Controlling the bidirectional chemical environments for high-performance Y@silicalite-1 core-shell composites in shape selective desulfurization

A high-performance Y@silicalite-1 core-shell composite for shape-selective adsorption desulfurization was synthesized by controlling the bidirectional chemical environments via a resin interlayer between Y zeolite core and silicalite-1 shell. In this process, the alkali treatment, Cu2+ ion-exchange, Cu2+ equal volume impregnation, resin coating and ethylenediamine modification were applied to work collaboratively for a high shape selectivity and high sulfur adsorption capacity. Results showed that alkali treatment for 2 h, TEOS:Y = 4, Y:3-aminophenol = 1:1, Y: EDA = 1:1 and 550 degrees C calcination could endow the synthesized core-shell structured composite with a high-performance in shape-selective adsorption desulfurization of DMDS from MTBE solution with a maximum sulfur adsorption capacity of 75.58 mg(s)/g(adsorbents), which was more than double of the best DMDS sulfur adsorption capacity from MTBE (37.07 mg(s)/g(adsorbents)) reported previously. The adsorption kinetic and isotherm analysis indicated that the adsorption of DMDS on Y zeolites was monolayer-chemisorption process, and the corresponding theoretical saturated adsorption capacity could reach up to 84.6 mg(s)/g(adsorbents). The regeneration capability can be effectively improved by ethanol extraction before calcination, retaining a high desulfurization rate level at more than 92% even after 6 cycles.

Automated summary

This study focused on synthesizing a high-performance Y@silicalite-1 core-shell composite for shape-selective adsorption desulfurization. By controlling the chemical environments, a maximum sulfur adsorption capacity of 75.58 mg(s)/g(adsorbents) was achieved, more than double the previous best reported capacity. Additionally, the regeneration capability was effectively improved by ethanol extraction, maintaining a high desulfurization rate level at more than 92% even after 6 cycles.