Stability improvement of zeolite catalysts under hydrothermal conditions for their potential applications in biomass valorization and crude oil upgrading

The future applications of zeolite catalysts could target the valorization of abundant biomass resources and the widely distributed heavy oil deposits. However, a major challenge that can limit this possibility is the low stability of the zeolite systems under the hydrothermal conditions. The paper therefore reviewed classified literature on the different methods being considered for improving the stability properties of zeolite catalysts. Zeolite frameworks modification with fluoride ions, phosphorus, rare metals and silanes provides an opportunity for improving the stability during reactions like cracking, alkylation, isomerization, dehydration etc. All of these reactions are commonly encountered during biomass valorization in hydrothermal media and the heavy oil valorization via catalytic cracking and/or aquathermolysis. The paper thus tailored the progress made and identify the directions for further investigations. (C) 2017 Elsevier Inc. All rights reserved.