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  1. 1. Satyendra Singh Tomar, Dr.S.P.Singh / International Journal of Engineering Research and Applications (IJERA) ISSN: 2248-9622 Vol. 3, Issue 2, March -April 2013, pp.340-347Regaining Of Hydrocarbon Liquids From Discarded Polyethylene By Thermolysis In Semi Batch Reactor Satyendra Singh Tomar, Dr.S.P.Singh Department of Chemical Engineering, BIT, Sindri, Jharkhand, 828123Abstract Thermolysis of waste plastics in an inert Recycling of plastics already occurs on a wide scale.atmosphere has been gazed at as a useful method, Extensive recycling and reprocessing of plastics arebecause this technique can convert waste plastics performed on homogeneous and contaminant freeinto hydrocarbons that can be used either as fuels plastic wastes. Most recycling schemes require aor as other valued chemicals. In this work, waste feedstock that is reasonably pure and contains onlypolyethylene (PE) was chosen as the raw material items made from a single polymer type, such asfor thermolysis. A well designed semi batch Polyethylene (PE) commonly used to make milkreactor has been used for thermolysis of waste bottles, or polyethylene terephthalate (PET) softpolyethylene (PE) with the objective of enhancing drink bottles. However, a substantial fraction ofthe liquid product yield at a temperature range of theplastics in municipal waste still ends up in350ºC to 500ºC. Results of thermolysis landfills. Realistically, most post-consumer wastesexperiments showed that, at a temperature of contain a mixture of plastic types and are often400ºC and below the major product of the contaminated with non-plastic items (Hegberg et al.,thermolysis was oily liquid which became a 1992)[3].viscous liquid or waxy solid at temperaturesabove 425ºC. The yield of the liquid fraction An alternative thermal approach for dealingobtained increased with the residence time for with waste plastics is the so-called chemicalwaste polyethylene (PE). The oily liquid fractions feedstock or chemical recycling. This term has beenobtained were examined for composition using used to describe a diversity of techniquesFTIR and GC-MS. The physical properties of the includingthermolysis, hydrolysis, hydrogenation,thermolytic oil show the presence of a mixture of methanolysis and gasification. Some of thesedifferent fuel fractions such as gasoline, kerosene techniques are suitable for use only withand diesel in the oil. homogeneous polymer wastes but others can accept a feed of mixed wastes.Keywords: Thermolysis;PE; FTIR; GCMS;liquid fuel. The most attractive technique of chemical feedstock recycling is thermolysis. Thermal crackingINTRODUCTION or thermolysis involves the degradation of the Plasticsareone ofthe mostwidelyused polymeric materials by heating in the absence ofmaterials due to their variousadvantagesand oxygen. Unlike mechanical recycling techniques, innumerous applicationsin ourday-to-day life. Plastics which the long polymeric chains of the plastic areproduction has increased by an average of almost preserved intact, thermolysis produces lower10% every year on a global basis since 1950. The molecular weight fragments. The process is usuallytotal global production of plastics has grown from conducted at high temperature and results in thearound 1.3 million tons (MT) in 1950 to 230 MT in formation of a carbonized char and a volatile2009 (Plastic-The facts 2010). PE is the third largest fraction that can be separated into condensablecommodity plastic material in the world, after hydrocarbon oil and a non-condensable highpolyvinyl chloride and polypropylene in terms of calorific value gas. The proportion of each fractionvolume. According to aBritish market-research and their precise composition depend primarily onconsulting agency, “Merchant Research & the nature of the plastic waste, but also on processConsulting Ltd”.Polyethylene (PE) has accounted conditions. The effect of temperature and the type offor a major share of ethylene consumption in the reactor on the pyrolysis of waste PE studied byrecent years. The demand for PE has increased 4.4% different researchers are summarized below.a year to 31.3 million MT in 2009 (CEH report) [1]. Wallis et al. (2007) performed the thermalThe treatment of waste plastics has become a serious degradation of polyethylene in a reactive extruder atproblem and the pyrolysis (thermolysis) of these various screw speeds with reaction temperatures ofmaterials can be one of the most suitable processes 400°C and 425°C[4]. A continuous kinetic model wasfor upgrading them [2]. used to describe the degradation of the high density polyethylene in the reactive extruder. 