Effects of sodium borohydride on peroxide bleaching of Pinus brutia Ten. and wheat straw pulps

Abstract

The addition of sodium borohydride (NaBH4) to peroxide bleaching has been investigated for its effects on the bleaching yield, mechanical and optical properties of Pinus brutia and wheat straw pulps. The pulps were subjected to four different bleaching conditions by adding charges of NaBH4 at 0%, 0.5%, 1.0%, and 1.5%, while keeping a constant hydrogen peroxide charge of 7%. The use of NaBH4 in the peroxide bleaching processes of the two pulps increased the bleaching yields. The results show that the addition of NaBH4 significantly improved the mechanical properties of the pulps, including tensile and burst indices. The optical properties of the pulps were also improved with the addition of NaBH4. The increase in mechanical and optical properties can be attributed to the reduction of residual hydrogen peroxide and the removal of metal ions, while the decrease in yellowness is due to the removal of metal ions that can cause oxidative degradation of the pulp. The findings of this study suggest that the addition of NaBH4 as an additive in peroxide bleaching is a promising approach to improve the mechanical and optical properties of P. brutia and wheat straw pulps, which can be further explored in future research.

Keywords

• peroxide bleaching
• sodium borohydride
• pinus brutia
• wheat straw
• peroksit ağartma
• sodyum borhidrür
• pinus brutia
• buğday sapı