Effect of Fe, Cu, and Li cations to modifyZSM-5 zeolite toimprove catalytic converter performance during cold-startemission

Automotive catalyst is used to eliminate pollutants from engines. One of the most crucial problems about automotive catalysts is cold start, which can be solved by using various approaches and the best way is using a suitable absorbent. In our study, modification of zeolite in catalytic converters during cold start is discussed. ZSM-5 zeolite was impregnated and modified with base metals, such as Cu, Fe, and Li,60 gr of the metal to 130 gr of ZSM-5; then it was checked by BET, TPD and performance tests. Among these metals, Cu-ZSM-5 (60-130) zeolite had the highest desorption rate at high temperatures, and also the highest conversion rate in terms of performance for the conversion of the three pollutants NOX, HC and CO. with the FESEM test, it was well recognized that there is a good distribution and no aggregateshrinkage for this zeolite. Finally, by studying the emissions test of the catalyst prepared with ZSM-5 and Cu-ZSM-5 (60-130) zeolite, it was found that the amount of emissions, especially NOX, was substantially decreased.

Keywords:

Catalytic converters , modified zeolite , absorbent , catalyst activity , emission test