340 | P a g e
  2. 2. Satyendra Singh Tomar, Dr.S.P.Singh / International Journal of Engineering Research and Applications (IJERA) ISSN: 2248-9622 Vol. 3, Issue 2, March -April 2013, pp.340-347Conesa et al. (1994) studied the production of gases in a stirred semi batch reactor on a laboratoryfrom polyethylene at five nominal temperatures scale was studied by Lee et al. (2003)[12]. As(ranging from 500°C to 900°C) using a fluidized compared with thermal degradation, the catalyticsand bed reactor. From the study of HDPE pyrolysis degradation showed an increase of liquid yield,in a fluidized sand bed reactor, they have found that whereas that of residue was reduced due to thethe yield of total gas obtained increased in the range decomposition of heavier residues into lighter oil500-800°C from 5.7 to 94.5%, at higher product.temperatures[5]. Singh K.K.K. et al., reported maximum yield of liquid when polymer catalyst ratio was 4:1 and after Walendziewski et al. (2001) reported the this ratio the liquid yield decreases. The degradationthermal degradation of polyethylene in the of waste plastic was over two commercial gradetemperature range 370-450°C. In the case of thermal cracking catalysts, HZY (20) & HZY (40) in a semi-degradation of polyethylene, an increase in batch reactor [13].degradation temperature led to an increase of gasand liquid products, but a decrease of residue Seo et al. (2003) studied the catalytic(boiling point >360°C)[6]. degradation of waste high density polyethylene toThe thermal degradation of waste PE can be hydrocarbons by ZSM-5, zeolite-Y, mordenite andimproved by using suitable catalysts in order to amorphous silica-alumina in a batch reactor andobtain valuable products. The most common investigated the cracking efficiency of catalysts bycatalysts used in this process are: zeolite, alumina, analyzing the oily products, including paraffins,silica-alumina, FCC catalyst, reforming catalyst etc. olefins, naphthenes and aromatics, with gasThe effects of various catalysts on the pyrolysis of chromatography/mass spectrometry (GC/MS)[14].PE studied by different investigators are summarizedbelow. The liquid-phase catalytic degradation of HDPE over BEA, FAU, MWW, MOR and MFI Beltrame et al. (1989) have studied zeolites with different pores in a batch reactor atpolyethylene degradation over silica, alumina, silica- 380°C or 410°C has been studied by Park et al.alumina and zeolites in small Pyrex vessel reactor (2002)[15].without stirring, in the temperature range 200–600°C[7]. Manos et al. (2000) studied the catalytic degradation of high-density polyethylene to The catalytic upgrading of the pyrolysis hydrocarbons over different zeolites[16]. The productgases derived from the pyrolysis of polyethylene range was typically between C3 and C15over zeolite in the temperature range 400–600°C has hydrocarbons.been investigated by Bagri et al. (2002)[8]. The catalytic pyrolysis of high density As the zeolite bed temperature was polyethylene was studied at different times usingincreased, the gas yield increased with a decrease in different types of reactors: a pyro-probe apparatus,oil and coke yield. Venuto et al. (1979) also showed where the volatile residence time is in the range ofthat, as the catalyst temperature was increased from few milliseconds, and a fluidized bed reactor, where480 to 590°C, coke formation in the zeolite catalytic the secondary reactions take place to a larger extentcracking of