Immobilized Metal Salen Catalysis Research Bleached Eucalyptus Pulp

Co(salen), Cu(salen), Co([H4]salen), Cu([H4]salen) complexes were encapsulated in NaY zeolite and successfully synthetized Co(salen)/Y-SB、Co([H4]salen)/Y-SB、 Cu(salen)/Y-SB、Cu([H4]salen)/Y-SB、Co(salen)/Y-IM、Co([H4]salen)/Y-IM, Cu(salen)/Y-IM and Cu([H4]salen)/Y-IM by free ligand method and impregnation method. The catalysts were characterized by FT-IR, XRD, UV-Vis, N2adsorption, TG-DTA, the results indicate that the encapsulation of metal complexes was success. These catalysts were used in eucalyptus wood pulp TCF bleaching. We can draw conclusions as follows:1、Brightness can be increased from1.68to6.79percentage points, indicating that biomimetic pretreatment improved pulp bleaching, but pulp viscosity was decreased in varying degrees, indicating that the pretreatment degraded carbohydrates.2、Biomimetic pretreatment improved pulp bleaching, but pulp viscosity was decreased in varying degrees, indicating that the pretreatment degraded carbohydrates. The final bleached pulp brightness and viscosity depended on type of oxidizing agent. Viscosity:Cat(Na2S2O8)<Cat(H2O2)<Cat(CH3COOOH);Delignification:Cat(CH3COOO H)>Cat(H2O2)>Cat(Na2S2O8).3、The bleaching pulp viscosity with methanol was higher than without methanol in imitation of enzyme pretreatment process, the highest viscosity Can improve227ml/g. Brightness was also changed,it was indicated methanol has an impact on the activity of catalyst, different catalyst had different activity.Brightness was88.90/%ISO and viscosity was736ml/g with pretreatment [Cu(salen)/Y-IM+CH3OH+CH3COOOH]. Catalysts encapsulated in supercages have good catalytic activity.4%Increased the dosage of catalyst and Na2S2O8,influence on pulp whiteness is not big, but for the degradation of carbon hydration is larger.5、Changed the bleaching process for TCF2:Cat Ep Pa P, brightness was separately88.90/%ISO and89.02%ISO and viscosity was separately761ml/g and705ml/g with pretreatment Cu(salen)/Y-IM and Cu([H4]salen)/Y-IM.Catalysts encapsulated in supercages have good catalytic activity. But from saving medicine and industrial production, The effect on TCF2process whiteness of pulp and viscosity were not significant. 6、Pulp hardness of catalyst/acid peroxide pretreatment period with methanol were higher than no methanol. It may be due to methanol chelated onto metal to hindere the formation of complex catalyst activity, thus reduced the activity of catalyst.7、In imitation of enzymatic pretreatment, emergence rate of Ep lignin was37.81%～48.54%, It was advantageous to the lignin removal in oxygen/peracetic acid.8、Compared with the blank sample the paper of tensile index, tear index and burst index, folding endurance degree changed no better with different catalyst pretreatment.9、The catalytic pretreatment can improve the physical strength of the sheet. GC-MS analysis of lignin degradation products showed that there are aldehydes, ketones, acids, alcohols, quinone. The addition of methanol increased the yield degradation products of lignin. In addition, the encapsulation of catalyst affected the decomposition of lignin, may be due to the accessibility of the catalyst.