Photocatalytic reduction of CO2

Abstract

The concentration of CO2 in the atmosphere is nowadays a worldwide problem, because is one of the gases contributing to global warming. It is a fact that CO2 is increasing every time more and more in the atmosphere due to several industrial activities and the own carbon cycle. From this point of view, it is wanted to suggest the photoreduction of CO2 in water with natural zeolites (in this case clinoptilolite) as a possible solution. In this research two different types zeolites were tested, the difference was the particle size, and also two different modifications of them. In order to catch as much CO2 as possible it was experimented with the solubility of CO2 in water and to convert as much as CO2 into organic compounds several photoreduction were developed. The results show that it is possible to convert CO2 into organic matter performing a photoreduction with clinoptilolite. It was found out that the best conditions for a more efficient photoreduction are with 0,1 g of zeolites as catalyst, although there is not a big difference between the particle size of zeolites, the better working photocatalyst was the zeolites with particle size less than 0,25 mm. About the temperature of the photoreduction can be achieved same results with cold and warm water, but depends on the speed wanted for the reaction, cold reaction are slower than warm reactions.