petroleum was reduced and also alkene using HZSM-5 catalyst (Hernandez et al., 2006)[17].gases increased in the gas product[9]. Garforth et al. (1998)[18]studied the catalytic Sharratt et al. (1997) carried out the pyrolysis of polyethylene in a laboratory fluidizedcatalytic degradation of polyethylene using ZSM-5 bed reactor operating in the 290°C-430°C rangezeolite. As the reaction temperature was increased under atmospheric pressure. The catalysts used werefrom 290 to 430°C, the gas yield was increased, HZSM-5, Silicalite, HMOR, HUSY and SAHA andwhereas the oil yield was decreased[10]. the yield of volatile hydrocarbons (based on the feed) was HZSM5>HUSY≈HMOR>SAHA. Oil obtained in the thermolysis ofpolyethylene contained a low concentration of The catalytic degradation of high densityaromatic compounds. The liquid-phase catalytic polyethylene (HDPE) under nitrogen using adegradation of waste polyolefin polymers such as laboratory fluidized bed reactor operating at 360°CHDPE, LDPE, and PP over spent fluid catalytic with a catalyst to polymer feed ratio of 2:1 and atcracking (FCC) catalyst was carried out at 450°C with a catalyst to polymer feed ratio of 6:1atmospheric pressure in a stirred semibatch under atmospheric pressure using ZSM-5, US-Y,operation by Lee et al. (2003)[11].The difference in ASA, fresh FCC (fluid catalytic cracking)the product yields between thermal and catalytic commercial catalyst (Cat-A) and equilibrium FCCdegradation of waste PE using spent FCC catalyst catalysts with different levels of metal poisoning 341 | P a g e
  3. 3. Satyendra Singh Tomar, Dr.S.P.Singh / International Journal of Engineering Research and Applications (IJERA) ISSN: 2248-9622 Vol. 3, Issue 2, March -April 2013, pp.340-347were studied (Ali et al., 2002)[19]. the condenser and weighed. After thermolysis, the Mastral et al. (2006) studied the catalytic solid residue left inside the reactor was weighed.degradation of high density polyethylene in a Then the weight of gaseous/volatile product waslaboratory fluidized bed reactor at mild calculated from the material balance. Thetemperatures, between 350°C and 550°C[20]. The uncondensed gases were separated out in a bladdercatalyst used was nanocrystalline HZSM-5 zeolite. from condenser. Apparatus setup and samples collected for testing are shown in Figure. 1(a,b) Lin et al. (2004) studied the pyrolysis ofpolyethylene over various catalysts using a Reactions were carried out at differentlaboratory fluidized-bed reactor operating temperatures ranging from 350-500°C. FTIR of theisothermally at ambient pressure[21]. thermolysis oil obtained at the optimum conditionKaragoz et al. (2003) studied the conversion of high was performed and the product wasalso analyzed bydensity polyethylene in vacuum to fuels in the GC-MS using flame ionization detector.absence and presence of five kinds of metalssupported on active carbon catalysts (M-Ac) and 2. RESULTS AND DISCUSSIONacidic catalysts {HZSM-5 and DHC (Distillate 3.1 Proximate &Ultimate Analysis of Waste PEHydro Cracking- 8)} catalyst[22]. The proximate and ultimate analyses of waste PE sample are shown in Table 1. The Jan et al. (2010) studied the degradation of volatile matter is 100% in the proximate analysis,waste high density polyethylene into a liquid due to the absence of ash in waste polyethylenefraction thermally and catalytically using MgCO3 at sample; its degradation occurs with minimal450°C in a batch reactor [23]. formation of residue. The oxygen is 5.19% in theDifferent conditions like temperature, time and ultimate analysis of waste polyethylene. The oxygencatalyst ratio were optimized for the maximum in the waste polyethylene sample may not be due toconversion of polyethylene into a liquid fraction. In the fillers but rather to other ingredients that arethe present study, waste polyethylene was added to the resin in the manufacturing ofthermolized in a semi-batch reactor at a temperature polyethylene.of 350°C to 500°C at a heating rate of 20°C/min.The effect of thermolytic temperature and holding 3.2 TGA &DTG