Liping Zhang,Xin Zhang,Jun Xiang,Jingwen Xue,Xuejing Song
Salicylhydroxamic acid is an excellent collector of oxidizing ore, and it has an efficient collection performance for tungsten molybdenum ore. However, the utilization ratio of salicylhydroxamic acid is relatively low in the flotation process, and a large amount of flotation wastewater discharged might cause damage to the water environment. This study mainly compared the effects of natural sunlight degradation, ozonation, and Fenton oxidation processes on the treatment of salicylchydroxamic acid wastewater from W–Mo mineral processing. The results showed after 30 hours degradation by natural sunlight, the CODcr removal rate of wastewater was only 25.99%. When the initial pH was 8, the dosage of O3 was 1.3 mg/L and the reaction time was 60 minutes; O3 oxidation could remove 40.37% CODcr from wastewater, and the BOD5/CODcr value increased to higher than 0.3 after 15 min reaction. Under the Fenton oxidation conditions such as initial pH 3, H2O2 dosage 0.96 g/L, and the molar ratio of H2O2 to Fe2+ 2 : 1, 90.43% CODcr could be removed from flotation wastewater after 90 min reaction, and the BOD5/CODcr value was obviously improved. Fenton oxidation was a high efficient processing technology for salicylhydroxamic acid wastewater, and the effluent could meet the discharge and reuse emission standard requirements in China.
Mingfu Li,Guangxing Li,Yi Liu,Ye Jin,Kelei Zhang,Lianxin Luo
Fenton’s reagent has strong oxidizing properties and can effectively remove refractory organic pollutants. Fenton’s reagent was applied to deal with the dissolved colloidal substance (DCS) in the white water of old corrugated container (OCC). The optimum reaction condition on Fenton treatment was analyzed by response surface methodology (RSM) based on response values of DCS and COD Cr . The result indicated that the optimized condition is as following, pH is 2.45, a mass ratio of H 2 O 2 and COD Cr is 1.1 and a mole ratio of FeSO 4 and H 2 O 2 is 0.35. Under the optimum condition of a single factor experiment, the experimental results showed that the removal rate of CODcr and DCS was 90.68 % and 1.61 g/L respectively, which was consistent with the response surface analysis prediction values. During the Fenton oxidation, the particle sizes of DCS decreased, the ions content and turbidity of the white water decreased, however the electrical conductivity and zeta potential of the white water raised slightly. Gas Chromatography-Mass Spectroscopy (GC-MS) analysis proved that benzoic acid and nonandioic acid can be effectively removed by Fenton’s reagent, however the content of dehydroabietic acid decreased by 24.07 %.
Liheng Liu,Ronghao Yu,Shixiong Zhao,Xingfeng Cao,Xuehong Zhang,Shaoyuan Bai
In this study, the treatment performance of a heterogeneous Fenton system (Fe-BC + H 2 O 2 ) driven by iron-loaded sludge biochar (Fe-BC) on wastewater containing sulfamethoxazole (SMX) was investigated using the CODcr removal efficiency ( φ ) as an indicator. The batch experimental results showed that the optimal operating conditions were as follow: initial pH 3, H 2 O 2 concentration 20 mmol L −1 , Fe-BC dose 1.2 g L −1 , temperature 298 K. The corresponding φ was as high as 83.43%. The removal of CODcr was better described by BMG model and revised BMG (BMGL) model. According to the BMGL model, the φ max could be 98.37% (298 K). Moreover, the removal of CODcr was a diffusion-controlled process, while liquid film diffusion and intraparticle diffusion together determined its removal rate. The removal of CODcr should be a synergistic effect of adsorption and Fenton oxidation (real heterogeneous Fenton and homogeneous Fenton) and other pathways. Their contributions were 42.79%, 54.01% and 3.20%, respectively. For homogeneous Fenton, there seemed to be two simultaneous SMX degradation pathways : SMX→4-(pyrrolidine-11-sulfonyl)-aniline→N-(4-aminobenzenesulfonyl) acetamide/4-amino-N-ethyl benzene sulfonamides→4-amino-N-hydroxy benzene sulfonamides; SMX→N-ethyl-3-amino benzene sulfonamides→4-methanesulfonylaniline. In summary, Fe-BC had potential for practical application as a heterogeneous Fenton catalyst.
危险品化学品经营许可证（带存储）