硅酸盐多元体系中硅酸中间体聚合理论研究环境工程专业论文.docxVIP

山东科技大学硕士学位论文摘要 山东科技大学硕士学位论文 摘要 摘要 本文研究了以水玻璃和氟硅酸为原料合成硅酸的聚合反应过程，并探讨氟硅酸-水 玻璃体系的成胶规律，研究发现：体系 pH 、反应温度、外加电解质对硅酸聚合胶凝时 间有不同程度的影响。胶凝时间与体系的 pH 值有较大的关系，在反应物浓度一定的条 件下, 胶凝时间 lgt-pH 曲线成“N”字形。结果表明：当 pH2 时，随 pH 升高，硅酸 聚合速度变慢；在 pH≈7 时，聚合速度达到极大值；pH 7 时，聚合速度逐渐减小，这 种趋势随 pH 进一步增大而逐步增强。 本课题还研究了在氟硅酸催化下分解含钾岩石工艺中硅酸聚合反应的过程，是对于 低温湿法分解钾长石为代表的硅酸盐制取化工产品工艺后续产物分离利用的研究。此工 艺是在一个含有硅酸及硅酸盐类物质和 pH 值非常低的体系中进行的，硅酸的凝聚不只 是和它在溶液中的浓度有关，很重要的一个因素便是溶液的 pH 值、温度、离子强度等 因素有关。通过对硅酸中间体进行转型的初步实验，探讨了铵法转型的分解状况。本文 还在前人理论的基础上，分析实验现象和实验结果，对吸收法白炭黑聚合过程的机理作 了总结和解释，对吸收法白炭黑生产和转型有一定的理论参考价值。 另外，通过实验研究发现，硅酸聚合反应产品的性能与沉淀 pH 值有直接的关系， 在酸性条件下吸收法所得白炭黑具有低比表面积的缺点，是本课题解决的突出问题，为 了拓展产品的使用范围，本文提出了对硅酸中间体的铵法改型工艺，采用了用氟化铵与 吸收法白炭黑反应的方法；通过控制其反应过程中的 pH 值、反应时间、加氨浓度等条 件，制取出较原料白炭黑具有更高利用价值的白炭黑，对白炭黑的生产以及新工艺的研 究具有重要的指导意义。 关键词： 钾长石，硅酸凝聚，pH 值，胶凝时间，白炭黑 ABSTRACT The polymer ization process of making silicic acid up of H2SiF6 and waterglass was invest igated, the gelation process of H2SiF6-waterglass system was also studied. It was discovered that the pH value, the temperature and electrolytes had a different impact on the gelation time of H2SiF6-waterglass system . The pH value had a strong impact on the gelation time of H2SiF 6-waterglass system . For the system with consta nt reactant concentrations, the relationship between gelation time and pH value showed an “N” shape curve . The results indicate that the polymer ization speed of silicic acid decreased as pH was increased when pH2; the polymer ization speed of silicic acid was reached ma ximum when pH ≈ 7; When pH7, the polymer ization speed of silicic acid decreased as pH was increased , and the reaction trend was strong as pH was increased. The polymer ization process of silicic acid which was ma de by decomposing potassium- bearing rocks under the condition of H2SiF 6 was invest igated, It was a study that was about the separation and utilization of the resultant of reaction with the process of decomposing potassium-bearing rocks. The process technology was reacting with exist ing s