CRT玻璃高温自蔓延反应过程中铅的挥发及纳米晶化规律研究

Lead Evaporation from CRT Glass and Nanocrystallization Mechanism in the High-temperature Self-propagating Process

研究了废旧阴极射线管(CRT)玻璃高温自蔓延技术制备纳米PbO的基本过程和规律,考察了Fe2O3-Mg-CRT自蔓延体系的最高燃烧温度及燃烧波传播速率,探索了不同CRT玻璃配比对铅提取率、物相组成以及微观形貌的影响,分析了高温自蔓延反应过程中铅的挥发及纳米晶化规律,并对CRT高温自蔓延反应过程中的热力学机理和铅的挥发机制进行了初步研究.实验结果表明,随着CRT玻璃加入量的增加,高温自蔓延反应的最高燃烧温度、燃烧波传播速率和产物纳米PbO颗粒的团聚程度均呈减小的趋势.当CRT玻璃加入量为40wt%,CRT中铅的回收率约为93%,产物为球状的PbO纳米颗粒,粒径40～50 nm.本研究可以为CRT高温自蔓延处理技术的工业化应用提供一定的理论依据和数据基础.

Lead evaporation and recovery of nanoparticle materials from waste cathode-ray tube（CRT） glass using the self-propagating high-temperature synthesis（SHS） method was investigated.The reaction temperature and combustion velocity of the mixture of Fe2O3-Mg-CRT in the SHS process were studied in detail.Then the lead extraction ratio,phase compositions as well as the micromorphology of extracted PbO nanoparticles were examined.The thermodynamics of lead evaporation and nanocrystallization mechanism were also analyzed.It can be found that the SHS reaction temperature and combustion velocity decrease with increasing CRT glass content,and the addition of CRT glass as a diluent can be used to control the SHS lead extraction behavior to obtain PbO nanoparticles with good desperation and morphology.With 40wt% CRT glass addition,about 93% of lead can be recovered from CRT glass as nano-sized PbO with high purity.The collected PbO nanoparticles are almost spherical in shape with particle sizes ranging from 40 nm to 50 nm,which are mainly from the volatilization and rapid condensation during the SHS process. The study indicates a novel method to recycle and reuse waste CRT glass.