CS217332B1 - Vyokoktocan autobenzin with balanced anti-knock properties - Google Patents

Abstract

The invention describes the production of high-octane motor gasolines for engines with large compression ratios from components with very different anti-knock properties in their distillation fractions and mixtures of alkyl leads, the resulting product having a balanced characteristic along the distillation curve and high anti-knock characteristics as a whole. The essence of the invention lies in the fact that a mixture of two products of thermal cracking of a mixture of hydrocarbons in a ratio of 2:1 to 1:5 of the lower-boiling component to the higher-boiling component and 0.1 to 6 g Pb/1 as a mixture of TEO and TMO in a ratio of 3:1 to 1:3 is added to a mixture of catalytic reformate of defined properties.

Description

The invention relates to high-coke motor gasolines for engines with high compression ratios, formed from components 3 with very different anti-knock properties in their distillation fractions and mixtures of alkyl leads, whereby the resulting product has a balanced octane characteristic along the distillation curve and a high anti-knock characteristic as a whole, and is particularly suitable for high road octane numbers even at high speeds.

-High-octane gasolines are consistently one of the most important products from petroleum. There are a number of secondary processes for processing petroleum fractions, which produce hydrocarbon mixtures boiling in the range of 30 to 200 °C and these form the components of the resulting high-octane gasolines together with various anti-knock additives, or possibly other hydrocarbon additives. * Modern gasolines for engines with a high compression ratio are subject to a number of requirements of various kinds so that their use under all conditions is optimal and that the combustion products are harmless to the surrounding world. Modern gasolines must have appropriate volatility, anti-knock properties and stability during the operation of cars.

The most important properties of motor gasolines are anti-knock properties measured both under laboratory and operating conditions. The standard is octane numbers by research or motor method and also road octane numbers at low and high engine speeds. There are relations between laboratory values and operating values and there are known ways of influencing octane numbers at high engine speeds. Motor gasolines are produced to achieve maximum efficiency by combining components and conditions of their production and also by dosing anti-knock agents and possibly other additives. The main components are products of gasoline reforming, cracking of heavy oil fractions, isomerization of n-alkanes, alkylates of C ₂ -C^ olefins with isobutane and primary oil fractions. Non-olefin gasolines usually have unbalanced anti-knock characteristics, as they are composed of high-octane aromatics with low-octane light components. More balanced characteristics are achieved by adding tetramethyl lead, which, however, at lower concentrations gives a smaller increase in octane number than tetraethyl lead. A balanced antiknock characteristic is formed by cracked gasolines, the production of which assumes an excess of middle oil fractions, which are, however, not available. Thermal cracking products are usually not suitable for motor gasolines, because they are very unstable and, moreover, their content of Cg-Οθ aromatics predetermines them for another use: after total hydrogenation of olefins, aromatics are extracted from them. However, this produces a low-quality raffinate with octane numbers of around 60. It is known that the stability of fractions from thermal cracking can be increased by low-temperature hydrogenation, when practically all compounds from which resins can form are removed. In addition, the formation of resins can be prevented by antioxidants.

A new composition of high-octane gasoline with an OCM of 88 to 100 has now been found, which is the subject of this invention. High-octane gasoline with balanced anti-knock properties, within the range of the distillation curve according to the invention, consists of 40 to 60 vol. % of the basic mixture of catalytic reformate and light hydrocarbon mixtures with a boiling point of up to 65 or up to 140 °C, further 10 to 40 vol. % of two products of thermal cracking of mixtures of hydrocarbons from C ₂ to C^g, of which the light fraction (A) has a boiling point of 20 to 70 °C and contains mainly and Cg saturated and unsaturated hydrocarbons practically free of aromatics and olefins and its Reid pressure

