Althoughtherearevariationsfromdifferentstudies,itisgenerally
shownthatpyrolysisofPEandPPproducedmainlyn-paraffins and1-
olefins inliquidproductsviafreeradicalmechanism(forthermal
pyrolysis) [103] or carboniummechanism(forcatalyticpyrolysis)
[104]. However,thecarbonnumberofhydrocarbonsinliquidproduct
dependsheavilyonreactionparameters,aswellasthetypeofreactor
used. Thepresenceofolefins isgenerallyundesirable,astheycan
easilyrecombinewitheachothertoformlargermolecules,hence
causingdifficulty inindustrialusage.Thisproblemcanbesolvedby
running pyrolysisinhydrogenatmospheretoconvertolefins ton-
paraffins [21,105]. Inhydrogenatmosphere,LDPEpyrolysisproduces
moreparaffin insteadofolefins, withthehelpofsuitablecatalyst [21].
Thedoublebondsintheproductsbecomesaturatedbythehydrogen
present,resultinginhighyieldofparaffin. Inaddition,thehydrogen
atmospherealsopreventscyclo-paraffin intheliquidproducttoform
aromatics.Itisalsoreportedthat extendingreactiontimeresultsin
higher volumeofstraightchainhydrocarbons.Inordertoenhance
the hydroreformingreaction,wherehydrogengasisusedascarrier
gas inpyrolysisreactor,suitablecatalystsareneededtoprovide
reactionsitesfortheunsaturatedhydrocarbons.Theliquidproduct
formed from polymer pyrolysis is suitable to be used as fuel in most
tropicalclimateregions,however,freezingproblemmightbeencoun-
teredincolderregions [106]. Aftersuitableupgrading,pyrolysisliquid
can beblendedwithcommercialgasolineordieselandusedin
combustion engines
Althoughtherearevariationsfromdifferentstudies,itisgenerallyshownthatpyrolysisofPEandPPproducedmainlyn-paraffins and1-olefins inliquidproductsviafreeradicalmechanism(forthermalpyrolysis) [103] or carboniummechanism(forcatalyticpyrolysis)[104]. However,thecarbonnumberofhydrocarbonsinliquidproductdependsheavilyonreactionparameters,aswellasthetypeofreactorused. Thepresenceofolefins isgenerallyundesirable,astheycaneasilyrecombinewitheachothertoformlargermolecules,hencecausingdifficulty inindustrialusage.Thisproblemcanbesolvedbyrunning pyrolysisinhydrogenatmospheretoconvertolefins ton-paraffins [21,105]. Inhydrogenatmosphere,LDPEpyrolysisproducesmoreparaffin insteadofolefins, withthehelpofsuitablecatalyst [21].Thedoublebondsintheproductsbecomesaturatedbythehydrogenpresent,resultinginhighyieldofparaffin. Inaddition,thehydrogenatmospherealsopreventscyclo-paraffin intheliquidproducttoformaromatics.Itisalsoreportedthat extendingreactiontimeresultsinhigher volumeofstraightchainhydrocarbons.Inordertoenhancethe hydroreformingreaction,wherehydrogengasisusedascarriergas inpyrolysisreactor,suitablecatalystsareneededtoprovidereactionsitesfortheunsaturatedhydrocarbons.Theliquidproductformed from polymer pyrolysis is suitable to be used as fuel in mosttropicalclimateregions,however,freezingproblemmightbeencoun-teredincolderregions [106]. Aftersuitableupgrading,pyrolysisliquidcan beblendedwithcommercialgasolineordieselandusedincombustion engines
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