【作者】 梁亚男；

【导师】 程庆彦；

【作者基本信息】 河北工业大学 ， 化学工艺， 2008， 硕士

【摘要】 均相催化剂虽然活性高但往往难以分离且有腐蚀性,而多相催化剂则易于分离、再生和回收使用。为使甲醇液相氧化羰基化催化剂兼具均相与多相催化剂的优点,首次采用微波固相法,进行了SiO₂负载含氮配体金属铜配合物催化剂的制备、表征及催化性能的研究,并优化了反应条件。采用微波固相法制备了纳米SiO₂负载咪唑、2-甲基咪唑、1,10-邻菲啰啉、2-氨基吡啶和3-氰基吡啶多种金属配合物催化剂。采用FT-IR、UV-vis、XPS等分析方法对产物进行了表征,结果表明,配体中氮原子与金属间形成了配位键,负载型配合物已成功制备出。考察了制备条件以及催化反应条件对甲醇液相氧化羰基化反应中催化剂性能的影响,在反应条件为120℃, Po₂=0.8 MPa, Pco=1.6 MPa, 2 h, c（Cu）=0.10 mol/L, n（2-氨基吡啶）:n（CuCl₂）=1:1,MI time=10 min时,DMC收率可达7.10 %,远高于纯氯化铜催化剂的2.89 %。并且随着反应压力和时间的增加,DMC收率呈递增的趋势。采用偶联剂γ-氯丙基三乙氧基硅烷对纳米SiO₂进行表面改性制备载体“Si-Cl”,优化了改性条件。采用微波固相法制备了载体“Si-Cl”接枝咪唑、2-甲基咪唑、N-甲基咪唑、2-氨基吡啶和哌嗪多种金属配合物催化剂。采用XPS、FT-IR、UV-vis、BET等分析方法对产物进行了结构确定,结果表明,修饰的纳米SiO₂其端基氯基与配体N-H中的氢原子发生了交换,配合物中氮原子与金属间形成了配位键。将制备的催化剂应用于甲醇液相氧化羰基化反应中,在反应条件为120℃, P_CO:P_O2=2:1, 2.4 MPa, 2 h, n（IM）:n（CuCl₂）=2:1, c(Cu²⁺)=0.016 mol/L条件下,以咪唑为配体的催化剂Si-IM-CuCl₂的DMC收率可达3.69 %,远高于纯CuCl₂的0.79 %,取得了较好的催化效果。纳米SiO₂负载咪唑-CuCl₂配合物催化剂与“Si-Cl”接枝该配合物催化剂在120℃, P_CO:P_O2=2:1, 2.4 MPa, 2 h, n（IM）:n（CuCl₂）=2:1, c(Cu²⁺)=0.016 mol/L反应条件下DMC收率分别为3.65 %和3.69 %,催化性能基本相同,然而接枝型咪唑-CuCl₂配合物催化剂在该反应条件下选择性为97.62 %,远高于SiO₂负载咪唑-CuCl₂配合物催化剂的84.67 %,且接枝型配合物催化剂在反应过程中损失量较小,回收利用性较强。更多还原

【Abstract】 Homogeneous catalyst is environmentally unfriendly for it can’t separate from reaction system easily and has corrosive effect on the reactor material. However, heterogeneous catalyst has some attractive advantages for removing from reaction mixtures easily and can recycle use. This thesis deals with the preparation, characterization and catalytic reactivity in the liquid phase oxidative carbonylation of nano-silica-supported N-CuCl₂ complex catalysts.Silica-supported IM, 2-MIM, Phen, 2-AP, 3-CP-CuCl₂ complexes, were synthesized by solid-state microwave irradiation for the first time and then characterized by XPS, FT-IR, UV-vis and so on. The results show that the ligands have been connected with metal ion by covalent bond, and the supported-complexes have been prepared successfully by microwave irradiation. The supported-complexes were used as heterogeneous catalyst in oxidative carbonylation of methanol, the effects of preparation factors and reaction conditions on catalytic activity were studied. Under the reaction condition of 120℃, Po2=0.8 MPa, Pco=1.6 MPa, 2 h, c（CuCl₂）=0.10 mol/L, n（2-AP）:n（CuCl₂）=1:1,MI time=10 min, the yield of DMC can reach about 7.10 % which is higher than 2.89 % for pure CuCl₂ under the same reaction conditions, and the yield of DMC increases along with the increasion of reaction pressure and time.Nano-Silica was modified byγ-chloropropyltriethoxysilane to synthesis“Si-Cl”, and the reaction conditions were studied. The“Si-Cl”which grafted IM, 2-MIM, N-MIM, 2-AP, PI-CuCl₂ complexes, were prepared by solid-state microwave irradiation for the first time. The resultant materials were characterized by various techniques such as XPS, FT-IR, UV-vis, BET and so on. The results show that the N atom has been connected with Cu2+ by covalent bond, and the grafted-complexes catalysts have been prepared successfully under microwave irradiation. The grafted-complexes were used as heterogeneous catalyst in oxidative carbonylation of methanol, and its catalytic activity was studied. Under the reaction condition of 120℃, P_CO:P_O2=2:1, 2.4 MPa, 2 h, n（IM）:n（CuCl₂）=2:1, c(Cu²⁺)=0.016 mol/L, the yield of DMC can reach about 3.69 % which is higher than 0.79 % for pure CuCl₂ under the same reaction conditions.With IM-CuCl₂/SiO₂ and Si-IM-CuCl₂ as catalyst for oxidative carbonylation of methanol, under the same reaction condition of 120℃, P_CO:P_O2=2:1, 2.4 MPa, 2 h, n（IM）:n（CuCl₂）=2:1, c(Cu²⁺)=0.016 mol/L, the yield of DMC is 3.65 % and 3.69 %, the numerical is similar the same. But the selectivity is 97.62 % with Si-IM-CuCl₂ as catalyst which is higher than 84.67 % with IM-CuCl₂/SiO₂ as catalyst, and“Si-Cl”is connected by chemical bond with complex catalyst, which has less loss and more easily removal from reaction mixtures.更多还原