本文選題：甲烷氧化菌素 + 生物還原��； 參考：《哈爾濱商業(yè)大學(xué)》2015年碩士論文

【摘要】：本文主要采用初濕含浸法利用甲烷氧化菌素(Methanobactin, Mb)綠色合成負(fù)載型納米金催化劑并將其應(yīng)用于催化葡萄糖氧化的研究。 Mb是由甲烷氧化菌分泌到細(xì)胞外捕獲和運(yùn)輸Cu(II)的小分子熒光肽,其同時(shí)也具有螯合Au(HI)并將其還原成Au(0)的能力。實(shí)驗(yàn)第一部分對從Methylosinus trichosporium3011發(fā)酵液中提取的Mb介導(dǎo)一步還原合成納米金顆粒(Gold nanoparticles, AuNPs)進(jìn)行了研究�？疾炝瞬煌琈b濃度、反應(yīng)溫度和反應(yīng)時(shí)間對合成AuNPs的影響。通過紫外-可見光譜、熒光光譜、透射電鏡、X-射線光電子能譜和紅外光譜對合成的AuNPs進(jìn)行了表征。利用紫外-可見光譜分析表面等離子共振(Surface plasmon resonance, SPR)特征吸收峰可以證明AuNPs的形成,其最佳合成條件為：Mb:HAuCl4=10:1(mol/mol),反應(yīng)溫度為70℃,反應(yīng)時(shí)間為30min。熒光光譜分析Mb具有三個(gè)主要的特征發(fā)射峰,在加入HAuCl4時(shí)發(fā)生了熒光猝滅現(xiàn)象。利用透射電鏡分析了AuNPs的粒徑和形態(tài),其粒徑為19.3±5.5nm,主要呈圓球形。X-射線光電子能譜證明Mb將Au(Ⅲ)還原成Au(0)。通過紅外光譜分析表明,在AuNPs表面鍵合有Mb分子,增強(qiáng)了其穩(wěn)定性。 在pH1.5時(shí),葡萄糖酸鈉能夠形成內(nèi)酯,并能與羥胺-三氯化鐵絡(luò)合形成異羥肟酸-Fe3+絡(luò)合物。利用這一性質(zhì),實(shí)驗(yàn)第二部分建立了羥胺-三氯化鐵法測定催化反應(yīng)液中葡萄糖酸鈉的含量。絡(luò)合物在500nm處具有最大吸收峰。因此,在500nm處建立了葡萄糖酸鈉濃度為1～9mmol/L的標(biāo)準(zhǔn)曲線,其線性方程為y=113.0833x+0.1162,R2=0.9999,具有良好的線性線性關(guān)系。通過回收率試驗(yàn)發(fā)現(xiàn),其平均回收率為99.79%。因此可以用于測定Au/γ-Al2O3催化劑催化葡萄糖氧化反應(yīng)液中葡萄糖酸鈉的含量。 在實(shí)驗(yàn)第三部分,利用初濕含浸法由Mb介導(dǎo)原位還原制備了Au/γ-Al2O3催化劑。并用于催化葡萄糖氧化的研究�？疾炝薃u負(fù)載量、焙燒溫度以及焙燒時(shí)間對催化劑催化葡萄糖氧化比活性的影響。研究發(fā)現(xiàn),Au負(fù)載量達(dá)到1wt%時(shí),通過該方法制備的催化劑表面的AuNPs仍具有較小的粒徑(4nm)。同時(shí),通過焙燒處理部分脫除AuNPs表面鍵合的Mb分子可以提高催化劑的比活性。通過實(shí)驗(yàn)發(fā)現(xiàn),催化劑制備的最佳條件為Au負(fù)載量為1wt%,450℃焙燒處理2h,其比活性為1760.56±15.95mmol·min-1·g-1.通過X-射線光電子能譜研究發(fā)現(xiàn),催化劑前驅(qū)體的Au仍保持氧化狀態(tài)(+3價(jià)),經(jīng)Mb還原后催化劑表面Au呈零價(jià),并且焙燒處理對Au的還原狀態(tài)無影響。通過XRD分析,證明了催化劑表面AuNPs的晶體性質(zhì)。催化劑重復(fù)利用8次后,其仍具有良好的比活性,說明催化劑具有良好的催化穩(wěn)定性。本實(shí)驗(yàn)首次利用利用初濕含浸法由Mb介導(dǎo)原位還原制備了Au/γ-Al2O3催化劑用于催化葡萄糖氧化的研究。 實(shí)驗(yàn)最后一部分討論了Au/γ-Al2O3催化劑以H202作為氧化劑催化葡萄糖氧化的動(dòng)力學(xué)過程。實(shí)驗(yàn)制備了1wt%Au/γ-Al2O3催化劑,AuNPs粒徑為3.48±0.881nm,在排除傳質(zhì)阻力的影響后,確定了葡萄糖、H202、催化劑、葡萄糖酸鈉的反應(yīng)級數(shù)(0.4696、0.3729、0.4088、-0.9794),建立了冪指數(shù)速率模型。通過阿倫尼烏斯曲線確定了該催化劑的活化能為6.114kJ/mol。此外,通過已有數(shù)據(jù)建立了Langmuir-Hinshelwood動(dòng)力學(xué)模型,最終發(fā)現(xiàn)預(yù)測值與實(shí)驗(yàn)值有較好的擬合性。 本文通過初濕含浸法利用Mb介導(dǎo)原位還原制備了Au/γ-Al2O3催化劑,并成功用于液相催化葡萄糖氧化研究,催化劑具有較高的比活性和穩(wěn)定性。同時(shí),本文催化劑的“綠色”制備具有良好的應(yīng)用前景。
[Abstract]:In this paper, a supported gold nanoparticle catalyst was synthesized by the green synthesis of Methanobactin (Mb) in the initial wet leaching process and applied to the study of the catalytic glucose oxidation.
Mb is a small molecular fluorescent peptide secreted by methane oxidizing bacteria to capture and transport Cu (II) outside the cell, and it also has the ability to chelate Au (HI) and reduce it to Au (0). The first part of the experiment was carried out by the Mb mediated one step synthesis of gold nanoparticles (Gold nanoparticles, AuNPs) from the Methylosinus trichosporium3011 fermentation broth. The effects of different Mb concentration, reaction temperature and reaction time on the synthesis of AuNPs were investigated. The synthesized AuNPs was characterized by UV visible spectrum, fluorescence spectrum, transmission electron microscope, X- ray photoelectron spectroscopy and infrared spectroscopy. The characteristics of the surface ion resonance (Surface plasmon resonance, SPR) were analyzed by UV visible spectroscopy. The peak collection can prove the formation of AuNPs. The optimum synthesis conditions are: Mb:HAuCl4=10:1 (mol/mol), the reaction temperature is 70 C, the reaction time is 30min. fluorescence spectrum analysis, Mb has three main characteristic emission peaks, and the fluorescence quenching occurs when HAuCl4 is added. The particle size and morphology of AuNPs are analyzed by transmission electron microscopy, the particle size is 19.3 + 5. .5nm, mainly circular spherical.X- ray photoelectron spectroscopy, proved that Mb reduced Au (III) to Au (0). The IR spectrum analysis showed that the bonding of Mb molecules on the surface of AuNPs enhanced its stability.
