Optimization of Thermo-Catalytic Depolymerization of

Optimization of Thermo-Catalytic Depolymerization of

Plastic Waste to Increase the Derived Fuel Yield

Mohammed Kadhim1, Talha Saleem

2

1Ministry of Education, Baghdad, Iraq.

2Green Crescent Environmental Engineering Consultants Pvt. Ltd. Pakistan.

Email Address: Correspondence should be addressed to Mohammed Kadhim [email protected]

Received: 31 Jan 2021, Revised: 5 Feb 2021, Accepted: 12 Feb 2021, Online: 4 Mar 2021

Abstract

The increase in plastic production leads to serious threats to the environment. Due to its Non-Biodegradable

nature it cannot be easily disposed of. Recently new technologies are being used to treat the waste plastic, one is

pyrolysis. This research involves study of process optimization to produce liquid fuel by the thermo-catalytic

pyrolysis of different plastics waste such as (PP), (PE), (PS) and PET bottles using zeolite and silica alumina as

catalyst in a laboratory batch reactor. The key parameters which were optimized included temperature, residence

time, catalysts to feed ratio and heating rate. Through optimization it was found that maximum oil yield is at

470℃, heating rate of 25.5℃/min, residence time of 69 min and catalyst to feed ratio of 4:1. Under these

conditions 79% of the feed plastic was converted into liquid fuel, which after distillation can be used as petrol or

diesel.

Keywords: Solid waste, Non-biodegradability, Pyrolysis, Optimization.

1. Introduction

In today’s society of modern world, the

plastics contribute to all major activities of

daily life such as: automobile industry,

building materials, electronics and

electricity, packing and so on [1]. The

utilization of plastic has increased

extremely as a result of which the

subjected disposal of plastic waste has

generated severe environmental and social

disagreements [2]. Since years plastics are

used extensively for all types of products

demanded by humans. Although despite of

its evident perfection as material like

endurance, resistance to corrosion, light

weight, formability, economic etc., people

started to concern about its low

degradation rate after its life [3]. Immense

production and utilization of plastic

materials bring about a continuous

increment of disposed plastic and as a

result lack of landfill areas, as plastic need

long time to degrade [4].

This indicates that the portion of waste

plastic that ends up in the landfill is still in

large quantity and it covers a huge area

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[5]. Plastic waste can consume up to

billion years for natural degradation

process [6]. The reason for their slow

degradation are the molecular bonds that

contains carbon, hydrogen and some other

elements like chlorine, nitrogen and few

others which make plastic a durable

material [7]. The continued dumping of

plastic waste into the landfill would surely

lead to severe environmental issues [8].

The climate change related to fossil fuels

because of the ejection of carbon dioxide

is obvious with a portion of 98% of carbon

discharges rising from combustion of

fossil fuels [9]. Furthermore, the

degradation of fossil fuel sources and

energy security are anticipated to become a

leading concern within a few generations

[10]. Although the extensive uses of fossil

fuels include the domestic energy

production and in petroleum,

transportation. Apart from this coal and

gas also have other major uses [11]. In the

year 2015 ,the overall production of plastic

has reached up to 322 million tons which

shows a vivid increase as compared to the

production in the year 2011 which was

reported to be 279 million tons [12]. The

world bank states that the percentage of

plastic waste that accounts for the total

municipal solid waste is about 8-12 %

globally and it is expected to increase up to

9-13 % of MSW by the year 2025 [13].

Thus the most efficient way to reduce

plastic waste is the recycling technique.

The recycling ,regenerating and then

utilization of plastic waste has become an

interesting research at national and

international level [14]. Plastic is being

used in many of the products now a days,

so the degradation of polymeric materials

is also related and is of great interest for

some industries [15].

Table 1 :Different types of plastic production annually in 2012[16]

Plastic

Types Polyethylene Polypropylene

Polyvinyl

chloride

Polyethylene

Terephthalate Polystyrene

Ethylene

Vinyl

Acetate

Production

(in million

tons)[17]

65.41 52.75 37.98 19.8 10.55 2.8

To manage plastic waste, the recycling

technique is advised as an replacement

solution to lessen the dumping of plastic

waste to the landfill [18]. Although the

recycling method has still a lower

percentage. The process of recycling the

plastic waste is shown to be problematic

and it can also use high cost because of the

limitations on water pollution and poor

segregation prior to the recycling method

which is labor demanding [19]. In recent

years, the technique of energy regeneration

from plastic waste has been considered an

inventive solution to positively handle the

plastic waste to accommodate the

increasing demand of energy [20]. It is

possible to obtain beneficial energy from

the plastic waste as they are obtained from

petrochemicals which have high calorific

value [21].

