Total Chlorine-Free Bleaching of Populus deltoides Kraft Pulp by Oxone

Autor: Hosein Resalati, Mohsen Miri, Farhad Zeinaly, Ali Ghasemian
Rok vydání: 2015
Předmět:
Zdroj: International Journal of Carbohydrate Chemistry. 2015:1-8
ISSN: 1687-935X
1687-9341
DOI: 10.1155/2015/381242
Popis: Since the bleaching process is one of the most important environmental pollutant stages in the pulp and paper industry, here, the total chlorine-free (TCF) bleaching of poplar kraft pulp by applying Oxone and peroxide under alkaline conditions has been investigated. The pulp samples were bleached in two stages of Oxone (OX) treatment using an AOX1OX2 sequence (A: acid pretreatment), and then the treated pulps were bleached by peroxide (P) to achieve target brightness (about 80%). The influence of various reaction parameters such as alkali charge, temperature, reaction time, and bleaching agent dosage was optimized. The final achieved brightness was more than 78%. Accelerated aging experiments showed more stability in brightness for the Oxone treated pulp, because alkali Oxone bleaching stops thermal degradation. Similarly, the AOX1OX2P bleaching sequence was found to be effective in regaining some strength that had been lost during acidification of the pulp. Improvement in pulp strength made with acid treatment was achieved along with significant amount of lignin removal and it demonstrates the feasibility of Oxone in TCF bleaching. Furthermore, other results indicated the feasibility of Oxone bleaching as an environmentally favorable alternative TCF bleaching sequence, compared with elemental chlorine-free bleaching approaches and also other TCF bleaching sequences.
Databáze: OpenAIRE