CS259764B1 - Low-lead lead-based motor gasoline - Google Patents

Abstract

Motor gasoline with a low content of antiknock agents based on lead with an octane number of 80 to 98 by the research method contains as the main component 30 to 65 vol. % of catalytic reformate, 50 to 15 vol. % of catalytic isomerizate and up to 20 vol. % of other components, especially light virgin gasolines and as an antiknock additive a mixture of C8 to Cl2 alkylaromatic hydrocarbons in an amount of 0.5 to 10 vol., obtained from the alkylation of benzene with ethylene, containing mainly C10 to C12 ethyl or/and butyl homologues of benzene, with the distillation range given by the ASTM distillation curve being 150 to 270 °C and the density being between 0.850 to 0.880 at 20 C, and TEO in an amount of up to 0.25 g Pb/l.

Description

The invention relates to high-octane motor gasolines containing a low content of lead-based antiknock agents and consisting mainly of reformates and isomerizates, or light petroleum gasolines, in which a mixture of C ₁₀ to C ₁₂ alkylaromatic hydrocarbons originating from the alkylation of benzene with ethylene is added as an antiknock additive.

The reduction of alkyl lead anti-knock agents in gasoline continues worldwide. Concentrations of 0.4 g Pb/l are now common, and in developed countries 0.15 g Pb/l.

Some gasolines are already produced completely without lead. It has been proven that any reduction in lead content is chemically demanding and means greater oil consumption. New anti-knock agents, both metallic and non-metallic, are being sought that would be cheap and have high mixed octane numbers. These are primarily oxygenated compounds, alcohols and ethers, which are already a permanent part of gasolines. Various types of alkylated aromatics are also of interest, as they come from thermal or catalytic processes.

The invention introduces a new non-metallic anti-knock agent into the solution of low-lead gasolines, namely a mixture of alkylaromatic hydrocarbons. The gasoline according to the invention has an octane number of 80 to 98 by the research method and contains as its main components 30 4? 65% by volume of catalytic reformate, 50 to 15% by volume of catalytic leomerizate, or their fractions, and up to 20% by volume of other additives of higher light virgin gasoline and as an antiknock additive, a mixture of 0.5 to 10% by volume of Ο^θ, to C ₁₂ alkylaromatic hydrocarbons, originating from the alkylation of benzene with ethylene catalyzed by aluminum chloride and up to 0.25 g Pb/1 as TEO* is added. Alkylaromatics are distilled off from mainly a part of monoethylbenzene and higher alkylaromatics above θ _12. Alkylaromatic hydrocarbons mainly contain C ₁₀ to C ₁₂ ethyl and/or butylhomologs of benzene, with the deatilization range given by the ASTM distillation curve being 150 to 270 °C, density between 0.850 to 0.880 at 20 °C. Thus, they are practically free from high-boiling components that increase the resin content in gasoline above 5 mg/100 g and the boiling point above 215 °C in the specified concentration range.

The analysis of the invention shows that for gasolines of certain provenance it is recommended to use a by-product of ethylbenzene synthesis, which is currently difficult to use, especially because it contains increased concentrations of chlorobenzene, which prevents catalytic processing. By diluting it into gasoline, the chlorine content does not exceed 10 ppm by weight, which is less than one tenth of the halogens added as propellants and alkyl lead. The definition of the invention further shows that there is a connection between the concentration of the antiknock agent in gasoline and its composition given by the distillation level, especially in terms of separation of heavy components. It is also necessary to take into account the main components and their fractions, the ratio of which can be used to adjust the concentration of the antiknock agent. The definition shows that the by-components of gasolines can be other components in concentrations of up to 20% by volume in total, e.g., pyrolysis traction, alcohols and/or ethers, ZVI, MTBE or TAME, and possibly also heterocyclic gasoline fractions. The combination of the two main components achieves such an interplay of anti-knock properties, increased octane numbers by the research method and the motor method, that the secondary components only slightly adjust this balance. The data on lead concentrations show that these are also unleaded gasolines.

