A comparative assessment of adsorbents prepared from industrial wastes for the removal of cationic dye

Carbon slurry waste from fertilizer plant and blast furnace slag, dust and sludge from steel plant have been investigated after some processing as adsorbents for the removal of methylene blue dye. The results have indicated that the carbonaceous adsorbent prepared from carbon slurry waste of fertilizer industry has high porosity and much larger surface area (380 m(2)/g) as compared to other three adsorbents (4-28 m(2)/g). This has resulted in large adsorption of the dye (92 mg/g) on this adsorbent whereas the adsorption on the other three adsorbents is poor (2.1-6.4 mg/g). The adsorption of methylene blue on carbonaceous adsorbent conforms to Langmuir model, and is a first order process and pore diffusion controlled. A comparison of its performance with standard activated charcoal sample shows that its efficiency is 45% as compared to standard sample and thus can be used as alternative in view of its low cost.