New perspective bleaching with chlorine dioxide high temperature

• Grant number: 16/15572-8
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: December 01, 2016
• End date: November 30, 2017
• Field of knowledge: Agronomical Sciences - Forestry Resources and Forestry Engineering - Technology and Use of Forest Products
• Principal Investigator: Gustavo Ventorim
• Grantee: Cláudia Rodrigues de Oliveira
• Host Institution: Universidade Estadual Paulista (UNESP). Campus Experimental de Itapeva. Itapeva , SP, Brazil

Abstract

The search more environmentally viable and sustainable process, causes the pulp and paper industry to invest reducing number stages used in bleaching, order to reduce volume of effluents generated in process. Chlorine dioxide is commonly used in bleaching plants to be treated for a selective chemical reagent and quite effective in delignification cellulose pulp, besides generating a smaller amount organochlorine compounds. The effects its use normal conditions (30 min / 60 ° C) and pH between 1,9 and 3 on D0 are widely known, since effect pulp quality, use hot (120 min / 95 ° C) and at higher pHs, they were not widely studied. Accordingly, the dioxide causes hydrolysis HexA's reducing formation organochlorines. As a result, this study aims to evaluate effect using a higher pH 5.5, the ECF bleaching stage with hot chlorine dioxide (120 min / 95 ° C) compared to pH 3 in addition to check feasibility its use in sequence composed three stages, contrast to longer sequences. Being that will be use three ECF bleaching sequences OD0 (E + P) D1, ODHT, (E + P) D1, ODHTP, stage DHT present in last two sequences will be held in two different pHs 3 and 5.5. The results will be analyzed based on quality parameters of produced pulp, seeking the best results of HexA's, brightness, viscosity, kappa and brightness reversion. (AU)