S Sadri Moghaddam - Civil and Environmental Engineering Department, Amirkabir University of Technology (AUT), Tehran, ۱۵۸۷۵- ۴۴۱۳, Iran
M.R Alavi Moghaddam - Civil and Environmental Engineering Department, Amirkabir University of Technology (AUT), Tehran, ۱۵۸۷۵- ۴۴۱۳, Iran
M Arami - Textile Engineering Department, Amirkabir University of Technology (AUT), Tehran, ۱۵۸۷۵- ۴۴۱۳, Iran

In this research, ferric chloride sludge (FCS) of a water treatment plant was used as an alternative coagulant for removal of acid red 119 dye. For this purpose, the effect of pH, adsorbent (FCS) dose and initial dye concentration on dye removal efficiency were investigated. Results showed that the dye removal rates were largely dependent on the pH. When the solution pH was increased from 3 to 8, the dye removal rates decreased from 96.3% to 2.3%. The removal efficiencies of the dye using 130-350 mg dried FCS/L were more than 90% at pH =3. With the increase of initial dye concentration in the range of 10-200 mg/L, the removal efficiency increased at first (from 10-40 mg/L) and then declined. So, FCS can be considered as an appropriate coagulant for the removal of acid red 119 dye.

Acid Red 119, Coagulation/Flocculation, Dye Removal, Ferric Chloride Sludge (FCS)