To evaluate the physico-mechanical and quality properties of the cellulose pulp of two new bleaching sequences

• Grant number: 19/05717-7
• Support Opportunities: Regular Research Grants
• Start date: July 01, 2019
• End date: June 30, 2021
• Field of knowledge: Agronomical Sciences - Forestry Resources and Forestry Engineering - Technology and Use of Forest Products
• Principal Investigator: Gustavo Ventorim
• Grantee: Gustavo Ventorim
• Host Institution: Universidade Estadual Paulista (UNESP). Campus Experimental de Itapeva. Itapeva , SP, Brazil

Abstract

Following ideal bleaching, the removal of undesirable components present in the pulp, such as lignin and hexenuronic acids, is efficient, but at a low cost in the process. As this removal occurs differently, the sequence used should contain suitable ways for removal of these two chemical compounds. The high temperature acid hydrolysis (AHT) stage presents adequate conditions for the selective removal of hexenuronic acids, although its acidic pH is not ideal for the removal of lignin. Therefore, it is interesting to use a high temperature alkaline extraction (EHT) in the bleaching sequence in order to obtain greater efficiency in lignin removal, since it is more soluble in alkaline medium. The objective of this project is to evaluate the physico-mechanical properties of the bleaching sequences, which have an alkaline extraction under the same operating conditions (120 min / 95ºC) as a high temperature acid hydrolysis. This study uses pre-delignified eucalyptus kraft pulp with oxygen from a pulp company. With this pulp different bleaching sequences ECF (Elemental Chlorine Free), OD (E + P) DP, OAHTDP, OAHTEHTDP were performed. The results of brightness, viscosity, reagent consumption and physical-mechanical tests will be evaluated. (AU)