本文選題：鎂鉻尖晶石 + 熔鹽法�。� 參考：《南昌大學(xué)》2010年碩士論文

【摘要】：熔鹽合成法是近代發(fā)展起來(lái)的一種無(wú)機(jī)材料合成方法。它采用一種或幾種低熔點(diǎn)的鹽類作為反應(yīng)介質(zhì),在高溫熔融鹽中完成合成反應(yīng),然后采用合適的溶劑將鹽類溶解,經(jīng)過(guò)濾、洗滌得到合成產(chǎn)物。由于熔鹽合成法具有工藝簡(jiǎn)單、成本低廉、合成溫度低、保溫時(shí)間短、合成產(chǎn)物的化學(xué)成分穩(wěn)定均勻等優(yōu)點(diǎn),因而在合成高熔點(diǎn)氧化物粉體和電子陶瓷粉體及其它功能粉體材料等領(lǐng)域廣泛應(yīng)用。 本文在NaCl、KCl熔鹽介質(zhì)中合成了鎂鉻尖晶石粉體,研究了原料種類、熱處理溫度和保溫時(shí)間、熔鹽的種類對(duì)鎂鉻尖晶石粉體性能的影響,同時(shí)對(duì)鎂鉻尖晶石應(yīng)用于汽車尾氣凈化器載體進(jìn)行了研究。研究發(fā)現(xiàn),氧化鉻、結(jié)晶氯化鉻、結(jié)晶硝酸鉻均能與結(jié)晶氯化鎂和碳酸鈣原料反應(yīng)生成鎂鉻尖晶石,MgCl2·6H2O、CaCO3、Cr2O3、NaCl、KCl原料在900℃下保溫5小時(shí)熱處理制備的鎂鉻尖晶石晶體分布最為均勻,大部分為八面體形貌,晶體生長(zhǎng)完全,Cr(NO3)3.9H2O和CrCl3.6H2O等鉻鹽制備的鎂鉻尖晶石,除了少部分呈八面體形貌外,大部分生長(zhǎng)不完整,為形狀不規(guī)則的鎂鉻尖晶石顆粒；隨著熱處理溫度的升高和保溫時(shí)間的延長(zhǎng),鎂鉻尖晶石晶體的結(jié)晶度有所提高,顆粒粒徑增大；NaCl熔鹽介質(zhì)中,鎂鉻尖晶石晶體生長(zhǎng)的表觀活化能Ea=10.01 KJ/mol。所制備的蜂窩型鎂鉻尖晶石多孔陶瓷作為汽車尾氣處理用催化劑載體在形狀、網(wǎng)格尺寸方面均能達(dá)到使用標(biāo)準(zhǔn),所制備的鎂鉻尖晶石多孔陶瓷具有多孔隙、孔徑分布均勻、比表面積大等優(yōu)點(diǎn),可以很均勻地吸附和儲(chǔ)存催化劑,為達(dá)到理想的凈化效果創(chuàng)造了條件。
[Abstract]:Molten salt synthesis is a kind of inorganic material synthesis method developed in modern times. It uses one or more low melting point salts as the reaction medium to complete the synthesis reaction in the high temperature molten salt, then dissolves the salt in the suitable solvent, after filtration, the synthesis product is obtained. Because of the advantages of simple process, low cost, low synthesis temperature, short holding time and stable and uniform chemical composition of the product, the molten salt synthesis method has the advantages of simple process, low cost, low synthesis temperature, short heat preservation time, etc. Therefore, it is widely used in the synthesis of high melting point oxide powder, electronic ceramic powder and other functional powder materials. In this paper, magnesium-chromium spinel powder was synthesized in NaCl-KCl molten salt medium. The effects of raw materials, heat treatment temperature, holding time and molten salt on the properties of magnesium-chromium spinel powder were studied. At the same time, the application of magnesium-chromium spinel in the carrier of automobile exhaust purifier was studied. It was found that the crystal distribution of magnesium-chromium spinel can be obtained by the reaction of Cr _ 2O _ 3, Cr _ 2O _ 3 and Cr _ (No3) _ 3 with the raw materials of magnesium chloride and calcium carbonate. Most of them are octahedral, and the magnesium-chromium spinel which is prepared by Cr (No3) 3.9H2O and CrCl3.6H2O completely grows, except for a few octahedral morphology, most of them are incomplete and irregular shape magnesia-chrome spinel. With the increase of heat treatment temperature and the prolongation of holding time, the crystallinity of magnesium-chromium spinel crystal is increased, and the apparent activation energy of crystal growth of magnesia-chrome spinel in NaCl molten salt medium is increased, and the apparent activation energy (EA) 10.01 KJ / mol is obtained. The honeycomb magnesia-chrome spinel porous ceramics used as catalyst carrier for automobile tail gas treatment can meet the application standard in shape and mesh size. The prepared porous ceramics have many pores and uniform pore size distribution. Because of its large specific surface area, the catalyst can be uniformly adsorbed and stored, which creates the conditions for achieving the ideal purification effect.
【學(xué)位授予單位】：南昌大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2010
【分類號(hào)】：TB321;U464.13

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 田中青,劉韓星,余洪滔,歐陽(yáng)世翕;微波介質(zhì)陶瓷粉體的合成方法研究[J];材料導(dǎo)報(bào);2003年12期

2 曹健，，謝嘉寧，張業(yè)鳳;熔鹽法合成BaFe_（11）Co_（0．5）Ti_（0．5）O_（19）磁性粉體[J];功能材料;1996年05期

3 李穎;王寶玉;師素環(huán);趙洪波;程遠(yuǎn);;RH爐用高性能電熔再結(jié)合鎂鉻磚的研制[J];耐火與石灰;2008年04期

4 朱伯銓;李雪冬;郝瑞;汪厚植;;在硫酸鈉熔鹽中合成莫來(lái)石的熱力學(xué)研究[J];硅酸鹽學(xué)報(bào);2006年01期

5 王健東;潘波;楊曉峰;;RH爐用高級(jí)鎂鉻磚的研究與侵蝕機(jī)理分析[J];煉鋼;2007年04期

6 黃衛(wèi)國(guó);熔鹽法合成納米MgAl_2O_4粉[J];耐火材料;2002年05期

7 李日升;鎂鉻尖晶石粉體材料的制取及應(yīng)用[J];中國(guó)搪瓷;2003年Z1期

8 宋煜昕,李承恩,晏海學(xué);熔鹽法合成SrBi_2Ta_2O_9粉體[J];無(wú)機(jī)材料學(xué)報(bào);2002年01期

9 郝華,羅大兵,劉韓星,歐陽(yáng)世翕;熔鹽法合成SrBi_4Ti_4O_(15)片狀鐵電陶瓷粉末[J];武漢理工大學(xué)學(xué)報(bào);2004年01期

10 張冰,曹傳寶,許亞杰,朱鶴蓀;熔鹽法合成莫來(lái)石晶須[J];無(wú)機(jī)化學(xué)學(xué)報(bào);2005年02期

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