser radiation. The laser reactor was designed to process batches of catalyst extrudates using a rotating bed principle involving sequential particle irradiation and agitation steps. The catalyst regeneration system contained dual CO 2 laser and agitation units to enhance processing efficiency. The experimental reactor was used to carry out a systematic study involving laser regeneration of spent commercial catalyst samples from an industrial hydrotreating unit. Carbonaceous deposits on the catalyst surface were removed by the photo-thermally induced chemical reaction of coke molecules with an oxidizing gas mixture. The unique properties of laser heating should reduce the deleterious effects of conventional coke burn-off such as sintering and metals agglomeration. A parametric study of the regeneration process was undertaken using an established experimental design procedure. Important processing parameters were found to be laser intensity, residence time, oxygen concentration, and gas flow rate.