Effect of pretreatment methods and doping amount of Enteromorpha on the exhaust purification performance of perovskite catalysts used in underground diesel vehicles

In this work, the processing and amount of Enteromorpha was examined in terms of its use as a dopant of a perovskite catalyst used in the removal of pollutants from diesel vehicle exhaust gas. First, the Enteromorpha was pretreated either by grinding it or by subjecting it to high temperature pyrolysis. The pretreated Enteromorpha was then used to dope perovskite catalyst La0.8Ce0.2Co0.4Mn0.6O3 via a sol gel preparation method. A combination of materials characterization techniques and activity evaluations were used to examine the effects of the Enteromorpha pretreatment methods and amount of doping on the reduction and oxidation performance of the doped perovskite catalysts. The results showed that the doping of Enteromorpha led to the inclusion of Fe ions in the catalyst, resulting in an increase in grain size, a decrease in the lattice constant, and a significant increase in oxygen vacancies in the sample, which promoted molecular activation. In terms of the oxidation of particulate matter, the catalysts doped with Enteromorpha treated with high-temperature pyrolysis was superior to the catalyst treated with Enteromorpha that was only treated by the natural grinding method. The maximum purification efficiency for NO of the perovskite catalyst doped with Enteromorpha treated with high-temperature pyrolysis was >60%. For the different pretreatment methods, the oxidation and reduction performance of the doped perovskite catalysts was highest when the amount of Enteromorpha added to the perovskite catalyst was 0.2 g. Additional doping of Enteromorpha into the perovskite catalyst was not conducive to the purification of diesel vehicle exhaust gas by the doped catalysts. This paper can provide an engineering strategy for improving the exhaust purification performance of various types of catalysts, as well as a new approach for catalyst modification and treatment methods.