液膜分离H酸废水三级萃取工艺的优化研究

采用三级逆流萃取工艺,研究了乳状液膜处理H酸废水时Span-80:异辛醇比值、油内比Roi、乳水比Rew、外相pH等因素对废水COD去除率指标的影响.结果表明:Span-80:异辛醇=11(g∶ml),油内比Roi=1∶1.5,乳水比Rew=1∶1,外相废水pH=2.0时,COD去除率达到85.3%.     

用TOA为流动载体的乳状液膜提取对氨基苯磺酸

研究了以三辛胺(TOA)为流动载体的乳状液膜法提取对氨基苯磺酸(PASA)的最优膜配方及工艺条件.结果表明:以3%聚胺型表面活性剂(质量分数),4%TOA(体积分数),10%NaOH(质量分数),油内比Roi为2∶1的乳状液膜体系,处理初始浓度为5 000 mg/LPASA废水,在pH值为3,乳水比Rew为1∶5的传质条件下,提取率可达90%以上.     

乳状液膜处理含铜废水试验

乳状液膜分离技术是治理矿山含铜酸性废水的有效方法,对乳状液膜处理比、不同载体浓度对提取Cu~(2+)的影响进行论述,并分析乳状液膜处理矿山酸性废水的试验结果。     

乳状液膜法处理含铬废水的研究

采用以磷酸三丁酯(TBP)为载体、T152为表面活性剂、磺化煤油为膜溶剂、液体石蜡为膜增强剂、NaOH为内相试剂的乳状液膜体系提取分离废水中的铬(Ⅵ).在探明料液pH值、内水相NaOH浓度、T152浓度、载体用量以及乳水比和油内比对提取效率影响的基础上,确立了最适分离条件.结果表明,含铬(Ⅵ)废水经处理后,去除率达99%以上,铬(Ⅵ)残留量＜0.5mg/L,能达到排放标准.     

液膜处理过程中粘度的变化

研究了影响多重乳状液粘度的一些因素,如表面活性剂、添加剂、油内比、搅拌速度、内相试剂及其浓度、温度等。并对多重乳状液的粘度和溶胀规律作了考察,发现乳状液的粘度与液膜的稳定性和溶胀密切相关。     

液膜处理过程中粘度的变化

研究了影响多重乳状液粘度的一些因素,如表面活性剂、添加剂、油内比、搅拌速度、内相试剂及其浓度、温度等。并对多重乳状液的粘度和溶胀规律作了考察,发现乳状液的粘度与液膜的稳定性和溶胀密切相关。     

油内比和表面活性剂浓度对（稀型）乳状液膜工业过程的影响

在当前破乳技术的基础上,用稀型乳状液膜法治理粘胶纤维工业酸性含锌废水、选择稀型乳状液的油内比Ｒｏｉ大于３,表面活性剂Ｔ１５４的体积分数降至０．６％的条件,在工业上实现了含锌废水的处理,这过程既无二次污染,又 收锌资源,具有一定的经济效益。     

混合型乳化液膜对焦化废水中氨氮的处理

研究了Span-80、Tween-80和四氯化碳为主要原料制备的乳化液膜处理焦化废水,与以Span-80为单一表面活性剂制备的乳化液膜处理焦化废水进行比较.考察了乳化剂的类型、亲水-亲油平衡值、乳化剂用量、硫酸浓度等各种影响因素对氨氮去除率的影响,得出最佳条件:亲水-亲油平衡值(HLB)为5.19,乳化剂用量为0.8g,内相硫酸浓度为0.25mol/L,乳化液膜对于焦化废水中氨氮的去除率可达99.9%.同时,通过两种乳化液膜对焦化废水处理的比较说明,混合型乳化液膜对氨氮去除率要比单一型更好.     

液膜法去除废水中的氨氮污染

研究了用乳状液膜法去除废水中的氨氮污染．选择了液膜体系，考察了各种因素对氨氮去除率的影响．结果表明，由表面活性剂、民用煤油及膜增强剂组成的膜相，稀硫酸的质量分数１０％的内相组成的液膜体系，当乳水比ＲｅＷ＝１∶１０、接触时间为８分钟时，可使氨氮含量在１０００ｍｇ／Ｌ以上的废水，一级去除率达９７％以上，处理后的废水符合排放标准     

乳化液膜的制备及其在1-萘酚废水处理中的实验研究

在较低的转速下(720 r/min),将磁力搅拌和超声方法结合,制备煤油-Span80-NaOH乳化液膜,在较温和条件下制备了稳定性较高的乳化液膜.将制备的乳化液膜应用于1-萘酚废水溶液的处理.系统考察了液膜制备过程的影响因素,如NaOH浓度、超声时间、油内比等;废水处理的操作条件:外水相pH、接触时间和乳水体积比等因素对1-萘酚的去除效果.结果表明,NaOH浓度为2％、超声时间为5 min、油内比为1∶2、无需调节pH、接触时间为15min、乳水比为1∶5时,1-萘酚去除率可高达94％.     

