Abstract: Effect of zine silicate on desulfurization activity of S Zorb adsorbent was studied in a fixed bed reactor. The results showed that the sorbents had higher desulfurization activity, and the sulfur breakthrough capacity were more than 12% when there was no zinc silicate in the S Zorb adsorbent. The sorbents had little influence on sorbents desulfurization activity and selectivity when the content of zinc silicate was low. The great increase of zinc silicate content had a significant effect on the sulfur carrying capacity of the adsorbent. When the mass fraction of zinc silicate in the adsorbent was 39.4%, the sulfur breakthrough capacity of the adsorbent was decreased to 2.18%, and the desulfurization activity of the adsorbent was decreased greatly. When the mass fraction of zinc silicate in the adsorbent was low, the adsorbent could maintain high desulfurization rate and high desulfurization selectivity, which could avoid excessive olefin hydrogenation saturation and reduce the octane number loss of gasoline. In addition, the increase of zinc silicate in adsorbent could reduce the desulfurization selectivity of the S Zorb adsorbent and lead to more olefin saturation and RON loss while producing gasoline products with sulfur content below 10 μg/g. Therefore in the operation of S Zorb commercial units, the operating conditions should be controlled to reduce the formation of zinc silicate as much as possible.

Key words: S Zorb, adsorption desulfurization, zinc silicate, deactivation, desulfurization selectivity