Rice husk is one of the most widely available agricultural wastes. The process of disposal of rice husks looks more crucial as burning the material each year during the winters has been creating a severe environmental challenge. While the husk is often used to meet energy requirements for rice milling, this process produces an enormous amount of ash (approx. 20%) which is a hazardous material to the environment. Researchers at IIT Kharagpur have devised an economic and eco-friendly way to dispose of this biowaste.
A team of researchers from IIT Kharagpur’s Dept. of Agricultural and Food Engineering have developed a chemical treatment which can separate the silica content in the husk ash residue which is about 90 – 95% and neutralize the remaining biomass for disposal in water bodies.
“The silica extracted on purification has the potential of commercial grade silica which can further be used for production of metallurgical and solar grade silicon, confirmed the researchers,” said lead researcher Prof. A K Datta.
Four different alkalis, namely, KOH, K2CO3, NaOH, and Na2CO3, and two different solvents, namely, water and alcohol (ethanol) were selected to accomplish the extraction process. The physical and chemical characterizations of the extracted silica were evaluated using a field-emission scanning electron microscope attached with energy dispersive X-ray spectrometer, X-ray diffractometer, Fourier-transform infrared spectrometer, and atomic absorption spectrophotometer.
To make the process eco-friendly and pollution-free, the rice husk ash was initially dispersed into the water and then Na2CO3 was added to it. As a result, carbonic acid was produced instead of CO2, which is harmless for the environment.
“The results of the study suggested that the morphological, microstructural and compositional characteristics of the extracted silica nanoparticles (SiO2-NPs) are at par with the market available silica” explained Prof. Datta.
The researchers have conducted a cost analysis of the treatment of silica samples to compare the costs with market grade silica. The result of the study suggested that the silica nanoparticle obtained from rice husk ash can be a suitable low cost precursor for Magnesium silicide.
Research Paper Citation:
Nayak, P., Datta, A. Synthesis of SiO2-Nanoparticles from Rice Husk Ash and its Comparison with Commercial Amorphous Silica through Material Characterization. Silicon (2020). https://doi.org/10.1007/s12633-020-00509-y
Contact:
Project: Prof. A K Datta, Dept. of Agricultural and Food Engineering, Email: akd@agfe.iitkgp.ac.in
Media: Shreyoshi Ghosh, Executive Officer (Media & Communication), E: shreyoshi@adm.iitkgp.ac.in
About Dept. of Agricultural and Food Engineering, IIT Kharagpur
The Agricultural and Food Engineering Department is unique of its kind in the IIT system focusing on agricultural research and food and nutritional security. The department comprises six disciplines such as Farm Machinery and Power, Land and Water Resources Engineering, Agricultural Biotechnology, Food Process Engineering, Agricultural Systems Management and Aquacultural Engineering, respectively. The major domain of research and development includes Precision agriculture, biofuel and bioenergy, modern food processing, plasticulture and micro-irrigation, Climate Change, hydrological modeling, groundwater management, water management, agricultural biotechnology, pollution abatement, extrusion technology, intelligent and high pressure packaging, soil mapping and image analysis for plant phenotyping. Research projects include Integrated Rainwater Management, Soil Tillage, Utilisation of Fly ash, Ergonomic Database for Agricultural Equipment, Integrating Remote Sensing Data with Distributed Hydrological Models, Model Pilot Plant and koji room facilities for production of industrial enzymes etc. The department has high-throughput equipment, NABL accredited Analytical Food Testing laboratory, Advanced Laboratories in varied domains. The department has filed several patent applications and transferred many technologies to the industries and various stake-holders based on its innovative research.
Contact Head of the Dept.
Prof. Rintu Banerjee
Phone: +91-3222-282244; Email : head@agfe.iitkgp.ac.in