Phosphate adsorption capacity of fly ash: A comparative study between synthetic and raw waste water

摘要

Phosphate immobilization in synthetic waste water is done using fly ash which contains 6.78% of ca ions. The maximum dephosphorization capacity of fly ash was calculated to be 0.84 mg per gram of fl By using Freundlich adsorption isotherm, the sorption is considered to be the combined effect of adsoi as well as precipitation or a multilayered adsorption process. When the experiment was done at the condition for raw waste water collected from dairy plant revealed that less amount of phosphatf removedby the same fly ash. Langmuir adsorption isotherm was adopted to calculate the maxi adsorption capacity of the adsorbent. Considering the process to be a monolayer adsorption process maximum phosphate removal capacity for fly ash in case of dairy effluent was found to be 0.312 mg/g to the presence of sulphate, bicarbonate and chloride ions the rate of phosphate precipitation was aff hence the phosphate removal was considered as a purely adsorption process. Two different adsor isotherms were accepted forthe two phosphate solution by comparing the regression constant value.