A Study On High-pressure Hydrogenation Technology For Production Of Microcrystalline Wax

Petroleum microcrystalline wax is a special wax which is produced from the normal-vacuum distillation process of the vacuum-pressure residual oil. Its manufacture process includes the deasphalting of the vacuum-pressure residual oil, solvent refining, solvent-dewax, refining, shaping and packing. Microcrystalline wax has the characters of low penetration, perfect flexibility, huge ductility and strong intensity of solidifying colloid. With the development of science and technology, it can be widely used in the area of special wax stock, lubricating grease densifying component, chemical commodity material, medicine and foodstuff packing. The regulation and requirement put forward by all country' governments for the microcrystalline wax used in these aero are very strict. The unique physical and chemical properties and the wide usage of the microcrystalline wax were firstly summarized in this paper. The advantage of producing all kinks of high quality microcrystalline wax products from the Nanyang crude oil and the situations of the production and consumption of all over the world were reviewed. Based on the analysis of the possible industrial processes for production of microcrystalline wax and the quality of all kinks of products, a study focusing on the high-pressure hydrogenation technology was carried out. The influences of the main technical parameters including the reaction pressure, the reaction temperature, the ratio of hydrogen to oil on the high-pressure hydrogenation process of microcrystalline wax were investigated, and all kinds of productions had been produced in the 0.3*104 t/a high-pressure hydro-Vaseline unit. The experimental results indicated that by using the 85# crude microcrystalline wax from the normal order process unit as the stock, high quality micro-wax product in snow-white color can be produced. The detect data of the products made by FuShun research institute illuminate that the quality of the products meet the edible standard. By using 85#crude microcrystalline wax from the adverse order process unit, the product quality has reached the requirement of certified grade and first level grade. The problems of the quondam refine method with clay, say, the dark color and the poor oxidation stability of the products, have been resolved root and branch. The optimal operation parameters of high-pressure hydrogenation method were determined. The success in putting the high-pressure hydrogenation technology into practice has supplied a gap of industrial production of high quality micro-wax in China. The technology developed in this work occupies the leading position in China and the product quality come to the international level. It provides design parameters for the first domestic high-pressure hydrogenation equipment for production of microcrystalline wax with a capacity of 3*104 t/a. Meanwhile, the new technology has economic advantage over the old clay refine method. And this process doesn't drain off waste clay and reach the goal of reducing pollution.