Preparation method of bright oil

Abstract

The invention relates to a preparation method of a bright oil, which comprises the following steps: enabling light-weight deasphalted oil to be in contact with a solvent in which macro-molecule polycyclic aromatic hydrocarbon can be selectively dissolved, thus obtaining a wax-containing refined oil; enabling the wax-containing refined oil to be in contact with a dewaxing solvent, thus obtaining a dewaxed oil and a micro-crystalline wax paste; enabling a mixture of the dewaxed oil and hydrogen gas to be in contact with a hydrotreating catalyst, thus obtaining a first hydrogenated full distillate oil; respectively enabling a mixture of the first hydrogenated full distillate oil and hydrogen gas to be in contact with a hydroisomerizing catalyst and a hydrorefining catalyst, thus obtaining a second hydrogenated full distillate oil; and separating out the distillate of which the boiling point is higher than 500 DEG C from the second hydrogenated full distillate oil, wherein the distillate is the bright oil product. By using the traditional method, only a low-viscosity index bright oil product can be produced; or by using the conventional isomerization dewaxing method, a high-viscosity intermediate-base or mixed-base material of the bright oil can not be obtained. By using the preparation method provided by the invention, a bright oil product which has satisfactory kinematic viscosity, high viscosity index and low pour point and does not contain floccules at normal temperature can be produced, and the micro-crystalline wax can be produced as a byproduct.

Description

technical field [0001] The invention relates to a preparation method of bright stock. Background technique [0002] Bright oil is a type of lubricating oil base oil, used as a blending component of internal combustion engine oil, used to increase the viscosity of internal combustion engine oil in high temperature environment, or used as the main component of automotive gear oil and industrial gear oil. The basic indicators of bright stock include kinematic viscosity, viscosity index and pour point, among which kinematic viscosity is a characteristic indicator. The kinematic viscosity and viscosity index of bright oil are related to the type of crude oil, source of crude oil and production method, while the pour point is related to the depth of dewaxing. [0003] Bright oil is characterized by relatively high kinematic viscosity. Among the grades of base oils, bright oil is the type with the largest kinematic viscosity. The kinematic viscosity of bright stock at 100°C is be...

AI Technical Summary

Problems solved by technology

It is well known that the Zeolite EU-1 used in this process is a catalyst with shape-selective cracking properties for n-hydrocarbons or longer alkane side chains, and under the dewaxing conditions of its proposed catalyst system, it will cause band The side chain cracking and breaking of naphthenes with long side chains produces low-molecular products, and naphthenes with long side chain structures are important components to maintain the high viscosity index of base oils. After the long side chains of naphthenes are broken, they will Causes a decrease in the viscosity index of the base oil and leads to an increase in gas yield during processing

[0012] It can be seen that although the above-mentioned methods involve the related process of solving the cloud point of bright oil, they do not solve the problem of viscosity loss of the product, so that the viscosity grade of bright oil is degraded or the yield is reduced.

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