ADSORBENTES A BASE DE CASCARILLA DE ARROZ EN LA RETENCIóN DE CROMO DE EFLUENTES DE LA INDUSTRIA DE CURTIEMBRES

several adsorbent materials were prepared from rice husk, a lignocellulosic waste from agro-industry, for the removal of chromium present in the effluents of the tanning, due to its high toxicity in the health and to environmental level. the rice husk was evaluated as ash and activated coal with phosphoric acid or hydroxide of sodium as activating agents. the experimental part consisted of calcination of the rice husk, chemical activation, characterization, tests of adsorption and tests of atomic absorption; obtaining better results the adsorbent activated with hydroxide of sodium. the activation of the rice husk with naoh required a series of experiments to determine the best conditions of operation in the process of obtaining of the activated coal. a major removal was obtained in the coal that was activated at 600°c 30 minutes of activation time and 1% p/p of solution concentration; the removal was of the 72,8 % compared with the rice husk ash activated with h3po4 that was of the 54,5% and the rice husk ash 49,2%.