Humidity-conditioning mesoporous molecular sieves synthesized from thin-film-transistor liquid-crystal-display waste glass and SiC sludge

Abstract

This study characterized the humidity conditioning of Al-MCM-41 mesoporous molecular sieves that were recycled from thin-film-transistor liquid-crystal-display (TFT-LCD) waste glass and SiC sludge and synthesized through alkali fusion and hydrothermal processes. Temperatures of 450–650°C, various liquid: solid ratios (5:1, 10:1, 15:1), and different proportions of SiC sludge in the TFT–LCD waste glass were used. The crystal structures of the Al-MCM-41 were determined using X-ray diffraction. The concentrations of heavy metals leached from the materials were below Taiwan's regulatory thresholds. When the liquid: solid ratio was 10:1 and the alkali fusion temperature was 90, 105, or 120°C, the mesoporous molecular sieves met JIS A1470 intensity building materials specifications (moisture adsorption content > 29 g/m2). Mesoporous molecular sieves recycled from TFT-LCD waste glass and SiC sludge had excellent mechanical properties, making them feasible for use in humidity-conditioning applications. This novel synthesis process could also be employed for other Si-related industrial wastes and be beneficial during the large-scale production of valuable silica-based humidity-conditioning materials for environmental protection applications. © 2017 American Institute of Chemical Engineers Environ Prog, 2017