Degradation of anthraquinone dye C.I. Reactive Blue 19 in aqueous solution by ozonation

This study investigated the degradation of anthraquinone reactive dye C.I. Reactive Blue 19 (RB-19) with initial concentration of 100 mg L⁻¹ in aqueous solution by ozone oxidation. The results of UV/VIS and FTIR spectra showed that the anthraquinone structures, nitrogen linkages and amino groups of RB-19 were destroyed under direct ozone reaction. The identification by LC–MS and GC–MS analyses indicated that some organic acids (e.g., phthalic acids) and 1,3-indanone could be the primary degradation products, respectively. The Microtox toxicity of the ozonated RB-19 solution initially increased but subsequently decreased when ozonation time increased. This detoxification accompanied biodegradability enhancement revealed by BOD/COD ratio increasing from 0.15 to 0.33 after 10 min of ozonation.     

3D打印气体扩散电极产H2O2及其对焦化废水的处理研究

利用3D打印技术设计出一种高效产H₂O₂的3D打印气体扩散电极（3D-GDE）并将其应用于电芬顿体系对实际焦化废水降解研究.结果表明3D-GDE阴极H₂O₂产量高达16.1mg H₂O₂/cm²,而相同条件下传统气体扩散电极仅为7.16mg H₂O₂/cm².通过考察不同因素对阴极产H₂O₂影响可知：酸性条件更有利于产H₂O₂;电流从200mA提高到250mA,其H₂O₂产量从250mg/L提高到450mg/L,但是继续提高电流时（250~300mA）,H₂O₂并没有明显增加.将3D-GDE电极应用于电芬顿对实际焦化废水处理,在最适宜条件下,可以实现对焦化废水有效矿化（4h电解后高达80%）,其降解过程中三维荧光指纹分析也直接证明了该体系的高效性.Microtox毒性实验表明,3D-GDE电芬顿体系可以有效的降低焦化废水体系的毒性,其最低能耗为0.9kW·h/g TOC.     

Toxicity tests with luminescent photobacteria and quantitative structure activity relationships for nitroparaffins

EC₅₀ values of different nitroparaffins were determined by a photobacterium phosphoreum toxicity test. Octanol/water partition coefficients were determined by a reversed phase HPLC method. From these experimental data quantitative structure activity relationships were deduced which point to a dependence of toxicity on a “form factor” that includes the number of methyl and methylene groups in a molecule. The hypothesis will be formulated that the specific effects depend on the number of methylgroups and an equation for specific effects is given.     

Toxicity measurements in aqueous solution during ozonation of mono-chlorophenols

The Microtox toxicity and Oxygen Uptake Rate (OUR) inhibition tests were conducted to monitor the variation of toxicity during ozonation of 2-chlorophenol (2-CP), 3-chlorophenol (3-CP) and 4-chlorophenol (4-CP) under neutral conditions. The results revealed that the oxidized 2-CP solution exhibited new toxicity to pure bacteria and mixed microorganisms in the early stage of ozonation. The largest inhibition of OUR appeared at one mol of applied ozone dosage per mol of initial 2-CP, and the percentage of inhibition was 63.8%. In addition, ozonated 3-CP and 4-CP also significantly induced new aqueous toxicity, if these toxic intermediates were not further ozonated. Comparing the variation of toxicity and the hydroxylated/chlorinated intermediates formed, 3-chloro-catechol, 2-chloro-2, 4-hexadienedioic acid and the dimmer compounds may be related to the sources of toxicity during the ozonation of 2-CP.