Banca de QUALIFICAÇÃO: ELIANE DE AQUINO LIMA BRANDÃO

MMOBILIZATION OF COMMERCIAL CELLULASES ON MAGNETIC NANOPARTICLES AND APPLICATION IN THE HYDROLYSIS OF PRE-TREATED SUGARCANE BAGASSE FOR THE PRODUCTION OF 2G ETHANOL

cellulases, enzyme immobilization, mixed magnetic nanoparticles, reuse of lignin, 2G ethanol.

Due to growing concerns about climate change resulting from greenhouse gas emissions, the search for sustainable energy sources has been one of the main focuses of research in the 21st century. The production of ethanol from lignocellulosic biomass, usually called second generation ethanol (2G ethanol), obtained from agricultural residues, such as sugarcane bagasse, acerola peels, rice straw, among others, is considered an ecologically correct and economically viable resource. Cellulases play an important role in the hydrolysis of cellulose, acting in biotechnological processes, in the areas of biofuels, cellulose and paper, and the textile industry. In the process of converting lignocellulosic biomass into 2G ethanol, the step that offers the greatest economic impact is enzymatic hydrolysis. At this stage, there are some challenges that need to be overcome, such as issues of thermal stability and extreme pH of the enzyme in its soluble form, reusability and cost. Immobilization is a strategy that consists of fixing enzymes on solid supports, establishing chemical bonds or physical interactions between the enzymes and an insoluble support in order to generate a heterogeneous biocatalyst. The immobilization of enzymes on nanomaterials, such as magnetic nanoparticles (NPMs), produces easily recoverable and reusable biocatalysts using a magnetic field. Furthermore, NPMs have low toxicity and their groups can be easily modified, using, for example, a byproduct of biomass pretreatment, lignin. In this context, this research aims to boost innovations in the area of 2G ethanol production through the immobilization of commercial cellulolytic cocktails in mixed copper and nickel magnetic nanoparticles covered with lignin, applying the biocatalysts produced in the hydrolysis of sugarcane bagasse pre-treated for the production of 2G ethanol.