Characterisation of the rice production waste for the use in pharmaceutical industry

In this work we provide the technological parameters for obtaining silicon dioxide from rice husk for its possible use at the pharmaceutical industry. We also show the results obtained in the chemical and physical analysis. The Cuban rice variety (M-10) was characterised and the results were compared with similar data from the literature. Preliminary tests conducted to 23 full factorial design, taking as dependents variables the loss percentage, the silicon dioxide percentage and the sample coloration. The independents variables were the concentration of hydrochloric acid, the temperature and the calcination time. Optimal conditions included washing of the rice husk with hydrochloric acid 1M and calcination at 700 °C during 1 hour. The results derived from the chemical and physical characterisation were within the established range. This work allows the use of an industrial residue, reducing the environmental pollution caused by the accumulation of solid waste.