_________________________________________________________________________DEVELOPMENT OF SOLID ACID CATALYSTS FOR THE CONVERSION OF WASTE
PLASTICS INTO VALUABLE FUEL RANGE HYDROCARBONS
V. Rekha and N. Lingaiah*
Catalysis Laboratory, I&PC Division, Indian Institute of Chemical Technology, Hyderabad-500007, India
Email: nakkalingaiah@iict.res.in*Corresponding author. Tel.: +91 40 2719 1722; fax: +91 40 2716 0921______________________________________________________________________________________________________Abstract
The catalytic degradation of waste plastics is carried for the production of potentially valuable hydrocarbons. Alumina-silica
based mixed oxide catalysts were prepared and studied for the conversion of waste plastic into fuel oil. The results suggest thatthe catalysts are highly efficient compared to commercial catalysts. The catalyst is cheap, easy to prepare and reproducible inlarge quantities.

______________________________________________________________________________
Keywords: Waste plastics; alumina-Silica catalyst; degradation; fuel oil.

1. Introduction
In recent years the use of plastics increased dramatically and at the same time more waste plastics coming out with widespread
applications of plastics. As the most of these waste plastics are non-degradable under natural conditions, it becomes a serious
environmental problem. It is necessary to attend this problem of environment and at the same time it is important to utilize theprecious carbon source. There are different method in treating the waste plastics such as land filling, incineration, and thermal
cracking. Generally thermal cracking can be carried with the aid of a catalyst to get the refined useful products. Numerous
papers present the application of various acidic catalysts, such as silica–alumina, zeolites (HY, HZSM-5, mordenite) or othermetal oxides [1-4].The present study related to the development of alumina-silica based catalysts for the conversion of waste
plastics collected from municipality.

2. Experimental
Alumina-silica based mixed oxides catalysts were prepared by using physical mixing method. The caalysts were calcinated in air
from 400 - 900°C. The catalysts were characterized by BET surface area , X-ray diffraction and temperature programmeddesorption of ammonia. The catalysts were evaluated for the conversion of waste plastic into fuel range hydrocarbons.

3. Results and Discussion
The catalytic activities of alumina-silica based catalysts were evaluated for the conversion of waste plastic into fuel range
hydrocarbons and the results are presented in Table1. The activity is explained based on the physico-chemical properties of thecatalysts. The results suggest that the catalysts are highly active for the complete conversion of waste plastics with 12-16 min ofreaction time. The overall efficiency of the system in conversion of plastics is above 90%. The activity of the catalysts is related
to its controlled acidic properties. The results were discussed based on the surface and structural features of the catalysts.

7th International Symposium on Feedstock Recycling of Polymeric Materials (7th ISFR 2013)
New Delhi, India, 23-26 October 2013

Table 1. Activity profile during catalytic degradation of waste plastics

Quantity ofPlastic (g)Catalyst
amount (%)

Reaction
Temperature

Total output
time (min)Quantity ofoil (ml)Density ofoil (g/ml)

Efficiency of thesystem (%)(°C)

5000.2530

12450

0.78

90

500

0.5529

11475

0.78

95500

1532

134600.7692500

1.5530164250.78

85

4. Conclusions
Alumina-silica based mixed oxide catalysts are active for the conversion of waste plastic into fuels. The catalysts are efficiently
converting plastics into oil with very small amount of catalyst. Preparations of these catalysts are relatively easy, reproducible
and also cheap.

References[1] Y. Uemichi, M. Hattori, T. Itoh, J. Nakamura, M. Sugioka, Ind. Eng. Chem. Res. 37 (1998) 867– 872.
[2] W. Ding, L. Liang, L.L. Anderson, Fuel Process. Technol. 51 (1997) 47–62.
[3] Z. Zhibo, S. Nishio, Y. Morioka, A. Ueno, H. Ohkita, Y. Tochihara, Catal. Today 29 (1996) 303– 308.
[4] S. Kargfz, T. Karayildirim, S. Ucar, M. Yuksel, J. Yanik, Fuel 82 (4) (2003) 415– 423.

7th International Symposium on Feedstock Recycling of Polymeric Materials (7th ISFR 2013)
New Delhi, India, 23-26 October 2013