At pH1.5, sodium gluconate can form lactone and can form a hydroxamic acid -Fe3+ complex with hydroxylamine trichloride. Using this property, the second part of the experiment established the content of sodium gluconate in the catalytic reaction liquid by hydroxylamine trichloride method. The complex has the maximum absorption peak at 500nm. Therefore, it has been established at 500nm. The concentration of sodium gluconate is 1 ~ 9mmol/L standard curve, its linear equation is y=113.0833x+0.1162, R2=0.9999, and has a good linear linear relationship. The recovery rate test shows that the average recovery rate is 99.79%., so it can be used to determine the content of sodium gluconate in the catalytic glucose oxidation reaction of Au/ gamma -Al2O3 catalyst.
In the third part of the experiment, the Au/ gamma -Al2O3 catalyst was prepared by Mb mediated in situ reduction by the initial wetting method and used to catalyze the oxidation of glucose. The effect of Au load, calcination temperature and calcination time on the catalytic activity of the catalyst on the catalyst glucose oxidation was investigated. It was found that the method was prepared by this method when the load of Au was 1wt%. The AuNPs on the surface of the catalyst still has a smaller particle size (4nm). At the same time, the specific activity of the catalyst can be enhanced by the removal of the Mb molecule with the surface bonding of the AuNPs surface by roasting. The best condition for the preparation of the catalyst is that the Au load is 1wt% and the 2H is calcined at 450 C, and its specific activity is 1760.56 + 15.95mmol. Min-1. G-1.. The X- ray photoelectron spectroscopy study found that the Au of the precursor of the catalyst still maintained the oxidation state (+3 valence), and the catalyst surface Au was zero after Mb reduction, and the calcination treatment had no effect on the reduction state of the Au. The crystal properties of the AuNPs on the surface of the catalyst were proved by XRD analysis. After 8 times the reuse of the catalyst, the catalyst still had a good specific activity. It shows that the catalyst has good catalytic stability. In this experiment, Au/ gamma -Al2O3 catalyst was used to catalyze the oxidation of glucose by Mb in situ reduction.
The last part of the experiment discussed the kinetic process of Au/ gamma -Al2O3 catalyst using H202 as an oxidizing agent to catalyze the oxidation of glucose. The 1wt%Au/ gamma -Al2O3 catalyst was prepared by experiment. The particle size of AuNPs was 3.48 + 0.881nm. After removing the influence of mass transfer resistance, the reaction progression of glucose, H202, catalyst and sodium gluconate was determined (0.4696,0.3729,0.4088). -0.9794), the power exponent rate model was established. The activation energy of the catalyst was determined to be 6.114kJ/mol. by the Arrhenius curve. The Langmuir-Hinshelwood kinetic model was established through the existing data. Finally, the predicted value was better than the experimental value.
In this paper, Au/ gamma -Al2O3 catalyst was prepared by Mb mediated in situ reduction by initial wet leaching. The catalyst has been successfully used in the study of liquid phase catalytic glucose oxidation. The catalyst has high specific activity and stability. At the same time, the "green" preparation of the catalyst has a good application prospect.

【學(xué)位授予單位】：哈爾濱商業(yè)大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：O643.36;TB383.1

【參考文獻(xiàn)】

相關(guān)期刊論文 前1條

1 唐月;胡紅定;朱明喬;王萌;郝雨;陳新志;;活性炭負(fù)載的納米金催化劑上葡萄糖氧化工藝[J];化學(xué)反應(yīng)工程與工藝;2012年03期

相關(guān)博士學(xué)位論文 前1條

1 倪吉;氧化物負(fù)載納米金用于綠色催化選擇還原與氧化反應(yīng)研究[D];復(fù)旦大學(xué);2012年

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本文編號：1882595