Preparation method for high-yield needle petroleum coke

Abstract

The invention provides a preparation method of high-yield needle petroleum coke. The preparation method comprises the following steps: uniformly mixing FCC oil slurry with haloalkane (iodomethane or ethyl iodide), polyol (polyethylene glycol, polypropylene glycol and trimethylolpropane) and boron trifluoride according to catalyst-oil ratios of 0.01 to 0.07 g / g, 0.03 to 0.08 g / g and 0.001 to 0.02 g / g, respectively; carrying out coupled catalytic polycondensation-shallow alkylation for 4-6 h at a certain temperature to produce a carbene mixture with high molecular weight and high aromaticity, which enables the cross-linking and coupling degrees of fused-ring aromatic compounds to be increased; then subjecting the obtained carbene mixture to a carbonization reaction at 550-600 DEG C for 10 to14 h so as to obtain green needle coke; and finally carrying out calcination at a high temperature of 1500 DEG C so as to obtain the needle petroleum coke. The method of the invention is a combined process of coupled alkylation-carbonization reactions, has the characteristics of controllable molecular weight and aromaticity of an intermediate and easy control of carbonization reaction depth and mesophase formation; and the obtained needle coke has the advantages of high yield and low thermal expansion coefficient, and has general yield of no less than 70% and a thermal expansion coefficient as low as 0.9*10<-6> to 1.6*10<-6> / DEG C.

Description

technical field [0001] The invention relates to a method for preparing high-yield needle-shaped petroleum coke, which belongs to the technical field of carbon materials. Background technique [0002] Needle petroleum coke is a high-quality carbon species that appeared in the 1970s. Because of its low thermal expansion coefficient, high density, low sulfur, low ash, low metal content and high conductivity, it is ideal for the production of ultra-high power electrodes, special carbon materials, Raw materials for high-end carbon products such as carbon fiber and its composite materials. According to statistics, my country needs about 200,000 tons of needle coke every year. However, in the actual production of domestic petroleum-based needle coke, the quality of needle coke is not stable enough, and there are problems such as low coke strength and excessive powder coke. These problems are serious Restricting the quality of needle coke and the processing capacity of the device, i...

AI Technical Summary

Problems solved by technology

[0004] Chinese patent CN1185491 provides a method for preparing mesophase using a cross-linking agent. The method is simple to operate, high in yield of high-quality mesophase pitch, easy to design and control the formation process and composition of mesophase, and the prepared mesophase pitch softens Low point, developed optical anisotropy and high content, excellent rheological properties, high H / C ratio, but this patent is only for model compounds, the cost is high, it is not applicable to petroleum systems, and there is no wide industrial application yet

Although the needle coke prepared by this method has excellent performance, it involves a variety of production processes, and the hydrogenation reaction is dangerous, which is not conducive to industrial practical application