Performance And Safety Analysis Of CO Oxidation At Low Temperature By Mesoporous Nanocomposite Metal Oxides

Carbon monoxide?CO?is harmful to blood and nerves produced by any incomplete combustion process.In recent years,with the popularity of water heaters,the use of gas water heaters in winter has caused more and more CO poisoning.Among many methods for eliminating CO,catalytic combustion technology is considered to be the most valuable CO purification technology due to its advantages of environmental protection,low light-off temperature,and high purification efficiency.Non-precious metal catalysts are cheap,but the catalytic light-off temperature is high,so the development of low-temperature and efficient catalyst technology has become the focus of research.In this paper,copper-manganese oxide catalysts were firstly prepared by co-precipitation method.The effects of molar ratio of copper to manganese and calcination temperature on the catalyst composition and CO oxidation activity were systematically investigated by means of XRD,BET and TPR.The results showed that:When Cu/Mn=1/2,the calcination temperature is 400°C,the catalyst activity is the highest.At the CO concentration of 500ppm,the space velocity is 7165h^-1,70°C,CO can be completely converted,which is attributed to the catalyst.There are a lot of CuMn₂O₄spinel,Mn⁴⁺and free CuO.Under high temperature calcination,the crystallinity of copper-manganese oxide catalyst is high,the amount of amorphous morphologies decreases,the grain size increases,the specific surface area decreases seriously,and the catalyst is almost inactivated.When Cu/Mn=1/2,the calcination temperature at 600°C,The CO conversion was only 43%at 190°C.In order to improve the high-temperature anti-aging ability of copper-manganese oxide,the components were optimized.The effect of potassium doping by copper-manganese oxide on the performance of the catalyst and the effect of CO oxidation activity were investigated.The results showed that the potassium-doped copper-manganese oxide catalyst calcined at 400°C,the specific surface of the catalyst was decreased due to the addition of potassium ions,and the activity of the catalyst was decreased.After 4 h at 600°C,potassium ions entered the copper and manganese.The oxide lattice restrains the growth of the crystal lattice and reduces the crystal size of the catalyst.Compared with the activity of the copper-manganese oxide catalyst synthesized under the same conditions,the aging resistance is improved.The electrostatic interaction between ions in the deposition deposition method was applied to the preparation of mesoporous nano-copper-manganese oxide catalysts by KIT-6molecular sieve.The structure of the catalyst was optimized,and the influence of the catalyst on the CO oxidation performance was investigated.The results show that the specific surface area of the CM-kit catalyst obtained by the improved precipitation precipitation method assisted KIT-6 molecular sieve is higher than that of the catalyst obtained by using KIT-6 only as the template agent,and the optimized specific surface area of the copper-manganese oxide is increased,and the catalytic activity is improved.Improvement,low temperature activity is very good,in the CO concentration of500ppm,space velocity of 7165h^-1 conditions,60 degrees can completely oxidize CO,but the anti-aging ability is not,so can be applied in the temperature range between60⁴00°C Place.KCM-kit catalyst has good low-temperature oxidation activity.Although the temperature of completely oxidizing CO at low temperature is 10°C higher than that of CM-kit,it has a wider application range,and the temperature range is 70⁴00°C,120⁶00°C,160⁸00°C can maintain good low temperature activity.The safety analysis of the raw materials involved in the experiment,the catalyst preparation process and the CO oxidation reaction were carried out.The catalyst achieves a complete conversion of CO at a lower temperature and will not affect human health and meet the design hygiene standards of industrial enterprises.