Carbon from thermal decomposition

Removal of the primary reactor heads revealed warpage over approximately one-half of the upper tube sheet and showed evidence of leakage at a number of points on the bottom tube sheet. Many tubes in the area of the upper tube sheet warpage were burned through while the space between these tubes was solidly blocked with carbon from thermal decomposition of the organic coolant. Review of the reactor design indicated that cooling of the reactor should have been more than... 

Reaction of the glycol, 70, affords an oxazolidinone rather than the expected carbamate (71) on fusion with urea. It has been postulated that the urea is in fact the first product formed. This compound then undergoes 0 to N migration with loss of carbon dioxide reaction of the amino alcohol with the isocyanic acid known to result from thermal decomposition of urea affords the observed product, mephenoxolone (74) this compound shows activity quite similar to that of the carbamate. An analogous reaction on the glyceryl ether, 75, affords metaxa-lone (76). 

The production of steel begins when iron ore is fed into a blast furnace (Fig. 16.39). The furnace, which is approximately 40 m high, is continuously replenished from the top with a mixture of ore, coke, and limestone. Each kilogram of iron produced requires about 1.75 kg of ore, 0.75 kg of coke, and 0.25 kg of limestone. The limestone, which is primarily calcium carbonate, undergoes thermal decomposition to calcium oxide (lime) and carbon dioxide. The calcium oxide, which contains the Lewis base O2", helps to remove the acidic (nonmetal oxide) and amphoteric impurities from the ore ... 

Similarly, the MgO content of the ashes is largely derived from thermal decomposition of magnesian carbonates. This process also expels water from hydrated minerals present in the oil shale. The Fe-sulphide content of the original shales is oxidized to ferric oxides and sulphates in the ash (expressed as S03 in Table 4). 

Primary alcohols in particular give an M — 18 peak due to loss of water from the molecular ion although this peak may partly arise from thermal decomposition of the alcohol in the ion source. Initial migration of a hydrogen on the alkyl chain is followed by cleavage of the carbon-oxygen bond, see, for example, the spectrum of propan-l-ol, Fig. 3.81, which shows strong peaks at m/z 59, 42, 31... 

All those results are concordant with other found in literature [6, 7] where the CO is the majority product fi-om the carbonate decon osition in presence of C. Up to 650 C CO and C02 come from thermal decomposition of organic matter and from this temperature the inorganic decomposition starts mainly carbonate decomposition. As these reactions are endothermic they are tfacrmodynamically favoured a higher temperatures. So, as ten erature increases both peaks, CO and CO2, are greater, mainly the CO ones. 

The catalysts are prepared from hydroxides or carbonates by thermal decomposition. Equilibrium pressures for decomposition of carbonates and peroxides are shown in Fig. 3.4. lb obtain oxides from hydroxides or carbonates, high temperature pretreatment is required. During pretreatment, evolution of H2O, CO2, and O2 occurs. Evolution of H2O begins at about 673 K as Mg(OH)2, Ca(OH)2, and commercially available BaO are heat-treated in vacuo Carbon dioxide starts to evolve at a temperature slightly higher than that for H2O evolution. From commercially available... 

Synthesis gas is obtained either from methane reforming or from coal gasification (see Coal conversion processes). Telescoping the methanol carbonylation into an esterification scheme furnishes methyl acetate directly. Thermal decomposition of methyl acetate yields carbon and acetic anhydride,... 

Thermal decomposition of hydroxyalkyl hydroperoxyalkyl peroxides produces mixtures of starting carbonyl compounds, mono- and dicarboxyHc acids, cycHc diperoxides, carbon dioxide, and water. One specific hydroxyalkyl hydroperoxyalkyl peroxide from cyclohexanone (2, X = OH, Y = OOH) is a soHd that is produced commercially as a free-radical initiator and bleaching agent (see Table 5). On controlled decomposition, it forms 1,12-dodecanedioic acid (150). 

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