Adsorption studies for the removal of acid red dye from waste streams

The adsorption characteristics for the removal of dye from tannery wastewater streams onto commercial activated carbon in powdered form were studied from UV-visible spectrophotometric measurement. The efficiency of the adsorbent was judged from the variation of the % adsorption with (i) contact time and initial concentration, (ii) adsorbent dose, (iii) pH and (iv) Temperatures. The highest % adsorption was found to be 99.80% at 25 mg/L dye concentration. The optimum dose of adsorbent was 1.5 g/50 mL of 150 mg/L dye at which the adsorption was 90.20 % as maximum. For 100 mg/L of dye concentration, the pH 4.5 was found as optimum at which the adsorption was effective. The optimum temperature was 35°C, at which the removal efficiency was 93.5 % for 150 mg/L of dye concentration and this reaction was taken as exothermic in nature.