Phosphorus Removal Characteristics of Titanium Salts Compared with Aluminum Salt

Abstract

This study evaluates the efficacy of titanium tetrachloride (TiCl4) and titanium sulfate [Ti(SO4)2] on phosphorus (P) removal in synthetic wastewater compared with aluminum sulfate [Al2(SO4)3]. Jar test experiments were performed at various chemical doses and initial pH (pHi) levels to determine the conditions at which P removal was most efficient. The doses with 99% P removal were 0.31 to 0.34 mM for TiCl4, 0.15 mM for Ti(SO4)2, and 0.19 mM for Al2(SO4)3 as Al at 2 mg P/L, 100 mg CaCO3/L, and pHi = 7.0 to 8.0. The optimum pHi was 7 for TiCl4, 5.5 for Ti(SO4)2, and 7 for Al2(SO4)3. The P-removal efficiencies were Ti(SO4)2 > Al2(SO4)3 > TiCl4 at pHi 5.5, and TiCl4 ≈ Al2(SO4)3 > Ti(SO4)2 at pHi 7 and 8.5. P-removal ability of TiCl4 decreased as alkalinity increased. Quadratic models successfully approximated the response surface for P removal efficiency with simultaneous changes in pHi and chemical concentrations [TiCl4 and Al2(SO4)3].

Preparation and Characterization of Photoactive Anatase TiO2 from Algae Bloomed Surface Water

“…TiCl 4 has been found very efficient in removing phosphorous from wastewater. Jeon et al [42] reported that both Ti and Al-based coagulants perform similarly when the initial pH of the feed water is 7, which is in agreement with the current study. At an alkalinity level of 100 mg CaCO 3 /L, they have reported 99% phosphorous removal using a coagulant dose of 0.02 g Ti/L and 0.01 g Al/L, respectively.…”

“…At an alkalinity level of 100 mg CaCO 3 /L, they have reported 99% phosphorous removal using a coagulant dose of 0.02 g Ti/L and 0.01 g Al/L, respectively. It was reported that an increase in alkalinity of feed water was responsible for the requirement of elevated coagulant doses [42]. Consequently, in the current study, the presence of algae in feed water might have increased the alkalinity, causing an augmented demand of coagulants to remove TP.…”