Arsenic Removal of Filters by Heat Treated Mixtures of Yellow Loess and Sand in One-Dimensional Column for Real Groundwater Treatment

摘要

It is described that the arsenic (As) removal in real groundwater by filters in one-dimensional (1D) column (30 mm diameter x 240 mm height) using mixtures of heat treated yellow loess (YL) and sand is applied with consideration of water permeability. The effluent satisfies the concentration of 10 ppb drinking water regulation before As saturation with filters. Heat treated mixture of YL and sand under 4% H-2/96% Ar condition result in higher As removal capacity than heat treated one under air atmosphere condition at 500 degrees C for 3 hours. It is due to more evolution of Fe3O4 phase in the mixture. In order to increase As removal efficiency significantly, alpha-Fe2O3 coated filters on mixture of YL and sand by hydrothermal treatment at 100 degrees C for 12 hours are utilized. It leads to highly enhanced As removal efficiency with little Fe ions leaching but half reduction of effluent rate, appealing as an alternative of practical As removal filters.