Preparation Of Aluminum Phosphate-based Ni-based Catalysts And Research On The Hydrogenation Of ?-pinene

?-Pinene is the main component of turpentine,and its major hydrogenation product,cis-pinane,is an important immediate with high added value in spice industry.Therefore,the preparation of highly cis-selective pinane has been a hot topic in the research of forest chemistry.Generally,there are two main routes utilized for increasing the selectivity of cis-pinane including the preparation of the catalyst with excellent performance and the optimization of the hydrogenation process.The supported nickel shows good catalytic performance for the hydrogenation of?-pinene,and the key route to improve the performance of the Ni catalysts is to select proper supports.?-Pinene is also a common solvent in chemical science,yet its application in material synthesis was few reported.Thence the use of?-pinene in the synthesis of functional materials is of great worth for the application of turpentine.The aluminophosphate molecular sieves are common catalyst supports,which possess excellent structural morphology and thermal stability.They are widely applied in catalysis,while their applications in resin chemistry are rarely reported.The use of aluminophosphate molecular sieves for resin chemistry is of great significance for broadening its application and further enhancing the deep processing of turpentine.In this thesis,?-pinene was firstly used as the solvent for synthesis of aluminophosphate,and the product was used as support to prepare catalysts by loading nickel and nickel-phosphor.The catalysts were characterized and analyzed by XRD,N2-sorption,SEM-EDS,TEM,TG-DSC,XPS,TPR,TPO and IR,and then used for hydrogenation of?-pinene.The main contents and conclusions are as follows:1.Synthesis of aluminophosphate using?-pinene as solvent.The aluminophosphate with hexagonal structure and AFI topology(noted as“APO-BAA”)was synthesized by conventional solvothermal method using triethylamine as the template.The product emerged prism morphology with BET specific surface area of 289.36 m~2/g and mesoporous structure,and showed excellent thermal stability.The apparent active energies for the procedures of nuclear and growth were 65.65 kJ/mol and 92.94 kJ/mol,respectively.The aluminophosphate with tridymite type(noted as“APO-BBA”)was synthesized by conventional solvothermal method using triethanolamine as the template.The product emerged flaky morphology with BET specific surface area of 131.43 m~2/g and mesoporous structure,and showed excellent thermal stability.The aluminophosphate with amorphous structure and“sticky”morphology(noted as“APO-BCB”)was synthesized by microwave-assistant solvothermal method firstly using dehydroabietylamine as the template.The product was micro-and meso-porous with the BET specific surface area of 272.00 m~2/g and huge pore volume of 0.7 cm~3/g.It also showed good thermal stability that could maintain its amorphous structure after calcination.2.The synthesized aluminophosphates were used as supports to prepare catalysts by loading nickel for the hydrogenation of?-pinene.The catalyst Ni/APO-BAA was prepared and the correlation among loading condition,catalyst composition and catalytic performance was associated.The hydrogenation process was optimized through Miscellaneous Design.At the optimal condition,the conversion of?-pinene(Abbreviated as“conversion”)was 98.5%and the selectivity of cis-pinene(Abbreviated as“selectivity”)was 96.2%.The process was repeatable and the catalyst could maintain good performance after 7 cycles.In this catalytic system,the procedures of pinene conversion,cis-pinane and trans-pinane formation conformed to pseudo first-order kinetics,and the activation energies for the three procedures were 42.01,41.13 and 54.62 kJ/mol.The catalyst Ni/APO-BBA was prepared and the correlation among loading condition,catalyst composition and catalytic performance was associated.The hydrogenation process was optimized through Box-Behnken Design(BBD).The conversion and the selectivity were 94.8%and 95.1%at optimal condition.The process was repeatable and the catalyst could maintain good performance after 5 cycles.The catalyst Ni/APO-BCB was prepared.The catalyst showed excellent performance that the conversion and the selectivity were 98.2%and 95.9%,respectively.The catalyst Ni-P/APO-BAA was prepared by chemical reduction method,and the correlation between loading condition and catalytic performance was investigated through BBD and XPS analysis.The hydrogenation process was optimized through Orthogonal Design(OGD).The conversion and the selectivity were 99.0%and 97.9%at the optimal condition,which was close to the catalytic effect of precious metals.The process was repeatable and the catalyst could maintain excellent performance after 10 cycles.In this catalytic system,the procedures of pinene conversion,cis-pinane and trans-pinane formation conformed to pseudo first-order kinetics,and the activation energies for the three procedures were 62.64,61.90 and 91.93 kJ/mol.3.A comparison among the catalysts was carried out.It could be summarized that the thermal stability and oxidation resistance of the active centers were improved when using aluminophosphates as supports.The performance of the catalysts prepared in this study was comparable to or better than the current common nickel catalysts,and that of Ni-P/APO-BAA was close to the precious metal catalyst.The reason for the improvement of performance might be the guiding effect of?-pinene as a solvent during the preparation of the support.