Method for preparing high-grade wax by Fischer-Tropsch synthesis crude wax

Abstract

The invention relates to the field of production of high melting-point wax, and discloses a method for producing high-grade wax by Fischer-Tropsch synthesis crude wax. The method comprises the following steps: A) a hydrogenation saturation step: performing hydrogenation saturation on a raw material; B) primary separation: placing the saturated raw material in the step A) in a primary rectification unit, rectifying the raw material under certain pressure and temperature effects to obtain a light component, soft wax and crude hard wax; C) secondary separation: placing the crude hard wax obtained in the step B) in a secondary distillation unit, evaporating the material under certain pressure and temperature to obtain a first gas phase and a liquid phase; and D) third separation: placing the liquid phase in a third distillation unit, evaporating the material under certain pressure and temperature to obtain a second gas phase and superhard wax; wherein the primary rectification unit is a vacuum rectifying tower. The method can reduce the hardware cost of the employed distillation units in the separation process and increases the economic performance of a Fischer-Tropsch device.

Description

technical field [0001] The present invention relates to the production of high-melting point wax, in particular to a method for producing high-grade wax from Fischer-Tropsch crude wax. Background technique [0002] Most of the waxes on the market today are made of natural paraffin-based crude oil. It is obtained by atmospheric and vacuum distillation, followed by dewaxing, deoiling and refining of the corresponding fraction of heavy crude oil. As the reserves of paraffin-based crude oil in the world become less and less, the production of paraffin is limited. At the same time, for paraffin wax derived from petroleum, its carbon chain length is not enough, and the content of various isomers and aromatics in the raw material is high, so it is difficult to produce high-quality paraffin wax, especially paraffin wax products with high melting point (melting point > 90 ° C) However, these products are widely used in hot-melt adhesives, plastics, inks and other industries, res...

AI Technical Summary

Problems solved by technology

The wax has not undergone hydrogenation saturation treatment, and the olefins in the Fischer-Tropsch crude product are not saturated, which will inevitably affect the stability of the output paraffin

At the same time, the final stage is subjected to ordinary distillation under a very high vacuum at 1 Pa. The wax is easy to decompose and change color, and it is difficult to industrialize the scale-up. The quality and color quality of the produced wax are not high.

Images