Removal of Nitrate Ion or Nitrite Ion onto Carbonaceous Material Produced from Coffee Grounds by Ion Exchange

Abstract

In this study, carbonaceous material was prepared from coffee grounds as follows: coffee grounds were treated with 1 mol/L calcium chloride solution, and calcined at 600, 800, and 1000oC (CG600, CG800, and CG1000). Subsequently, CGs were treated with 6 mol/L hydrochloric acid solution. Amount of nitrate ion or nitrite ion adsorbed was in the order CG1000 < CG800 < CG600, which indicated that amount adsorbed depended on properties of CG surface (specific surface area and pore volume). The adsorption mechanism of nitrate ion or nitrite ion was ion exchange (1:1) present on the surface of CG600. The adsorption isotherm date were fitted to the Freundlich and Langmuir equations. In binary solution, nitrate ion and nitrite ion were competitive adsorption. CG600 was applied for tap water with a column. Condition 3 (S.V.: 4.3 l/hr, L.V.: 0.4 m/hr) was the most suitable for adsorption of nitrate ion.