Residues, cellulosics

Infrared Examination of the Residues. Cellulose Triacetate Film. ATR infrared spectra of the films irradiated at 313 mfx both in vacuum and in the presence of oxygen showed no change from those before irradiation. ATR infrared spectra of the films after irradiation at 253.7 nty, both in vacuum and in the presence of oxygen, showed additional absorptions at 5.8 and 7.85 microns, which were attributable to carboxylic acids. In some cases absorptions at 6, 10.4, 11.5, and 12.4 microns were observed, indicating the presence of unsaturation. 

Figure 2. Rate of change of degree of polymerization of H5PO -swollen cellulose by Ct and Cx enzymes of T. koningii cellulose. Residual cellulose was dissolved in Cadoxen (46) and the degree of polymerization determined viscometrically (46).

It is a common observation (23,24) that the enzymes are not fully recovered from cultures due to binding to residual cellulose in the medium. Some workers (25) have attempted to avoid this problem by prolonging the culture period until all of the cellulose has been depleted. This is not only time-consuming but permits a lengthy exposure of these enzymes to the cells, substrates, and other enzymes of the culture incurring the risk of partial degradation of the native enzymes. 

The cellulolytic enzymes of fungi are mostly present in the liquid in which the organism has been grown. The fungus is normally cultured in a liquid medium containing cellulose and different mineral salts. The culturing process is followed by filtration or centrifugation to remove the cells and residual cellulose. 

Matrices covered in this section are very diverse. Examples listed in Table 13.3 include silage juice, fermentation products, hydrolysated biomass residue, cellulose polymer, and also biological specimens. Although these matrices do not strictly classify as environmental samples, some analytical methods dealing with these matrices were included to show their unique approach. Motivations for the analyses are as diverse as the matrices themselves. 

A great deal of work has been done on the effect of aqueous alkali on cellulose, from the viewpoint of the pulping industry (e.g., 16-28.48-59). The minor organic volatile products observed here at similar temperature to those used in Kraft pulping (150-180°C) eventually lead to colored product formation, which is of concern to the paper industry. The formation of acetone from cellulose has long been known. Generally, most interest has been shown in the nature of the residual cellulose after alkali treatment, not in the nature of the volatiles. From the viewpoint of determining the chemistry of oil formation from cellulose, the intermediate volatile products are all-important and the residual cellulose is of little interest. 

Figure 4. Relation of time of hydrolysis to residual cellulose (rate of hydrolysis is proportional to...

Another example of integration is the production of levoglucosan obtained as a result of furfural production from the residual cellulosic part by fast pyrolysis. The schematic outline of lignocellulose processing is shown in Figure 6. 

Centrifuge the combined eluates for 5 min at 10,000 rpm in a microcentrifuge and transfer the supernatant to a new tube, being careful to leave all the residual cellulose particles behind. Lyophilize in a Speed-Vac. 

The final product resulting from the biodegradation process was composed mainly of the polyester fibres with a relatively low content of residual cellulose fibres. The mechanical properties of the polyester fibres isolated from the blend after enzymatic treatment are comparable to the standard PET fibres... 

Non-toxic wood residues Cellulose (after steam explosion) Ruminants... 

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