COLUMN STUDIES INTO THE ADSORPTION OF CHROMIUM(VI) USING SPHAGNUM MOSS PEAT

Previous batch studies have shown that moss peat is a potentially usef ul biosorbent for treating metal-contaminated wastewaters. This paper examines the use of peat for the continuous adsorption of hexavalent c hromium in columns. Adsorption at two pH values, 2.0 and 2.5, was exam ined and two flow-rates were used at each pH value. The results show t hat both adsorption and reduction occurs in the columns and that the m aximum adsorption capacity of hexavalent chromium (65.87 mg/g) was obt ained at a pH value of 2.0 and a flow-rate of 80 ml/min. However; the higher flow rates also enhanced the reduction reactions in the columns . The data were also tested against the Bed-Depth-Service-Time model a nd it was found that, although the compliance was non-linear, the mode l was appropriate for design purposes.