SiC mesoporous membranes for sulfuric acid decomposition at high temperatures in the iodine-sulfur process

Inorganic microporous materials have shown promise for the fabrication of membranes with chemical stability and resistance to high temperatures. Silicon-carbide (SiC) has been widely studied due to its outstanding mechanical stability under high temperatures and its resistance to corrosion and oxidation. This study is the first to prepare mesoporous SiC membranes for use in sulphuric acid decomposition to achieve thermochemical water splitting in the iodine–sulfur process. Single-gas permeation was carried out to confirm the stability of this mesoporous membrane under exposure to steam and H₂SO₄ vapor. Benefiting from the excellent chemical stability of the α-Al₂O₃ membrane support and the SiC particle layer, the SiC membrane exhibited stable gas permeance without significant degradation under H₂SO₄ vapor treatment at 600 °C. Additionally, with extraction, the membrane reactor exhibited an increased conversion from 25 to 41% for H₂SO₄ decomposition at 600 °C. The high performance combined with outstanding stability under acidic conditions suggests the developed SiC membrane is a promising candidate for H₂SO₄ decomposition in a catalytic membrane reactor.

In the present study, SiC particles derived mesoporous membrane was discovered and applied to membrane reactor for H₂SO₄ decomposition. The reaction equilibrium was moved the to the product side by membrane reactor with extraction at 600 °C.

Organosilica-Based Membranes in Gas and Liquid-Phase Separation

Organosilica membranes are a type of novel materials derived from organoalkoxysilane precursors. These membranes have tunable networks, functional properties and excellent hydrothermal stability that allow them to maintain high levels of separation performance for extend periods of time in either a gas-phase with steam or a liquid-phase under high temperature. These attributes make them outperform pure silica membranes. In this review, types of precursors, preparation method, and synthesis factors for the construction of organosilica membranes are covered. The effects that these factors exert on characteristics and performance of these membranes are also discussed. The incorporation of metals, alkoxysilanes, or other functional materials into organosilica membranes is an effective and simple way to improve their hydrothermal stability and achieve preferable chemical properties. These hybrid organosilica membranes have demonstrated effective performance in gas and liquid-phase separation.

Photo-induced sol–gel synthesis of polymer-supported silsesquioxane membranes

Organically-bridged silsesquioxane membranes are fabricated onto a polymeric nanofiltration membrane via photo-induced sol–gel processing and their molecular separation performance are investigated through pervaporation of azeotropic mixture.