Method of separating solid paraffin wax or a paraffin wax concentrate from oil containing paraffin wax

摘要

Oil is dewaxed by a flotation process, wherein the viscosity of the oil is kept down to a value of not more than 50 centipoise at the working temperature, if necessary by adding a diluent for the oil which does not dissolve the wax. In the flotation process, the oil is cooled, the solid paraffin wax particles are removed by passing a gas through the oil, and the foam of wax is removed. Gases mentioned are air, nitrogen, methane and propane. Diluents specified are propane, methyl ethyl ketone, benzene, sulphur dioxide-benzene mixtures and dichloroethane. Oil remaining in the wax concentrate obtained by the flotation process may be removed by pressing or by treating with a solvent for the oil, such as methyl isobutyl ketone, propane, or a mixture of methyl ethyl ketone and benzene. The oil to be dewaxed may be a gas oil. A paraffin wax concentrate prepared by this process may be further treated by the solvent dewaxing process described in Specification 733,067, using, for example, dichloroethane as solvent and the sodium salt of heptadecyl-9-hydrogen sulphate as the surface-active agent.ALSO:Oil is dewaxed by a flotation process, wherein the viscosity of the oil is kept down to a value of not more than 50 centipoise at the working temperature, if necessary by adding a diluent for the oil which does not dissolve the wax. In the flotation process, the oil is cooled, the solid paraffin wax particles are removed by passing a gas through the oil, and the foam of wax is removed. Gases mentioned are air, nitrogen, methane and propane. Diluents specified are propane, methyl ethyl ketone, benzene, sulphur dioxide-benzene mixtures and dichloroethane. Oil remaining in the wax concentrate obtained by the flotation process may be removed by pressing or by treating with a solvent for the oil, such as methyl isobutyl ketone, propane, or a mixture of methyl ethyl ketone and benzene. The oil to be dewaxed may be a gas oil. A paraffin wax concentrate prepared by this process may be further treated by the solvent dewaxing process described in Specification 733,067, [Group III], using, for example, dichloroethane as solvent and the sodium salt of heptadecyl-9-hydrogen sulphate as the surface-active agent.