Adsorption of cyanide from aqueous solutions at pyrophyllite surface

The adsorption of cyanide from aqueous solutions at pyrophyllite mineral su rface has been studied by investigating the effect of initial concentration of adsorbate, amount of adsorbent, pH and temperature of test solutions. T he adsorption efficiency is observed to be 99% in dilute solutions but decr eases down to 40%, with increase in cyanide concentration to 10 ppm. The ad sorption is observed to be maximum from neutral solutions and is observed t o increase with increase in temperature. The adsorption data have been fitt ed in Langmuir and Freundlich isotherms and the adsorption has been found t o be endothermic in nature in the temperature range 30-60 degreesC. (C) 200 1 Elsevier Science B.V. All rights reserved.