2- Materıals And Methods

2.1 Collection of Plastic Waste

The plastic wastes utilized for the

procedure consist majorly of PE, PP, PS

bottles 25% of each in every reaction


feedstock in the used disposable glasses of

plastic materials forms and also, plates,

packing materials and used bottles. Then

the plastic waste collected was subjected to

preprocessing where is was washed as then

shredded in to small pieces of 1cm by

1cm. Make sure that no impurities like

dust of some other enters the pyrolysis

unit. It was made for increasing the contact

surface area of the plastic materials in the

process of melting.

2.2 Pyrolysis

The process of pyrolysis or the cracking

process contains the polymers chain break

down in the molecules having low

molecular weight that can be used. It can

be made by the utilization of heat at

atmospheric pressure without oxygen that

may be through catalyst or thermally. Here

we used Batch pyrolysis was performed

using a lab setup as shown in the below

process schematic. The setup consisted of

following key components:

A Lindenberg furnace (Model: D-

130 NEYTECH) for heating the feedstock,

A mild steel container for pyrolysis

A condensation assembly

A bottle for oil collection

A pump for water circulation

A vacuum pump for air removal

from the unit of the pyrolysis process.

Figure 1: Schematic Diagram

The batch pyrolysis experiments to

produce oil samples were performed using

the following procedure: The fiber-plastic

feedstock to be used was weighed using

electronic scale (model A&D EK-15KL)

having readability of 0.01 g. The entire

assembly was also weighed to conduct

mass balance to account the weight of any


oil condensed in the transfer line. The

furnace was set at temperature of 500°C.

After the plastic feed is subjected into the

pyrolysis unit the air will be pumped out

of the pyrolyzer to create vacuum in it.

The main purpose of doing is this that

during the process if the oxygen is present

in the unit then there is a chance that

dioxins and furnace will be produced and

increase the toxicity of the plant. The

temperatures could reach steady state

before the start of experiment. The

collection bottle was then weighed, and

liquid collected was measured using

weight difference at the end of experiment.

During the experiment, the inlet for

feedstock was opened and 100 grams of

feedstock containing 25% of each type of

plastic materials along with 2 various

kinds of catalysts was dropped inside the

container/bomb and inlet was sealed back

and adjusted in the muffle furnace. The

vapors formed from pyrolysis of the

feedstock would travel through transfer

line to the condensation system and would

condense in the form of liquid due to the

water bath of collection bottle and cold

water. Pressure during the whole of the

experiment will be monitored. At the

process ending, the collection bottle was

being weighed to measure the yield of the

liquid. The char was measured using the

difference of the weights of the bomb

before and after the process. The liquid

condensed in transfer line that did not

reach collection bottle was measure using

weigh difference of transfer line and was

added to the liquid yield.

The batch experiment is a simple

experiment that requires less time and

operational cost as compared to the paddle

reactor system and can provide oil from

fast pyrolysis required for further testing.

To prove that the batch pyrolysis is indeed

fast pyrolysis, the analysis of transfer of

heat was executed on the batch reactor

system.

2.3. Heat Transfer Analysis

Pyrolysis experiments for this study were

being executed in the batch reactor by

introducing feedstock in a container

(bomb) placed in convective furnace at

500 °C, having the starting temperature of

the particles, to be at ambient temperature.

The materials were kept in the container in

the furnace that was fixed. It is assumed

that temperature of the pyrolysis container

wall is equal to temperature of furnace

after equilibrium was achieved.

Under this situation, the sample was

subjected to heat which was transferred by

the hot walls having temperature to the

surface of the particles through the process

of convection and the heat was being

transferred to the particles through the

process of conduction.

For determination of the system which is

best suitable for the behavior of the system

we have to initiate the research through the

biot number and the thermal thiele

modulus, the first one is connected to the

system of heating of the particles and the

other one is related to the generation of the

Torre faction reaction in the particles.

