【作者】 杨金光；

【导师】 夏清；

【作者基本信息】 天津大学 ， 化学工程， 2008， 硕士

【摘要】 癸二酸是一种重要的有机化工原料,广泛应用于生产聚酰胺工程塑料、耐高温润滑油、耐寒增塑剂、树脂等方面。在目前的工业生产工艺中,每生产1吨癸二酸,需排放约30吨废水,废水中含有的主要成分为硫酸钠、苯酚、癸二酸以及其它一些脂肪酸等。这样的废水直接排放,不仅污染环境,而且也是资源的浪费。因此,本文采用蒸发和吸附相结合的工艺处理废水,以回收其中的硫酸钠作为本文的研究重点,为工业生产提供基础工艺数据。通过实验确定了废水初步处理过程是每1000mL蒸发800mL,浓缩液加硫酸调节为酸性,使pH=2,降温至35℃左右,过滤除去析出的粗癸二酸杂质,得到含硫酸钠的滤液,其COD值约为4800mg/L,溶液颜色发黄,从此滤液可得纯度为98.1%的无水硫酸钠产品,但是产品颜色发黄,有异味,影响质量,所以还要进行后续处理。酸析滤液后续处理比较了Fenton试剂氧化处理、活性炭吸附和NKA-2树脂吸附的效果。采用Fenton氧化法处理酸析滤液,考察反应温度、反应时间、H2O2:FeSO4·7H2O摩尔比和30%H2O2用量对COD去除率的影响,确定最佳操作条件。吸附法考察了静态吸附影响因素:吸附交换时间、温度、溶液pH值和吸附剂用量对COD去除率的影响。通过单因素影响实验,确定了各个影响因素的最佳条件。以活性炭静态吸附处理的效果最好,其最佳条件为:吸附时间:2h;温度:40℃;溶液pH值:2;活性炭用量:10g/150mL酸析滤液。酸析滤液经过活性炭吸附处理以后COD值为830mg/L,COD去除率为83%。从此滤液中可得纯度为99.3%的无水硫酸钠产品,并且所得产品颜色白,无异味,收率为90.0%。动态吸附考察流速的影响,得到低流速有利于动态吸附。利用静态吸附实验测定了平衡浓度和平衡吸附交换量,作出吸附等温线,采用BET模型、Freundlich模型和LangmuirFreundlich模型对等温平衡吸附数据进行拟合,得到了相关模型的参数,其中BET模型最为准确。更多还原

【Abstract】 The sebacic acid is a kind of important organic chemical material which can be widely used to produce the polyamide plastics, high temperature lubricant, cold plasticizer, resin and so on. About 30 tons wastewater will be discharged for each ton production of sebacic acid in the present industrial process. What the wastewater contain are sodium sulphate, phenol, sebacic acid and other fatty acids. The emission of this kind of wastewater not only pollutes the environment, but also loses the valuable resources which are contained in the wastewater. Therefore, evaporation and adsorption processes were used to treat the wastewater in order to recover sodium sulphate in the wastewater. The research result can provide the basic data for the industrial process in the future.Preliminary wastewater treatment process was determined through experiments. After 800 mL water was evaporated from per 1000 mL wastewater, sulfuric acid was added to adjust the pH of the concentrated solution to 2. Then the concentrated solution was cooled to around 35℃, and filtered to remove the precipitates of crude sebacic acid impurities. The filtrate has 4800 mg/L COD and yellow color. The anhydrous sodium sulfhate obtained from this filtrate has purity of 98.1%, but it is not qualified because of its yellow color and odour. Therefore, it is necessary to have further treatment.The results of Fenton reagent oxidation, the activated carbon adsorption and NKA-2 resin adsorption were compared in the follow-up handling of the filtrate. The optimum operating conditions were obtained after detecting the effect of reaction temperature, reaction time, H2O2:FeSO4·7H2O mol ratio and 30%H2O2 consumption on the COD removal in the Fenton oxidation process. In the adsorption experiment, the effect of the adsorption time, temperature, pH and the amount of adsorbent on the COD removal was detected by static adsorption experiment. The optimum static adsorption conditions were determined through single factor experiments. Activated carbon adsoption shows the best result. The optimum conditions are as follows: adsorption time: 2 h; temperature: 40℃; pH value: 2; activated carbon dosage: 10g/150mL filtrate. After activated carbon adsorption treatment, the COD of the filtrate was decreased to 830 mg/L, and the removal rate of COD is 83%. The purity of the anhydrous sodium sulphate recovered from this filtrate can reach 99.3%. The product has no smell, white color, and the yield is 90.0%. In the dynamic adsorption process, the effect of flow rate on the COD removal was studied, the conclusion shows that low flow rate is conducive to dynamic adsorption.The equilibrium concentration and equalibrium adsorption capacity was determined through static adsorption experiments. The models of BET, Freundlich and LangmuirFreundlich are applied to regress parameters of models, and the BET model shows the best result.更多还原