217 332 does not exceed 150 *±ea also AS fraction (B) with a boiling point range of 130 to 250 °C, preferably up to 190 °C, is practically free of C _fc to Cg aromatics and contains only monoolefins in addition to C^, or C-^q aromatics, with the volume ratio A : B being from 5 s 1 to 1 s 5 prr. range of octane numbers VM of finished motor gasolines from 88 to 100 units, and 0.1 to 0.6 g Pb/1 as a mixture of TEO and TMO in a ratio of 3:1 to 1:3. In the basic mixture, the volume ratio of catalytic reformate and light hydrocarbon fractions with a boiling point of up to 65 °C and up to 140 °C is 2:3 to 3:1. The catalytic reformate has an unleaded OCMV of 86 to 92 and a vapor pressure of 20 to 60 kPa. Light hydrocarbon mixtures do not contain olefins and the difference between OCMV and OCMV is 0 to 5 units. It is clear from the characteristics of the components of the basic mixture that there is a certain range of suitable ratios of both main components. It is also clear that relatively lower quality reformate can be used even for high-octane products. The light components then compensate for the disadvantages of olefinic gasolines with their ratio between octane numbers.

The production of this gasoline will result in savings of light alkane gasolines for the production of gaseous olefins and/or reformate for the production of aromatics, especially C? and Cg.

By detailed examination of a large set of mixtures of the above refinery products, the ratios of components were found, in which the non-additive bonuses of mixing olefinic and non-olefinic gasolines are maximally applied both in anti-knock properties and in the volatility of the finished products. The most important is the determination of the range of addition of olefinic components to the so-called hydroskimming gasolines and the choice of two olefinic fractions and their ratio. This can be changed according to the requirement for anti-knock character and volatility, while the effect is optimal in the found ratio range. The concentration of lead and its quality in the finished product are inextricably linked with the newly prepared motor gasolines. By choosing the ratio of both added hydrocarbon components, their concentration and the concentration and type of alkyl lead, it is possible to save a maximum of light components, or aromatics from the reformate, and using non-additivity, more light fractions from the thermal cracking of hydrocarbons can be processed. Thermal decomposition mainly refers to pyrolysis at temperatures of 550 to 900 °C.

The invention implicitly contains an important new finding that the separation of both fractions\ thermal cracking and their mixing in a given ratio leads to improved utilization and maximum savings of components, or conversely to a possible increase in production. A very significant finding is the introduction of a mixture of TEO and TMO into olefinic motor gasolines. These otherwise have low octane numbers determined directly in real multi-cylinder engines. The difference compared to non-olefinic gasoline is usually up to 4 units and it is dangerous to use such gasolines at full load due to possible rapid damage to the engines.

The advantages of the invention are shown in the examples presented.

Examples

In the refinery, for blending motor gasolines with OČVM 90 and 96 from primary gasoline, light gasoline up to 130 °C (component C), light gasoline up to 65 °C (component D) and catalytic reformate, the OČVM of which varied from 80 to 99 depending on the severity of the process (E) were obtained. Two fractions from gasoline pyrolysis and diesel fuel containing Cg-C^g hydrocarbons (boiling point 30 to 360 °C) (components A and B) were also used for blending. Main analyses of the mentioned fractions and with sensitivity to lead

217,332 are listed in Table 1. Catalytic reformate was obtained at a pressure of 2.8 to 3.2 MPa and at temperatures of 505 to 510 °C on a Pt-Re catalyst. Pyrolysis fractions were isolated as a broad gasoline product by redistillation after hydrogenation removal of unstable components at 105 to 110 °C, 4.2 MPa on a Pd catalyst (0.3% Pd on alumina).

Two motor gasolines with octane numbers 91 and 96 were mixed according to the invention and without the use of the invention. 0.4 and 0.65 g Pb/1 were added to them in the form of a mixture of TEO and TMO in a mass ratio of 1:1. The recipes are given in Table 2. The analytical values of the prepared gasolines and a comparison with the values calculated on the basis of linearity are given in Table 3. All the advantages of the invention are obvious from the table: from the found bonus in the octane number it follows that it is possible to increase production by supplying a low-quality component by 15 to 10%, to reduce the lead concentration by 0.2 to 0.3 g Pb/1 in both types of motor gasolines. By parallel division into two high-octane gasolines with different octane numbers, up to 10% more savings of reformate or light components for pyrolysis are obtained than when dosing the same mixture of pyrolysis gasolines into both gasolines or using pyrolysis gasoline without redistillation and division. The mixture of TEO and TMO selected according to the invention for gasolines with pyrolysis fractions brings a more advantageous bonus compared to the usually recommended TEO than for non-olefinic gasolines. When comparing the ratios of TEO and TMO in further experiments, the mixture of TEO:TMO 1:1 proved to be the most advantageous, while when reducing the lead concentration, the most advantageous bonuses were achieved when increasing the TEO concentration to practically the limit recommended by the invention (3:1). From the point of view of road octane numbers, tetramethylol in the mixture compensates for the negative effect of the olefins present, so that gasolines according to the invention do not have increased knocking at high engine speeds. This knocking is otherwise much more dangerous than at low speeds.

