Abstract

Synthetic dyes are one of the most important contaminants in textile wastewater, which are often toxic and carcinogenic. This study aimed to determine the efficiency of coagulation and flocculation process using polyferric chloride (PFC) and polytitanium tetrachloride (PTC) in removing Reactive Blue 19 (RB19) anionic dye from aqueous solution. This laboratory-scale study examined coagulant preparation, the effect of pH (3-11), concentration of PFC and PTC coagulants (100-500 mg/L), and initial dye concentration (70-250 mg/L). The results showed that the dye removal efficiency of PFC was 92.37 at an optimum pH of 9, an optimal dose of 350 mg/L, and dye concentration of 150 mg/L. The dye removal efficiency of PTC was 99.83 at an optimum pH of 7, optimal dose of 350 mg/L, and dye concentration of 200 mg/L. The correlation coefficient between coagulant dose (r = 0.91, p = 0.001) and initial dye concentration (r = 0.83, p = 0.01) was significant with dye removal efficiency for PTC. Based on the results, it can be concluded that the PTC with higher removal efficiency, lower coagulant dose, lower effects on solution pH, and higher density of settled sludge has better efficiency to remove RR19 dye from colored wastewater compared to PFC.