This section is from the "Henley's Twentieth Century Formulas Recipes Processes" encyclopedia, by Norman W. Henley and others.
In order to be able to wash out the petroleum or render it "saponifiable," the following process is recommended: Heat the mineral oil with 5 to 10 per cent of olein, add the proper amount of alcoholic lye and continue heating until the solvent (wateralcohol) evaporates. A practical way is to introduce an aqueous lye at 230° F. in small portions and to heat until the froth disappears. For clearness it is necessary merely to evaporate all the water. In the same manner, more olein may be added as desired if the admixture of lye is kept down so that not too much soap is formed or the petroleum becomes too thick. After cooling, a uniform gelatinous mass results. This is liquefied mechanically, during or after the cooling, by passing it through fine sieves. Soap is so finely and intimately distributed in the petroleum that the finest particles of oil are isolated by soap, as it were. When a quantity of oil is intimately stirred into the water an emulsion results so that the different parts cannot be distinguished. The same process takes place in washing, the soap contained in the oil swelling between the fibers and the oil particles upon mixture with water, isolating the oil and lifting it from the fiber.
Petroleum may be deodorized by shaking it first with 100 parts of chlorinated lime for every 4,500 parts, adding a little hydrochloric acid, then transferring the liquid to a vessel containing lime, and again shaking until all the chlorine is removed. After standing, the petroleum is decanted.
Mix with 1,000 parts of petroleum oil 150 parts of ground soap, 150 parts of rosin, and 300 parts of caustic soda lye. Heat this mixture while stirring. When solidification commences, which will be in about 40 minutes, the operation must be watched. If the mixture tends to overflow, pour into the receiver a few drops of soda, and continue to stir until the solidification is complete. When the operation is ended, flow the matter into molds for making the briquettes, and place them for 10 or 15 minutes in a stove; then they may be allowed to cool. The briquettes can be employed a few hours after they are made.
To the three elements constituting the mixture it is useful to add per 1,000 parts by weight of the briquettes to be obtained, 120 parts of sawdust and 120 parts of clay or sand, to render the briquettes more solid.
Experiments in the heating of these briquettes have demonstrated that they will furnish three times as much heat as briquettes of ordinary charcoal, without leaving any residue.