THE ABILITY OF ACTIVATED CLAY FOR THE ADSORPTION OF DYES FROM AQUEOUS-SOLUTIONS

A low-cost inorganic acid-activated clay was used adsorbent for the ad sorption of six dyes (two basic, one acidic, one disperse, one direct dye, and one reactive) from aqueous solutions. The adsorption capacity was comparatively high for basic dyes and was lower for disperse, dir ect, and reactive dyes. The equilibrium data could be well described b y the Langmuir equation over the entire range of concentration (50-500 mg dm(-3)). In addition, the effect of temperature on the adsorption was examined and the thermodynamic data were determined. Based on the adsorption capacity only, it was generally shown that activated day wa s more effective compared to ether commonly used adsorbents.