MICROWAVE-ASSISTED GREEN SYNTHESIS FOR OBTAINING ZEOLITE ZSM-5 APPLIED TO CATALYTIC PYROLYSIS OF RESIDUAL FRYING OIL AND BEEF TALLOW
Biofuels; Zeolite Synthesis; ZSM-5; HZSM-5; Ni/HZSM-5; residual frying oil; beef tallow; catalytic pyrolysis.
The current energy transition and the promotion of clean and renewable energy sources have led to the search for increasingly efficient conversion processes, where catalysts represent a fundamental role in the production of several high value-added products, such as biofuels. Zeolitic materials are among the solid acid catalysts widely explored in fuel refining and the petrochemical industry due to their high activity, thermal stability and strong acidity. In this class, the ZSM-5 zeolite stands out, which has a porous structure, which gives it molecular sieve characteristics, capable of selectively adsorbing molecules. The hydrothermal process is the most commonly used for the synthesis of this zeolitic catalyst, where extremely long crystallization times are reported, in addition to the use of organic templates and seeds to obtain the crystalline structure. Therefore, this work proposed an innovative method for the synthesis of ZSM-5 zeolite, carried out without the use of seeds or organic templates, through a microwave-assisted hydrothermal process, which allowed the formation of the crystalline structure in a shorter period than previously reported. Furthermore, this invention patent proposed here an efficient alternative that significantly reduces the crystallization time compared to traditional methods, providing savings in time, reagents, energy and total costs. Subsequently, the catalyst was also explored with acid proton form and impregnated with 15% nickel (15% w/w). The samples were characterized, allowing the confirmation of the formation of the ZSM-5 crystalline structure, its composition, proportion, microporosity and acidity. Furthermore, the protonated and impregnated samples were applied in the thermochemical pyrolysis route, using biomass from waste frying oil and beef tallow to evaluate its efficiency, as well as the pyrolytic products generated.