Analysis of the Waste PEtime on the reaction time and yield of liquid product, Samplechar, and gaseous product were studied. The fuel Thermogravimetric analysis (TGA) is aproperties of the oil (obtained at a temperature of thermal analysis technique that measures the weight400°C from thermolysis of waste PE such as change of a material as a function of temperaturekinematic viscosity, flash point, fire point, cloud and time, in a controlled environment. This can bepoint, pour point, specific gravity, and water content very useful to investigate the thermal stability of awere determined using standard test methods. The material, or to investigate its behavior in differentchemical compositions of the waste PE thermolytic atmospheres.oil were investigated using FTIRand GC/MS. TGA was applied to study the thermal 1. MATERIALS AND METHODS stability/degradation of waste PE in various ranges Waste Polyethylene was collected from the of temperature. From the TGA curve shown inBITSindri, Dhanbad,Jharkhand, India campus waste Figure 2, the waste polyethylene degradation startedyard and used in this experiment. The catalytic at 340°C and was complete at 440°C for a heatingthermolysis of polyethelene was carried out in a rate of 20°C min. the degradation temperature atsemi-batch reactor. The thermolysis setup used in which a weight loss of 50% (T50) takes placethis experiment is shown in Figure 1. It consists of a was about 390°C for waste PE. The differentialsemi batch reactor (steel made) of volume 2 liters, thermogravimetry (DTG) curve for waste PE invacuum-packed with two outlet tubes towards Figure 3 contains only one peak, this indicates thatvacuum pump and condenser. Vacuum pump with a there is only one degradation step in the dominantgage is attached to the reactor so as carryout the peak from 330°C to 420°C where the conversionreaction in vacuum. The condenser is attached to takes place.collect condensed Liquid hydrocarbons and gasesseparately. The reactor is heated externally by an 3.3 Effect of Temperature on Productelectric furnace, with the temperature being Distributionmeasured by a Cr-Al: K type thermocouple fixed Thermolysis of PE yielded four differentinside the reactor, and temperature is controlled by products, i.e., oil, wax, gas, and residue. Thean external controller. 100 gm of waste plastics distributions of these fractions are different atsample was loaded in each thermolysis reaction. The different temperatures and are shown in Table 2.condensable liquid products was collected through The condensable oil/wax and the non-condensable 342 | P a g e
  4. 4. Satyendra Singh Tomar, Dr.S.P.Singh / International Journal of Engineering Research and Applications (IJERA) ISSN: 2248-9622 Vol. 3, Issue 2, March -April 2013, pp.340-347gas/volatiles fractions of the reaction constituted the oil, chemical bonds can absorb infrared radiation inmajor product as compared to the solid residue specific wavelength ranges regardless of thefractions. The condensable product obtained at low structure of the rest of the molecules Figure 6 showstemperature (350°C and 400°C) was low viscous the FTIR spectra of waste PE oil. The differentliquid. With an increase in temperature, the liquid assignments of the FTIR spectra of waste PE oil arebecame a viscous/wax at and above 425°C. The summarized in Table 3, which shows the presence offormation of a viscous and waxy product was due to mostly alkanes and alkenes. The results wereimproper cracking of the plastic to high molecular consistent with the results of GC-MS.mass hydrocarbon components. The recovery of thecondensable fraction was very low at low .3.7 GC-MS of the Oil Sampletemperature, i.e., at 350°C, and increased with a The GC-MS analysis of the oil samplegradual increase of temperature. obtained from waste PE was carried out to verify the exact composition of the oil (Figure 7) and is From the table, it is observed that, at low summarized in the Table 4. The components presenttemperature, the reaction time was longer, due to in PE are mostly aliphatic hydrocarbons (alkane andsecondary cracking of the thermolysis product that alkenes) with carbon number C9-C24.occurred inside the reactor, which resulted in highlyvolatile product. Similarly, the low liquid yield at 3.7 Physical Properties of the Oil Samplehigh temperature was due to the formation of less- Table. 