Efficacy of sorption materials for nickel, iron and manganese removal from water

Abstract

Some uncommon elements can sometimes be present in groundwater and surface water. Metals belong to such elements. Increased concentrations of iron and manganese can be expected in groundwater but higher concentrations of metals such as nickel or arsenic are not typical of such water. Nevertheless, water sources exceeding prescribed limits for drinking water in arsenic and nickel concentrations can also be found. Because of the toxicity of these metals, we started to make a research into the possibilities of removing these elements from water. Our research is funded by a grant from the Brno University of Technology. There is a number of ways to remove heavy metals from water. Sorption on granular media based on iron oxides and hydroxides is currently the most used option. Our experiment was carried out using sorption materials GEH, CFH 0818, CFH 12 and Bayoxide, which are primarily designed to remove arsenic from water. We prepared four columns of an inner diameter of 4.4 cm for the purpose of the experiment. The thickness of the filtration media was 0.62 cm on average. Nickel, iron and manganese pollution was simulated in a laboratory. The efficacy of metals removal by four selected sorption materials was compared. During the experiment, the flow rate was set to reach the required retention time of 2.5, 7 and 15 minutes. We have found out that the nickel concentration was reduced according to Regulation No. 252/2004 setting the limit value even after the shortest retention time (2.5 mins). Longer retention time had no significant effect on nickel removal. Our measurements also proved that all sorption materials have the ability to remove iron and manganese from water. Bayoxide sorption material achieved the best results in nickel, iron and manganese removal from water.

Some uncommon elements can sometimes be present in groundwater and surface water. Metals belong to such elements. Increased concentrations of iron and manganese can be expected in groundwater but higher concentrations of metals such as nickel or arsenic are not typical of such water. Nevertheless, water sources exceeding prescribed limits for drinking water in arsenic and nickel concentrations can also be found. Because of the toxicity of these metals, we started to make a research into the possibilities of removing these elements from water. Our research is funded by a grant from the Brno University of Technology. There is a number of ways to remove heavy metals from water. Sorption on granular media based on iron oxides and hydroxides is currently the most used option. Our experiment was carried out using sorption materials GEH, CFH 0818, CFH 12 and Bayoxide, which are primarily designed to remove arsenic from water. We prepared four columns of an inner diameter of 4.4 cm for the purpose of the experiment. The thickness of the filtration media was 0.62 cm on average. Nickel, iron and manganese pollution was simulated in a laboratory. The efficacy of metals removal by four selected sorption materials was compared. During the experiment, the flow rate was set to reach the required retention time of 2.5, 7 and 15 minutes. We have found out that the nickel concentration was reduced according to Regulation No. 252/2004 setting the limit value even after the shortest retention time (2.5 mins). Longer retention time had no significant effect on nickel removal. Our measurements also proved that all sorption materials have the ability to remove iron and manganese from water. Bayoxide sorption material achieved the best results in nickel, iron and manganese removal from water.