Charcoal procurement

Bisulphide op Carbon.—This remarkable substance is obtained whenever sulphur comes in. oontact with red-hot charcoal. Procured in this way, it contains an excess of sulphur dissolved in it, aod must bo purified by redistilkticn at a voiy moderate heat whan about nine-tenths have distilled over, by allowing the residue to evaporata spontaneously in a capsule, very fine right rhombic crystals of Bulphnr deposit. 

These inks contain high concentrations of low-boiling solvents, and the usual practice is to dilute them further in the press room. The large volume of solvents emitted makes incineration impractical, but these solvents may be absorbed on activated charcoal, and removed l steam distillation when the charcoal is saturated. The recovered solvents may be re-used or sold however, it may be impractical to fractionate some recovered solvent blend that boil in the same temperature range, which lessens their value considerably. Therefore, although this approach is also technically and economically feasible, the difficulty in procuring the solvents used for dilution may restrict the continued use of these solvent-based inks and, hence, the adoption of solvent recovery approach. 

The commercial catalyst used for hydrogenation was a palladium on charcoal catalyst (type 37), manufactured by Johnson Matthey (UK)) with metal content 4.89% and supplied as powder. The Pd metal was d osited on the exterior sur ce of the charcoal The Pd/Ii02 catalyst was prepared using sodium tetrachloropalladate (II), supplied by Johnson Matthey (UK) and titanium dioxide, firom Degussa (Germany). The hydrogen gas was supplied by BOC (UK), with >99.98% purity and was used directly fi om cylinder. The reactant, butyne-l,4-diol 99%, was procured firom Aldrich (UK) and water and 2-propanol obtained firom Fisons (UK), were used as solvents. Additives such as lead acetate, quinoline, thiophene and triethyl phosphite were supplied by Aldrich (UK) and cupric acetate, zinc su hate, ferric nitrate and potasaum hydroxide were provided by Fisons (UK). 

This experiment seems to be decisive against the hypothesis of Mr. Lavoisier, and others, who say that the inflammable air procured by means of iron and charcoal comes from the water, and who think that by this means they can exclude phlogiston. For, according to them, neither the scales of iron, nor the charcoal, contain phlogiston, or any thing from which inflammable air can be made. ... 

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