The Bi and M are defined as:

𝑩𝒊 =𝒉

ℷ/𝒍𝒄…………. (1)

𝑴 =𝑹+

ℷ/(𝑪𝒑∗𝑳𝒄𝟐)……… (2)

Here h is coefficient of transfer of

convective heat; λ is defined as the thermal

conductivity of the particles, Lc is the

characteristic length of the particles, R† is

defined as the rate of reaction of the

pyrolysis in the particles, Cp is the heat

capacity of the particles, and ρ is the

density of the particles. The factors which

are needed for determination of Bi and M

through the equations 1 and 2 seem not to

be easy for determination because the

materials are not properly defined and thus

we may only give an approximation. The


heat transfer coefficient value that is h was

preferred to be 10 W/m2-K and it was

mostly close to the conditions of the flow

in the furnace [89]. The thermal

conductivity value that is λ for thermal

conductivity ranges between 0.15 W/m-K

in case of polyvinyl chloride to 0.38 W/m-

K in case of PE, for the fibers and biomass

the values varies in the range of 0.03 to

0.29 W/m-K [90]. In present research, the

average density was found to be 800

(kg/m3) for the loose fiber/paper material

and 850 (kg/m3) for the plastic [91]. The

value of the heat capacity that was selected

form the literature to produce a suitable

value of 400 (J/Kg-K) for fiber/paper and

~1400 (ranges from 1300-1670) for

plastic. (i) Bi of ~0.05 (ii) M of ~1.4. The

Bi values lie in the range ~0.1 which

indicated that the heat transfer rate through

convection form the walls of the furnace to

the particles was less than that of the rate

into the particles. The value of M indicates

that the rate of reaction was higher than the

transfer of heat in the particles. Therefore,

this research shows that propagation of the

reaction was governed through convection

from the walls of the container to the

particle surface, after that the temperature

of the particles suddenly equilibrates.

Founding that the rate of reaction of the

pyrolysis process was being controlled

through the convective transfer of heat

from the wall to the surface of the particles

and also that the temperature of the

particles was always consistent which

means that the propagation of the reaction

was by the rate of the ramp-up the

temperature of the particles. For

calculation of the temperature of the

particles through the walls of the surface

of the particles, the heat rate equation

dQ(t)/dt, was required to be resolved and

that was equal to the Cellulose pyrolysis in

the temperature range of 25 to 500 ˚C and

in start the reactions is endothermic after

that it becomes exothermic. The enthalpies

of the reactions of the plastic blends in the

similar range of the temperature were

always positive and varied from the range

of 12.55 to 147.86 J/Kg that is lower than

the Cp value. This shows that the

temperature inside the pyrolyzer is almost

the same as that of the walls of muffle

furnace.

2.4 Post Analysis of The Liquid Oil

The fuel obtained in the liquid form

possess most commonly paraffin,

aromatics, olefins and naphthenes. But

because of the economic issues their

composition was not found. Hence we

preferred to calculate the physical

properties such as flash point, specific

gravity and pour point. The specific

gravity of the produced oil was measured

by the use of a specific gravity bottle of 10

ml. The sample of 10 ml was being taken

in the pipette and the bottle that was

preheated was filled with the sample of the

fuel to the top. The finalized weight of the

sample bottle was measured. This provided

with the sample weight which was then

divided by 100 to provide the specific

gravity as well as the sample density. To

find the pour point the sample was being

collected in the test tube and was kept in

ultra-low temperature in the refrigerator.

The refrigerator contains the capacity of

providing temperature of -85 °C. After

drop of every 5 ˚C in the temperature the

sample was being removed out of the

refrigerator and its fluidity was observed.

At a specific temperature the liquid stops

to flow and this temperature was regarded

as the fluid pour point. The samples flash

point was measured by usage of Pensky

Martin apparatus. Almost 30 ml of sample

was collected in the apparatus cup and it

was then cooled through the water bath.

The stirring was provided continuously

throughout the process. After each

temperature decrease of 1˚C the sample

vapors were subjected to the flame. The

point at which there is initiation of fire

with the flash is regarded as the flash

point.


3- Results and Dıscussıons

The different experiments on the process

of pyrolysis were executed through using

the high density polyethylene to be used as

raw materials. Both types that is thermal

and catalytic cracking was conducted. The

plastic materials were cracked thermally at

different ranges of the temperature. The

obtained products consisted of various

compositions and the yield of the products

was varied for various temperature ranges.

In case of cracking by using catalysts the

catalysts which were used included

aluminum silicate, silica alumina, activated

carbon and modernite. The experiments

were executed by use of various catalysts

to feed ratios. All the reactions needed

different conditions of the temperatures

and different ranges of the time. As a

result, the products obtained were varied

according to the respective conditions.

