ISSN 1070-4272, Russian Journal of Applied Chemistry, 2008, Vol. 81, No. 9, pp. 1630!1633. + Pleiades Publishing, Ltd., 2008.
Original Russian Text + L.V. Furda, I.G. Ryl
tsova, O.E. Lebedeva, 2008, published in Zhurnal Prikladnoi Khimii, 2008, Vol. 81, No. 9, pp. 1555!
AND POLYMERIC MATERIALS
Catalytic Degradation of Polyethylene
in the Presence of Synthetic Aluminosilicates
L. V. Furda, I. G. Ryl
tsova, and O. E. Lebedeva
Belgorod State University, Belgorod, Russia
Received May 26, 2008
Abstract-Degradation of polyethylene in the presence of synthetic amorphous aluminosilicates as catalysts
to form petroleum-like hydrocarbons was studied.
The amount of difficultly degradable industrial
and domestic wastes steadily increases. Large-
tonnage wastes from polyethylene packing materials
are incinerated or disposed of. However, they can be
a valuable secondary raw material for chemical
It is known that thermolysis of polyethylene
yields lower olefins . A wide range of products
which are frequently characterized as petroleum-like
hydrocarbons can be obtained by catalytic degrada-
tion of polyethylene. This process can be catalyzed
by aluminosilicates of different compositions.
Among them, zeolites are used most frequently
Natural aluminosilicates, clays, were proposed to
produce liquid hydrocarbons from polyethylene .
The aim of this study was to determine the fea-
tures of this process in the presence of model cata-
lysts, synthetic aluminosilicates.
It is believed that the reactive components of
a clay catalyst of polyethylene thermolysis are
aluminosilicates. Their catalytic activity depends
on the acidity of the samples. The aluminosilicate
acidity is caused by the presence of aluminum.
Therefore, the catalytic activity of aluminosilicates
of similar structure in polyethylene degradation
should correlate with the aluminum content of
Eight aluminosilicates with different aluminum
contents and hydrated silica sample were prepared.
Since the acidity of aluminosilicates increases with
increasing aluminum content to 13317 wt %, we
studied the catalysts with the aluminum content in
the range including this interval.
Catalysts were prepared by coprecipitation from
solution. An ethanol solution of tetraethoxysilane
(tetraethoxysilane : ethanol weight ratio 1 : 1) was
mixed with a 6% aqueous solution of aluminum
nitrate. An ammonium hydroxide solution was
added to pH 9. The mixture was stirred for 1 h with
a magnetic stirrer and allowed to stand for 24 h to
complete precipitation. The precipitate was filtered
off and calcined in a muffle furnace at 600oC. The
composition and some properties of the catalysts are
presented in Table 1.
The powder X-ray diffraction patterns of the
catalyst samples were recorded on DRON-3 dif-
fractometer using CuK
Table 1. Properties of catalysts
³ Total pore
content, wt %
no. ³³ ³cm
1 ³ 0 ³ 149 ³ 0.6
2 ³ 1.6 ³ 167 ³ 1.0
3 ³ 2.4 ³ 110 ³ 0.5
4 ³ 5.8 ³ 208 ³ 0.9
5 ³ 8.1 ³ 129 ³ 0.6
6 ³ 12.0 ³ 324 ³ 0.8
7 ³ 12.9 ³ 184 ³ 0.9
8 ³ 16.3 ³ 183 ³ 0.9
9 ³ 22.9 ³ 216 ³ 0.8