Abstract: A process for removing iron impurities, inter alia iron or iron compounds, from petroleum oil distillation residues is disclosed in which a high gradient magnetic separator incorporates a pack of ferromagnetic fillers in the form of a generally flat or curved sheet-like strip. The ferromagnetic filler is a Fe--Cr alloy of a selected composition and the strip is of selected geometric characteristics such that the rate of removal of iron impurities can be maintained substantially at a maximum throughout the separation mode of operation prior to and after washing of the ferromagnetic filler.

Abstract: The present invention relates to a supply system for pre-treating a petroleum distillation residual oil to be fed to a hydrogenation apparatus. In order to remove iron fine particles having a particle size of less than 25.mu. in the feed oil which could be not removed in the prior art, by constituting a system comprising a heater for heating the feed oil to a given temperature by heat exchange with a high temperature bottom oil of a fractionating tower after hydrogenation treatment of the feed oil, a filter equipped with a back washing mechanism for filtering solid materials in the feed oil after heating, and a high gradient magnetic separator for magnetically separating magnetic iron fine particles having a particle size of less than 25.mu. contained in the feed oil.

Abstract: A process is disclosed for refining distillation residual fractions of a crude petroleum oil. The process employs a high gradient magnetic separator for magnetically depositing iron impurities from such distillation residual oil onto a ferromagnetic filler in the separator. The ferromagnetic filler is cleaned at predetermined intervals by a selected class of washing liquids so that the refining operation can be carried out continually.

Abstract: A method of performing an oxidation reaction in which an alkali hypohalite is used as an oxidizing agent which comprises: carrying out the oxidation reaction in an aqueous medium with concurrently distilling off a solvent used in the reaction as the reaction proceeds under a reduced pressure.The method is in particular useful for the oxidation of diacetone-L-sorbose to diacetone-2-keto-L-gulonic acid in water. The reaction temperature is so accurately controlled that the same optimum yield of diacetone-2-keto-L-gulonic acid is obtained by the use of a reduced amount of sodium hypochlorite as compared with the conventional manner of reaction under atmospheric pressure.

Abstract: A process for preparing a fluid for traction drive from a fraction containing compounds having at least four aromatic rings is disclosed. The fraction is a by-product produced at the time of the preparation of alpha-methyl-benzylalkylbenzenes by alkylation of at least one compound selected from C.sub.7 -C.sub.10 alkylbenzenes with styrene in the presence of an acid catalyst. The process comprises the steps of decomposing the fraction in an atmosphere of hydrogen at a predetermined temperature and pressure, collecting a decomposition product having a boiling range not higher than 450.degree. C. and then subjecting the decomposition product to nuclear hydrogenation at aromatic rings thereof in the presence of a catalyst capable of nuclear hydrogenation.