Extraction of phenol by sulfuric acid salts of trioctylamine

Abstract

The extraction of phenol from an aqueous solution using sulfuric acid salts of trioctylamine (TOA salts) was carried out. Trioctylamine (TOA) dissolved in diisopropyl ether (DIPE) (or 1‐octanol, cyclohex‐ane, benzene and kerosene) was evaluated for extraction of phenol at various volume ratios of organic phase to aqueous phase at varied temperatures. The equilibrium distribution coefficient (K_D ) for the extraction of phenol with TOA salts in those diluents was measured. Phenol is extracted by a physical distribution with pure diluent alone and through the interaction between TOA and phenol. The latter was quantitatively interpreted according to a reaction scheme in which adducts of several kinds were composed of trioctylamine and phenol. The TOA salts have a significantly greater extraction capability for phenol than TOA itself. The reaction of phenol and hydroxide ion to form phenoxide ion is used to explain the small extraction of solute at high pH. A simple mathematical model was derived to account for the effect of the volume ratio of organic phase to aqueous phase on the value of K_D, and for the effect of the initial concentration of phenol on the value of K_D.     

Synthesis of Fe3O4 nanoparticles with tunable and uniform size through simple thermal decomposition

A novel and facile method with low cost has been developed to fabricate Fe3O4 nanoparticles (NPs) with tunable and uniform sizes by the thermal decomposition of iron oleate complex. The synthesis of iron oleate complex was carried out using a reaction between oleic acid and FeCl3 x 6H2O at low temperature. The decomposition of iron oleate complex occurs when the complex added in the solution of octadecene (ODE) and trioctylamine (TOA) with simple heat treatment. The X-ray diffraction pattern of a resulting sample indicated that Fe3O4 NPs formed during the decomposition of iron oleate complex. Preparation conditions including reaction time and temperature, the concentration of the complex, and the ratio of TOA and ODE strikingly affected the size and size distribution of resulting Fe3O4 NPs. Under optimal preparation conditions, the size of Fe3O4 NPs was adjusted (less than 20 nm in average diameter). The analysis of samples by a Fourier transform infrared spectroscopy confirmed the formation of iron oleate complex. Because the Fe3O4 NPs revealed a superparamagnetic property as well as tunable and uniform sizes, the NPs will be utilizable for further applications. This simple strategy with low cost has to give a useful enlightenment for the design and fabrication of magnetic oxide.     

Separation of trace level hafnium from tungsten: a step toward solving an astronomical puzzle

182Hf (T(1/2) = 9 x 10(6) y) is believed to be formed by pure r-process during a supernova explosion, and therefore, the search for minute traces of 182Hf in the earth's crust is of great interest. Only accelerator mass spectrometry (AMS) is well suited for detecting such low levels of 182Hf. But any attempt to measure 182Hf by AMS must ensure that the sample is free from its naturally occurring stable isobar 182W. A simple method for separation of tungsten and hafnium has been developed using radiometric simulation followed by checking the decontamination of tungsten from Hf in a synthetic sample by AMS. The separation studies were performed by a liquid-liquid extraction technique using tri-n-octylamine (TOA) as the organic reagent. It has been found that a very high separation factor (1.6 x 10(6)) can be achieved when 0.3 M TOA diluted in cyclohexane is used as the organic phase and 6 M HCl (in the presence of small amount of H2O2) is used as the aqueous phase.     

支撑液膜法提取柠檬酸——膜配方的研究

采用了支撑液膜法从柠檬酸的发酵液中提取柠檬酸,考察了膜的装配方法和载体浓度对传递通量及体系稳定性的影响,在该体系和一定的操作条件下,确定了合适的支撑液膜体系为聚丙烯微孔膜为支撑体,煤油为溶剂,TOA为载体,用湿法装配.     

Effects of compound curing agent on the thermo-mechanical properties and structure of epoxy asphalt

Epoxy asphalt curing system was prepared by sebacic acid compound with methyl-tetrahydrophthalic anhydride (MeTHPA) or Tung oil anhydride (TOA). Tensile strength, penetration, differential scanning calorimetry, dynamic mechanical thermal analysis, torn section microscopy photographs and scanning electron microscope analysis were utilised to investigate the mechanical properties, thermodynamic behaviour and micro-structure of epoxy asphalt curing systems under different curing agents. The results showed that in the presence of compound curing agent, the tensile strength and surface hardness of the epoxy asphalt curing system effectively improved, the induction period of the curing reaction decreased, the curing reaction mechanism turned to one-step reaction from two-step reaction, the Tg of asphalt phase and epoxy phase could simultaneously increase, and high-temperature damping performance also improved, but the particle size of asphalt dispersed in epoxy resin becomes uneven, while the curing system becomes semi-brittle from toughness. Compared to TOA, the effects of MeTHPA on such performance were more obvious.     

