Hydrolysis newspaper

Cellulose, the major component of wastepaper, can be transformed into fennentable sugars by enzymatic hydrolysis. Newspaper is mostly derived fi om softwood and exhibits low enzymatic digestibility because of its high lignin content and dense structure. Additionally, chemicals such as fillers, ink, and other additives make it difficult to hydrolyze enzymatically. Thus, effective preh-eatment is n ded to increase enzymatic hydrolysis of newspaper. 

The synthesis started with levoglucosenone 4, available by the pyrolysis of cellulose, e.g. old newspapers. Bromination-dehydrobromination gave the enantiomerically-pure Diels-Alder dienophile 5, which was combined with isoprene to give predominantly the crystalline adduct 1. Hydrolysis and acetylation led to 6, which was carried on to the geometrically-defined allylic alcohol 7 via reduction with Zn-Cu couple. Overman rearrangement of 7 proceeded with high facial control, to give 8. 

Pretreated samples in our study were washed with water until neutralized to pH 7.0, but this step required a lot of water, about 300 times the weight of substrate used, because the pretreated sample was sticky and swollen. It was theorized that there was still a small amount of surfactant left in the washed fibers, and that residual surfactant may help enzymatic hydrolysis. Figure 4 shows the effect of residual surfactant after pretreatment on digestibility at 72 h. To see this effect, newspaper was pretreated without surfactant, and then a given amount of surfactant was added to... 

A study was conducted to examine the effects of several parameters on the yields of enzymatic hydrolysis for two major MSW components namely, newspaper and corrugated cardboard [74], The primary aim was to try to determine the modifications of MSW that would lead to increased conversions to ethanol. A full complement cellulase system from T. reesei QM 9414G was used. The enzyme system consisted of endoglucanase,... 

Castanon, M., and Wilke, C. R. 1981. Effects of the Surfactant Tween 80 on Enzymatic Hydrolysis of Newspaper. Biotech. Bioeng., 23,1365-1372. 

Park, J. W.,Takahata, Y., Kajiuchi,T., and Akehata,T. 1992. Effects of Nonionic Surfactant on Enzymatic Hydrolysis of Used Newspaper. Biotech. Bioeng., 39,17-120. 

Enzyme activity loss because of non-productive adsorption on lignin surface was identified as one of the important factors to decrease enzyme effectiveness, and the effect of surfactants and non-catalytic protein on the enzymatic hydrolysis has been extensively studied to increase the enzymatic hydrolysis of cellulose into fermentable sugars [7, 9 19]. The reported study showed that the non-ionic surfactant poly(oxyethylene)2o-sorbitan-monooleate (Tween 80) enhanced the enzymatic hydrolysis rate and extent of newspaper cellulose by 33 and 14%, respectively [20]. It was also found that 30% more FPU cellulase activity remained in solution, and about three times more recoverable FPU activity could be recycled with the presence of Tween 80. Tween 80 enhanced enzymatic hydrolysis yields for steam-exploded poplar wood by 20% in the simultaneous saccharification and fermentation (SSF) process [21]. Helle et al. [22] reported that hydrolysis yield increased by as much as a factor of 7, whereas enzyme adsorption on cellulose decreased because of the addition of Tween 80. With the presence of poly(oxyethylene)2o-sorbitan-monolaurate (Tween 20) and Tween 80, the conversions of cellulose and xylan in lime-pretreated com stover were increased by 42 and 40%, respectively [23]. Wu and Ju [24] showed that the addition of Tween 20 or Tween 80 to waste newsprint could increase cellulose conversion by about 50% with the saving of cellulase loading of 80%. With the addition of non-ionic, anionic, and cationic surfactants to the hydrolysis of cellulose (Avicel, tissue paper, and reclaimed paper), Ooshima et al. [25] subsequently found that Tween 20 was the most effective for the enhancement of cellulose conversion, and anionic surfactants did not have any effect on cellulose hydrolysis. With the addition of Tween 20 in the SSF process for... 

We investigated factors that affect enzymatic hydrolysis of newspaper, such as ash content, substrate size, and ink (10). Results sho d that ink had a significant effect on en2ymatic digestibility, whereas ash content and substrate size had a very small effect. Therefore, it was concluded that ink removal from newspaper is prerequisite for en2ymatic hydrolysis. 

Figure 5. Effect of input stage ofNP-5 on enzymatic digestibility of newspaper. (1 4 w1% ammonia and NP-5 add together in pretreatment stage, 2 4 wt% ammonia adds in pretreatment stage and then NP 5 in hydrolysis stage.)...

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