Effects of Alkali Pre-impregnation on the Chemical Components of Bamboo Chemi-mechanical Pulp
The mixed bamboo was treated with pre-press,pre-impregnation,thread rolling,lye and KRK pulping to prepare bamboo chemical mechanical pulp(CMP).The effects of alkali pre-impregnation on the chemical composition of bamboo CMP and the subsequent paper formation were discussed.The results showed that the improvement rate of nitric acid-ethanol cellulose(relative to the original bamboo slices)increased from 7.20％to 17.89％when the alkali dosage for pre-impregnation increased from 2％(measured by NaOH,the same below)to 4％.Replacing part of the pre-impregnation liquid with pre-impregnation waste liquid,the bamboo chips with 4％alkali for pre-impregnation was subjected to thread rolling,alkali treatment,KRK disk grinding and washing.When the substitution amount was 10％,the acid-insoluble lignin,ash,benzene-alcohol extract and polypentose contents in the pulp were 12.25％,0.67％,1.10％and 8.47％,respectively.Compared with unreplaced pulp(the substitution amount was 0),the reduction rates of acid-insoluble lignin,ash,benzene-alcohol extract and polypentose increased by 3.9％,13.05％,5.84％and 5.95％,respectively.When the substitution amount was 10％,the mass fractions of holocellulose and nitro-ethanol cellulose were 77.83％and 64.71％,respectively,and the pulp yield was 67.30％(for raw bamboo chips).At the beating degree of(30±0.5)SR and substitution amount of 10％,the folding strength,bursting index,tear index,break length and ring pressure index of the finished paper were 11 times,2.13(kPa m2)/g,7.34(mN·m2)/g,3.20 km and 8.4(N·m)/g,respectively.
万方数据
维普
