Paraffin oil is any solid or liquid mixture of purified saturated, aliphatic hydrocarbons (paraffins) obtained from petroleum. A distinction is made between viscous paraffin (Paraffinumliquidum or Paraffinumsubliquidum),low-viscosity paraffin(Paraffinumperliquidum) and hard paraffin (Paraffinumsolidum), this distinction being based primarily upon viscosity. Paraffin, whatever the type, is obtained:
1) By distilling petroleum residue, bituminous shale or peat and output from low-temperature lignite carbonization
2) By means of a medium-pressure synthetic process involving the use of CO and H2
With paraffin slack wax precipitated during petroleum distillation is cooled, de-oiled and bleached to yield hard paraffin. In contrast, liquid paraffin is obtained by distillation. All types of paraffin, except the hard form, are colourless, clear, oily, non-fluorescent in daylight, entirely or virtually odourless, tasteless liquids. It is only when they are heated that they give off a faint smell. Paraffins are insoluble in water, poorly soluble in ethanol and soluble in ether and hydrocarbons.