To determine the concentrations of total oils,petroleum hydrocarbons,and animal and vegetable oils in water,the conventional analytical methods involve two scans as well as a step of magnesium silicate adsorption to remove the animal and vegetable oils in water samples.In this study,a novel analytical method was developed to determine the above oils in wastewater samples through just one scan—the concentration of animal and vegetable oils,and that of total oils were determined by measuring the absorbance of the 〉C=O bond in the peak area between 1750 cm and 1735 cm^（-1）,and of the C-H bond at 2930 cm^（-1）,2960 cm,and 3030 cm^（-1）,respectively.The concentration of petroleum hydrocarbons was then calculated by subtracting the concentration of animal and vegetable oils from that of total oils.Compared with the well-known analytical method GB/T 16488-1996,the novel approach displayed similar accuracy in the quantitative determination of oils in wastewater samples,but significantly reduced material cost and operation time.
A series of biodegradable amphoteric chitosan-based flocculants （3-chloro-2-hydroxypropyl trimethyl ammonium chloride （CTA） modified carboxymethyl chitosan, denoted as CMC-CTA） with different substitution degrees of CTA were prepared successfully. The content of carboxymethyl groups in each CMC-CTA sample was kept almost constant. The solubility of the various flocculants showed that, higher cationic content of flocculants caused a better solubility. The flocculation experiments using kaolin suspension as synthetic water at the laboratory scale indicated that the substitution degree of CTA was one of the key factors for the flocculation properties. With the increase of cationic content, the flocculants were demonstrated better flocculation performance and lower dosage requirement. Flocculation kinetics model of particles collisions combining zeta potential and turbidity measurements was employed to investigate the effects of the cationic content of the flocculants on the flocculation properties from the viewpoint of flocculation mechanism in detail. Furthermore, flocculation performance using raw water from Zhenjiang part of Yangtze River at the pilot scale showed the similar effects to those at the laboratory scale.
An anion exchange resin NDP-5 has been prepared successfully and applied on the selective removal of nitrate from SO_4^（2-）/ NO_3^- binary co-existence system.The composition and morphology of NDP-5 were confirmed by FT-IR and SEM.The NDP-5 resin exhibits the completely different behavior on the adsorption capacity,adsorption kinetic and the effect of the completing anion in the absence or presence of sulfate,compared to D213.And,the resultants of kinetic are well fitted by the pseudo-first-order and pseudo-second-order models.These results are very important to develop novel resins with great features.
Magnetic powder resin Q150 with high specific surface area of 1074 m2/g was prepared by the membrane emulsificationsuspension polymerization technique. Adsoption of tetracycline on the obtained sorbent Q150 was evaluted by using the granule resin （GR） XAD-4, the powder activated carbon （PAC） 1240AC and the granule activated carbon （GAC） HD4000 for comparison. It was found that Q150 had a larger adsorption capacity, faster kinetic and easier regeneration under alkaline condition. The results suggested that the powder resin （PR） Q150 would be a promising sorbent for removing antibiotics and even other organic micropollutants from the aquatic environment.
Qing ZhouI Man Cheng Zhang Chen Dong Shuang Zhe Qin Li Ai Min Li
