Grinding carbon products

Other Carbon Products Pitch may be pulverized as a fuel or for other commercial purposes in the former case the unit system of burning is generahy employed, and the same eqiiipment is used as described tor coal. Grinding characteristics vaiy with the melting point, which may be anywhere from 50 to 175°C. 

The free base is prepared by grinding the product with 25 gm of sodium bicarbonate with a small amount of water until a brown paste forms. This mixture is repeatedly extracted with ether. The ether extract is evaporated under reduced pressure. The crude base, which remains behind, is recrystallized from carbon tetrachloride, m.p. 144°-145°C dec. This product is presumed not to be quite pure because of the possibility of a-naphthaquinonimide oxime formation. 

Polycrystalllne samples of LaSrAlCu05 were prepared by solid state reaction of Aldrich cupric oxide (99.999%), strontium carbonate (99.999%), lanthanum oxide (99.999%) and aluminum nitrate (99.999%). Powders were ground with a mortar and pestle and calcined In air at 950 C for 5 days with dally grindings. The product was dark black. Thermogravlmetrlc studies with a Du Pont Thermal Analysis System by reduction In hydrogen were used to determine the oxygen composition. 

Alternatively, grind 10 g. of p-toluenesulphonyl chloride to a fine powder and add it to 30 ml. of concentrated ammonia solution (sp. gr. 0-88). Heat the mixture to boiling (FUME CUPBOARD) and cool. Filter and recrystallise the p-toluenesulphonamide from boiling water (add 1 g. of decolourising carbon, if necessary). The yield of pme product, m.p. 138°, is almost theoretical. 

Natural ground calcium carbonate has been used for years as the primary constituent of putty. Since 1945, the processing of natural calcium carbonate has seen the introduction of beneficiation by flotation (qv) to remove impurities and the development of grinding processes to manufacture finer products. Precipitated calcium carbonate was first introduced in England in 1850 commercial production started in the United States in about 1913. 

Benzyl phthalimide. Grind together 53 g. of finely-powdered, anhydrous potassium carbonate and 147 g. of phthalimide (Section IV,169) in a glass mortar, transfer the mixture to a 750 ml. round-bottomed flask, and treat it with 252 g. (230 ml.) of redistilled benzyl chloride. Heat in an oil bath at 190° under a reflux condenser for 3 hours. Whilst the mixture is still hot, remove the excess of benzyl chloride by steam distillation. The benzyl phthalimide commences to crystallise near the end of the steam distillation. At this point, cool the mixture rapidly with vigorous stirring so that the solid is obtained in a fine state of division. Filter the solid with suction on a Buchner funnel, wash well with water and drain as completely as possible then wash once with 200 ml. of 60 per cent, ethanol and drain again. The yield of crude product, m.p. 100-110°, is 180 g. Recrystallise from glacial acetic acid to obtain pure benzyl phthalimide, m.p. 116° the recovery is about 80 per cent. 

Finely-divided calcium carbonate obtained from natural sources (chalk, limestone or marble) or as a by-product of another chemical process -precipitated whiting. Strictly speaking, the term whiting should be applied only to material prepared by grinding natural chalk . 

Fig. 7 Manual grinding of the ferrocenyl dicarboxylic acid complex [Fe(ip -C5H4COOH)2] with l,4-diazabicyclo[2.2.2]octane, 1,4-phenylenediamine,piperazine, fraMS-l,4-cyclohexa-nediamine and guanidinium carbonate generates quantitatively the corresponding organic-organometallic adducts. The reaction with phenylenediamine highlights that single crystals of the adduct can be grown from solution and used to fully characterize the reaction product...

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