A systematic study for the characterization of a novel coagulant (polyaluminium silicate chloride)

Effect of OH−/Al3+ and Si/Al molar ratios on the coagulation performance and residual Al speciation during surface water treatment with poly-aluminum-silicate-chloride (PASiC)

“…The hydrolysate of Al appeared mainly in form of dimer, monomer or lower polymerization degree coordination of Al 3+ with hydroxyl [23]. As also stated by others, with increasing OH − /Al 3+ ratio, the polymerization degree of Al in PASiC was improved and the content of larger polymeric Al species also increased [24]. Similarly, Gao et al [13] suggested that the combination of PAC and polysilicic acid could be enhanced in aggregating efficiency due to high molecular weight but weakened charge effect in the coagulation process.…”

“…The polysilicic acid could combine with Al and its hydrolysis product by Al-O-Si bonds to form hydroxyaluminosilicate, which could retard the hydrolysis-polymerization of Al to some extent. The polysilicic acid, a negative polymer due to terminal oxygen atoms, could neutralize positive charge in polyaluminum and also polymerize with Al and its hydrolysis products to form silica-aluminum hydrolyzed species complexes which possibly favored the formation of polymers with larger size and subsequently improved bridge adsorption effect of PASiC [12,24]. The lower Si/Al ratio in PASiC produced higher positively charged but smaller molecular sized product, and higher Si/Al ratio produced lower positively charged but larger molecular sized product.…”

“…The addition of polysilicate in PAC could react with Al and its hydrolysate, and thus decreased the positive charge and increased molecular weight in PASiC coagulant [12,24]. The removal efficiencies of monitored parameters with increasing coagulants dosages for PASiC 10 , PASiC 5 and PASiC 2 (B = 2.00) coagulation were given in Fig.…”

The Melting Reaction Mechanism of NaOH in Decomposing Ca2SiO4

“…We can know that the absorption peak 3426 cm À1 belongs to the stretching vibration peak of O-H of the adsorbed water (Tzoupanos et al 2009), while the absorption peak 1647 cm À1 belongs to the bending vibration peak of O-H of the adsorbed water. The absorption peaks 1076 cm À1 , 984 cm À1 , 953 cm À1 , and 866 cm À1 belong to characteristic peaks of Ca 2 SiO 4 .…”

Potential Use of Polyaluminium Chloride and Tobacco Leaf as Coagulant and Coagulant Aid in Post-Treatment of Landfill Leachate

“…According to Ntampou et al (5), physicochemical treatment are favorable for stabilized leachate. Coagulation-flocculation has been a common technique practiced using a variety of conventional coagulants such as alum, polyaluminium chloride (PAC), and polyaluminium silicate chloride (7)(8)(9)(10)(11)(12). It has been reported that conventional coagulants are efficient in removing 10% -25% of COD from young leachates and 50% -65% of COD from old leachates (13).…”