New nano-structured materials for nitric oxide/ammonia abatement, desulfurization and hydrogen storage.

Abstract

Nanoporous materials as catalysts and adsorbents with unique surface chemistry have high surface areas and unique morphologies, which influence catalytic behavior and adsorption capacity. This property provides scope of the synthesis and screening of new nanomaterials for catalytic reaction, adsorption and storage. This dissertation discusses the synthesis, characterization and evaluation of several nano-structured materials for nitrogen oxides, ammonia emission control by selective catalytic reaction, desulfurization from liquid fuel and natural gas and hydrogen storage applications. These materials include iron exchanged zeolite, mixed cerium-manganese oxides, titania support ironmanganese, titanium-pillared clay support palladium, vanadium modified titanium-alumina support palladium, copper salts dispersed on alumina, pi-complex sorbents, such as silver and copper exchanged zeolite and active carbon/carbon nanotube. Fe-ZSM-5 prepared by several methods was examined for high temperature SCR of NO with ammonia and a cheaper method used for preparation of Fe-ZSM-5 with high activity was found. Mixed oxides were tailored for low temperature SCR of NO with ammonia. Cerium-manganese oxides were found to exhibit superior activity for this reaction. The SCR of NO with hydrogen in the presence of excess oxygen was studied over Pd based catalysts for applications for heavy-duty diesel engines, and found that the sample containing vanadium show high activity and wider temperature window. Silver and copper exchanged zeolite show high efficiency for sulfur removal from natural gas. A simple and effective technique was developed to build carbon bridges that serve to improve contact between a spillover source and a secondary receptor, and then increase the capacity of hydrogen storage.