Heavy metal removal of chromium from aqueous solutions by tamarind fruit shell activated with sulfuric acid

Environmental contaminated by heavy metals caused many attentions to discharge of sewage. In recent years,several methods of treatment have been developed for treating of wastewater, reducing the volume of produced sludgeand improving water quality. The adsorption is an efficient treatment method due to easy operation and high efficiency.In this study, effectiveness of tamarind fruit shell activated with sulfuric acid 98% (w/v) have been investigated toremove heavy metal of chromium from really wastewater of electroplating process compared with commercial activatedcarbon. The experimental results showed for tamarind fruit shell activated with sulfuric acid, maximum adsorption occurs at pH=1 and the system has reached equilibrium in 2 hours. The pollutant concentration is between 5 to 150(mg/L). The maximum removal rate of 98 % occurs for a concentration of 5 (mg/L). The adsorbent dose was between 1 to 10 (g/L).These tests indicate positive effect of increasing adsorbent dose and adverse effect of increasing initial concentration inremoval percentage. Removal of chromium decreased slightly with increasing pH. Removal rate in optimal conditions was 98% which was much more effective than commercial activated carbon (72.3%). The results are adapted with Langmuir and Freudlich isotherms

Keywords:

Adsorption , Chromium , tamarind fruit shell , heavy metals