An improved core-in-shell sorbent for desulfurizing hot coal gas

Work on an advanced calcium-based sorbent for desulfurizing hot coal gas has led to the development of a unique material in the form of spherical pellets, which have a limestone-based core encased in a strong supporting shell. Strong pellets are prepared by incorporating some calcium aluminate cement in the core and a larger amount in the shell, together with limestone. The pellets are prepared by a two-step pelletizing method, followed by steam curing and heat treatment. The pellets are capable of absorbing relatively large amounts of hydrogen sulfide at high temperature (e.g. 1150-1200 K) and can be regenerated by a cyclic oxidation and reduction process. (C) 2002 Elsevier Science Ltd. All rights reserved.