Application of ozone decomposition catalyst in glove box

In the closed experimental environment of the glove box, when it comes to processes such as ultraviolet curing and plasma treatment, the generation of ozone is inevitable. Excessive ozone will not only damage the samples and equipment in the box, but also pose a safety hazard. Ozone decomposition catalysts have become a key technology to ensure the stable operation of the glove box due to their efficient decomposition characteristics.

The space in the glove box is compact, the process temperature is mostly maintained at room temperature to 80°C, and it is often accompanied by impurities such as organic solvent vapor and metal dust, which puts strict requirements on ozone decomposition catalysts. The copper-manganese composite catalyst can achieve efficient decomposition at low temperatures due to its rich active sites brought by its nano-scale porous structure, and the decomposition efficiency of ozone can reach more than 95% in the range of 20-60°C. The mechanical strength is improved by loading the γ-Al₂O₃ carrier, and the anti-interference is enhanced by doping rare earth elements, so that it can adapt well to the glove box environment.

The application of ozone decomposition catalysts in the glove box requires a carefully designed integrated solution. The catalyst device can choose built-in or external circulation mode. The built-in type encapsulates the honeycomb catalyst in a stainless steel mesh cylinder and fixes it near the gas circulation fan, using the airflow in the box to drive the ozone to contact the catalyst; the external circulation type sets an independent catalytic unit outside the box, forming a closed loop with the box through a pipeline. In either case, it is necessary to cooperate with the pretreatment system, use the filter element to filter metal dust, the molecular sieve to control humidity, and the activated carbon to adsorb organic vapor to prevent impurities from affecting the performance of the catalyst.

During operation, the maintenance and performance optimization of the catalyst are crucial. The ultraviolet spectrophotometer in the glove box monitors the ozone concentration in real time. When the catalyst decomposition efficiency is lower than 85%, the regeneration program is started. The adsorbed organic matter is decomposed and desorbed by increasing the temperature in the box or blowing with hot air offline. Under normal conventional processes, regeneration is performed every 3-6 months. When frequently exposed to high concentrations of ozone or impurity gases, the regeneration cycle needs to be shortened. After 1-2 years of cumulative use, even after regeneration, the activity of the catalyst is difficult to recover and needs to be replaced in time. When replacing, it must be operated under the protection of inert gas to avoid residual active oxygen species triggering reactions. At the same time, the catalytic unit needs to be linked with the inert gas replenishment system to control the oxygen concentration to prevent it from exceeding the upper limit allowed by the process.

Taking the preparation of lithium-ion battery positive electrode materials as an example, the ozone cleaning process in the glove box produces about 80ppm of ozone. After using the built-in copper-manganese composite catalyst device, the ozone concentration can be reduced to below 0.1ppm within 10 minutes, and it can maintain efficient operation for 6 months. In the field of semiconductor packaging, the external circulating catalytic system cooperates with the precision process of the glove box to effectively ensure the oxygen-free and water-free environment required for chip packaging. The deep integration of ozone decomposition catalyst and glove box system not only eliminates the harm of ozone, but also builds a safety barrier for high-precision experiments and production, and promotes technological progress in cutting-edge science and technology fields.