3.1- Thermal Cracking

The cracking of the plastic materials in the

absence of the catalysts produced a fine

concentration of the liquid products but the

issue was that some time was needed for

the product to be settled. The types of

plastics used were the same for all the

reactions i.e. (PE, PS, PP, and PET). Few

process parameters were kept constant

while the reaction to observe different

behaviors of plastic waste. 100g of sample

was used containing 25% of each type of

plastic waste. All others process

parameters like residence time, heating

rate were kept constant results of different

reaction are shown in the below table.

Table 2: Effect of Temperature on the Process

Feed

Quantity

(Grams)

% (PE,PS,PP,PET) Retention Time (Min)

Heating Rate

(ºC)

Temperature

ºC

Liquid

Product

(Ml)

100 25% Each 60 15 400 50

100 25% Each 60 15 450 56

100 25% Each 60 15 500 63

100 25% Each 60 15 550 65

100 25% Each 60 15 600 58


Figure 2: Temperature Vs Product Yield

All other parameters were kept constant accept the residence time.

Table 3: Effect of Residence Time on the process

Feed

Quantity

(Grams)

%(PE,PS,PP,PET) Retention Time (Min)

Heating Rate

(ºC)

Temperature

ºC

Liquid

Product

(Ml)

100 25% each 35 15 500 51

100 25% each 45 15 500 53

100 25% each 55 15 500 54

100 25% each 65 15 500 60

100 25% each 75 15 500 65

45

50

55

60

65

70

350 400 450 500 550 600 650

Pro

du

ct Y

ield

(m

l)

Temperature (°C)

Temperature Vs Product Yield Graph


Figure 3: Effect of Residence Time

Effects of residence time upon the yield were observed by keeping all other parameters

constant.

Table 4: Effect of Heating Rate on the Process

Feed

Quantity

(Grams)

%(PE,PS,PP,PET)

Retention Time (min) Heating Rate

(ºC/min)

Temperature

ºC

Liquid

Product

(ml)

100 25% each 60 10 500 54

100 25% each 60 15 500 56

100 25% each 60 20 500 63

100 25% each 60 25 500 65

100 25% each 60 30 500 67

45

50

55

60

65

70

30 40 50 60 70 80

Pro

du

ct Y

ield

(m

l)

Retention Time (°C)

Retention Time Vs Product Yield Graph


Figure 4: Effect of Heating Rate

Figure 5: Effect of Temperature, Residence Time and Heating Rate on Product Yield

3.2 Catalytıc Cracking

The research includes the decomposition

of waste plastic into the liquid fuel aided

thermally ad by using catalysts like silica

alumina and natural zeolites. The influence

of the temperature and the presence of

catalysts on the reaction rate, distribution

of the product and quality have been

analyzed.

50

52

54

56

58

60

62

64

66

68

5 10 15 20 25 30 35

Pro

du

ct Y

ield

(m

l)

Heating Rate (°C/ min)

Heating Rate Vs Product Yield Graph


A. Effect of Temperature

While catalytic cracking the temperature

required to obtain the good amount of

yield will be less than that of thermal

cracking so a lesser temperature ranges

will be selected.

Table 5: Effect of Temperature on the process in presence of Catalyst

Feed

Quantity

(grams)

Catalyst to Feed

Ratio

Retention

Time(min)

Heating

Rate

(ºC/min)

Temperature

ºC

Liquid Product

(ml)

100(25%each) 4:1 60 15 350 44

100(25%each) 4:1 60 15 400 50

100(25%each) 4:1 60 15 450 67

100(25%each) 4:1 60 15 500 68

100(25%each) 4:1 60 15 550 55

Figure 6: Effect of Temperature in presence of Catalyst

B. Effects of Catalyst to Feed Ratio

Two catalysts were used i.e. zeolite and silica alumina both of them were used in equal

concentrations a range of catalysts to feed ratio was selected through literature and the effects

of the catalysts were observed

40

45

50

55

60

65

70

75

300 350 400 450 500 550 600

Pro

du

ct Y

ield

(m

l)

Temperature (°C)

Temperature Vs Product Yield Graph (with catalyst)


Table 6: Effect of Catalyst to Feed Ratio on the process

Feed

quantity

(grams)

Catalyst to feed

ratio

Retention

time(min)