5 shows the results of physicalcracked high molecular weight wax and more non- property analysis of the oil obtained fromcondensable gaseous/volatile fractions due to thermolysis of waste PE. The appearance of the oil isrigorous cracking. dark brownish free from visible sediments. From the distillation report of the oil it is observed that the3.4 Effect of Temperature on Reaction Time boiling range of the oil is 82-352°C, which suggests The effect of temperature on the reaction the presence of a mixture of different oil componentstime for the thermolysis of waste Polyethylene is such as gasoline, kerosene and diesel in the oil. Theshown in Figure 4. The thermolysis reaction rate oil obtained from the thermolysis was fractionated toincreased and the reaction time decreased with an two fractions by distillation and the fuel propertiesincrease in temperature. High temperature supports of the different fractions were studied. From thisthe easy cleavage of bonds and thus speeds up the result, it is observed that the fuel properties ofreaction and lowers the reaction time. PE, with a thethermal thermolysis oil match the properties oflong linear polymer chain with low branching and a petroleum fuels.high degree of crystallinity, led to high strengthproperties and thus required more time fordecomposition. This shows that temperature has asignificant effect on reaction time and yield ofliquid, wax and gaseous products.3.5 Effect of Holding Time on Yield of Oil The effect of holding time on the yield ofthe oil is shown in Figure 5. The reaction wascarried out by keeping the plastics in the reactor at350°C with different holding times from 1-6 hours,followed by an increase of the reaction temp to400°C. It was observed that this additional reactionphase increased the oil yield from 23% to 28% for a1 hour holding time and to 50.8% with a 4 hourholding time, but then decreased gradually with Figure. 1(a) Apparatus setupfurther increase in the holding time. The introductionof this reaction phase loosens the polymer bonds thatare easily cleaved to liquid hydrocarbons, whichleave the outlet at 400°C without being converted togas due to the decrease in reaction time compared to350°C.3.6 FTIR of Oil Samples Fourier Transform Infrared spectroscopy(FTIR) is an important analysis technique thatdetects various characteristic functional groupspresent in oil. Upon interaction of infrared light with Figure. 1(b) Samples collected for testing 343 | P a g e
  5. 5. Satyendra Singh Tomar, Dr.S.P.Singh / International Journal of Engineering Research and Applications (IJERA) ISSN: 2248-9622 Vol. 3, Issue 2, March -April 2013, pp.340-347 Figure 5: Effect of holding time on the yield.Figure 2: TGA curve of waste polyethylene Figure 6: FTIR spectrum of waste PE oil obtained at 400°C.Figure 3: DTG curve of waste polyethyleneFigure 4: Effect of Temperature on Reaction Time 344 | P a g e
  6. 6. Satyendra Singh Tomar, Dr.S.P.Singh / International Journal of Engineering Research and Applications (IJERA) ISSN: 2248-9622 Vol. 3, Issue 2, March -April 2013, pp.340-347Figure 7: GC/MS chromatogram of the oil that wasobtained at 400°C R.Time Area Name of Molecul (min) % Compound ar Properties Present (Parikh (Kim et Formula study et al., al., 3.050 1.50 1-Nonene C9H18 (Waste 2009) 2010) 3.147 0.96 Nonane C9H20 PE) [24] [25] 4.465 2.60 1-Decene C10H20 Proximate analysis 4.463 1.25 Decane C10H22 Moisture 0.00 0.00 1.37 5.914 3.22 1-Undecene C11H22 content 6.116 1.76 Undecane C11H24 Vol. matter 100 100 92.90 7.525 3.30 1-Dodecene C12H24 Fixed carbon 0.00 0.00 1.14 7.628 2.25 Dodecane C12H26 Ash content 0.00 0.00 4.59 8.960 3.80 1-Tridecene C13H26 Ultimate Analysis 9.075 2.50 Tridecane C13H28 Carbon 80.50 84.95 79.9 10.346 4.70 1-Tetradecene C14H28 Hydrogen 