The novel triolein-embedded composite sorbents for removing persistent organic pollutants (POPs) in water were developed. Comprehensive structural characteristics of the composite sorbents were characterized using scanning electron microscope (SEM), fourier transform infrared spectrum (FT-IR) and X-ray photoelectron spectrum (XPS). It is suggested that triolein/cellulose acetate (CA) viscous syrup can be deposited on the surface of silica gel granules, because the silica gel granules have the large enough aperture to make the polymer penetrate into. Triolein is also embedded into a hybrid membrane perfectly. Dieldrin is regarded as a representative compound of POPs. Sorption experiments in solutions with constant concentrations show that adsorption capacity increased with increased triolein content in composite adorbents. Dieldrin removal could reach 80% at 50 ng/l initial concentration, which is near the environmental level.

The new chemical method for identifying and quantifying Sudan I ( 1-[(2,4-dimethylphenyl)azo]-2-naphthalenol ) from chilli species is devised to overcome the shortcoming with complex operation, longer analytical period of High performance liquid chromatography (HPLC) assay. Sudan I complexed with Cu 2+ leads to the shift of visible absorption wavelength from 478 nm to 526 nm. The major product is the Sudan I complex with general formula [Cu(Sudan I)]Cl. Bonds formed between Cu 2+ and nitrogen, oxygen lead to a larger conjugated system, which accounts for the bathochromic shift. The effect of several factors is investigated. The optimum amount of NaOH (0.1 mol·l -1 ) is 0.2 ml, and the appropriate reaction temperature is kept at 50℃. For the calibration of [Cu(Sudan I)]Cl, the limits of detection (3σ/m) is 0.446 mg·l -1 and apparent molar absorptivity is about 1.094×10 4 l·mol -1 cm -1 . The recoveries (spiked in hot chilli pepper at the levels of 5 mg·kg −1 ) range from 94% to 105%.

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Different metal (Bi, Ni, La, Ce and Er) doped PbO 2 electrodes were successfully prepared by electro-deposition method, and their electrocatalytic degradation capacity for 2, 4-dichlorphenol (2, 4-DCP) in water was compared in a batch experiment. The electrodes were characterized by scanning electron microscope (SEM). The morphology and component analysis showed that metal (Bi, Ni, La, Ce and Er) was scattered between PbO 2 crystals and thus enlarged the effective area and decreased the internal stress in the PbO 2 film, which was beneficial to 2, 4-DCP degradation. 2,4-DCP degradation using different metal (Bi, Ni, La, Ce and Er) doped PbO 2 electrodes as anode was in good agreement with the pseudo-first-order model. After 60 min electrolysis, the removal rate for 2,4-DCP and COD on Er-PbO 2 electrode was 92.9% after 60 min and 65.8% after 360 min, respectively, and the voltage and its change amount is relatively lower, indicating that Er-PbO 2 electrode exhibited higher capacity for 2,4-DCP degradation and better stability (the constant current density: 5mA/cm 2 ; the initial concentration of 2, 4-DCP is 94.1 mg/L; Volume: 100mL).

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