Table 1

Ingredients for mixing gasoline Folder C D E A B ^day 20 0.684 0.650 0.770 0.650 0.897 dist.range °C 40 to 128 30 to 65 40 to 180 33 to 48 166 to flavors % wt. 10.5 0 50.5 0 77.6 olefins % wt. 0.6 0 0.6 48.1 22.4 vapour pressure kPa 60 90 30 107 0 OCVM 62.0 75 91.0 93.5 98 OCM 61 ⁷⁵ 83 81 82 0CVM+0.4 g Pb/1 76.5 86 97.3 56.5 100 QČVM+0.60 g Pb/1 79.0 90.5 . 99.0 97.8 101.5

217,332

Table 2

Claims (3)

Recipes for mixing high-octane gasolines gasoline no. 1 the 2 2a characteristic according to the invention - according to the invention calculated OCM 91 91 96 96 recipe % vol. ingredients C 30 30 4 5 D 4 25 16 30 E 36 45 50 65 A 16 0 17 0 B 14 0 13 0 Pb g/1 (TEO) 0.4 0.6 0.4 0.6 Table 3 Analytical values of the prepared motor gasolines and differences against linear assumptions gasoline no. 1 the 2 2a calculated OCM 91 91 96 96 found values In OCVM 92.8 91.8 97.2 96.2 flavors % wt. 36.8 26.0 40.6 35.0 olefins % wt. 6.2 0 5.8 0 Pb g/1 0.40 0.60 0.40 0.60 type Pb PM-50 TEO PM-50 TMO SOČ at 5000 rpm. 91 89 95.5 96 PM-50 is the ratio of TEO : TMO 1 : 1 OBJECT IN Y N A L E From ϋ 1. High-octane gasoline with OCVM since 88 within 100 seconds balanced anti-knock properties range of the distillation curve, characterized in that it consists of a basic mixture of 90 to 60 vol. % of catalytic reformate and light hydrocarbon mixtures with a boiling point of up to 65 or up to 140 °C, further 10 to 40 vol. % of two products of thermal cracking of a mixture of hydrocarbons from C ₂ to C ₁₈ , of which the light fraction (A) has a boiling point of 20 to 70 °C and contains mainly Cj and Cg saturated and unsaturated hydrocarbons practically free of aromatics and its pressure according to Reid does not exceed 150 kPa and the heavy fraction (B) with a boiling point range of 130 to 250 °C preferably up to 190 °C is practically free of Cg to Cg aromatics and contains only monoolefins in addition to Cg or C _1Q aromatics, with a volume ratio of A : B from 5 : 1 to 1 : 5 and 0.1 to 0.6 g Pb/l as a mixture of TEO and TMO in a ratio of 3 : 1 to 1 : 3. 217,332 2. High-octane gasoline according to item 1, characterized in that the basic mixture contains 90 to 60% by volume of catalytic reformate and a light hydrocarbon fraction with a boiling point of up to 65 °C and up to 140 °C in a ratio of 2:3 to 3:1 by volume, wherein the catalytic reformate has an unleaded OČVM of 86 to 92 and a vapor pressure of between 20 and 60 kPa. 3'. High-octane gasoline according to item 1, characterized in that the light non-hydrocarbon mixtures in the base fraction do not contain olefins, their difference between OČVM and OČMM is 0 to 5 units.