乙二酸处理抑制BCTMP返黄的研究

The effect of pretreatment with oxalic acid on inhibiting color reversion of BCTMP

使用乙二酸分别对杨木、雪杉、枫木BCTMP进行酸化处理,比较了不同pH值对三种BCTMP的干热诱导返黄、光诱导返黄的抑制效果。实验结果表明:采用乙二酸处理BCTMP,可以提高浆料白度,达5%～6%ISO;乙二酸处理BCTMP,均不同程度地提高浆料白度干热稳定性,PC值降低5左右,其中杨木、雪杉、枫木BCTMP的较佳酸化pH值分别是5.0、4.0、2.5;乙二酸处理杨木和枫木BCTMP,能改善浆料白度光稳定性,PC值减低3左右,其中杨木、杉木和枫木BCTMP的较佳酸化pH值分别是3.0、4.0和2.5。采用红外光谱分析,探讨了乙二酸处理BCTMP的机理。

Oxalic acid was used to treat three kinds of BCTMP, including poplar, fir and maple BCTMP, and a comparison of inhibiting effects of different pH on the dry heat-induced and light-induced color reversion was made. The results show that the brightness and bright- ness stabilization of BCTMP were improved on a certain extent with oxalic acid, and inhibiting effect was different with pH value. The paper also provides a brief analysis of the mechanism of acidification in inhibiting color reversion of BCTMP pulp by FT-IR spectrum.