Heating

rate

(ºC/min)

Temperature

ºC

Liquid product

(ml)

100(25%each) 2:1 60 15 350 48

100(25%each) 3:1 60 15 400 50

100(25%each) 4:1 60 15 450 68

100(25%each) 5:1 60 15 500 57

100(25%each) 6:1 60 15 550 54

Figure 7: Catalyst to Feed Ratio


C. Effects of Retention Time on Yield

Table 7: Effect of retention Time on the process

Feed

quantity

(grams)

Catalyst to feed

ratio

Retention

time(min)

Heating

rate

(ºC/min)

Temperature

ºC

Liquid product

(ml)

100(25%each) 4:1 45 15 350 44

100(25%each) 4:1 50 15 400 50

100(25%each) 4:1 55 15 450 67

100(25%each) 4:1 60 15 500 68

100(25%each) 4:1 65 15 550 71

Figure 8: Effect of Residence Time in presence of Catalyst


D. Effects of Heating Rate on Yield

Table 8: Effect of Heating Rate on the process in presence of Catalyst

Feed quantity

(grams)

Catalyst to

feed ratio

Retention

time(min)

Heating

rate

(ºC/min)

Temperature

ºC

Liquid product

(ml)

100(25%each) 4:1 60 10 350 44

100(25%each) 4:1 60 15 400 50

100(25%each) 4:1 60 20 450 67

100(25%each) 4:1 60 25 500 68

100(25%each) 4:1 60 30 550 68

Figure 9: Effect of Heating Rate in presence of Catalyst

50

52

54

56

58

60

62

64

66

68

5 10 15 20 25 30 35

Pro

du

ct Y

ield

(m

l)

Heating Rate (°C/ min)

Heating Rate Vs Product Yield Graph


Figure 10: Effect of Heating Rate, Temperature, Retention Time and Catalyst to Feed Ratio

on product yield


E. Effects of Different Types of Plastics on Yield

Table 9: Effects of Different Types of Plastics on Yield

Feedstock

Types

Quantity

(g)

Ratio (%)

Retention

Time

(min)

Temperature

(C)

Heating

Rate (C/

min)

PS 100 100 75 450 10

PE 100 100 75 450 10

PP 100 100 75 450 10

PET 100 100 75 450 10

PS/PE 100 50/50 75 450 10

PS/PP 100 50/50 75 450 10

PS/PET 100 50/50 75 450 10

PE/PP 100 50/50 75 450 10

PE/PET 100 50/50 75 450 10

PP/PET 100 50/50 75 450 10

PS/PE/PP 100 50/25/25 75 450 10

PS/PP/PET 100 50/25/25 75 450 10

PS/PE/PET 100 50/25/25 75 450 10

PE/PP/PET 100 50/25/25 75 450 10

PS/PE/PP/PET 100 25/25/25/25 75 450 10


Figure 11: Effects of different types of plastic on product yield

a. Optimization of Process

Parameters

In the recent research various factors that

affect the plastic waste degradation in a

batch reactor are identified and explained

in the chapter of methodology. In this

portion, with the aid of an optimization

software i.e., Design Expert the optimized

values of different process parameters like

that of catalysts to feed ratio, retention

time, heating rate, temperature could be

obtained. A selected rage from literature

was selected for different parameters of the

process and the range was substituted in

the software, a series of reactions was

obtained.

82

[VALUE] 70

65 70

63 58

65

44

52

60 59

65

57

73

18

27 30

35 30

37 42

35

56

48

40 41

35

43

27

0

10

20

30

40

50

60

70

80

90

PS

PE

PP

PET

PS/

PE

PS/

PP

PS/

PET

PE/

PP

PE/

PET

PP

/PET

PS/

PE/

PP

PS/

PP

/PET

PS/

PE/

PET

PE/

PP

/PET

PS/

PE/

PP

/PET

Pro

duct

Yei

ld (

%)

Different combinations of plastic

Effects of different types of plastic on product yield OIL


Table 10: Optimization of Process

Figure 12: Oil Production Optimization by Design Expert


Figure 13: Oil Production Optimization by Design Expert

Figure 14: Oil Production Optimized Values by Design Expert


Table 11: Response Surface Quadratic Model by Design Expert

ANOVA for Response Surface Quadratic Model

Analysis of variance table [Partial sum of squares - Type III]

