Biosorption of manganese in drinking water by isolated bacteria

Water is an important nutrition for living thing, such as humans, animals and plants. Nowdays, it has been polluted with inorganic contaminants which are discharged from industries. Manganese is one of the inorganics contaminant that causes low hemoglobin level, neurotoxicity, pipes clogging and bad taste if the concentrations in water exceed the regulated limit. A biological treatment process was investigated to treat the manganese through the biosorption mechanism by using Biological Aerated Filter (BAF) system. The microbes were taken from sewage activated sludge and isolated in agar media and identified by using Biolog Microstation System. These microbes included both Gram positive and Gram negative groups and the morphology were rod shape (Bacillus). The screening test has been done to select the highest manganese uptake by these strains and further studies under laboratory condition as a function of pH, biosorbent dosages and manganese toxicities were investigated comparison with biosorbent of sewage activated sludge. The biosorption isotherms were fitted with Langmuir to represent the equilibrium of the maximum manganese uptake by bacteria. The screening resulted that HAH1 has a higher manganese uptake capacity than others strain with 13.31 mg Mn2+/g biomass at pH 6 and biomass dosage of 0.1 g. The further studies resulted, manganese biosorption increased with rise in pH, biosorbent dosages and manganese toxicities. The Langmuir isotherm model revealed HAH1 was a better biosorbent of manganese than sewage activated sludge with the maximum biosorption capacity (qmax) of 55.56 mg Mn2+/g biomass and Kd value of 133.44. © Asian Network for Scientific Information.