高钛渣制备钛硅复合催化剂中钛的形态调控与水解控速的关键机制
发布时间：2018-12-29 20:17
【摘要】：针对我国高钛渣物相复杂难处置又具有多种可利用资源的矛盾,基于高钛渣制备钛硅复合催化剂的资源化利用的构想,以攀枝花西昌地区的高钛渣为对象,通过高钛渣热力学转化的物理化学过程模拟、酸碱实际体系中高钛渣转化行为分析等手段,研究了高钛渣在不同介质与条件下形成Ti O2-Si O2复合催化剂的转化途径与其影响机制。同时,利用水热成矿过程晶体成核-生长原理,通过环境介质与络合剂的优化,复合催化材料催化性能评价与过程分析等方法,深入探讨了高钛渣制备钛硅复合材料中Ti、Si的转化与复合过程,讨论了复合材料形成过程中Ti形态调控与水解控速关键机制。研究结果表明:1.Na OH在低温(150 o C以下)条件下能生成碱性玄武石。氢氟酸、硫酸和硝酸只与透辉石和玄武石发生反应。氢氟酸能提取高钛渣中14%~93%的硅,在该溶液中金属离子易生成氟化物。硫酸中金属离子主要以离子形式存在于液相,部分Ca2+与SO42+形成Ca SO4。2.盐酸完全分解高钛渣,得到含Ti O2的产品。高钛渣盐酸水热浸提后的产物中Ti O2的晶相与Cl-离子浓度和硅含量有关。Cl-离子浓度在1 mol/L左右生成锐钛矿型Ti O2,在2 mol/L以上则为金红石型。无定形二氧化硅促进Ti O2由锐钛矿型向金红石型转变。添加的氢氟酸在处理高钛渣过程中,起到调控钛硅比和抑制金红石型Ti O2生成的作用。EDTA对Mg、Fe、Ti、Si的沉淀有明显的缓释作用,会导致高钛渣中的钛向金红石相转化。3.高钛渣经盐酸分解后,钛与氯离子结合产生Ti Cl4,在含有HF的溶液中先生成Ti F4,并发生快速水解生成二氧化钛。EDTA能直接与钛离子络合,减缓酸性水热条件下钛离子的水解。合成的材料对染料罗丹明B具有一定的吸附和光催化性能。HF0.6光催化性能最好,加入EDTA合成的材料吸附性能最佳。通过盐酸水热处理的调控形成和水解控速,高钛渣可以制备具有一定光催化效果的钛硅复合材料。论文研究结果为高钛渣资源化利用奠定了实验基础和理论依据。
[Abstract]:In view of the contradiction of complex and difficult phase disposal of high titanium slag in China and of many available resources, based on the conception of resource utilization of Ti-Si composite catalyst prepared from high titanium slag, the high titanium slag in Xichang area of Panzhihua was taken as the object. Through the physical and chemical simulation of thermodynamics transformation of high titanium slag and the analysis of transformation behavior of high titanium slag in acid-base actual system, The conversion pathway and its influence mechanism of high titanium slag to form Ti O2-Si O 2 composite catalyst in different media and conditions were studied. At the same time, based on the principle of crystal nucleation and growth during hydrothermal mineralization, through the optimization of environment medium and complexing agent, the evaluation of catalytic performance and process analysis of composite catalytic materials, the preparation of Ti, in titanium-silicon composites with high titanium slag was discussed. The transformation and composite process of Si were discussed. The key mechanisms of Ti morphology regulation and hydrolysis speed control in the process of composite formation were discussed. The results show that 1.Na OH can produce alkaline Black Tortoise at low temperature (below 150oC). Hydrofluoric acid, sulfuric acid and nitric acid only react with diopside and Black Tortoise. Hydrofluoric acid can extract 93% silicon from high titanium slag, and metal ions can easily form fluoride in this solution. Metal ions in sulfuric acid mainly exist in liquid phase in the form of ions, and some Ca2 and SO42 form Ca SO4.2.. The high titanium slag was completely decomposed with hydrochloric acid and the product containing Ti O 2 was obtained. The crystalline phase of Ti O 2 in the hydrochloric acid extracted from high titanium residue is related to the concentration of Cl- ion and the content of silicon. The Cl- ion concentration is about 1 mol/L to form anatase Ti O 2, and more than 2 mol/L is rutile. Amorphous silica promotes the transition of Ti O 2 from anatase to rutile. The addition of hydrofluoric acid can regulate the ratio of titanium to silicon and inhibit the formation of rutile Ti O 2 in the treatment of high titanium slag. EDTA has obvious slow release effect on the precipitation of Mg,Fe,Ti,Si. It will result in the transformation of titanium from high titanium slag to rutile phase. 3. After decomposition of high titanium slag by hydrochloric acid, titanium binds with chloride ion to form Ti Cl4, into Ti F4 in solution containing HF, and then rapidly hydrolyzes to form titanium dioxide. EDTA can directly complexate with titanium ion and slow down the hydrolysis of titanium ion under acidic hydrothermal conditions. The synthesized material has certain adsorption and photocatalytic properties to dye Rhodamine B. HF0.6 has the best photocatalytic activity, and the material synthesized with EDTA has the best adsorption performance. By controlling the formation and hydrolysis speed of hydrochloric acid hydrothermal treatment, titanium silicon composites with certain photocatalytic effect can be prepared by high titanium slag. The results of this paper lay an experimental and theoretical basis for the utilization of high titanium slag.