The presented example shows the practical composition of an anti-knock agent designated PABY and its effect on a typical high-octane gasoline containing reformate and isomerize as the main components.

Example

The antiknock agent PABY was distilled from the residue after the production of ethylbenzene from benzene and ethylene, the properties of which are given in Table 1. The yield of the residue was 50% by weight. PABY was a water-clear, light liquid.

PABY was added in the maximum concentration according to the invention of 10% by volume to the base gasoline; extreme changes in properties and exact mixed octane numbers were determined. From Tables 2 and 3 it can be seen that the new antiknock agent PABY has mixed octane numbers 20 to 30 units higher than the octane numbers of the base gasoline in the lead concentration range of 0 to 0.25 g Pb/l (lead added as tetraethyl lead), and it is also evident that the deethylation curve shifts between 90 and 99% by volume by 5 to 15 °C higher, but the standard values for gasolines are not exceeded. The same applies to resins. An advantageous property of the new antiknock agent is less aromaticity, since the hydrocarbons have 30 to 50% of carbons bound in the side chains. The mixed octane numbers are at the level of toluene and xylenes.

In further tests with base gasoline approximately 5 units lower in OČVM used as the basis for the production of SPECIAL gasoline, the PABA ridiculous numbers increased by another 3 to 5 compared to the values given in Table 3.

Table 1

Composition of the new anti-knock agent - PABY

_d2 ° 0.880 chrome, analysis % touch dest, ASTM curve start °C 186 diethyl benzoate 56.1 10% vol. 191 butylbenzene 14.3 50% vol. 201 triethylbenzenes 20.6 90% vol; 223 95% vol. 231 to distillation 251/99 chlorine content ppm 100

table 2

Effect of PABY addition on base gasoline base gasoline (ZB)* ZB + 10% vol· PABY

d ₂ 0 ddst«curve °C start· 0.711 42 0.733 39 10% vol. to 48 47 50% of the volume 68 78 90% of the volume 154 178 95% of the volume 167 191 end 189 214 OCVM 87.8 91.6 OCM 80.5 83.0 OCVM + 0.25g Pb/1 (TEO) 95.2 97.5 OÇMM + 0.25g Pb/1 (TEO) 88.0 89.1 resin mg/100 ml 1 2 * ZB consisted of 55% obj· reformed 20% obj· isomerized · 25% obj· light prim· gasoline

Table 3

Mixed octane numbers of PABY anti-detonator

PUB** srv· toluene* xylenes OCVM 125.8 124 135 OCM 105.5 112 114 OČVM with 0.25g Pb/1 119.2 0 OÇMM with 0.25g Pb/1 99.0 - 1

* determined in gasoline with OČVM 60 ** for gasoline with OČVM 50 the mixed OČVM is 149 and the mixed OČMM is 109

Claims (2)

OBJECT OF THE INVENTION 1. Low-lead benzo-benzine gasoline 8. A method according to claim 8, characterized in that it contains as main constituents 30 to 65% by volume of catalytic reformate, 50 to 15% by volume of catalytic isomerisate or a fraction thereof and up to 20% by volume of other components, in particular light. naphtha and additive mixture as antidetonačnl Οθ through C ₁₂ hydrocarbons alkyiaromatických in amounts of 0.5 to 10 vol% ,, coming from the alkylation of benzene with ethylene catalyzed by aluminum chloride and stripped distillation predominant CEET monoetylbenzenu and higher alkylaromatics of _C12 "and TEO in amounts up to 0.25 g Pb / l, 2 gasolines according to claim 1, characterized in that a mixture of alkylaromatic hydrocarbons comprising mostly C _1Q through C ₁₂ ethyl and / or butylhomologu benzene to a distillation range of the ASTM distillation curve is 150 to 270 ° C and a density of between 0.850 to 0.880 at 20 ° C,