發(fā)布時(shí)間：2018-06-02 01:09

  本文選題：超細(xì)碳酸鋇 + 均相沉淀法　； 參考：《昆明理工大學(xué)》2011年碩士論文

【摘要】：碳酸鋇是一種重要的基礎(chǔ)無機(jī)化工原料,也是最為重要的鋇鹽之一,廣泛應(yīng)用于鋇鹽、顯像管玻殼(CRT)、磁性材料、光學(xué)玻璃、顏料等產(chǎn)品的制造以及陶瓷、搪瓷、油漆、鋼鐵滲碳、冶金、橡膠等領(lǐng)域。隨著科學(xué)技術(shù)快速發(fā)展,電子化工等領(lǐng)域?qū)μ妓徜^的要求越來越高,普通工業(yè)碳酸鋇難以滿足其要求,而超細(xì)碳酸鋇具有高的介電系數(shù)、低損耗、高磁導(dǎo)率、飽和磁化強(qiáng)度等優(yōu)點(diǎn),應(yīng)用前景廣闊,成為研究的熱點(diǎn)。 本論文結(jié)合微波加熱與均相沉淀法的優(yōu)點(diǎn)提出采用微波均相沉淀法制備超細(xì)碳酸鋇粉體的新工藝,以廉價(jià)的氯化鋇(BaCl2)和氫氧化鈉(NaOH)為原料,尿素(CO(NH2)2)為均相沉淀劑,分別采用常規(guī)和微波均相沉淀法來制備超細(xì)碳酸鋇粉體,研究了Ba2+濃度、尿素含量、氫氧化鈉含量、反應(yīng)溫度和反應(yīng)時(shí)間等因素對產(chǎn)品粒度及產(chǎn)率的影響規(guī)律；并通過添加不同的晶形控制劑合成出不同形貌的超細(xì)碳酸鋇粒子；同時(shí)對常規(guī)和微波均相沉淀法制備超細(xì)碳酸鋇粉體實(shí)驗(yàn)的動力學(xué)進(jìn)行研究,并獲得了相關(guān)動力學(xué)參數(shù);利用XRD、SEM、激光粒度分析儀、差熱差重分析和BET比表面積測試等對樣品進(jìn)行了分析與表征。 結(jié)果表明：微波均相沉淀法制備超細(xì)碳酸鋇粉體的最佳的工藝條件為：反應(yīng)溫度：85℃；反應(yīng)時(shí)間：2h；Ba2+濃度：0.8mol/L; n(NaOH)=2.5n (BaCl2·2H2O); n ((NH2)2CO:n (BaCl2·2H2O)=6；得到的碳酸鋇粉體粒度分布均勻,平均粒度1.61μm,比表面積可達(dá)16.88 m2/g；檸檬酸、多聚磷酸鈉和乙二胺四乙酸的作用下,成功制備出了針狀、柱狀、花朵狀和鳥巢狀的超細(xì)碳酸鋇粉體；常規(guī)與微波均相沉淀法制備超細(xì)碳酸鋇粉體的反應(yīng)的表觀活化能分別約為98.38 KJ/mol和88.40 KJ/mol. 通過本論文的研究可知：微波均相沉淀法具有諸多優(yōu)勢,如升溫速率快,反應(yīng)速率快,產(chǎn)品質(zhì)量高等,微波均相沉淀制備超細(xì)碳酸鋇粉體的新工藝具有工藝流程簡單、成本低、生產(chǎn)周期短、清潔無污染、安全性好、產(chǎn)品質(zhì)量高等優(yōu)點(diǎn),如若將其應(yīng)用于改造傳統(tǒng)碳酸鋇生產(chǎn)工業(yè)中,對節(jié)能降耗,提高生產(chǎn)效率及產(chǎn)品價(jià)值將具有重大意義。
[Abstract]:Barium carbonate is an important basic inorganic chemical raw material and one of the most important barium salts. It is widely used in the manufacture of barium salt, CRT, magnetic material, optical glass, pigment and other products, as well as ceramics, enamel, paint, etc. Steel Carburizing, Metallurgy, Rubber and other fields. With the rapid development of science and technology, the requirements of barium carbonate are more and more high in the fields of electronics and chemical engineering, and it is difficult to meet the requirements of ordinary industrial barium carbonate, while ultrafine barium carbonate has high dielectric coefficient, low loss and high permeability. Saturation magnetization has a wide application prospect and has become a hot research topic. Combining the advantages of microwave heating and homogeneous precipitation method, a new technology of preparing ultrafine barium carbonate powder by microwave homogeneous precipitation method was proposed in this paper. The raw materials were cheap barium chloride (BaCl2) and sodium hydroxide (NaOH), and urea (COC) NH2 (2) was used as homogeneous precipitating agent. Ultrafine barium carbonate powders were prepared by conventional and microwave homogeneous precipitation methods. The effects of Ba2 concentration, urea content, sodium hydroxide content, reaction temperature and reaction time on product size and yield were studied. The ultrafine barium carbonate particles with different morphology were synthesized by adding different crystal shape control agents, and the kinetics of preparing ultrafine barium carbonate powder by conventional and microwave homogeneous precipitation method was studied, and the relevant kinetic parameters were obtained. The samples were analyzed and characterized by XRD-SEM, laser particle size analyzer, differential thermogravimetric analysis and BET specific surface area measurement. The results show that the optimum conditions for the preparation of ultrafine barium carbonate powder by microwave homogeneous precipitation are as follows: reaction temperature: 85 鈩，

本文編號：1966599