MEASUREMENT OF NITRATE ADSORPTION CAPACITIES WITH DIFFERENT SOILS – A COLUMN TRACER STUDY

In most mineral pollution episodes, several minerals are released simultaneously into the environment and it is of crucial importance to know the retention of a metal in detriment of another. Due to increased use of pesticides and fertilizers, Nitrates are accumulating into soil and leaching into groundwater thereby contaminating both soil and water. Agriculture, including commercial livestock and poultry farming is the source of many organic and inorganic pollutants in surface waters and groundwater. These contaminants include both sediment from erosion cropland and compounds nitrogen that partly originate in animal wastes and commercial fertilizers. Animal wastes are high in oxygen demanding material, nitrogen and this often harbor pathogenic organisms. Keeping the above points in view a nitrate adsorption study was planned. In the present study a series of soil column tracer experiments were conducted with two different soils, namely black cotton and red soil. From the discussions it can be attributed that the column tracer experiment with black cotton soil takes less time to reach equilibrium than red soil. Similarly from the both Langmuir and Freundlich isotherms it is evident that the retardation factor is affected by the percentage fines available in soil. If the percentage fines of the soil are more than the adsorption capacity will be more. Finally black cotton soil shows good removal efficiency and hence it can be used as adsorbents. Keywords— Nitrate (No3-) adsorption, sorption, isotherm, retardation factor, column tracer experiment