微波辐射纸浆多段漂白工艺研究

Study on multiprocessing bleaching of paper pulp with microwave radiation

采用正交试验方法对纸浆多段漂白工艺中NaOH用量、辐射功率、碱处理时间及漂白工艺组合等因素进行了优化,并用红外光谱和纤维分析法对微波辐射纸浆漂白机理进行了研究。多段漂白的最佳工艺条件是:一段H2O2漂白,微波辐射功率240W,处理时间2.5min,H2O2用量5%,NaOH用量4%;二段NaOH碱处理,微波辐射功率200W,处理时间1min,NaOH用量3.5%;三段NaClO漂白,微波辐射功率240W,处理时间2.5min,NaClO用量4.2%,NaOH用量1%。在该工艺条件下,纸浆白度达78%ISO以上。红外光谱检测发现反应后木素的结构骨架大体上不起变化。纤维分析测定结果发现纸浆纤维形态基本上没有发生变化。

The experiment conditions such as NaOH dosage,microwave radiation power,NaOH process time and bleaching processes assembling in multiprocessing bleaching of paper pulp were optimized by using the method of orthogonal test. The mechanism of straw pulp bleached by microwave radiation was studied by infrared spectroscopy （IR） and fibre analysis. The best conditions for multiprocessing bleaching of paper pulp could be as following that firstly,H2O2 bleaching,microwave power was 240 W,process time was 2.5min,H2O2 dosage was 5%,NaOH dosage was 4%; secondly,NaOH processing,microwave power was 200 W,process time was 1min,NaOH dosage was 3.5%; thirdly,NaClO bleaching,microwave power was 240 W,process time was 2.5 min,NaClO dosage was 4.2%,NaOH dosage was 1%. In optimal process,the whiteness of paper pulp could reach more than 78%ISO. IR results proved that the configuration of the lignin was almost the same as before reaction. The fiber analysis indicated that the form of the pulp fiber did not vary compared with that before reaction.