Newsprint reaction

Figure 8 is a schematic flow diagram for the hydrolysis of waste newsprint. Most of the process design criteria and the economic evaluations of the saccharification process have been based on newsprint as substrate. Notable analyses are those of Wilke and co-workers (21) and Humphrey (22). In the hydrolysis, the substrate is first pretreated (milling), to make it more accessible to the enzyme. Saccharification takes place in a reaction vessel, where the substrate is contacted with the enzyme solution from the fermentation vessel. Glucose solution is separated from unreacted substrate at the outlet of the vessel and the solution passes on to a concentration stage before the sugar is used in the yeast fermentation to produce alcohol. 

The light-induced increase in reflectance of newsprint at 350 nm can be attributed to photooxidative cleavage of the coniferaldehyde carbon-carbon double bond in the lignin of newsprint to produce a vanillin type group, as shown in Scheme 2. This reaction shifts the absorption maximum from 350 to 280 nm. Irradiation of bisulphite liner with uv light does not increase the reflectance at 350 nm, because the coniferaldehyde moiety has been previously consumed by treatment with bisulphite. 

Amanitins can be differentiated analytically from phalloidins by a sensitive test reaction with cinnamaldehyde that yields a deep violet color in an atmosphere of hydrogen chloride. Also, the simple color test in which a trace of a toadstool impressed on a lignin-containing paper (e.g., newsprint) moistened with concentrated hydrochloric acid develops within 5-10 min a greenish-blue color when amanitines are present 86,104) may be of some analytical value. This reaction is also characteristic of other... 

Hand eczema can occur, due to colophony, from handling paper and newsprint (without ink) (Liden and Karlberg 1992). Papers based on mechanical pulps ( environmentally friendly paper ) may have a greater potential to elicit positive patch-test reactions than papers made from other pulps. The increased use of mechanical pulps in different applications may increase the incidence of rosin-related hand eczema (Karlberg et al. 1995). 

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