Utilization of fly ash as granular adsorbent material for removal of naphthol dyes

Dyes pollutant in aquatic environments is a serious environmental problem. One of dyes pollutant sources is batik industry which is textile industry developing in Indonesia. Naphthol is widely used in batik industry and can be removed by adsorption process. Fly ash, solid waste from coal combustion, can be used as dyes adsorbent. In this study, fly ash was made into granular fly ash using PVA-CMC-GA binder and utilized as adsorbent for removal of naphthol dyes from batik industry waste water. The effects of pH and time on adsorption process were studied. The results showed that the highest removal efficiency was obtained at pH of 2 and showed relatively constant value after 18 hours. Kinetics studies on naphthol dyes adsorption by granular fly ash were conducted using pseudo-first order, pseudo-second order, Elovich, and intra-particle diffusion models. The adsorption of naphthol dyes by granular fly ash followed Elovich kinetics model.