[White oil purchasing and wholesale] There are five production methods of white oil

White oil, also known as paraffin oil, white oil, mineral oil. Colorless translucent oily liquid, no or almost no fluorescence, odorless and tasteless when cold, slightly petroleum-like smell when heated, insoluble in water, ethanol, soluble in volatile oils, miscible in most non-volatile oils, sensitive to light, It is stable to heat and acid, but will slowly oxidize when exposed to light and heat for a long time.

The production methods of white oil include sulfonation method (oleum sulfonation method, sulfur trioxide gas phase Sulfonation method), solvent extraction method, olefin polymerization method, hydrogenation method:

1. Fuming sulfuric acid sulfonation method

The raw material for producing white oil by the oleum sulfonation method can be the dewaxing of lubricating oil fractions (for example: minus two lines, minus three lines) oil or dewaxed hydrocracking tail oil. Since the production of white oil by the fuming sulfuric acid sulfonation method is an intermittent operation, the production efficiency of the device is low, the yield of white oil is low, and the output of acid residue as a by-product is large. 1 ton of white oil can produce about 1.6 tons of acid residue. Moreover, the acid residue contains oil-soluble sulfonic acid, free sulfuric acid and unsulfonated raw oil, so the acid residue is difficult to handle and will cause environmental pollution. Therefore, the white oil produced by the fuming sulfuric acid sulfonation method has begun to be gradually eliminated in our country.

2. Sulfur trioxide sulfonation method

The process of sulfur trioxide sulfonation method is basically the same as that of fuming sulfuric acid sulfonation method, and the principles are also the same. Its advantages are low investment, simple operation, improved sulfonation efficiency, and shortened sulfonation time. Using sulfur trioxide gas with a concentration of 6% to 8% as the sulfonation agent greatly improves the sulfonation efficiency and reduces the sulfonation time. The dosage of agent (approximately reduced by 50% to 70%), and the amount of acid residue generated (approximately reduced by 50%), and the acid residue has low inorganic salt content, can be made into activated carbon, detergent and emulsified release oil, etc. product.

3. Solvent extraction method

Solvent extraction The white oil production method is a production method proposed by the former Soviet Union and other countries in the 1980s. This method is characterized by no environmental pollution and simple equipment and process flow. The production of white oil by extraction method has higher requirements on raw materials. Neutral oil (preferably internal combustion engine oil base oil - lubricating oil base oil fraction) is used as raw material. It can produce high-quality compressor oil, medical white oil and cosmetic grade white oil.

4. Olefin polymerization method

Due to food The rapid development of industry (increasing loads, speeds and operating temperatures as much as possible) requires the provision of higher quality food-grade lubricants to meet increasingly demanding requirements. At present, olefin polymerization is used to produce white oil in foreign countries. The main reason is that the sources of raw materials are abundant and economical; and the products obtained are of high quality and are especially suitable for medical, cosmetic and food-grade applications. However, currently only branched-chain paraffin oils synthesized from α-olefins as raw materials can meet the above requirements. The white oil synthesized by this method has no naphthenes and linear molecules, so it has better viscosity-temperature properties and a lower pour point. This white oil has high purity and is free of polycyclic aromatic hydrocarbons and inorganic impurities.

5. Hydrogenation method

Hydrogenation The production of white oil by the method refers to the reaction between raw oil and hydrogen when passing through a reactor equipped with a catalyst under the conditions of a certain temperature and high hydrogen partial pressure. The sulfur, nitrogen, oxygen, metals, olefins and aromatic hydrocarbons in the raw oil are The process in which heteroatoms or compounds are removed or saturated by hydrogenation to produce saturated hydrocarbons and other reaction products. The process of producing white oil through hydrogenation using different raw materials (lubricating base oil and hydrocracking tail oil as raw materials) includes one-stage hydrogenation, two-stage hydrogenation and three-stage hydrogenation. The reaction pressure of the hydrogenation method is usually 15KPa. above.

The first-stage white oil hydrogenation process has strict requirements on raw materials - the raw materials are required to be of good quality (for example: hydrocracking tail oil after ketone-benzene dewaxing Dewaxed oil, lubricating oil base oil refined through furfural refining - ketone benzene dewaxing - clay refining, hydrotreated - hydrogen condensation reduction (isomeric condensation reduction) base oil or hydrocracking tail oil after hydrogen condensation reduction ), the aromatic hydrocarbon content of the raw material is generally less than 5%, and it must also have lower sulfur content and nitrogen content (to prevent the deactivation of the active metal components of the white oil hydrogenation catalyst (mainly Group VIII metal elements)). After a period of hydrogenation, cosmetic grade or industrial grade white oil can be obtained. When producing white oil using the normal third line, minus second line and minus third line fractions as raw materials, a one-stage series white oil hydrogenation process of hydrorefining and hydrogenation saturation can also be used. The main process flow is: first, the impurities such as sulfur, nitrogen, oxygen and metals in the feed oil are removed through the hydrofining catalyst, and then the aromatics in the feed oil are deeply saturated under the conditions of high pressure, hydrogenation and hydrogenation catalyst. This process produces high-quality, industrial-grade white oil.

The two-stage white oil hydrogenation process has strong adaptability to raw materials. The raw materials of this process come from a wide range of sources, such as hydrocracking tail oil, lubricating oil distillate (minus two and three lines), synthetic Oil, solvent-refined and solvent-dewaxed lubricating oil baseBoth high oil and neutral oil can be used as raw materials for the second-stage white oil hydrogenation process. The first section is the raw material refining section, which uses Ni-Mo or Ni-W type catalysts to remove sulfur- or nitrogen-containing compounds from the raw materials. At the same time, most of the aromatic hydrocarbons are hydrogenated and saturated. After stripping and drying, the products in the first section enter the third section. Second paragraph. When the raw material is various hydrogenated tail oils (hydrocracked tail oil, hydroisomerized dewaxed tail oil), there is no need to set up a section. The second section is the refining section after hydrogenation. Group VIII metal elements with hydrogenation-dehydrogenation activity, such as nickel, platinum, and palladium, are used as metal active components. The metal components are highly dispersed in the catalyst carrier through special treatment methods. On the catalyst, a reduction catalyst is formed to saturate the unsaturated aromatic hydrocarbons in the first stage, and the second stage product is stripped and dried to obtain a white oil product. In order to extend the service life of the second-stage catalyst, the sulfur and nitrogen content of the raw materials must be strictly controlled.

The three-stage white oil hydrogenation process is more adaptable to raw materials than the two-stage white oil hydrogenation process. The raw materials of the three-stage white oil hydrogenation process are Generally it is vacuum gas oil (VGO) or light deoiling (an oil obtained after residual oil is deasphalted by propane). The first stage is the pre-hydrogenation of the feed oil. Its main function is to remove sulfur and nitrogen in the feed oil and partially hydrogenate and saturate the aromatics in the feed oil. The main function of the second stage is to reduce the freezing point of the oil. The second stage is two hydrogenation reactors connected in series (the first reactor is hydrodewaxing and dewaxing). Condensation, the second reactor is a post-refining reactor), and the second stage can produce industrial grade white oil. The third stage is to deeply refine industrial grade white oil to produce cosmetic grade or food and pharmaceutical grade white oil. </span