CS253442B1 - The way to treat depressants into oil fractions - Google Patents

Abstract

Solution for using low molecular weight polyethylene, resulting from the production of polyethylene by high pressure, as an additive to medium oil fractions, especially diesel fuels and light heating oils, reducing their solidification temperatures. For reasons of improving the filterability of diesel fuels, according to the invention, fractions with reduced solubility are removed from solutions of low molecular weight polyethylene in hydrocarbons by centrifugation and/or filtration and/or settling.

Description

253442

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a process for the treatment of depressants in petroleum fractions based on low-polyalkyl polyethylene, which is a by-product of the high pressure process for the production of polyethylene.

The invention protected by MS. U.S. Pat. No. 216,286 discloses the possibility of applying a sphere of spherical polyethylene, a solvent-soluble initiator, to petroleum products, especially motor oil and light fuel oils. Its effect on reducing the freezing point of medium petroleum components is emphasized by affecting the growth and crystalline cracking of solid carbon atoms. The low molecular weight polyethylene is produced by a high pressure process in the production of low density polyethylene. The viscosity numbers of the untreated low-molecular-weight polyethylene range from 0.075 to 0.180, depending on the production of high pressure polyethylene 1 from the solvent used to provide the limit viscosity number. Relative middle mole. the weight of the untreated low molecular weight polyethylene based on the viscosity of the molten polymers is predominantly in the range of about 2,000 to 4,500 units. The low molecular weight polyethylenes of these properties exhibit very good effects and reduce the freezing point of the middle petroleum fractions from paraffinic processes. In some of their species, I can exhibit significant higher moles. weight, which is reflected in their poor solubility. This negative jaw hol observed during the filtering of diesel fuel. Such low molecular weight polyethylenes did not improve the more pronounced filterability, and in some cases deteriorated.

This drawback is avoided by modifying low-molecular-weight polyethylene, separating it from the hydrocarbon-containing higher solubility of higher molecular weight by sedimentation and / or filtration, but preferably by centrifugation using a hydrocarbon solvent from the range of the product to which it is low molecular weight polyethylene should be used, or the solvent may be partially precipitating against higher molecular weight moieties. The advantages of the modified low-molecular-weight polyethylene as a depressant in petroleum products are evident from the following examples without being limited to these examples. EXAMPLE 1 A low molecular weight polyethylene having a limiting viscosity of 0.120 dissolved in 10% hexane as a 10% solution was centrifuged under a Wyroxka MPW-2 centrifuge at 3000 rpm for 15 min. Two layers were created by stripping: the upper — the gill and the lower — the turbid. After separation, the solvent was evaporated. The upper layer contained 79.4% by weight (the lower one and the lower layer was 20.6% by weight (heavier portions) of the divided polyethylene).

The untreated low molecular weight polyethylene, the lighter and heavier portions thereof, were screened as diesel fuel additives. Their effects are shown in Table 1. TABLE 1

Effect of Low-Molecular Polyethylene (NMPE) Centrifugation on Low-Temperature Diesel Oil

Diesel

Pour point ° C

Filtration

% O without additive -17-9 + 0.03% wt. NMPE unadjusted -28-11 + 0.03% wt. NMPE - 1'longer proportions -32 -18 + 0.03% wt. NMPE - heavier shares —26-6

Claims (4)

253442 5 The heavier fractions from the centrifugation of the solution of the cellular polyethylene deteriorate the filterability of diesel fuel, but still have the ability to reduce its solidification temperature. When applied, afco depressant 1'ahikéi oil in the amount of 0.1 wt. lowered the solidification temperature of the flood to +4 qC and -8 ° C. Example 2 From a 14% solution of low molecular weight <polyethylene having a viscosity limit of 0.125 in motor oil, the ALFA LAVAL-LAPX 202 centrifuge was removed at 9,000 rpm and at 10 ° C. The low molecular weight polyethylene solution was used as an additive to motor diesel in an amount of 0.02% calculated on a low molecular weight polyethylene. The non-doped motor oil had a temperature of -14 ° C and a filterability of nosť8 ° C. The addition of said amount of centrifuged molecular weight polyethylene reduces the solidification temperature of the diesel fuel to -26 ° Celsius and the filterability to -10 ° C. Example 3 From the low molecular weight polyethylene of the properties mentioned in Example 1 dissolved in kerosene in the form of a 5% solution, the heavier fractions were separated during long-term storage by settling. The simpler, dissolved solubles used in diesel fuel in the same icon-centering as the untreated low molecular weight polyethylene reduced the filterability of the engine to 0 ° C while the untreated low molecular weight polyethylene was 2 ° C. Example 4 Through the alluvial charcoal filter, saviedol 10% low molecular weight polyethylene in heavy gasoline. The low molecular weight polyethylene had a viscosity viscosity limit of 0.117. Pressure filtration and solvent evaporation afforded a modified molecular polyethylene with a limit viscosity of 0.94, which improved (reduced) the diesel fuel filterability compared to a 6 ° C untreated low molecular weight polyethylene polyethylene. OBJECT OF THE PREFERRED EMBODIMENT A modification of the depressant into low-molecular-weight polyethylene-based petroleum fractions, which is a byproduct of polyethylene produced by high pressure spheres, is dissolved in an initiator solvent of 0.075 and INVENTION 0.180 and a relative mean mole. masses of from 2 to 500 units, characterized in that higher molecular weight molecular weight solutions are removed from its hydrocarbon solutions, insolubles are removed by centrifugation and / or by settling and / or filtration at temperatures below 25 ° C.