三氯氧钒催化氧化制备高纯五氧化二钒的反应机理及优化调控

High purity vanadium pentoxide is one of the most promising vanadium products with high added-values. This project presents a novel process for its efficient and clean production from metallurgical grade vanadium materials by carbochlorination – distillation – catalytic oxidation. Chlorine gas can be generated from the catalytic oxidation of vanadium oxychloride and recycled for the carbochlorination. The catalytic oxidation is too complex to be further optimized, due to its coupling of gas phase hydrolysis of vanadium oxychloride and catalytic oxidation of hydrogen chloride. Combining with quantum chemistry calculation and experimental methods, therefore, the reaction mechanisms of gas phase hydrolysis of vanadium oxychloride and catalytic oxidation of hydrogen chloride, and their coupling effects are carefully studied. The methods of the coupling control of reaction rate and product structure during the gas phase hydrolysis, the strengthening of catalytic oxidation of hydrogen chloride by catalyst structure optimization and the rate matching of the two main reactions are researched and developed. And the optimal regulation of catalytic oxidation process is established from process experiments based on above research results. The novel method of catalytic oxidation of vanadium oxychloride for preparation of high purity vanadium pentoxide with new theory will be obtained. It is hope that the present application can provide scientific support for the industrial application of the novel chlorination process for the efficient and clean production of high purity vanadium pentoxide.

高纯五氧化二钒是最具应用前景的高附加值钒制品之一。为了实现其高效清洁生产，项目提出工业级钒原料配碳氯化—精馏提纯—催化氧化同步实现高纯五氧化二钒制备和氯气再生循环的创新技术路线。其核心工艺—三氯氧钒催化氧化因复杂地耦合了三氯氧钒气相水解和氯化氢催化氧化，进一步优化调控面临挑战。对此，项目拟结合理论计算和实验研究手段深入研究三氯氧钒气相水解和氯化氢催化氧化的反应机理及两者耦合作用规律，研究实现三氯氧钒气相水解反应速率与产物结构的耦合调控、催化剂结构调控强化氯化氢催化氧化以及气相水解与氯化氢催化氧化的反应速率优化匹配，进而构建催化氧化工艺优化调控机制，形成三氯氧钒催化氧化制备高纯五氧化二钒的新理论新方法，为高效清洁氯化法高纯五氧化二钒新技术的工业化应用提供坚实的基础理论支撑。

高纯五氧化二钒是最具应用前景的高附加值钒制品之一。为了实现其高效清洁生产，项目提出工业级钒原料配碳氯化—精馏提纯—催化氧化同步实现高纯五氧化二钒制备和氯气再生循环的创新技术路线。针对其核心工艺—三氯氧钒催化氧化优化调控难题，项目结合热力学、量子理论计算和实验研究手段深入研究三氯氧钒气相水解和氯化氢催化氧化的反应机理及两者耦合作用规律，在研究建立含精制尾渣选择性氯化制备三氯氧钒基础上，开展水解和氧化耦合过程研究，揭示了引入水蒸气对三氯氧钒氧化动力学的强化机制，并结合沉积产物形貌规律，建立三氯氧钒催化氧化强化机制。进一步地，针对水解反应导致氯浸染于五氧化二钒产物中的问题，开展产物焙烧脱氯机制研究，建立了氢还原-氧化深度脱氯的新方法，获得了4N以上纯度的高纯五氧化二钒。从而形成三氯氧钒催化氧化制备高纯五氧化二钒的新理论新方法，为高效清洁氯化法高纯五氧化二钒新技术的工业化应用提供坚实的基础理论支撑。