本文選題：ZnO納米線/大孔SiO2復(fù)合材料　切入點：吸波載體　出處：《寧波大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

【摘要】：本文通過原位水熱生長法將ZnO納米線成功引入大孔SiO2的三維孔道中,得到ZnO納米線/大孔SiO2復(fù)合材料(ZnO NWs/SiO2)。然后采用SEM和XRD對復(fù)合材料的形貌和結(jié)構(gòu)進(jìn)行表征。1.ZnO NWs/SiO2復(fù)合材料被用作載體通過靜電吸附固定C.antarctica lipase B(CALB)。高的比表面積(233 m2/g)和強的靜電作用力使得ZnO NWs/SiO2復(fù)合載體的平均吸附量達(dá)到196.8 mg/g。ZnO NWs/SiO2復(fù)合載體吸附量達(dá)到大孔SiO2的3-4倍,接近于硅基介孔材料的吸附量。ZnO NWs/SiO2-CALB浸泡在PBS緩沖溶液中48 h,ZnO NWs/SiO2的吸附量及ZnO NWs/SiO2-CALB的酶活性幾乎不變。然后ZnO NWs/SiO2-CALB被用于催化拆分2-辛醇。ZnO NWs/SiO2復(fù)合載體固定化C.antarctica lipase B(CALB)催化拆分2-辛醇的最佳反應(yīng)體系為:1.0 M(R,S)-2-辛醇,2.0 M乙酸乙烯酯,4.0 wt.%水含量,196.8mg/g酶負(fù)載量,60°C下反應(yīng)8 h。在此條件下,ZnO NWs/SiO2-CALB催化拆分2-辛醇反應(yīng)的底物轉(zhuǎn)化率為49.1%,產(chǎn)物(R)-2-辛醇酯的對映體過量值(eep)為99%。此外,ZnO NWs/SiO2-CALB展示了較好的操作穩(wěn)定性,重復(fù)使用15次后ZnO NWs/SiO2-CALB仍保留96.9%的相對活性和93.8%的相對選擇性。2.ZnO NWs/SiO2作為一種新型的微波吸附材料被作為載體固定化Candida rugosa lipase(CRL)。微波輔助條件下ZnO NWs/SiO2-CRL被用于催化植物甾醇與油酸的酯化反應(yīng)合成植物甾醇酯。在ZnO納米線的存在下ZnO NWs/SiO2固定化酶的催化活性得到了較大的提高。研究證明,ZnO納米線的微波吸附性能對微波與酶的協(xié)同作用有較大的幫助。相比傳統(tǒng)加熱,微波輔助加熱條件下ZnO NWs/SiO2復(fù)合載體固定Candida rugosa lipase(CRL)展示較高的熱穩(wěn)定性。ZnO NWs/SiO2復(fù)合載體固定Candida rugosa lipase(CRL)在微波輔助加熱條件下催化植物甾醇與油酸的酯化反應(yīng)的最佳反應(yīng)條件為:植物甾醇(0.1 M),酸醇摩爾比(2/1),水活度(0.11),溫度(50°C),時間(1 h)。在此條件下,酯化反應(yīng)的底物轉(zhuǎn)化率為95.4%,得到了630-650 mg的植物甾醇酯(酶含量為20 mg)。
[Abstract]:This paper by in situ hydrothermal growth method of three-dimensional pore ZnO nanowires into the macroporous SiO2, ZnO nanowires / macroporous SiO2 composites (ZnO NWs/SiO2). Then the morphology and structure of SEM and XRD of the composite was characterized by.1.ZnO NWs/SiO2 composite materials were used as carrier C.antarctica lipase B by electrostatic adsorption and fixation (CALB). The high specific surface area (233 m2/g) 3-4 times and the strong electrostatic interaction makes the average adsorption of ZnO NWs/SiO2 composite carrier reached 196.8 mg/g.ZnO NWs/SiO2 composite carrier macroporous adsorption capacity reached SiO2, close to the silica based mesoporous materials.ZnO adsorption was soaked in NWs/SiO2-CALB PBS buffer solution h 48. The activity of ZnO NWs/SiO2 and ZnO NWs/SiO2-CALB the adsorption capacity is almost unchanged. The ZnO NWs/SiO2-CALB was then used to 2-.ZnO NWs/SiO2 octanol catalyzed resolution composite carrier immobilized C.antarctica lipase B (CA LB) the optimal reaction system for 2- octanol catalyzed resolution: 1 M (R, S) -2- octanol, 2 M acetate, 4 wt.% water content 196.8mg/g, enzyme loading, reaction conditions in 8 h. 60 ~ C, ZnO NWs/SiO2-CALB 2- octanol catalyzed resolution reaction substrate conversion rate is 49.1%, the product (R) -2- octyl ester enantiomeric excess (EEP) for 99%. ZnO in addition, NWs/SiO2-CALB shows good operational stability, repeated use of relative activity after 15 ZnO and 93.8% NWs/SiO2-CALB still retained 96.9% of the relative selectivity of.2.ZnO NWs/SiO2 as a new type of micro wave absorbing material was used as the carrier for immobilization of Candida rugosa lipase (CRL) under microwave irradiation. ZnO NWs/SiO2-CRL was used in the esterification synthesis of phytosterol esters of sterols and oleic acid catalytic plant. The catalytic activity of ZnO NWs/SiO2 immobilized enzyme in the presence of ZnO nanowires have been greatly improved. Proved that the synergistic effect of microwave adsorption properties of ZnO nanowires on microwave and enzyme are helpful. Compared with conventional heating, microwave heating under the condition of ZnO NWs/SiO2 Candida rugosa lipase fixed carrier composite (CRL) thermal stability of.ZnO NWs/SiO2 composite carrier show higher fixed Candida rugosa lipase (CRL) reaction conditions in microwave assisted heating conditions catalyzed by phytosterols and oleic acid as plant sterols (0.1 M), molar ratio of acid to alcohol (2/1), water activity (0.11), temperature (50 degrees C), time (1 h). Under this condition, the esterification reaction of the substrate conversion rate was 95.4%, 630-650 of phytosterol esters Mg (the enzyme content was 20 mg).

【學(xué)位授予單位】：寧波大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：TB383.1;Q814.2

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本文編號：1567074