tailieunhanh - Rice straw cellulose aerogels

In this study, cellulose was obtained from rice straw by dewaxing with Soxhlet extraction and treating with sodium hydroxide and hydrogen peroxide. The obtained cellulose was used to successfully fabricate cellulose aerogels with a binder by freeze drying technique. The materials were then functionalized with methyltrimethoxysilane (MTMS) to achieve hydrophobicity. | Vietnam Journal of Science and Technology 56 (2A) (2018 ) 118-125 RICE STRAW CELLULOSE AEROGELS Huynh Minh Dat1, Tran Du Tuan1, Thai Ba Quoc1, Ho Khanh Duong1, Dang Ngoc Bich Tien1, Tran Quyet Thang2, Le Khac Duyen2, Nguyen Truong Son*,1 1 Department of Chemical Engineering, Ho Chi Minh City University of Technology, VNU-HCM, 268 Ly Thuong Kiet St., Dist. 10, Ho Chi Minh City, Viet Nam 2 Department of Mechanical Engineering, National University of Singapore, 9 Engineering Drive 1, Singapore 117575 * Email: ntson@ Received: 08 April 2018; Accepted for publication: 13 May 2018 ABSTRACT In this study, cellulose was obtained from rice straw by dewaxing with Soxhlet extraction and treating with sodium hydroxide and hydrogen peroxide. The obtained cellulose was used to successfully fabricate cellulose aerogels with a binder by freeze drying technique. The materials were then functionalized with methyltrimethoxysilane (MTMS) to achieve hydrophobicity. The morphology, pore structure and other properties of the aerogels were characterized by scanning electron microscopy (SEM), X-ray powder diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), thermogravimetrical analysis (TGA), thermal conductivity and water contact angle (WCA) measurements. The rice straw cellulose aerogels exhibited very low specific density ( g/cm3), high porosity (> 96 %), superhydrophobicity (WCA > 137o) and low thermal conductivity ( W/()). The aerogels showed good oil adsorption capacity of g/g. Keywords: rice straw, cellulose aerogel, freeze drying, thermal conductivity, oil adsorption. 1. INTRODUCTION In the condition of global warming, thermal insulation in buildings and plants is the major concern which affects manufacturing and human beings. Indeed, a vast amount of insulation materials have been developed with low thermal conductivity ( ) such as polystyrene ( = 30-40 mW m-1 K-1), polyurethane ( = 20-30 mW m-1 K-1), fibre .