Extração de sílica e celulose a partir da casca de arroz

• Autor(a) principal: Simundi, Felipe Soeiro Meyrer
• Data de Publicação: 2017
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da PUC_RS
• Texto Completo: http://tede2.pucrs.br/tede2/handle/tede/7538
• topic: Casca de Arroz; Sílica; Celulose; ENGENHARIAS

In this work, the extraction of cellulose and silica from rice hulls, an important agricultural residue, was studied, since both domestic and international production generates billions of tons per year. Therefore, it is a rice husk and a source of agricultural document cellulose, in addition to being rich in amorphous silica, these materials can find applications as consumers in polymers, supports for catalysts and ionic liquids as well as capture and separation processes from Gases, in addition to its conventional applications in paper production reservoirs and civil construction. Different conditions of silica and cellulose extraction were tested for a high degree of yield and purity. The method tested for silica extraction proved to be quite efficient in extracting from the rice hull a silica of purity greater than 95% and about 270 m2 / g of specific surface area. Among the acids tested, which are shown to be more efficient in the case of acetic acid, are successful, are more efficient, and have a better yield. As for cellulose, the process was divided into three stages and had a yield of 30% equivalent to the expected cellulose rate in a rice hull, but the product obtained varied depending on the bleaching process. Although the process with the hydrogen powder and acetic acid has generated a product with better macroscopic appearance the process, use the improved measurement method when better samples when not detected in the scanning electron microscope.