Use of Additive in Peroxide Bleaching with Unbleached Kraft Pulp

크라프크 펄프 표백의 과산화수소 표백시 첨가제의 이용

Due to environmental proessures there is increasing use of hydrogen peroxide as a total or partial substitute for chlorine based bleaching agents within ECF or TCF sequences. However, to aceive satifactory brightness using peroxide alone, stages having a combination of high temperature, pressure, pH or residence time are required. It may also have negative impact on fiber quality . Therefore, it would be of advantage if vertain means could be found to make hydrogen peroxide more effective in bleacing , via shortening treaction time and allevaiating the need for such forcing reaction conditions. This can be achieve by converting the peroxide in-situ to stronger oxidant through the use of 손 bleach activator. In this study to investigate the influence of additives, such as tetraacetylethylenediamine (TAED) and Molybdate (MO) . addition on peroxide bleaching were carried out. Under alkaline conditions the bleching additives. TAED and Mo. can react H2O2 to form peracetic acid and peroxomolybdate respectively and these generated activators can improve deliginification,. The activators make it possible to bleach the pulp efficiently at low temperature in the range 50 to 7$0^{\circ}C$. Also, addition of TAED and Mo is an environmentally friendly way of enhancing the performance of peroxide bleaching can be incorporated into TCF and ECF sequences.