Siam Physics Congress 2018

Facile synthesis of high purity nano-silica xero-gel from rice straw ash

21 May 2018, 17:45

1h

Ayutthaya Room

Poster Nanoscale Physics and Nanotechnology A05: Nanoscale and Surface (Poster)

Speakers

Mr Sorawich Asapha (Department of Physics, Faculty of Science and Technology, Phetchabun Rajabhat University, 83 M.11 T.Sadiang, Muang, Phetchabun 67000, Thailand)Dr Chalad Yuenyao (Department of Physics, Faculty of Science and Technology, Phetchabun Rajabhat University, 83 M.11 Sadiang sub-district, Muang, Phetchabun 67000, Thailand)

Description

Abstract
High purity nano-silica xerogel was synthesized from rice straw ash that is a residue materials from agriculture. To obtain the rice straw ash for preparing of sodium silicate that is then used as silica source, pretreated rice straw was burned at 600-900 oC. Rice straw ash was reacted with 0.5 M NaOH for 3-12 h and filtrated by a no.41 filter to prepare sodium silicate. Afterwards, sodium silicate was mixed with 0.5 M HCl for 6 h to produce the nano-silica. In this study, nano-silica was synthesized by using a template, as well. Characteristics of nano-silica synthesized with and without template were compared. In order to get the pure nano-silica xerogels, as-synthesized silica was filtrated and clean with deionized water for 3 times, dried in electric oven at 85 oC overnight and calcined at 500 oC. To confirm the quality of particles, nano-silica was characterized by various analytical techniques like SEM, TEM, XRD, FTIR-ATR, BET, % whiteness and measurement of water contact angle. First experimental results showed that nano-silica xerogels with purity up to 99 wt% were completely synthesized by a facile method. Nano-silica with intermediate specific surface area and pore volume was obtained. Experimental results also showed silica-xerogels with good absorption properties.

Keywords: Rice straw ash; Nano-silica; Xerogel; Facile-method; Surface area.