A Pilot Plant Trial Using in Situ Peroxyborate for the Brightness Retention of Tmp

The possibility of using peroxyborates, produced in situ by combining aqueous alkaline hydrogen peroxide and borax, for bleaching and brightness reversion inhibition of thermomechanical pulp was investigated. The peroxyborate material was applied to BTMP paper produced in the laboratory, and from a pilot scale paper making trial. Excellent brightness retention characteristics were exhibited in both the laboratory and pilot scale paper making in situ peroxyborate application trials. A number of mechanical and structural properties of the perxoyborate paper showed significant improvement compared to control samples, or samples with hydrogen peroxide or borax applied alone.