Jornal de Química Analítica Ambiental

Adsorption of Tartrazine on Medical Activated Charcoal Tablets under Controlled Conditions

Abstract

Mohammed A Kassem and Gamal O El-Sayed

Two types of commercial medical tablets of activated charcoal formulations (AC1 and AC2) were used as adsorbents for tartrazine. The adsorption studies were performed at controlled conditions of pH, and temperature (gastrointestinal-like conditions). It was found that pH plays a major role in the adsorption process. At pH 1.5 and 37°C the effect of different parameters affecting dye removal (salinity, adsorbent dose, initial dye concentration and stirring rate) were examined. The effects of some dietary additives like mono- and disaccharides, artificial sweeteners and glycine on the adsorption efficiency were assayed. The maximum adsorption of tartrazine on activated carbon tablets was observed at highly acidic media. The removal efficiency appears to decrease with increasing temperature and salinity indicating an exothermic process. Equilibrium adsorption isotherms for the removal of tartrazine from aqueous solution using activated charcoal tablets have been investigated. Langmuir and Freundlich’s models were applied to the data related to adsorption isotherms. According to Langmuir’s model data, the observed maximum adsorption capacities (qm) were 272.85 and 456.83 mgg-1 at 37°C for AC1 and AC2, respectively. Medical activated charcoal tablets appear as a very prospective adsorbent for the removal of tartrazine from aqueous solution