Microwave Pyrolysis of C6 Non-aromatic Hydrocarbons
Apple Jamjumras and Suksun Amornraksa
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Department of Mechanical and Process Engineering, The Sirindthorn International Thai-German Graduate
School of Engineering, King Mongkut’s University of Technology North Bangkok, Thailand
Abstract. C6 non-aromatic hydrocarbons obtained from olefins plant was used as a feedstock in
microwave pyrolysis. The experiment was carried out in a microwave reactor over an activated carbon,
which acts as a microwave receptor. Operating temperature (from 500 to 700 ºC), controlled by power of
microwave reactor, was varied to observe the consequence on the pyrolysis products. The chemical
composition and product yield of the pyrolysis products (liquid oil and gas) were analyzed by using gas
chromatography/mass spectrometry (GC/MS). The results indicated that microwave pyrolysis has the
potential to upgrade low value hydrocarbons into high value products. The recovered liquid and gaseous
pyrolysis products contained various hydrocarbons which could be used as a valuable industrial feedstock.
Keywords: Microwave, Microwave Pyrolysis, C6 Non-aromatic, Hydrocarbons.
1. Introduction
Chemical industries have rapidly grown up, especially petrochemical industry. The products derived
from the petrochemical industry are generally used as a raw material for many downstream industries to
supply the increasing demand for synthetic products and daily life products. Hydrocarbons such as LPG,
naphtha, and condensate, are typically used as raw material in the upstream petrochemical industry where
olefins products such as ethylene and propylene are produced. Pyrolysis is conventionally and widely used as
a thermal conversion process to convert the hydrocarbons feed into the olefins products [1, 2]. The process,
also known as thermal cracking, takes place at a high temperature in the absence of oxygen. After passing a
pyrolysis chamber, heavy hydrocarbons feed will be broken down into lighter molecules. In addition to the
olefins products, several mixed hydrocarbon by-products are also produced. Some of these by-products are
normally separated and sold to other users at low price. Often, they are sent back to the pyrolysis chamber as
a recycle stream.
Due to the strong competitiveness of petrochemical business, the utilization of by-products from the
manufacture is very crucial. It is more desirable to upgrade by-products by turning them into more valuable
products rather than being used as the recycle stream. Furthermore, in the conventional pyrolysis, there is
large amount of energy losses during the heat transfer from a heat source to the raw material in the pyrolysis
chamber. Also, the pyrolysis can promote undesired by-products. According to energy concern and recent
pollution problems, novel production technologies that are more efficient, consume less energy, and able to
upgrade the low-valued products have been substantially sought and developed.
Microwave pyrolysis is a relatively new technique which provides many advantages over conventional
pyrolysis process. It is extremely efficient method in selective heating of materials as the energy can be
transferred directly to the material [2, 3, 4]. This results in less energy consumption, process time saving and
more environmental friendly. In addition, the use of microwave in hydrocarbon conversion has a high
potential to produce new hydrocarbon products and also reduce unwanted side reaction that usually occurs in
the conventional processes. In recent years, the use of microwave pyrolysis has been employed in the
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Corresponding author. Tel.: + 66 (0)2 555 2000 Ext.2928.
E-mail address: suksuna@kmutnb.ac.th
2012 4th International Conference on Chemical, Biological and Environmental Engineering
IPCBEE vol.43 (2012) © (2012) IACSIT Press, Singapore
DOI: 10.7763/IPCBEE. 2012. V43. 6
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