Mild pyrolysis

The collected data were aimed for the commercial heat treatment of hardboards (24) and for curing processes proposed for some paper grades (4,6,25). They thus refer to quite a mild pyrolysis in air, for a shorter treatment period than some of the data presented here... 

For each coal, at the maximum in hydrogen content, or H/C atomic ratio, the aliphatic hydrogen content (determined by H NMR analysis) accounted for over 90% of the total hydrogen. The aliphatic hydrogen contents were 10.5% for the subbituminous coal,PSOC-1403, and 6.9% for the bituminous coal, PSOC-1266. The high aliphatic hydrogen content was associated with the presence of polymethylene chains. The early release of paraffinic material, as n-alkanes and as long chain substituents to aromatic structures, under conditions of mild pyrolysis has been observed in other research (13-15. ... 

The fuel side of a heater used for mild pyrolysis of a fuel oil will be analyzed. The ilowsketch of the process is shown in Figure 8.20, and the tube arrangement finally decided upon is in Figure 8.21. Only the temperatures and enthalpies of the process fluid are pertinent to this aspect of the design, but the effect of variation of heat flux along the length of the tubes on the process temperature... 

The cleavage of sulfoxides and sulfones bearing a (3-hydrogen, on treatment with an alkoxide [212] or on mild pyrolysis for a sulfoxide, allows the formation of a double bond. 

A major application of coal was the production of coke. This process is a mild pyrolysis process and, besides coke, large quantities of coke oven gas are also produced containing many of the base materials for the chemical industry, e.g., ammonia, acetylenes and aromatics. 

The pyrolytic reactions usually take place at temperatures higher than 250-300° C, commonly between 500° C and 800° C. The chemical transformations taking place under the influence of heat at a temperature between 100° C and 300° C are commonly called thermal degradations [4] and not pyrolysis. Mild pyrolysis is considered to take place between 300° C and 500° C and vigorous pyrolysis above 800° C. 

Conclusive evidence for structure XVIII was obtained from a study of the action of alkali on it. While its UV-spectrum in ethanol had the absorption due to a saturated aliphatic ketone (A ,ax 220, 292 m/i, loge 1.98, 1.33), in alkaline ethanol the absorption was typical of an unsaturated ketone (An,ax 245,318m/Lt, loge 3.45,1.91). The latter function had clearly been generated by the elimination process illustrated. The a,)3-unsaturated ketone, isolated as a gum by acidification, on ozonolysis afforded acetaldehyde and an acidic gum. Mild pyrolysis of the latter gave carbon dioxide and a crystalline acid which was identified as (-I- )-)3-(propionic acid (XX) by direct comparison with the synthetic racemic modification. 

All the cobalt and rhodium nitrido species reported so far derive from the prototypical trigonal-prismatic anions [M6N(CO)i5] (M = Co or Rh). - The octahedral cluster [Co(,N(CO)i3j "" has been obtained by mild pyrolysis of its precursor and is regenerated upon exposure to CO. 

Pyridyl azide (193) can be prepared by mild pyrolysis or photolysis of tetrazolo[l,5-a]pyridine. Pyrolysis at 480°C or photolysis in argon... 

The biosynthesis and chemistry of alkaloids have been discussed in a recent book on natural products (Hendrickson, 1965). Hendrickson has pointed out the important contributions made to structural chemistry by instrumental methods of analysis such as UV, IR, NMR, and ORD spectroscopy. One of the alkaloids discussed in which reference to the use of infrared spectroscopy was made was vindoline (CIII) (a compound isolated from periwinkles Vinca rosea in a search for anticancer agents). Dihydrovindoline hydrochloride on mild pyrolysis yielded a ketone C21H28-N2O2. The infrared spectrum of this compound showed absorption at 1709cm", which indicated a cyclohexanone. This result was used, together with other information, in determining the total structure. 

Torrefaction of woody biomass is a process for drying biomass to remove volatile compounds and to decompose a part of its hemicelluloses. It can be considered as a mild pyrolysis performed at 200-300 °C for several minutes in the absence of air. 

Adipate and phthalate type Mild pyrolysis - gas chromatography (Py-GC) [27]... 

Mild Pyrolysis. Occurs between 300 and 500°C, and carbon-carbon bond breakage occurs to some extent. 

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