Results of the investigation of thermal degradation of polyolefins in the laboratory-scale set-up reactors are presented in the paper. Melting and cracking processes were carried out in two different types of reactors at the temperature of 390-420°C. This article presents the results obtained for conversion of polyolefin waste in a reactor with a stirrer. Next, they were compared with the results obtained for the process carried out in a reactor with a molten metal bed, which was described in a previous publication. For both processes, the final product consisted of a gaseous (2-16 % mass) and a liquid (84-98 % mass) part. No solid product was produced. The light, "gasoline" fraction of the liquid hydrocarbons mixture (C 4 -C 10 ) made up over 50% of the liquid product. The overall (vapor) product may be used for electricity generation and the liquid product for fuel production.

Waste rubber (particularly scrap tires) generated worldwide exerts a detrimental influence on the world economy and the environment. Its fraction in municipal waste amounted to 2% by mass in 2000. By the end of 20 th century, rubber production was about 34 million tons world-wide. It is estimated that 20% of tires have to be recycled every year. Dumping and land filling of used tires were the most popular methods of utilization of them until not long ago. Other alternative methods that have been used for tire recycling such as retreating, reclaiming, incineration and grinding have also significant drawbacks and/or limitations but they influence the environment to a lesser extent than dumping. Pyrolysis or gasification of waste rubber may be the best way of its utilization. The results of the thermal degradation of waste rubber performed in a new type of tubular reactor with molten metal are presented in the paper. The melting and degradation processes were carried out in an apparatus at temperatures of 390-420°C. The problems encountered with the disintegration of wastes, the heat transfer from the wall to the particles, cooking at the walls of the reactor and mixing of the molten volume of wastes are significantly reduced. Two products: gaseous (below ~ 15 weight%) and liquid (over 40 weight%) product were obtained during the degradation of waste rubber. Both streams of products were analyzed by gas chromatography. The gaseous stream contained hydrocarbons from C2 to C 8 and the liquid product consisted of hydrocarbons C 4 to C 24 . Over 80 mol% of liquid hydrocarbons mixture was the fraction C 4 -C 10 . The obtained liquid product may be used in petrochemical and refinery industry or may be recycled for tire manufacturing.

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