Functionalization of mesoporous Al-MCM-41 for indoor humidity control as building humidity conditioning material

Abstract

This study sought to overcome the high energy consumption of mechanical dehumidifiers by synthesizing humidity control materials using alumino-silicate raw materials extracted from stone sludge and cathode ray tube (CRT) waste panel glass. The structure of the synthesized materials matches that of Mobil Composition of Matter No. 41 (MCM-41) mesoporous molecular sieves, which was subjected to amine functionalization using (3-Aminopropyl) triethoxysilane at various concentrations (2.5, 5, 7.5 vol.%). The resulting materials were characterized using X-ray fluorescence analysis, small angle X-ray diffractometry, Fourier transform infrared spectroscopy, transmission electron microscopy, the Brunauer–Emmett–Teller method, and 27Al solid-state nuclear magnetic resonance spectrometry. Al-MCM-41 molecular sieves with 5.0% grafted amine functional groups presented high specific surface area and high pore uniformity resulting in the highest equilibrium moisture content (39.4 kg/kg). The high thermal and humidity buffer capacity of the proposed material could greatly enhance the comfort of interior spaces without the energy consumption of mechanical dehumidifiers.