Evaluación de la eficiencia de la cascarilla de arroz para eliminar cafeína y triclosán de agua residual sintética mediante adsorción

Abstract

The adsorption capacity of the rice husk was evaluated for different particle sizes, to eliminate caffeine and triclosan present in synthetic wastewater, analyzing the influence of dose and contact time. The isotherm and adsorption kinetics were determined and the removal process was adjusted. The material was conditioned maintaining its natural characteristics and ASTM standards were used for the physical-chemical characterization. Morphology was determined by SEM and with

FTIR, functional groups present on the surface were identified. The adsorbent capacity was determined with batch tests, varying the adsorbent dose (1 g/L – 50 g/L) and optimal contact time (5-300 min). The maximum caffeine removal was 96.5% and triclosan 100.0%. The adsorption kinetics were adjusted to the pseudo-second order model and to a Freundlich isotherm for the two cases, with correlation coefficients greater than 0.95. The maximum adsorption capacity for caffeine was 8.77 mg/g and for triclosan 53.76 mg/g. The adsorptive capacity depends on the particle size, the larger there is the less surface area available for adsorption. The availability of the rice husk makes it an economical and easily accessible adsorbent