Journal of Materials Science and Engineering with Advanced TechnologyAuthor's: Addis Lemessa Jembere
Pages: [21] - [42]
Received Date: September 18, 2018; Revised October 5, 2018
Submitted by:
DOI: http://dx.doi.org/10.18642/jmseat_7100122004
Recognizing the fact that rice husk is a potential biomass source of
abundant silica 
this study aimed at synthesizing silica from
burnt rice husk ash. A method based on alkaline extraction followed by
acid precipitation was developed to produce silica xerogels from rice
husk ash. Ten grams of sample of rice husk was taken in the
experiment. The process of extraction involved comprehensive
techniques such as: acid washing, extraction/precipitation,
filtration, centrifugation, ageing and drying. The effect of NaOH
concentration, extraction temperature and extraction time was
investigated. Apart from this, effect of washing and unwashed rice
husk ash on impurity removal was analyzed quantitatively. ICP
(inductively-coupled plasma emission spectrometers) was used to study
the mineral present in the rice husk ash leading to investigate the
degree of impurity removal. Major impurities silica produced were K,
Ca, Na, and Al. Statistical analysis based on ANOVA was used to
determine the maximum possible yield. Regression model was used to
develop an empirical model to correlate the factors. Maximum yield was
noted at temperature of 60ºC, 2.5M of NaOH concentration and 1.5hrs
of extraction time. Surface area and moisture content of the gel
resulted 
and 3.20%, respectively.
rice husk, xerogel, silica gel.
