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This work aimed to study the kinetics of thermal and catalytic pyrolysis using Ti-MCM-41 as catalyst in order to assess the catalytic pyrolysis efficiency compared to thermal pyrolysis of elephant grass. Ti-MCM-41 molecular sieve was synthesized by hydrothermal method from hydrogel with the following molar composition:1.00 CTMABr: 4.00 SiO 2 :X TiO 2 : 1 + X Na 2 O: 200.00 H 2 O, whichstructure template used was cetyltrimethylammonium bromide (CTMABr). The materials synthesized were characterized by X-ray diffraction, IR spectroscopy, thermogravimetric analysis and specific area by the BET method, for subsequent application in the biomass pyrolysis process. The kinetic models proposed by Vyazovkin and Flynn-Wall were used to determine the apparent activation energy involved in the thermal and catalytic pyrolysis of elephant grass and the results showed that the catalyst used was effective in reducing the apparent activation energy involved in the thermal decomposition of elephant grass.

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Biomass has attracted considerable attention as energy, economic, and environmental asset, as result of its abundance and range of properties. The use of mesoporous catalysts during fast pyrolysis has been a highly important route to improve efficiency as well adding value to biomass. The addition of titanium to molecular sieves increases the efficiency of the pyrolysis reaction by improving production and selectivity of products of interest. This study aims at analyzing the catalytic pyrolysis products of elephant grass using titanium catalysts prepared at different Si/Ti molar ratios, i.e., 25 and 50. The material was supported on MCM-41 for the catalytic pyrolysis of biomass. The biomass pyrolysis reactions were performed in a micropyrolyzer coupled to a GC/MS analyzer. The Ti-MCM-41 samples were characterized by XRD, BET-specific area, and UV-visible. The distribution of pyrolysis products depended on process parameters such as temperature and catalyst type. The highest yield for hydrocarbon production, such as styrene, benzene, methylbenzene, and naphthalene, was observed at 600 °C using Si/Ti equal to 50.

The CO2 adsorption technology using solid adsorbent shas been considered as a promising approach to reduce CO2 emissions. Therefore, research has been developed to obtain efficient and economically viable adsorbents. The mesoporous materials of the MCM-41 type are among the candidates for effective adsorbents as a result of easy synthesis and structure which favors the flow of gas. The aim of this study was to improve the synthesis of MCM-41 using mixtures of cationic surfactants and apply in CO2 capture. The cationic surfactants used weretetradecyltrimetylammonium bromide (TTMABr - C17H38NBr) and cetyltrimethylammonium bromide (C19H42NBr) and their mixture in a ratio of 1:1. The CO2 adsorption was investigated using the gravimetric method at 298K and pressure varying up to 40 bar. The resulting materials, C17, C19 and C17C19, were characterized by XRD, FTIR, TG and SEM. The results revealed significant differences in the structure of the materials and amount of of CO2 adsorbed.