【学位授予单位】：上海大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TQ426;X756
本文编号：2395338
[Abstract]:In view of the contradiction of complex and difficult phase disposal of high titanium slag in China and of many available resources, based on the conception of resource utilization of Ti-Si composite catalyst prepared from high titanium slag, the high titanium slag in Xichang area of Panzhihua was taken as the object. Through the physical and chemical simulation of thermodynamics transformation of high titanium slag and the analysis of transformation behavior of high titanium slag in acid-base actual system, The conversion pathway and its influence mechanism of high titanium slag to form Ti O2-Si O 2 composite catalyst in different media and conditions were studied. At the same time, based on the principle of crystal nucleation and growth during hydrothermal mineralization, through the optimization of environment medium and complexing agent, the evaluation of catalytic performance and process analysis of composite catalytic materials, the preparation of Ti, in titanium-silicon composites with high titanium slag was discussed. The transformation and composite process of Si were discussed. The key mechanisms of Ti morphology regulation and hydrolysis speed control in the process of composite formation were discussed. The results show that 1.Na OH can produce alkaline Black Tortoise at low temperature (below 150oC). Hydrofluoric acid, sulfuric acid and nitric acid only react with diopside and Black Tortoise. Hydrofluoric acid can extract 93% silicon from high titanium slag, and metal ions can easily form fluoride in this solution. Metal ions in sulfuric acid mainly exist in liquid phase in the form of ions, and some Ca2 and SO42 form Ca SO4.2.. The high titanium slag was completely decomposed with hydrochloric acid and the product containing Ti O 2 was obtained. The crystalline phase of Ti O 2 in the hydrochloric acid extracted from high titanium residue is related to the concentration of Cl- ion and the content of silicon. The Cl- ion concentration is about 1 mol/L to form anatase Ti O 2, and more than 2 mol/L is rutile. Amorphous silica promotes the transition of Ti O 2 from anatase to rutile. The addition of hydrofluoric acid can regulate the ratio of titanium to silicon and inhibit the formation of rutile Ti O 2 in the treatment of high titanium slag. EDTA has obvious slow release effect on the precipitation of Mg,Fe,Ti,Si. It will result in the transformation of titanium from high titanium slag to rutile phase. 3. After decomposition of high titanium slag by hydrochloric acid, titanium binds with chloride ion to form Ti Cl4, into Ti F4 in solution containing HF, and then rapidly hydrolyzes to form titanium dioxide. EDTA can directly complexate with titanium ion and slow down the hydrolysis of titanium ion under acidic hydrothermal conditions. The synthesized material has certain adsorption and photocatalytic properties to dye Rhodamine B. HF0.6 has the best photocatalytic activity, and the material synthesized with EDTA has the best adsorption performance. By controlling the formation and hydrolysis speed of hydrochloric acid hydrothermal treatment, titanium silicon composites with certain photocatalytic effect can be prepared by high titanium slag. The results of this paper lay an experimental and theoretical basis for the utilization of high titanium slag.
【学位授予单位】：上海大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TQ426;X756
【参考文献】
相关期刊论文 前2条
1 石妍;杨华美;王迎春;杨华全;李家正;;高钛矿渣对水泥基复合材料性能的影响[J];新型建筑材料;2009年09期
2 朱洪波;王培铭;张继东;王汴文;;利用攀钢提钛高炉矿渣制砖[J];新型建筑材料;2010年06期
，本文编号：2395338
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