WO1996001298A1

WO1996001298A1 - The method of obtaining liquid fuels from polyolefins wastes

Info

Publication number: WO1996001298A1
Application number: PCT/PL1995/000009
Authority: WO
Inventors: Henryk Zmuda
Original assignee: Dynamic Structures Corp. S.A.
Priority date: 1994-07-01
Filing date: 1995-05-30
Publication date: 1996-01-18
Also published as: AU2457195A

Abstract

The subject of the invention is a method of obtaining liquid fuels form the polyolefins waste, and also from the used products made of polyethylene, polypropylene, polystyrene and other polyolefins. The polyolefin raw materials are degradated in a purely thermic way in the temperatures between 500-600 °C or the catalysts are introduced into the system in the form of aluminium oxide, aluminium silicate or aluminosilicates of alkali metals or alkali earth metals, particularly profitable as aluminium silicate, in amount of 1-5 % by weight and the mixture is heated in the temperatures between 400-600 °C. Profitably, during the reaction the air can be introduced into a system in amount of 0,02 to 0,04 m3 per 1 kg of the proceeded mixture. The obtained petrol type or diesel oil type fuels have good anti-knock properties for the use in internal combustion engines.

Description

The method of obtaining liquid fuels from polyolefins wastes The subject of the invention is the method of obtaining liquid fuels from the polyolefines waste, and also from the used products made of polyethylene, polypropylene, polystyrene and other polyolefines.

Generally, the economical and ecological problem of the reasonable utiliza¬ tion of a big amounts of isotactical polypropylene wastes, as well as poly¬ ethylene, polystyrene and poly/methyl metacrylate/, for instance from the packings, containers, used agricultural foils, electrotechnical and medical details and the remains of an organic glass.

Full recycling of the above mentioned materials, desired for many reasons, is limited because of the loss of the utilitary properties of polymers, for example as it happens in a case of the used agricultural foils. It is known, that the macromolecular types of polyolefines, and partially al¬ so polydienes, heated in the range of the higher temperatures undergo the termodegradation, giving a mixture of the liquid products, being the conglo¬ merate of the different types hydrocarbons. To this group belong alkanes, isoalkanes, olefines, naphtenes and aromatic compounds, which can be used as the row materials for the fuel mixture compositions.

However the termodegradation of macromolecular polyofefines goes more difficultly than the termodegradation of atactical polypropylene, since it needs, for instance, longer heating period and relatively higher temperatu¬ res. From the Polish patent description no 149887 there is known a method of the termical degradation of atactical polypropylene to the liquid hydrocar¬ bons, where the milled polymer is heated in the temperatures between 130 - 340°C in a presence of air. Approximately a half of the obtained product amounted of the petrol fraction, and the rest - diesel oil fraction. The substance of the method according to the invention consists on a fact, that to the mixture of polyolefines the catalysts are introduced in a form of aluminium oxide, aluminosilicates of alkali metals or aluminosilicates of alkaline earth metals, preferably aluminium silicate in amount of 1-5% by weight and the proces is run in the temperatures between 400-500°C. The catalytic method, according to the invention allows to decrease the tempe- ratures for 100°-200°C and to improve the quality of the obtained fuels in the range of their anti-knock properties.

Particularly profitable economical and productiv results are obtained, when simoultaneously to the catalysed system the air has been introduced in the amount of 0,02 - 0,04 m³ per 1 kg of the proceeded material. The introduc- tion of such a small amount of the air accelerates the proces and at the same time increases the yield of the distillates in the result of a partial change of their chemical nature, which phenomena is related to the creation of alco¬ hols and ketones next to the hydrocarbons.

Example 1. The milled polyolefines wastes with the addition of aluminium silicate in amount of 3% by weight were heated in the temperature of 450°C. The vapours of the generated products of a destruction of macromolecules were carried away through the condenser to a tank. The total yield of a con¬ densate reached 98% theoretical. The raw condensate was distilled once mo¬ re and the fractions of petrol and diesel oil had been separated. The petrol obtained in a method according to the invention showed the octane number of 85 and a diesel oil fraction had a cetyl number of 80.

Example 2. To the milled polyolefines waste a catalyst in the form of alumi¬ nium oxide had been added in amount of 4,5% by weight of the polyolefines. This mixture had been heated in the reaction retort up to about 450°C, in- troducing simultaneously the air into the melted polymers in amount of 0,03 m³ per every kilogramm of a charge. The vapours of the termodegradation products, condensed in the tank, gave the liquid hydrocarbones with the yield of 98,5% theoretical.

Claims

Patent claims

1. The method of obtaining liquid fuels from polyolefines waste in the way of a termodegradation process, distinctive from others, that the process is realized in a purely thermal way or to the degradated polyolefines mixtu¬ re the catalysts are introduced in the form of aluminium oxide, aluminium silicate, aluminosilicates of alkali metals or alkaline earth metals, parti¬ cularly profitable as aluminium silicate, in amount of from 1 to 5 % by weight and the mixture is heated in the temperatures from 400°C to 600°C.

2. The method according to the claim 1, distinctive from others, that during the process of a normal or catalytic termodegradation the air is introdu¬ ced into a system in amount of from 0,02 to 0,04 m³ per 1 kg of the pro¬ ceeded material.