【作者】 耿军；

【导师】 魏凤玉；

【作者基本信息】 合肥工业大学 ， 化学工程， 2009， 硕士

【摘要】 二甲胺(DMA)是一种常见的工业原料,在使用过程中会产生大量二甲胺废水,如不加以处理而直接排放,会造成环境的污染以及资源的浪费。针对这一现象,本文分别研究了络合萃取法和离子交换法对DMA废水的处理过程,为实际工业生产中回收利用DMA废水奠定了理论及实验基础。采用络合萃取法处理DMA废水,考察了萃取剂的种类和浓度、稀释剂种类、废水pH值、DMA浓度、油水比等对二甲胺萃取效果的影响;并采用pH值摆动效应对负载有机相进行了反向萃取研究。结果表明,以10 % P204 + 90 %环己烷(体积%)为萃取剂对DMA废水进行络合萃取,二甲胺的去除率可以达到93.0 %;并采用浓度为10 %(体积%)的盐酸水溶液使萃取剂得到再生,二甲胺回收率可达93.8 %;P204萃取DMA是放热反应,?H为?6.50 kJ/mol;采用双对数坐标法推测了萃合物组成为P204与DMA以1:1形式络合;P204负载DMA的红外谱图表明,P204络合萃取二甲胺同时存在离子缔合成盐机制和氢键缔合机制。本文还采用离子交换法处理DMA废水,对DMA废水的流速、浓度、温度及树脂的高径比等因素进行了优化,并研究了洗脱剂的种类、浓度、流速对洗脱效果的影响。实验结果表明,001×7强酸型阳离子交换树脂对DMA废水具有较好的处理效果;当废水以10.2 mm/min的流速通过高径比为3.76的树脂柱,DMA去除率超过99 %,树脂的饱和吸附量高达103.27 mg/g;树脂通过4 % H2SO4以5.1 mm/min的流速洗脱后可重复利用,DMA洗脱率接近100 %。001×7树脂对DMA的吸附过程符合Langmuir模型;离子吸附过程为自发的、吸热的化学吸附过程,其热力学常数为:?G<0,?H>0,?S>0,Ea=6.418 kJ/mol。动力学研究表明,吸附过程为拟二级反应,颗粒扩散过程为主要速率控制步骤。吸附DMA前后树脂的红外谱图表明,001×7树脂与二甲胺分子之间存在着较强的离子缔合成盐机制。更多还原

【Abstract】 As one of the most common chemical raw materials, Dimethylamine (DMA) is widely used in the various industries. It produced large quantities of DMA wastewater during the use and production process of DMA. The DMA wastewater would not be allowed to drain because it not only po1luted environment but also led to great waste of water resources. Aimed at this case, the complex extraction and the ion exchange technology had been used to recover DMA from the DMA wastewater in this paper. It will be beneficial to the recycling of DMA.A complex extraction method was used for the treatment of DMA wastewater. The effects of sorts and concentrations of diluents, sorts of complexing agent, pH of aqueous solution and the volume ratio of oil to water on the extraction of DMA from wastewater have been systematically studied. According to pH-swing effects anti-extraction of loaded organic phase has been researched. The results showed that extraction effiency of DMA in wastewater reached 93.0 % with 10 % P204 + 90 % hexahydrobenzene (V/V), and complexing agents were regenerated with aqueous solutions of 10 % HCl (V/V), the recovery rate of DMA was achieved 93.8 % . The extraction of DMA by P204 is an exothermal reaction with ?H of ?6.50 kJ/mol. By means of double-logarithmic coordinates, the composition of extracted species was deduced, P204:DMA as 1:1. The mechanism of complexation reaction was investigated by infrared spectra of loaded organic phase,there are hydrogenbond- association and ion-association reaction.An ion-exchange method was also adoped to treat DMA wastewater. The imfluence of the flow rate, concentration, temperature, the rate of height to diameter of resin bed on the removal of DMA from wastewater have been systematically studied. Then the effects of sorts, concentration and flow rate of eluants on the elution of DMA were also investigated in this paper. It was revealed that the DMA wastewater would be treated effectively by the strong-base cationic ion-exchange resin 001×7; the equilibrium adsorption capacity of the DMA onto 001×7 would up to 103.27 mg/g, the removal rate of DMA in wastewater exceeded 99 % at DMA flow rate of 10.2 mm/min and the rate of height to diameter 3.76; then resins would be regenerated with 4 % H2SO4 at flow rate of 5.1 mm/min, the recovery rate of DMA was achieved 100 %. The adsorption equilibrium data of DMA onto 001×7 accorded with the Langmuir isotherm. The thermodynamic parameters calculated from the Van’t Hoff plots were: ?G<0, ?H>0, ?S>0, which indicated that the sorption process would be spontaneous and exothermic, purely chemisorption governed; Ea of 6.418 kJ/mol indicated that the adsorption occured more easily in nature. Kinetic studies suggested that the adsorption followed a pseudo-second-order chemical reaction, and the intraparticle diffusion was the main rate-limiting. The FT-IR of the 001×7 resin before and after DMA sorption suggested that the adsorption process of DMA on the 001×7 resin was ion-association reaction.更多还原