[Coagulation performance and mechanism of Al(b) species in treating simulative dye wastewater].

Al(b) species was obtained from polyaluminum chloride (PAC) using ethanol-acetone mixed precipitation method. Al(b) and PAC were comparatively investigated in terms of color removal and zeta potential under different coagulant dosage and solution pH in the treatment of dispersive yellow and direct purple simulative dyeing wastewater. The changes of floc size of Al(b) and PAC were analyzed with PDA2000 and Mastersizer2000, and the coagulation mechanisms were also investigated.

[Coagulation performance and mechanism of Alb species in polyaluminum chloride in removing humic acid].

Alb species [Al12 AlO4 (OH)24(7+)] is multinuclear hydroxyl compound formed in PAC hydrolysis-polymerization process, with properties of small particle sizes, much positive charge, high aggregation degree and large molecular weight. Alb species was purified from PAC containing high concentration of Alb species using ethanol-acetone mixed precipitation method. The influence of dosage, pH and inorganic ions on humic acid removal from simulative water was studied by measuring zeta potential and UV254.

Characterization of floc size, strength and structure in various aluminum coagulants treatment.

Flocs generated in various aluminum coagulants treatment exhibit difference in size, strength and structure. The formation, breakage and re-formation of flocs were investigated by using a laser diffraction instrument (Malvern Mastersizer 2000, Malvern, UK). Different Al coagulants--conventional Al salt (AlCl(3)), polyaluminum chloride (PAC-1) and the purified polyaluminum chloride (PAC-2)--were investigated for the coagulation of humic acid (HA).

Preparation and characteristics of quaternary amino anion exchanger from wheat residue.

Quaternary amino anion exchanger (QE) was prepared from wheat residue (WR) after reaction with epichlorohydrin and triethylamine in the presence of N,N-dimethylformamide and catalyst. The single influential factor experiments and orthogonal tests were carried out in order to obtain the optimal conditions for the preparation of wheat residue quaternary amino anion exchanger (WR-QE). The parameters of the influential factors, which included the types of catalysts, the amounts of WR and triethylamine, and experimental temperatures (activating temperature, catalytic temperature and reacting temperature) were also defined.

[Adsorption kinetics of phosphate from aqueous solutions onto modified corn residue].

The adsorption kinetics of phosphate from aqueous solutions onto modified corn residue was studied in a hatch reactor. The influence of initial pH, concentration and temperature to adsorption effect were investigated. In addition, the kinetic data were fitted by pseudo-first-order equation, pseudo-second-order equation, modified pseudo-first-order equation and intra-particle diffusion model, and the respective characteristic rate constants were presented.