本文選題：仲鎢酸銨 + 三氧化鎢　； 參考：《昆明理工大學(xué)》2015年碩士論文

【摘要】：傳統(tǒng)煅燒制備三氧化鎢的方法存在以下缺點(diǎn)：生產(chǎn)時間長,生產(chǎn)成本高,能耗大,產(chǎn)品質(zhì)量難以保證的缺點(diǎn)。而微波煅燒制備三氧化鎢的方法不僅縮短了生產(chǎn)時間,降低了生產(chǎn)成本和能耗,還得到合格率較好的產(chǎn)品。本文首先采用微波加熱爐對仲鎢酸銨進(jìn)行加熱,研究仲鎢酸在微波場中的升溫行為,分別探討微波功率、物料量和加熱時間對溫度的影響,還通過微波諧振腔法測定仲鎢酸銨的吸波特性。接著通過多因素正交試驗(yàn)確定最佳工藝條件。并且對仲鎢酸銨傳統(tǒng)制備三氧化鎢的工藝進(jìn)行了研究,考察了煅燒溫度、熱分解速度、爐管轉(zhuǎn)速和爐內(nèi)抽氣速度對三氧化鎢制備過程的影響；同時采用傳統(tǒng)熱重分析儀對仲鎢酸銨進(jìn)行測定,并分析了仲鎢酸銨在常規(guī)條件下的熱分解特性；隨后在最佳工藝條件下,采用單模腔微波熱重分析系統(tǒng)對仲鎢酸銨進(jìn)行微波熱重分析,探討仲鎢酸銨在微波場中的熱分解特性,并與仲鎢酸銨常規(guī)熱分解特性進(jìn)行對比。最后對三氧化鎢產(chǎn)物進(jìn)行XRD和SEM表征。研究結(jié)果表明：仲鎢酸銨在頻率2.450GHz的微波場中具有良好的吸波特性,并且仲鎢酸銨在微波場中的升溫與微波功率成正比,與物料量成反比關(guān)系,物料溫度隨著微波加熱時間的延長而逐漸升高；通過正交優(yōu)化試驗(yàn)確定了最佳工藝條件：微波功率600W、煅燒時間12min和物料重量12g,仲鎢酸銨的熱分解率為90.08%。在傳統(tǒng)制備三氧化鎢的過程中,選擇煅燒溫度600℃、爐管轉(zhuǎn)速14r/min、抽氣速度3m3/min等條件,并采用合理的煅燒溫度制度,可以制備出粒度細(xì)、均勻的三氧化鎢；仲鎢酸銨在常規(guī)條件下的熱分解過程分為四個階段：脫除結(jié)晶水、分解成無定形氨鎢青銅(AATB)、轉(zhuǎn)變?yōu)榘辨u青銅(ATB)和分解為三氧化鎢；仲鎢酸銨在微波場中的熱分解過程也分為四個階段,通過與仲鎢酸銨常規(guī)熱分解特性的比較,可知仲鎢酸銨在微波場中熱分解反應(yīng)更劇烈,熱分解更加徹底、完全。由產(chǎn)物XRD可知熱分解得到的產(chǎn)物純度很高,雜質(zhì)少,潔凈度好,晶相的顆粒尺寸小,產(chǎn)物晶型為正交晶型；產(chǎn)物SEM表明結(jié)晶生長充分,顆粒均勻未出現(xiàn)團(tuán)聚,顆粒細(xì)小,晶形呈塊狀分布并且發(fā)育完整。
[Abstract]:The traditional calcination method of tungsten trioxide has the following disadvantages: long production time, high production cost, high energy consumption and difficult to guarantee the product quality. The microwave calcination method not only shortens the production time, reduces the production cost and energy consumption, but also obtains the product with good qualified rate. In this paper, the heating behavior of paratungstic acid in microwave field was studied by heating ammonium paratungstate in microwave heating furnace, and the effects of microwave power, material quantity and heating time on the temperature were discussed, respectively. The absorbing characteristics of ammonium paratungstate were also measured by microwave resonator method. Then, the optimum process conditions were determined by orthogonal test of many factors. The effects of calcination temperature, thermal decomposition rate, furnace tube speed and gas extraction rate on the preparation process of tungsten trioxide were investigated. At the same time, the traditional thermogravimetric analyzer was used to determine ammonium paratungstate, and the thermal decomposition characteristics of ammonium paratungstate under conventional conditions were analyzed. The microwave thermogravimetric analysis of ammonium paratungstate was carried out in a single-mode cavity microwave thermogravimetric analysis system. The thermal decomposition characteristics of ammonium paratungstate in microwave field were discussed and compared with the conventional thermal decomposition characteristics of ammonium paratungstate. Finally, the products of tungsten trioxide were characterized by XRD and SEM. The results show that ammonium paratungstate has good absorbing characteristics in microwave field of frequency 2.450GHz, and the heating of ammonium paratungstate in microwave field is proportional to microwave power and inversely proportional to the quantity of material. The material temperature increased gradually with the increase of microwave heating time, and the optimum technological conditions were determined by orthogonal optimization test: microwave power 600W, calcination time 12min and weight of material 12g. The thermal decomposition rate of ammonium paratungstate was 90.08. In the traditional preparation of tungsten trioxide, the fine and uniform tungsten trioxide can be prepared by selecting the calcination temperature of 600 鈩，

本文編號：1845735