本文選題：氣溶膠　切入點：負(fù)載貴金屬顆粒微球　出處：《大連理工大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

【摘要】：負(fù)載貴金屬顆粒微球能夠很好的綜合貴金屬催化劑獨特的物化性能以及顆粒微球載體的優(yōu)勢,因此賦予了負(fù)載貴金屬顆粒微球較多新的優(yōu)異性能：貴金屬活性組分高度分散,活性催化組分與載體之間的強(qiáng)相互作用,材料良好的的化學(xué)以及催化穩(wěn)定性能,成本低廉等,因此在環(huán)境保護(hù),石油化工,新能源等領(lǐng)域具有較高的應(yīng)用價值。本論文主要用氣溶膠一步法合成負(fù)載貴金屬催化劑的多孔微球并考察了它們的液相反應(yīng)催化性能,主要研究內(nèi)容如下：本論文采用氣溶膠一步法合成了Fe304@C-Si0：磁性核殼微球,其中Fe3O4為核,殼層為C-SiO2結(jié)構(gòu),將該核殼微球作為模板合成Fe3O4@C-SiO2@ RF-COOH顆粒微球,(RF-COOH:樹脂),隨后經(jīng)高溫石墨化、NaOH腐蝕等階段得到最終產(chǎn)品C-C@Fe3O4磁性多孔微球,并且在該反應(yīng)過程中,模板Fe3O4@C-SiO2核殼微球的Fe3O4核分裂成更小粒徑并均勻分散到C-C@Fe3O4顆粒微球的外層介孔碳中,因此該微球的磁性得到很大的增強(qiáng)(磁性強(qiáng)度由2.4 emu/g增大到11.0 emu/g),提高近四倍之多。C-C@Fe3O4顆粒微球可作為Pt的理想載體,則得到可回收再利用的C-C@Fe3O4-Pt磁性微球,并探究了該微球催化還原對硝基苯酚(4-NP)至對氨基苯酚(4-AP)的性能。結(jié)果發(fā)現(xiàn)C-C@Fe3O4-Pt微球催化還原4-NP性能優(yōu)異,并且可通過外加磁場可將C-C@Fe3O4-Pt微球?qū)崿F(xiàn)快速有效回收,同時5次循環(huán)反應(yīng)后微球催化效率仍達(dá)99%以上。為了繼續(xù)體現(xiàn)用氣溶膠法制備負(fù)載貴金屬顆粒微球的優(yōu)勢,采用一步水熱法合成出粒徑均勻、分散性好的M@RF-COOH (M:Pt、Au或者Au/Pt合金)納米微球,其中顆粒微球的粒徑和貴金屬納米顆粒的組分可以調(diào)控,然后以M@RF-COOH微球為模板利用氣溶膠一步法將貴金屬顆粒嵌入介孔二氧化硅微球載體中,隨后煅燒去掉樹脂,最終得到M@Si02顆粒微球,并研究了其催化還原4-NP的性能。結(jié)果發(fā)現(xiàn)形成貴金屬核殼結(jié)構(gòu)的Au/Pt@SiO2, Pt@SiO2微球的催化性能為其他微球的9-14倍,并且5次循環(huán)反應(yīng)后核殼結(jié)構(gòu)的貴金屬活性組分以及高度有序的二氧化硅介孔保存完整,顯現(xiàn)出其優(yōu)異的催化穩(wěn)定性。為了進(jìn)一步拓展負(fù)載貴金屬顆粒微球催化液相反應(yīng)的范圍,采用水熱法制備出粒徑均勻的RF-COOH微球,然后以該微球為載體,通過浸漬還原法得到HRF-COOH-Pt微球。該顆粒微球用來催化氨硼烷(AB)水解,結(jié)果表明：HRF-COOH-Pt微球催化AB水解性能優(yōu)異,其中在30℃下RF-COOH-Pt (6mL K2PtCl6)微球在約80s的時間內(nèi)催化10mL3.5mg/mL的AB溶液水解徹底,測得還原反應(yīng)活化能Ea為37.88 kJ/mol。微球經(jīng)過5次循環(huán)后,其催化性能沒有衰減。
[Abstract]:The loaded noble metal particle microspheres can well integrate the unique physical and chemical properties of noble metal catalysts and the advantages of the particle microspheres carrier. Therefore, the loaded noble metal particle microspheres have many new and excellent properties: the noble metal active components are highly dispersed. Strong interaction between active catalytic components and carriers, good chemical and catalytic stability of materials, low cost, etc., therefore in environmental protection, petrochemical, In this thesis, porous microspheres supported on noble metal catalysts were synthesized by aerosol one-step method and their catalytic properties of liquid phase reaction were investigated. The main contents of this paper are as follows: in this paper, the Fe304C-Si0: magnetic core-shell microspheres were synthesized by a one-step aerosol method, with Fe3O4 as the core and the shell as the C-SiO _ 2 structure. The core-shell microspheres were used as templates to synthesize Fe3O4C-SiO2 @ RF-COOH microspheres and RF-COOHH: resin. After high temperature graphitization and NaOH corrosion, the final product C-CCOO4 magnetic porous microspheres were obtained. The Fe3O4 nuclei of the template Fe3O4@C-SiO2 core-shell microspheres were split into smaller particles and dispersed evenly into the outer mesoporous carbon of the C-C Fe3O4 microspheres. Therefore, the magnetic properties of the microspheres were greatly enhanced (the magnetic intensity of the microspheres increased from 2.4 emu/g to 11.0 emu / g / g, and the increase of the magnetic intensity was nearly four times. C-Cr Fe _ 3O _ 4 microspheres could be used as ideal support for Pt, and a recoverable C-C _ C _ 3O _ 4-Pt magnetic microspheres were obtained. The catalytic reduction of 4-NP from p-nitrophenol to p-aminophenol (4-APP) by the microsphere was studied. The results showed that the catalytic reduction of 4-NP by C-CC@ Fe3O4-Pt microspheres was excellent, and C-CFe3O4-Pt microspheres could be recovered quickly and effectively by applying magnetic field. At the same time, the catalytic efficiency of the microspheres is still over 99% after five cycles. In order to continue to reflect the advantage of the aerosol method in preparing the loaded noble metal particle microspheres, the particle size of the microspheres prepared by one step hydrothermal method is uniform. The size of the particles and the composition of the noble metal nanoparticles can be controlled. Then, using M@ RF-COOH microspheres as template, the noble metal particles were embedded into mesoporous silica microspheres by one step aerosol method, and then the resin was removed by calcination, and finally the M@ Si02 microspheres were obtained. The catalytic reduction of 4-NP was studied. The results showed that the catalytic performance of au / Pt Sio _ 2 and Pt@SiO2 microspheres was 9-14 times higher than that of other microspheres. After five cycles, the active components of the core and shell structure and the highly ordered mesoporous silica were preserved intact. In order to further expand the range of liquid phase reaction catalyzed by loaded noble metal particle microspheres, RF-COOH microspheres with uniform particle size were prepared by hydrothermal method, and then the microspheres were used as the carrier. HRF-COOH-Pt microspheres were prepared by impregnation reduction method. The particle microspheres were used to catalyze the hydrolysis of ABB. The results showed that the catalytic activity of the HRF-COOH-Pt microspheres on AB hydrolysis was excellent, and the RF-COOH-Pt 6mL K2PtCl6 microspheres were hydrolyzed thoroughly in 10 mL L 3.5mg / mL AB solution at 30 鈩，

本文編號：1604941