Sum of Mean F p-value

Source Squares df Square Value Prob > F

Model 555.69 9 61.74 1.51 0.3008 not

significant

A-Temperature 210.13 1 210.13 5.13 0.0578

B-Heating Rate 15.13 1 15.13 0.37 0.5625

C-Retention Time 12.50 1 12.50 0.31 0.5977

AB 56.25 1 56.25 1.37 0.2795

AC 4.00 1 4.00 0.098 0.7637

BC 100.00 1 100.00 2.44 0.1620

A2 43.79 1 43.79 1.07 0.3354

B2 31.27 1 31.27 0.76 0.4111

C2 66.53 1 66.53 1.63 0.2430

Residual 286.55 7 40.94

Lack of Fit 59.75 3 19.92 0.35 0.7917 not

significant

Pure Error 226.80 4 56.70

Cor Total 842.24 16


Table 12: Final Equation in Terms of Actual Factors by Design Expert

Final Equation in Terms of Actual Factors

Oil Production =

+4.85000

+0.19425 * Temperature

-2.27250 * Heating Rate

+1.27000 * Retention Time

+3.75000E-003 * Temperature * Heating Rate

+6.66667E-004 * Temperature * Retention Time

+0.033333 * Heating Rate * Retention Time

-3.22500E-004 * Temperature2

Optimization studies shows that

Table 13: Optimized Results from Design Expert

Number Temperature Heating Rate Retention Time Oil Production Desirability

1 470.88 25.79 69.77 78.1079 1.000

The results from optimization study shows

that for a plastic feed containing mixed

plastic in an equal ratio the maximum oil

production can be achieved at the

temperature of 470.88 ℃ at the rate of

heating of 25.79℃/min and a retention

time of 69.77. The crude oil thus produced

can be further subjected to the distillation

plant and pure products like that of petrol

and diesel can be produced.

b. Post Analysis of Oil

Few post analysis tests were conducted on

the pyrolysis oil and the results from the

analysis (table given below) clearly shows

that the oil produced from the plastic has

greater energy and combustibility. The

results from different experiments can be

shown below.


Table 14: Post Test Analysis

Physical

Properties Units

(Experimental values for

plastic waste)

Commercial standard

values of diesel

Method

used

Viscosity (mm2/sec) 1.5 1.3

ASTM

D445

Pour point

℃

-55 -40 ASTM D97

Flash point ℃ 36.5 55 ASTM D93

Fire point ℃ 37.5 56.5 ASTM D92

Density 15℃(g/ml) 0.9406 0.8426 ASTM

D4052

Specific

gravity

@15.6

g/cm3

0.85 0.96 ASTM

D792

4- Conclusions

The plastic waste was passes through

different conditions of the reactions to start

form cracking thermally towards the

cracking by using catalysts by various

catalysts to feel ratios, different

Temperatures, different retention time as

well as different heating rates. The

products gained in each case were varied

from the others regarding the liquid

product yield or in the physical properties.

Initially various kinds of wastes plastics

were subjected in the reaction and their

effect were observed it was found that

the PS produces the maximum yield of

oil.

For cracking process thermally, the

process produced fine concentration of

the products. But the major issue is that

some time is required to solidify the

products completely. It might be as it

was exposed to the high temperatures. It

was analyzed in this situation that for

the initial some minutes, fine product

quality was produced but instantly after

some time impure products were

produced. This drive towards the

product solidifying.

The optimization study shows that at the

time when the plastic materials were

cracked by using catalysts using zeolite

and silica alumina and it produced good

quality and quantity of the liquid fuels.

The greatest yield was produced when

the feed to catalyst ratio was about 4:1.

During this situation it needed a

temperature range of about 470˚C the

residence time of about 69.7 minutes

and rate of heating of 25 ˚C /minutes.

The products obtained in the liquid form

were very combustible in nature and the

specific gravity varies in the diesel oil

and gasoline range. So, it may be

inferred to be in the range of gasoline.

The gasoline flash point is found to be

7°C and of the diesel oil is in the range

of 60 to 80°C. The samples flash point

is in the range of 30 to 32. So the fuels

might lie in the diesel oil and gasoline

range.


5. References

1. Pinto, F., et al., Pyrolysis of plastic wastes.

1. Effect of plastic waste composition on

product yield. Journal of Analytical and

Applied Pyrolysis, 1999. 51(1-2): p. 39-55.

2. Buekens, A. and H. Huang, Catalytic

plastics cracking for recovery of gasoline-

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