13.90 14.30 12.6 10.450 2.90 Tetradecane C14H30 Nitrogen 0.60 0.55 - 11.618 4.87 1-Pentadecene C15H30 Sulphur 0.080 - - 11.714 3.18 Pentadecane C15H32 Oxygen 5.35 0.20 5.10 12.846 5.09 1-Octadecene C18H36 Chlorine - - 1.13 12.935 3.68 Hexadecane C16H34 GCV 45.78 - 44.40 14.011 4.87 1-Heptadecene C17H34 (Mj/Kg) 14.084 3.70 Hexadecane C16H34 15.096 4.70 1-Nonadecene C19H38 15.170 369 Hexadeane C16H34Table 1: Proximate and ultimate analysis of waste 16.135 4.40 1-Nonadecene C19H38polyethylene 16.211 3.68 Hexadecane C16H34 17.145 3.76 1-Nonadecene C19H38 17.190 3.19 Eicosane C20H42 Temp (°C) 350 400 450 500 18.079 3.17 1-Nonadecene C19H38 Oil (wt.%) 11.2 23.8 21.9 7.9 2.97 Heneicosane C21H44 18.139 Wax (wt.%) 0 0 50.0 71.1 18.995 2.55 1-Nonadecene C19H38 Gas/ volatile 84.2 72.4 25.1 18.5 19.047 2.47 Docosane C22H46 (wt.%) 19.859 1.99 1-Nonadecene C19H38 Residue(wt.%) 4.6 3.8 3.0 2.5 19.920 1.99 Tricosane C23H48 Reaction time 760 290 68 54 20.687 1.27 1-Nonadecene C19H38 (min) 20.751 1.28 Tetracosane C24H50 21.501 0.94 1-Nonadecene C19H38Table 2: Distribution of the different fractions at 21.538 0.69 Docosane C22H46different temperatures in the Polyethylene 22.274 0.44 n-Tetracosanol-1 C24H50Othermolysis 22.310 0.36 Tetracosane C24H50 23.015 0.27 1-Nonadecene C19H38 Wave Type of Name of 25.051 0.21 4,6- C14H30 Number Vibration Functional Dimethyldodecane (cm-1) group 2955/296 C-H stretching Alkane 6 1373 C-H Scissoring Alkane and Binding 2851 C-H stretching Alkane 1642 C=H stretching Alkane/Fingerpr int region 1462 C=H stretching Alkane/Fingerpr int region 991 C-H Bending Alkane 908 C-H Out-of- Alkane plane bending 720 C-H Bending Alkanes BandsTable 3: FTIR assignments of waste PE oil obtainedat 400°C Table 4: GC-MS composition of oil obtained at 345 | P a g e
  7. 7. Satyendra Singh Tomar, Dr.S.P.Singh / International Journal of Engineering Research and Applications (IJERA) ISSN: 2248-9622 Vol. 3, Issue 2, March -April 2013, pp.340-347450°C arranging and providing all the facilities for the completion of work.Test Result Test Method REFERENCES Obtained [1] CEH, report on polyethylene resins,Specific Gravity 0.7820 IS:1448 P:16 ( 15°C /15°C rts/58 0.1340/) (Accessed in August, 2010).Density @ 0.7815 IS:1448 P:16 [2] W. Kaminsky, M. Predel, A. Sadiki,15°C in kg/cc Polymer Degraation and Satbility,85, 1045KinematicViscosity 1.65 IS:1448 P:25 (2004).@ 40°C in Cst [3] Hegberg., B. A., Brenniman, G. R.,Kinematic Viscosity 0.85 IS:1448 P:25 Hallenbeck, W. H., Mixed plastics@ 100°C in Cst recycling technology. Noyes DataViscosity Index Not IS:1448P:56 Corporation, New Jersey (1992). Available [4] Wallis, M. D., Bhatia, S. K., ThermalConradson 0.01% IS:1448P:122 degradation of high density polyethylene inCarbon Residue a reactive extruder. Polymer DegradationFlash Point by + 2°C IS:1448P:20 and Stability 92, 1721-29 (2007).Abel Method [5] Conesa, J. A., Font, R., Marcilla, A.,Fire Point + 8°C IS:1448P:20 Garcia, A. N., Pyrolysis of polyethylene in aCloud Point - 3°C IS:1448P:10 fluidized bed reactor.Energy and Fuels 8,Pour Point -12°C IS:1448P:10 1238-46 (1994).Gross 10250 IS:1448P:6 [6] Walendziewski, J., Steininger, M., ThermalC.V. in Kcal/Kg and catalytic conversion of wasteSulphur Content 0.016% IS:1448P:33 polyolefins. Catalysis Today, 65, 323-30Cetane Index(CCI) 61 IS:1448 P:9 (2001).Distillation: IS:1448P:18 [7] Beltrame, P. L., Carniti, P., Audisio, G.,Initial BoilingPoint 81°C Bertini, F., Catalytic degradation of10% Recovery 125°C polymers: Part II- Degradation of30% Recovery 186°C polyethylene. Poly Degrade& Stab, 26,50% Recovery 225°C 209-20 (1989).70% Recovery 277°C [8] Bagri, R., Williams, P.T., Catalytic90% Recovery 318°C pyrolysis of polyethylene. Journal of95% Recovery 335°C Analytical and Applied Pyrolysis, 63, 29-41Final Boiling Point 350°C (2002).Residue 1.50 ml [9] Venuto, P. B., Habib, E. T., Fluid CatalyticLoss 0.50% Cracking with Zeolite Catalysts, Marcel Dekker Inc., New York (1979).Table 5: Physical properties of PE thermolytic oil [10] Sharratt, P. N., Lin, Y. H., Garforth, A. A.,sample