Effect of peroxyacid (a mixture of peroxymonosulfuric acid and peroxyacetic acid) pretreatment on oxygen delignification of kraft pulp from eucalyptus was studied, and the conditions of pretreatment (e.g. DTPA charge,...Effect of peroxyacid (a mixture of peroxymonosulfuric acid and peroxyacetic acid) pretreatment on oxygen delignification of kraft pulp from eucalyptus was studied, and the conditions of pretreatment (e.g. DTPA charge, peroxyacid charge, pretreatment time, pretreatment temperature and pH value) were optimized. The results show that peroxyacid pretreatment prior to oxygen delignification could enhance oxygen delignification of kraft pulp, and result in selective delignification and increased delignified-pulp brightness. The optimum conditions of peroxyacid pretreatment were as follows: peroxyacid charge 3% (on peroxymonosulfuric acid), 60℃, 30min, 12% pulp consistency, pH5.0. Pretreatment with 0.5%DTPA was essential before peroxyacid pretreatment. Under the optimum conditions, the degree of delignification and brightness of final pulp were increased by 12.4% (from 44.9% to 57.3%) and 4.9%(ISO, from 54.0% to 58.9%) respectively while maintaining a similar viscosity of final pulps compared to single oxygen delignification.展开更多
用过氧酸对大豆磷脂进行羟基化改性,主要研究了双氧水用量对羟基化磷脂碘值和过氧化值的影响;考察了羟基化改性对磷脂加脂革在存放、干/湿热、光照等条件下性能变化的影响。结果表明,当双氧水的用量为40%时,羟基化磷脂的碘值降至14.51 g...用过氧酸对大豆磷脂进行羟基化改性,主要研究了双氧水用量对羟基化磷脂碘值和过氧化值的影响;考察了羟基化改性对磷脂加脂革在存放、干/湿热、光照等条件下性能变化的影响。结果表明,当双氧水的用量为40%时,羟基化磷脂的碘值降至14.51 g I_(2)/100 g。对磷脂进行羟基化改性有效解决其加脂皮革在存放、干/湿热和光照等条件下的异味、六价铬上升、柔软度下降和黄变等问题。但由于羟基化改性大豆磷脂中过氧化物的生成,需要进一步研究消除过氧化物的方法,以达到彻底解决磷脂加脂革中六价铬及异味的产生问题。展开更多
文摘Effect of peroxyacid (a mixture of peroxymonosulfuric acid and peroxyacetic acid) pretreatment on oxygen delignification of kraft pulp from eucalyptus was studied, and the conditions of pretreatment (e.g. DTPA charge, peroxyacid charge, pretreatment time, pretreatment temperature and pH value) were optimized. The results show that peroxyacid pretreatment prior to oxygen delignification could enhance oxygen delignification of kraft pulp, and result in selective delignification and increased delignified-pulp brightness. The optimum conditions of peroxyacid pretreatment were as follows: peroxyacid charge 3% (on peroxymonosulfuric acid), 60℃, 30min, 12% pulp consistency, pH5.0. Pretreatment with 0.5%DTPA was essential before peroxyacid pretreatment. Under the optimum conditions, the degree of delignification and brightness of final pulp were increased by 12.4% (from 44.9% to 57.3%) and 4.9%(ISO, from 54.0% to 58.9%) respectively while maintaining a similar viscosity of final pulps compared to single oxygen delignification.
文摘用过氧酸对大豆磷脂进行羟基化改性,主要研究了双氧水用量对羟基化磷脂碘值和过氧化值的影响;考察了羟基化改性对磷脂加脂革在存放、干/湿热、光照等条件下性能变化的影响。结果表明,当双氧水的用量为40%时,羟基化磷脂的碘值降至14.51 g I_(2)/100 g。对磷脂进行羟基化改性有效解决其加脂皮革在存放、干/湿热和光照等条件下的异味、六价铬上升、柔软度下降和黄变等问题。但由于羟基化改性大豆磷脂中过氧化物的生成,需要进一步研究消除过氧化物的方法,以达到彻底解决磷脂加脂革中六价铬及异味的产生问题。
