Coconut Shell Charcoal Combination with Teakwood Sawdust (CSC-TS): An Effective Low-Cost Adsorbent for the Removal Cr (VI) Ion on Industrial Waste Arsy Rachma Zain (a*) Mohammad Masykuri (b)
Department of Chemistry Education, Faculty of Teacher Training and Education, Sebelas Maret University, Jl. Ir. Sutami 36A, 57126 Surakarta, Central Java Indonesia
*arsyyrachmazain[at]gmail.com (a) *mmasykuri[at]yahoo.com (b)
Abstract
The main goals of this study was to develop activated carbon (AC) from coconut shell charcoal (CSC) combination with teakwood sawdust (TS), combination of both on this study was known with (CSC-TS) as a pledging alternative treatment for perilous Cr(VI) metal from industrial waste which investigated with Batch method. Both AC treated differently, coconut shell charcoal prepared with three stages include dehydration with microwave assisted at 373 K for 24 hours, carbonization under 773 K for 1 hour and followed by chemical activation using H3PO4 10% for 24 hours. Meanwhile, teakwood sawdust prepared only with two stages, without carbonization. Batch adsorption process in this study did with the aqueous solutions and applied on batik industrial waste, the functional groups of CSC-TS was characterized using FTIR, furthermore the determination of some parameters in adsorption such as adsorbent dose, effect of contact time, and the effectiveness optimum condition on batik industrial waste obtained by AAS. Several functional groups such as (OH) were detected. Langmuir and Freundlich models were calculated to find out the fit adsorption isotherms where Langmuir models had the greater coefficient correlation value (R2=0,9976) which represented the best isotherm models. The result showed that the Cr(VI) adsorption process was found to be maximum at GT-2,5 with the combination of CSC:TS 1:1,5 and 2,5 g adsorbents dose with 100 minutes of contact time. The percentage removal of Cr(VI) with the initial concentration aqueous solutions 20 ppm under optimal conditions respectively were 87 and 99% with the maximum Langmuir capacity adsorption was 1,08 mg g-1. The initial concentration of batik industrial waste on upstream and downstream were 0,593 and 0,779 mg L-1 with the percentage removal of Cr(VI) were respectively 72 and 83%. This batch adsorption study confirmed that the contaminant of Cr(VI) on industrial waste can be decreased by low cost adsorbent CSC-TS
