Degradation of waste High-density polyethylene into fuel oil using basic catalyst M. Rasul Jan, Jasmin Shah * , Hussain Gulab Institute of Chemical Sciences, University of Peshawar, N.W.F.P., Pakistan article info Article history: Received 1 September 2008 Received in revised form 9 September 2009 Accepted 10 September 2009 Available online 25 September 2009 Keywords: Basic catalyst Catalytic degradation HDPE Hydrocarbons abstract High-density polyethylene (HDPE) has been degraded thermally and catalytically using MgCO 3 at 450 °C into liquid fraction in a batch reactor. Different conditions like temperature, time and catalyst ratio were optimized for the maximum conversion of HDPE into liquid fraction. Catalytic degradation yielded 92% liquid fraction whereas 90% wax was obtained with thermal degradation. The composition of the liquid fraction was characterized by physicochemical properties of petroleum fuel tests. The catalytic liquid fraction consisted of high concentration of C 8 –C 9 ,C 13 –C 14 and C 17 –C 18 hydrocarbons. The distillation data showed that 50% of the fraction has boiling point in the range of gasoline and 50% in the range of die- sel oil. Ó 2009 Elsevier Ltd. All rights reserved. 1. Introduction Management of plastic wastes is a hot issue and currently about 90% of the plastic wastes are disposed in landfills and incineration, but both these applications are not environmental friendly and cre- ate other problems [1]. To avoid environmental problem and use plastic waste as a resource, alternative solutions are needed. It can be converted into useful products for resource recovery. To overcome the current energy crises in the world, new energy re- sources should be explored among which waste high-density poly- ethylene could be used as raw material. One of the possible solutions is thermal/catalytic degradation of the plastic materials to obtain a useful and selective degradation product like fuel oil and laboratory chemicals [2]. Various options have been exploited for the conversion of waste plastic into useful liquid products [3–5]. Recently efforts have been focused on the yield and quality of the liquid product obtained by catalytic degradation of HDPE using different catalyst [6–9]. Neves et al. [10] studied the impact of an aluminosilicate catalyst on the degradation product of the catalytic conversion of HDPE using TGA technique. Mastral et al. [11] and Luo et al. [12] degraded HDPE thermally and catalytically in a fluidized bed reactor focusing on the gaseous product and composition of liquid/gaseous product, respectively. Miskolczia et al. [13] investigated the effect of FCC, HZSM-5 and clinoptilolite catalysts on the degradation process of HDPE. They found a decrease in the liquid yield for different cata- lytic reactions in order of FCC > clinoptilolite > HZSM-5. Ji et al. [14] pyrolysed low density polyethylene at high temperature in the presence of metal salts and observed an increase in the formation of aromatics with increase in the temperature. Mosio-Mosiewski et al. [15] used an autoclave for the cracking of LDPE applying alu- minosilicate, alumina and Ni–Mo/Al 2 O 3 catalysts and compared the reaction products in respect of aromaticity, saturation and un-saturation. Azharuddin et al. [16] catalytically degraded HDPE, LDPE, linear LDPE and cross-linked PE using silica–alumina as a catalyst and investigated the effect of the catalyst on the yield and distribution of the liquid product. In the present study a basic and easily available catalyst (MgCO 3 ) has been explored for the cat- alytic pyrolysis of HDPE. The product obtained were characterized and compared with different grades of standard fuel oil. 2. Experimental 2.1. Materials and methods Municipal waste high-density polyethylene bottles were cut into pieces of 5–10 mm 2 sizes that were used as a feed for the deg- radation process. For optimization study, 5 g sample was taken for every triplicate experiment. For collection of large volume of liquid sample the amount of the sample taken was 200 g. Powdered MgCO 3 having particle size 100 lm was used as a basic catalyst for the catalytic degradation reaction. The degradation reaction was carried out in a batch Pyrex glass reactor with height; 22 cm, i.d.; 70 mm and wall thickness of 2.4 mm. A fixed amount of HDPE sample and catalyst was taken in the pre-weighed reactor and placed in a specially designed electrical furnace. The glass reactor containing the sample was heated at a heating rate of 40 °C/min with the help of the electrical furnace monitored by a 0016-2361/$ - see front matter Ó 2009 Elsevier Ltd. All rights reserved. doi:10.1016/j.fuel.2009.09.007 * Corresponding author. Tel./fax: +92 91 9216652. E-mail addresses: rasuljan@yahoo.com (M.R. Jan), jasminshah2001@yahoo.com (J. Shah). Fuel 89 (2010) 474–480 Contents lists available at ScienceDirect Fuel journal homepage: www.elsevier.com/locate/fuel