Hexavalent Chromium Removal by Litchi chinensis Sonn Peel

Problem statement: We studied the Chromium (VI) removal capacity in aqueous solution by the litchi peel. Approach: We use the diphenylcarbazide method to evaluate the metal concentration. Results: The highest biosorption of the metal (50 mg L^-1) occurs within 6 min, at pH of 1 and 28°C. According to temperature, the highest removal was observed at 40 and 50°C, in 45 min, when the metal (1 g L^-1) was completely adsorbed. At the analyzed concentrations of Cr (VI), litchi peel, showed excellent removal capacity, besides it removes efficiently the metal in situ (100% removal, 5 days of incubation, 5 and 10 g of biomass). After 1 h of incubation the studied biomass reduces 1.0 g of Cr (VI) with the simultaneous production of Cr (III). Conclusion: The shell can be used to eliminate it from industrial wastewater."