Dwyer, J., Investigation of the catalytic pyrolysis of high- density polyethylene over a HZSM-5 catalyst in a laboratory3. CONCLUSION fluidized-bed reactor. IECR, 36, 5, 118-124 The liquid yield is highest at 400°C. Highly (1997).volatile products are obtained at low temperature. [11] Lee, K. H., Shin, D. H., CatalyticThe products obtained at 450°C and 500°C,areviscous liquid and wax and the product obtained at degradation of waste polyolefinic polymers550°C is only wax. Liquid yield increases as the using spent FCC catalyst with variousholding time increases from 1 hr to 4 hr at experimental variables. Korean JCE, 20,temperatures from 350°C to 400°C, but as the (1), 89-92 (2003).holding time increases from 4 hr to 6 hr, the liquid [12] Lee, K. H., Jeon, S. G., Kim, K. H., Noh, N. S., Shin, D. H., Park, J., Seo, Y. H., Yee,yield decreases. Reaction time decreases with anincrease in temperature. It has been shown that a J. J., Kim, G. T., Thermal and catalyticsemi-batch thermolysis method can convert waste degradation of waste high-densitypolyethelene to liquid hydrocarbon products with a polyethylene using spent FCC catalyst. Korean JCE, 20, (4), 693-97 (2003).significant yield, which varies with temperature. [13] Tiwari D.C., Ahmad E., Singh KKK ., International Journal of ChemicalACKNOWLEDGEMENT Research, Vol 1, No. 2, 31-36 (2009). The authors gratefully acknowledge [14] Seo, Y. H., Lee, K. H., Shin, D. H.,Director, BIT, Sindri, for his esteemed support in Investigation of catalytic degradation of 346 | P a g e
  8. 8. Satyendra Singh Tomar, Dr.S.P.Singh / International Journal of Engineering Research and Applications (IJERA) ISSN: 2248-9622 Vol. 3, Issue 2, March -April 2013, pp.340-347 high-density polyethylene by hydrocarbon removal by applying various additives. group type analysis. Journal of Analytical Energy Fuels, 24, 1389-1395 (2010). and Applied Pyrolysis, 70, 383-98 (2003).[15] Park, J. W., Kim, J. H., Seo, G., The effect of pore shape on the catalytic performance of zeolites in the liquid-phase degradation of HDPE.Polymer Degradation and Stability, 76, 495-501 (2002).[16] Manos, G., Garforth, A., Dwyer, J., Catalytic degradation of high-density polyethylene over different zeolitic structures. Industrial and Engineering Chemistry Research, 39, 1198-1202 (2000).[17] Hernandez, M. R., Garcia, A. R., Gomez, A., Agullo, J., Marcilla, A., Effect of and absence of HZSM-5.Industrial and Engineering Chemistry Research, 45, 8770- 78 (2006).[18] Garforth, A. A., Lin, Y. H., Sharratt, P. N., Dwyer, J., Production of hydrocarbons by catalytic degradation of high density polyethylene in a laboratory fluidised-bed reactor. Applied Catalysis A: General, 169, 331-342 (1998).[19] Ali, S., Garforth, A. A., Harris, D. H., Rawlence, D.J., Uemichi, Y., Polymer waste recycling over used catalysts.Catalysis Today, 75, 247-255 (2002).[20] Mastral, J. F., Berrueco, C., Gea, M., Ceamanos, J., Catalytic degradation of high density polyethylene over nanocrystalline HZSM-5 zeolite. Polymer Degradation and Stability, 91, 3330-38 (2006).[21] Lin, Y. H., Yang, M. H., Yeh, T. F., Ger, M. D., Catalytic degradation of high density polyethylene over mesoporous and microporous catalysts in a fluidized-bed reactor. Polymer Degradation and Stability, 86,121-128 (2004).[22] Karagoz, S., Yanik, J., Uçar, S., Saglam, M., Song, C., Catalytic and thermal degradation of high-density polyethylene in vacuum gas oil over non-acidic and acidic catalysts.Applied Catalysis A: General, 242, 51-62 (2003).[23] Jan, M. R., Shah, J., Gulab, H., Degradation of waste high-density polyethylene into fuel oil using basic catalyst.Fuel 89, 474-80 (2010).[24] Parikh, P. A., Parekh, D. B., Rotliwala, Y. C., Synergetic pyrolysis of high density polyethylene and Jatropha and Karanj cakes: A thermogravimetric study. Journal of Renewable and Sustainable Energy, 1, 033107 (2009).[25] Kim, J. S., Cho, H., Jung, S. H., Pyrolysis of mixed plastic wastes for the recovery of benzene, toluene and xylene (BTX) aromatics in a fluidized bed and chlorine 347 | P a g e