Adsorption Of Dye From Aqueous Solution Onto Original And Modified Pumice

Abstract

The objective of this study; (i) to investigate the dye adsorption from aqueous solution by using original pumice as an alternative low cost adsorbent, (ii) to observe the modification effect of original pumice on adsorption capacity, (iii) to determine kinetic and isotherm model constants of original and modified pumice. Dorasyn Red C2B synthetic dye was obtained from Ipliksan Company, Isparta, Turkey. FT-IR analyzes were carried out to determine the effect of pH on adsorbents, modifying pumice with a cationic surfactant to pumice surface and the active adsorptive groups. Effect of pH, contact time, adsorbent dose, and temperature, dye concentration on dye adsorption by original and modified pumice was determined. The results showed that optimum pH value was 1.7, contact time was 60 minutes, and optimum adsorbent dose was 0.15 g for both two samples. The increasing value of temperature decreased the adsorption capacity of each adsorbent. Adsorption capacity of modified-pumice was found to be 28.9 mg/g at optimum conditions. Kinetic studies were carried out to determine the effect of initial dye concentration and initial temperature on adsorption kinetic. Obtained data estimated by Non-lineer Regression Analysis and applied Pseudo I. order and Pseudo II. Order kinetic models. Kinetic studies showed that Pseudo II. order kinetic model well fitted than Pseudo I. order kinetic model to the adsorbent samples. Dye concentration is ranged between 5, 25, 50, 100 mg/L and it was observed that adsorbent samples achieved the maximum adsorption capacity at 100 mg/L dye concentration. Increasing dye concentration increased the adsorption capacity of two adsorbent samples. It was observed that adsorption of dye on original and modified pumice samples decreased with increasing temperature from 10 to 50 ^◦C. The results of isotherm studies emphasizes that the dye adsorption onto modified pumice sample was in a good agreement with Freundlich isotherm model while original pumice did not well fit to the two isotherm models. Pumice can use be modified as low cost and effective adsorbent for dye removal.