Evolution structurale par substitution cationique dans les perovskites hexagonales fluorees: II - Les systèmes Cs1−xRbxMF3 (M = Mg,Co, Ni,Zn)

The substitution of rubidium for cesium in CsMF₃ phases has the same influence as pressure. While no phase transformation is observed if M is magnesium or zinc, the sequences 2H → 9R → 6H and 9R → 6H → 3C are respectively observed in the case of nickel and cobalt with increasing rubidium concentration. The 9R-Cs_0.70 Rb_0.30 NiF₃ phase is antiferromagnetic and the 6H-Cs_0.50 Rb_0.50 CoF₃ compound is a ferrimagnet (T_C = 62 K).     

Selection of design parameters and optimization of operating parameters of soybean oil-based bulk liquid membrane for Cu(II) removal and recovery from aqueous solutions

The objectives of this work were to select suitable design parameters and optimize the operating parameters of a soybean oil-based bulk liquid membrane (BLM) for Cu(II) removal and recovery from aqueous solutions. The soybean oil-based BLM consists of an aqueous feed phase (Cu(II) source), an organic membrane phase (soybean oil (diluent), di-2-ethylhexylphosphoric acid (D2EHPA) (carrier) and tributylphosphate (phase modifier)) and an aqueous stripping phase (sulfuric acid solution (H(2)SO(4))). Effects of design parameters (stirring condition and stripping/membrane to feed/membrane interface area ratio) of soybean oil-based BLM on the Cu(II) removal and recovery from aqueous solutions were investigated and the suitable parameters were selected for further studies. Optimization of the operating parameters (D2EHPA concentration, H(2)SO(4) concentration, stirring speed, temperature and operating time) of soybean oil-based BLM for maximum percentage (%) recovery of Cu(II) was then conducted using Response Surface Methodology and the optimum parameters were determined. A regression model for % recovery was developed and its adequacy was evaluated. The experimental % recovery obtained under the optimum operating conditions was compared with the predicted one and they were found to agree satisfactorily with each other.     

乳状液膜法提取模拟湿法磷酸中的稀土镧

采用自制的磺化聚丁二烯(LYF)作表面活性剂,以二(2-乙基己基磷酸,P204)为萃取剂,以4mol/L HCl为内相,液体石蜡为膜稳定剂,制成乳状液膜,从模拟湿法磷酸中萃取稀土镧.在膜内比为1.2∶1,制乳搅拌,搅拌速度为2 000r/min,时间为20min,提取搅拌速度为250r/min,时间为10min,水乳体积比为2∶1,磷酸质量分数为10%P2O5,La3+含量为300mg/L时,镧离子的迁移率达到86.67%.同时利用液液萃取通过斜率分析法讨论P204从磷酸中提取镧离子的反应机理.对P204萃取镧离子进行热力学研究,结果表明,萃取反应属于放热反应,反应热为-7.697 1kJ/mol.     

Sonochemical degradation of Basic Blue 41 dye assisted by nanoTiO2 and H2O2

The sonolysis of Basic Blue 41 dye in aqueous solution was performed at 35 kHz using ultrasonic power of 160 W and aqueous temperature of 25+1 degrees C within 180 min. The TiO2 nanoparticles were used as a catalyst to assist the sonication process. The effect of experimental parameters such as pH, H2O2 concentration and initial dye concentration on the reaction were investigated. It was recognized that in lower pH values the dye removal rate decreased. However, dye removal increased via increase in H2O2 concentration and lowering the initial dye concentration. All intermediate compounds were detected by integrated gas chromatography-mass spectrometry (GC/MS) and also ion chromatograph (IC). During the decolorization, all nitrogen atoms and aromatic groups of Basic Blue 41 were converted to urea, nitrate, formic acid, acetic acid and oxalic acid, etc. Kinetic studies revealed that the degradation process followed pseudo-first order mechanism with the correlation coefficient (R2) of 0.9918 under experimental conditions. The results showed that power ultrasound can be regarded as an appropriate tool for degradation of azo dyes to non-toxic end products.     

Analysis of the gas phase of cigarette smoke by gas chromatography coupled with UV-diode array detection

A gas chromatography method, coupled with diode array photometric spectral detection in the ultraviolet region (167-330 nm), was developed for the analysis of the gas phase of cigarette smoke. The method enabled us to identify more than 20 volatiles present in the vapor phase of cigarette smoke. In that way, all major volatile organic compounds (including aldehydes, conjugated dienes, ketones, sulfides, furans, and single-ring aromatics), as well as nitric oxide (NO) and hydrogen sulfide (H(2)S), can be analyzed in a straightforward manner through a single chromatographic run of <50-min duration. The method can easily be applied by the introduction of a small volume of the gas-phase stream into the GC injection loop directly through the smoking apparatus exhaust circuit, thus providing an excellent alternative to available methods, which usually require extraction or concentration steps prior to any chromatographic analysis. Furthermore, all problems concerning aging of the gas phase are eliminated. Twelve compounds (including NO) were chosen for quantification through the use of appropriate calibration standards. Comparison of the vapor phase yields of these compounds for the reference cigarette Kentucky 1R4F with already reported data indicates that this method is very reliable as far as accuracy and reproducibility of the results are concerned. Finally, the proposed methodology was used to compare the concentration of these cigarette smoke gas-phase constituents among individual puffs.