Fluoride-free and seed-free microwave-assisted hydrothermal synthesis of nanosized high-silica Beta zeolites for effective VOCs adsorption
Zhe Ma, Hua Deng, Lin Li, Qiang Zhang, Guangrui Chen, Chang Sun, Hong He, Jihong Yu
Abstract
or seeds, are highly important in volatile organic compounds (VOCs) adsorption. Fluoride-free or seed-free synthesis of high-silica Beta zeolites attracts great attention. Herein, highly dispersed Beta zeolites with a size of 25-180 nm and Si/Al ratios of 9-∞ were successfully synthesized by a microwave-assisted hydrothermal strategy. We have for the first time revealed that microwave irradiation can induce the formation of hydroxyl free radicals (˙OH), promoting the formation of the Si-O-Si bond. Thanks to the high total surface area, pore volume, and excellent hydrophobicity, the as-prepared pure-silica Beta zeolite presents a higher toluene adsorption capacity in VOCs adsorption compared to other pure-silica Beta zeolites prepared by traditional methods. This work provides a facile avenue for fluoride-free and seed-free synthesis of nanosized high-silica zeolites, promising their important applications in VOCs adsorption.