摘要
钒钛系脱硝催化剂由于长期运行在火电厂高温烟气中,活性会随着运行时间的延长而逐渐下降,使用寿命一般为3~4 a。其中约60%的脱硝催化剂受物理结构破损、机械性能下降等因素影响而不具备再生价值,需作报废处理。对其中有价金属元素的提取是实现报废脱硝催化剂高效资源化利用的重要方式。本文针对无机与有机混合酸溶液回收废脱硝催化剂中钒的过程,分析了浸出过程中的动力学模型,采用宏观动力学的研究方法,探究了浸出过程的控制类型。结果显示,硫酸-草酸混酸浸出废脱硝催化剂中钒的过程为典型的液-固相非催化反应类型,动力学模型为未反应核缩减模型。浸出过程中钒的动力学控制类型为表面化学反应控制,可用动力学方程来拟合,拟合直线的线性相关系数大于0.98,具有很好的线性相关性,该过程的反应活化能为4.53 kJ/mol。
Due to long-term operation in high-temperature flue gas of thermal power plants,the activity of vanadium titanium-based denitration catalyst gradually decreases with the extension of operating time,and their service life is generally 3~4 years.About 60%of these denitration catalyst are affected by factors such as physical structure damage and mechanical performance degradation,and therefore do not have regeneration value and need to be scrapped.Extracting valuable metal elements from them is an important way to achieve efficient resource utilization of spent denitration catalyst.This study proposes a technical route for recovering vanadium from spent denitration catalyst using inorganic-organic combined solvent.The kinetic model during the leaching process was analyzed,and the entire process of recovering vanadium and support from spent denitration catalyst was formed.Kinetic analysis was studied on the leaching vanadium based on the optimal process conditions of sulfuric acid-oxalic acid combined solvent.The research method of macroscopic dynamics was adopted to explore the chemical reaction control of the leaching process.The results showed that the process of leaching vanadium from spent denitration catalyst with sulfuric acid-oxalic acid combined solvent was a typical liquid-solid non-catalytic reaction,and the kinetic model was an unreacted core reduction model.The kinetic control type of vanadium during the leaching process is surface chemical reaction control,which can be fitted by the kinetic equation.The linear correlation coefficient of the fitted line is greater than 0.98 and the activation energy of this process is 4.53 kJ/mol.
作者
李扬
李杰
程文婷
LI Yang;LI Jie;CHENG Wenting(Longking-Coalogix Environmental Protection Technology(Shanghai)Co.,Ltd.,Shanghai 200331,China;Jiangsu Longking-Coalogix Environmental Protection Technology Co.,Ltd.,Yancheng 224051,Jiangsu China;State Environmental Protection Key Laboratory of Efficient Utilization Technology of Coal Waste Resources(Shanxi University),Taiyuan 030006,Shanxi China)
出处
《电力科技与环保》
2024年第4期427-433,共7页
Electric Power Technology and Environmental Protection
基金
国家自然科学基金项目(22208198)
国家重点研发计划项目(2022YFC3901305)
国家节能低碳材料生产应用示范平台项目(TC220H06N)。
关键词
混合酸浸出
废脱硝催化剂
动力学研究
mixed acid synergistic
spent deNO_(x)catalyst
kinetics of vanadium leaching
