Surfactants newspaper

Enhancement of Enzymatic Digestibility of Recycled Newspaper by Addition of Surfactant in Ammonia-Hydrogen Peroxide Pretreatment... 

Index Entries Pretreatment newspaper ammonia hydrogen peroxide enzymatic digestibility surfactant. 

A mixture of three newspapers issued in Korea was used as substrate. Newspaper was cut into approx 0.5 x 0.5 cm pieces. The moisture of the paper was 6.8 wt% with the following composition 56.2 wt% glucan, 13.9 wt% xylan + mannan + galactan (XMG), 15.0 wt% klason lignin, and 7.4 wt% ash. The nonionic surfactants (TCI Tokyo Kasei Kogyo, Tokyo, Japan) used are listed in Table 1. 

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... 

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... 

Table IV. Effect of hydrogen peroxide or surfactant in 4 wt% ammonia solution on the composition of solid residue of newspaper...

Figure 4. Effect of HLB value in 4 wt% ammonia solution on enzymatic digestibility of newspaper, (surfactant loading = 0.5 wt%)...

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