| Auto-catalyzed ethanol-water pulping is one kind of organosolv pulping; it can completely solve the pollution problem of conventional chemical pulping. In this paper, the technology and mechanism of auto-catalyzed ethanol-water pulping of three typical non-wood fiber which are wheat straw, silvergrass, Chinese alpine rush were investigated separately. Including: the optimizing the technologic parameter of pulping; the response couse of delignification; the kinetics and the response mechanism of delignification and also preliminarily evaluating beating, bleaching and papermaking properties of three kind of pulp. TCF bleaching technology and mechanism of Chinese alpine rush EW pulp was probed into as an example. The results obtained from EW process can provide the technical support and the academic foundation for promoting the technologic progress of EW pulping.1. The results of wheat straw EW pulping showed that a cooking temperature of 195 C, liquid ratio of 1:8, an ethanol concenreation of 50% ~ 60%, and a time at Tmax of 70 minutes appeared to be desirable. Under the conditions, the screened pulp yield, kappa No. was 57.30% and 68.43 respectively. Study of dellignification course suggested that it could be divided into two phases: The first phase from the cooking to the time at Tmax of 20 min. was the bulk phase of the dilignification. During the first phase the pulp delignified by 75.39%. The second one, the period from 20 min. to 70 min. at Tmax is the residual delilgnification phase, the pulp delignified by only 11.27%. The wheat straw changed into pulp at the initial stage of bulk delignification phase with ethanol-water. The screened pulp yield was 57.30% in the fiber liberation point and kappa No. was 68.43% correspond. The linear relationship between the lignin contents of pulp and kappa No. of the screened pulp was obtained in this experiment.2. To silvergrass, the factors which influence the pulping were cooking temperature (Tmax), liquid ratio (r), cooking time at Tmax (t) and EW concenreation (C). The optimum cooking conditions were : Tmax :195 C, t: 120min., r: 1:10 and C :55%(V/V). Under these conditions, the screened pulp yield, kappa No. and total lignin (% on o.d pulp ) was 61.32%, 50, 8 and 5.43,separately.The lingnification kinetics of silvergrass occurred in two phase: principal (from beginning to 30 min.) and residual (from 30 min to end), and the delignification followed a first order reaction. The calculated Arrhenius activation energy Ep (principal phases) and Er (residual phases) was 77.13 KJ/mol and 156.7KJ/mol, respectively.IR and 1HNMR analysis showed that the structure of MWL and CL (lignin separated from black liquor) was alike. But there were more syringy (S) and parahydroxy-pheny (H) in CL, cleavage of a -ether linkages( a -O-4) was more than that in MWL.The characteristic of auto-catalyzed EW brown pulp was their easy bleach ability and beating compared with brown Kraft pulp, EW pulp with good brightness and strength properties could be produced with TCP bleaching.3. To Chinese alpine rush, the factor influencing screened pulp yield and kappa No. from great to small was both Tmax > r > C > t. In the range of pulping conditions investigated, a cooking temperature of 1801, a liquid ratio of 1:10, an ethanol concentration of 55% and a time at Tmax of 120 minutes provided a good compromise. Under these conditions, an adequate rate of delignification (kappa No. 38.13) and a high-screened pulp yield 53.18% was achieved. Total lignin in the pulp was 4.64%. Pulp properties indicated that EW pulp was beaten easily. Study of pulping mechanism suggested that delignification course could be divided into two phases: principal (from beginning to 40 min.) and residual (from 40 min to end), The percent of delignification of the two phases was 79.16% and 88.90% respectively. The unscreened pulp yield, kappa No. and total lignin in the pulp was 56.6%, 50.0, 7.10% separately at the liberation point. The linear relationship be...
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