Uptake of mercury (II) from wastewater by activated carbon from an unwanted agricultural solid by-product: coirpith Original Research Article

Adsorption studies of mercury (II) from aqueous solutions on coirpith carbon were investigated under the varying conditions of agitation time, metal ion concentration, adsorbent dose and pH. Adsorption equilibrium reached in 10, 25, 30 and 40 min for 10, 20, 30 and 40 mg l−1 Hg(II) concentration. Adsorption followed both Langmuir and Freundlich isotherms. The adsorption capacity was 154 mg g−1. The percent removal increased with the increase of pH from 2 to 5 and remained constant up to pH 11.00. Desorption studies were performed with dilute hydrochloric acid and potassium iodide solutions.