Enhanced durability and reactivity for zinc ferrite desulfurization sorbent. Volume 2. Single particle kinetic studies of sulfidation and regeneration reactions of candidate zinc ferrite sorbents: Final report.

摘要

The sulfidation and regeneration kinetics of approximately 35 formulations of zinc ferrite sorbent supplied by AMAX were tested in a single pellet electrobalance reactor. A typical 1-1/2-cycle test consisted of first-cycle reduction, first-cycle sulfidation, first-cycle regeneration, second-cycle reduction, and second-cycle sulfidation. Standard sulfidation conditions were chosen to be 1022(degree)F (550(degree)C) using a simulated coal-gas composition containing 2.7 volume percent H(sub 2)S. Standard regeneration conditions chosen were 1202(degree)F (700(degree)C) in a gas composed of 4 percent O(sub 2), 66 percent N(sub 2), and 30 percent H(sub 2)O (all volume percent). The reduction portion of the cycle was carried out at 1022(degree)F (550(degree)C) using the H(sub 2)S-free sulfidation gas. In addition to the single pellet tests conducted at standard conditions, selected formulations were tested using lower regeneration temperatures of 1202 and 1112(degree)F. Formulation variables considered in preparing the zinc ferrite sorbents included: ZnO-to-Fe(sub 2)O(sub 3) stoichiometric ratio; Fe(sub 2)O(sub 3) grade; binder; shape; and induration conditions.