Patent GB-194286-A (GB)
Title: Improvement in process of purifying crude turpentine oils
IPC: C09F3/02
Filed: 1923-02-27
Abstract: Crude turpentine oils are purified by treatment with an aqueous solution of an alkaline earth hypochlorite in the absence of acid, followed by filtration, sedimentation or the like.  An example is given of the purification of the turpentine obtained in the sulphate treatment of coniferous woods.  The turpentine, after distillation, is agitated under aerating conditions with a solution of bleaching powder; an absorbent material such as "filtchar," fullers earth, silica gel, or boneblack is added and the agitation continued; the solid material is then removed by filtration, sedimentation or centrifugal action; the water in the filtrate is allowed to settle in a tank and the upper layer of purified turpentine then decanted off. In certain cases, the addition of absorbent material is unnecessary, for the impurities in the oil become oxidized by the previous treatment to products which are soluble in the water but insoluble in the oil. Specifications 10004/03, [Class 91, Oils &c.], 23875/06, 23467/10, 14315/11, 4775/12, and 18527/12, and 139,233, and 184,281, [both in Class 91, Oils &c.], are referred to.  The Specification as open to inspection under Sect. 91 (3) (a) describes also the purification of oils of copaiba, fir cones, ginger, juniper, pepper, pine, cedar and peppermint, as well as pinene, dipentene, limonene and isoprene by treatment with an "active" halogen compound, such as alkali or alkaline earth hypochlorite.  In a modification, the oils are agitated with air in a closed vessel under pressure or in presence of a catalytic agent.  A further modification consists in passing the crude oil through a bed of hydrated manganese dioxide and boneblack or in agitating the oil with hydrated lead peroxide or hydrated manganese peroxide.  This subject-matter does not appear in the Specification as accepted.ALSO:Crude turpentine oils are purified by treatment with an aqueous solution of an alkaline earth hypochlorite in the absence of acid, followed by filtration, sedimentaiton or the like.  An example is given of the purification of the turpentine obtained in the sulphate treatment of coniferous woods.  The turpentine, after distillation, is agitated under aerating conditions with a solution of bleaching powder; an absorbent material such as "filtchar," fuller's earth, silica gel or boneblack, is added and the agitation continued; the solid material is then removed by filtration, sedimentation or centrifugal action; the water in the filtrate is allowed to settle and the upper layer of purified turpentine then decanted off.  In certain cases, the addition of absorbent material is unnecessary, for the impurities in the oil become oxidized by the previous treatment to products which are soluble in the water but insoluble in the oil.  Specifications 10004/03, 23875/06, 23467/10, 14315/11, 4775/12, 18527/12, 139,233 and 184,281 are referred to.  The Specification as open to inspection under Sect. 91 (3) (a) describes also the purification of oils of copaiba, fir cones, ginger, juniper, pepper, pine, cedar, and peppermint by treatment with an "active" halogen compound, such as alkali or alkaline earth hypochlorite.  In a modification, the oils are agitated with air in a closed vessel under pressure or in presence of a catalytic agent.  A further modification consists in passing the crude oil through a bed of hydrated manganese dioxide and boneblack or in agitating the oil with hydrated lead peroxide or hydrated manganese peroxide.  This subject-matter does not appear in the Specification as accepted.