【作者】 张光旭；

【导师】 马沛生； 吴元欣；

【作者基本信息】 天津大学 ， 化学工艺， 2004， 博士

【摘要】 碳酸二苯酯（DPC）是生产聚碳酸酯（PC）的主要原料，所以如何用先进的技术和环境友好的新工艺生产高质量、低成本的碳酸二苯酯已引起世人的关注。氧化羰基化合成DPC不仅流程短，而且是一种绿色工艺，所以该工艺成为国内外研究的热点。但目前国内外大多采用均相催化氧化羰基化合成DPC，由于均相催化存在着催化剂回收、产品后续分离困难等问题，致使该工艺的开发举步为艰。为了克服均相催化存在的问题和为后续开发提供必需的基础数据，本文着眼于非均相氧化羰基化合成DPC并对有关的热力学和动力学进行了研究。具体如下：（1）载体选择及其制备：研究发现以复合氧化La0.62 Pb0.38MnO3为载体，其制备方法为溶胶-凝胶法，焙烧温度为800℃，柠檬酸与金属离子摩尔数的比为1/1，镧的添加量为9.32wt%时，该载体所对应催化剂的性能较好。（2）催化剂的制备：实验表明以NaOH为沉淀剂，用沉淀法负载活性组分Na2PdCl4时，Pd/ La0.62 Pb0.38MnO3催化剂的活性较高。若选取Sn为助活性组分并以混烧法负载、负载量为14.43%时，所得的Pd-Sn催化剂的活性大大提高。（3）工艺条件的优化：通过正交实验得到了最佳的合成工艺条件：P=4.5MPa、θ=60℃、 t=4h、O2含量20％、催化剂与苯酚用量比为1/50。在此工艺条件下，催化剂采用Pd-Sn催化剂时，DPC的收率可达到26.7%，选择性可达到99.5%。就非均相氧化羰基化一步合成DPC而言，本论文所得的DPC的选择性达到文献报道的最高值，而DPC的收率高于文献报道的最高值。 （4）催化剂的失活、再生和改性：通过对催化剂的表征发现原料苯酚过多地沉积及Sn在催化剂表面上的富集而引起活性组分Pd浓度的相对下降，是催化剂失活的主要原因。且当在La0.62 Pb0.38MnO3载体中添加5% Ce时能较好地延长Pd-Sn催化剂的使用寿命。（5）高压气液平衡装置的建立及相关溶解度的测定： 由实验证明该装置不仅能很好地解决苯酚结晶而引起操作不便，而且能大大提高测定数据的速度和可靠性。此外，研究表明除CO2外， CO、O2、N2在苯酚及苯<WP=4>酚－四丁基溴化铵混合溶剂中的溶解度随着温度和压力的升高而增加。当加入四丁基溴化铵后，CO的溶解度略有增加，而O2的溶解度有所下降；采用RK方程和正规溶液理论对气体在纯苯酚中的溶解度进行了关联，并得到了能比较准确地计算溶解度的模型。（6）反应动力学的研究：非均相氧化羰基氧化法一步合成碳酸二苯酯的宏观反应动力学方程式为：323K～343K： 347K～353K： 。更多还原

【Abstract】 Diphenyl Carbonate(DPC)，which is a chemical material mainly used to produce Poly-Carbonate in polyester industry, has been of great interest to prepare DPC with safer process and lower cost. In recent years, a direct oxidative carbonylation method for DPC synthesis has been paid more attention as it involves only one single step reaction. In the literature, oxidative carbonylation method for DPC synthesis uses homogeneous catalytic reaction. In the case, it is not easy to scale up the process due to problems of product separation and catalyst recovery. In order to solves the problems posed by homogeneous catalytic reaction, the heterogeneous catalytic technology for DPC synthesis has been proposed in the paper and investigation have been carried out as following:Screening of carriers was conducted and the result showed that the compound metal oxide LaxPbyMnOz carrier was better for DPC synthesis than others.Preparation processes of compound metal oxide LaxPbyMnOz carrier and Pd supported catalyst were studied, the results revealed that when the support was prepared by sol-gel method and under the conditions of calcining temperature 800℃ , Lanthanum–loading content 9.32 wt%, mass ratio of citric acid and total metal ion 1 to1, and the active component was loaded by precipitation with Na2PdCl4 as active substance and NaOH as precipitating agent, the catalyst showed a higher catalytic activity. The optimizing of synthesis conditions was determined by orthogonal experiments and the experimental results showed that reaction temperature was the first factor of effect on the selectivity and yield of DPC, and the concentration of O2 in gas phase also has significant effect on selectivity of DPC. The optimum reaction conditions were that catalyst/phenol mass ratio 1 to 50, pressure 4.5 MPa, the volume concentration of O2 25%, the reaction temperature 60℃ and the reaction time 4 h. d. The improvement of catalyst was also tested by loading Sn and Ce , results showed that when the co-active component Sn was added in Pd/ <WP=6>LaxPbyMnOz by co-calcination method and its loading content was equal to 14.43%, the yield and selectivity of DPC could reach 26.78% and 99% respectively, which were higher than the values reported in the literatures; and that the promoter Ce was loaded by gel-sol method and its loading content was equal to 5%, the promoter could benefit to improve the life of Pd-Sn catalyst. Deactivation and regeneration were characterized by ICP, XPS and SEM, results showed that Sn and other element migrating from inside surface to out surface of catalyst with reaction time led to the deactivation of the catalyst. e. The new instrument of measuring gas solubility was designed, and the solubility of carbon monoxide, oxygen and other gases in phenol and carbon monoxide, oxygen in phenol-tertrabutylamonium binary solvents were measured respectively under the temperature in range of 55℃ to 95℃ and gas pressure in range of 1.0 to 8.00MPa, the results showed that solubility of carbon dioxide were decreased with temperature increasing, but others were increasing; the solubility of carbon monoxide rises up with the content of tertrabutylamonium in mixing solvent increasing ,but the change trend of solubility for oxygen was reverse . By using the regular-solution theory and the virial expansion for the Redlich-Kwong equation of state, an equation was proposed to relate the solubility of the gases in the non-volatile solvent to temperature and pressure. The results revealed the equations used to correlate high-pressure gas solubility of oxygen and carbon monoxide and other gas in phenol at various temperatures were accurate. f. Kinetic experiments of DPC synthesis with heterogeneous catalytic technology in batch reactor were carried out preliminary and kinetic equations were proposed. When the reaction temperature was in range of 323K to 343K, it was ‘ ’; when the reaction temperature was in range of 347K to 353K, it was ‘ ’.更多还原