Carbonization of wool

The carbonization of wool removes cellulose fibers and impurities by acid hydrolysis. It consists of three operations foularding in 4%-7% sulfuric acid, drying at 100-120° C ( burning ), and scouring ( scrubbing ), i.e., mechanical removal of the cellulose components. During carbonization, several chemical reactions take place namely, an N-O-peptidyl rearrangement... 

For the hydrolysis, the benzylidene compound is dissolved in 300 cc of a warm 2 per cent soda ash solution, and the solution is filtered to remove a residue of iron carbonate. The solution is then treated with 5 cc. concentrated sodium hydroxide solution (40° B6) and heated with stirring for 1 hour on a water bath. The solution becomes cloudy and the aldehyde separates in oily drops which solidify on cooling. It is dissolved in 1 1 hydrochloric acid and reprecipitated with 2 N soda solution. The yield is 13.2 grams of dry aldehyde melting at 81° (72 per cent calculated on die base used, or 94 per cent calculated on the unrecovered base). The aldehyde can be recrystallized from ligroin. It is used, for example, in the preparation of wool blue 5B (see page 305). 

Fig. 16. Steam reforming of methane on nickel (llwt%) supported on a-AFOs (BET surface area = 5.5 m /g) investigated in the TEOM. S/C is the steam to carbon molar ratio, and the catalyst bed was held in place with quartz, Fiberfrax (90% AI2O3, 10% Si02) or carbon fiber wool.

The half-life of 14C is 5,730 years. The 14C activity of living material is approximately 920 decays/hr per gram of carbon. A fragment of wool fabric from an archaeological site has an activity of 680 decays/hr per gram of carbon. The approximate date of the sample is... 

A combination of 2 parts of caustic soda and 1 part of sodium carbonate is often used in single stage boiling. Soda-ash softens the water while interacting with Ca and Mg salts (if such are present) it creates an active reaction of the medium which is most favourable for the formation of stable emulsions and suspensions increases fibre swelling, thus contributing to the release of impurities from the fibre neutralises fatty acids contained in the fabric by soap formation obviates soap hydrolysis in the presence of wool reduces the adherence of detergents to wool in the alkaline medium conditions. 

The scouring of wool differs from cotton in two essential respects. In the first place, raw wool contains anything from 30 to 60 per cent of wool grease, compared with 0-5 per cent of oil and wax in cotton. In the second place, wool is very rapidly degraded by alkali so that if the natural oils and fats are to be saponified the alkali must be applied with caution and at temperatures well below the boil. In practice, sodium hydroxide is never used because the slightest excess would raise the pH above the danger level, and milder alkalis such as sodium carbonate and ammonia or ammonium carbonate are preferred. 

Recently, a unique anteiso methyl-branched saturated fatty acid of 21 carbons, 18-methyl eicosanoic acid or 18-MEA, was identified in the outermost portion of the epicuticle, which is part of the CMC [104,106-110], 18-MEA is the predominant fatty acid in the epicuticle. It makes up approximately 40% of the surface lipid layer of wool and human hair [106,107,109], In addition to 18-MEA, other fatty acids have been isolated in smaller amounts from the epicuticle including... 

Fig. 23.13. The expanded C CP/MAS TOSS NMR spectra for the carbonyl carbon region of wool, SCMKA, SCMKA-hf, SCMKB, and HOT.

Kallonen et al. (1985) identified carbon disulfide at low levels (less than 1 pg/L) in fire gas emissions from the combustion of wool. Exposures at this level do not usually result in significant body concentration of carbon disulfide. 

Cyanide (CN) poisoning may be encountered after the inhalation of hydrogen cyanide (HCN), or after the ingestion of hydrocyanic acid or of potassium or sodium cyanides. Cyanide solutions used in electroplating may release HCN if acidified, while a number of naturally occurring nitriles are metabolized to cyanide ion in vivo. Thioyanate insecticides also give rise to cyanide in-vivo. In addition, cyanide is often present in the blood of fire victims due to the inhalation of HCN from the partial combustion of wool, silk, and synthetic polymers such as polyurethanes and polyacrylonitriles carbon monoxide is usually also present. 

M. R. Fenske and P. K. Frolich, the formation of alcohol from carbon monoxide and hydrogen J. R. Hoffman and B. F. Dodge, the formation and decomposition of methanol and A. E. Tschitschibabin, the reaction between ammonia and acetylene. The use of chromic oxide as a mordant in the dyeing of wool, COtton, and silk was discussed by L. Liechti and J. J. Hummel, and W. D. Bancroft. The last-named said that from dichromate soln. wool first adsorbs chromic acid and this is reduced to chromic oxide, which is the true mordant within limits, increasing... 

For the end-of-Ufe phase of the product, two scenarios were analysed within the scope of this study. The best case assumed direct release of the carbon sequestered in the product. Regardless of whether the product had one or more users, if the use phase was 10 years or less, all GHG emissions were treated as if they occurred at the beginning of the assessment period (i.e. in the first year). This approach was consistent with that recommended in ISO 14067 (ISO, 2013). A worst case scenario assumed that the products were landfilled. In this case, anaerobic decomposition of wool occurred, producing methane as well as CO2. Methane has 25 times the GWP of CO2 (IPCC, 2007) and landfill disposal produced a higher climate change impact as modelled based on a textile landfill dataset (PE, 2013). 

Li Qiu yu, et al. 2011. Carbon black conductive fiber in the application of blended wool fabric [J]. Journal of wool spinning technology, 11(10) 103-106. 

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