ХИМИЧЕСКИЕ НАУКИ
PYROLYSIS OF LOW DENSITY POLYETHENE (L.D.P.E) AND ANALYSIS OF ITS BY-PRODUCTS IN COMPARISON WITH JP-4 AVIATION FUEL Ihuaenyi S.Ch.1, Fakhrutdinov R.Z.2 Email: [email protected]
1Ihuaenyi Salvation Chijioke - Bachelor student, DEPARTMENT OF CHEMICAL TECHNOLOGY AND ENGINEERING;
2Fakhrutdinov Revo Ziganshinovich - Professor, DEPARTMENT OF CHEMICAL TECHNOLOGY OF OIL AND GAS REFINING, KAZAN NATIONAL RESEARCH AND TECHNOLOGICAL UNIVERSITY,
KAZAN
Abstract: non-biodegradable plastics are the major causes of pollution in the world today, this is a problem that has been frequently recurrent for a very long time. Polyethene is the most common thermoplastic with wide range of application and an average of about 80 million tonnes produced per annum. Its primary use is in packaging (plastic bags, plastic films, geomembranes, containers including bottles) and in Africa it is widely used for packaging drinking water, usually referred to as "sachet water " [1]. This research work focuses on Low Density Polyethene - a grade polymer, its effective management and usefulness when transformed into other products by pyrolysis. In this work, waste polyethene materials were gathered from dumpsites, sterilized and pyrolyzed at different temperatures using a home-made batch reactor and different products were formed at different temperature ranges: 140-190°C, 200-300oC, 300-470oC during the process. The process entails the use of three different samples ofpolyethene of mass 300g, the sample was pyrolyzed and results were recorded and analyzed. The fuel oil produced from the pyrolysis of waste water sachets can therefore be used in place of JP-4, providing the aviation industry with a cheaper fuel oil from a cheaper source (waste LDPE) than crude oil. Keywords: polymer, polyethylene, pyrolysis, fuel, wax.
ПИРОЛИЗ ПОЛИЭТИЛЕНА НИЗКОЙ ПЛОТНОСТИ (ПЭНП) И АНАЛИЗ ПОБОЧНЫХ ПРОДУКТОВ ПО СРАВНЕНИЮ
С АВИАЦИОННЫМ ТОПЛИВОМ JP-4 12 Ихуаенйи С.Ч. , Фахрутдинов Р.З.
1Ихуаенйи Салвейшн Чиджиоке - бакалавр, кафедра химической технологии; 2Фахрутдинов Рево Зиганшинович - профессор, кафедра химической технологии переработки нефти и газа, Казанский национальный исследовательский технологический университет,
г. Казань
Аннотация: бионеразлагаемые пластики являются основной причиной загрязнения в современном мире, и эта проблема часто повторяется в течение очень долгого времени. Полиэтилен является наиболее распространенным термопластом с широким спектром применения и производится в среднем в количестве около 80 миллионов тонн в год. Его основное использование - в качестве упаковки (полиэтиленовые пакеты, пластиковые пленки, геомембраны, контейнеры, включая бутылки). В Африке его широко используют для упаковки питьевой воды, обычно называемой «саше» [1].
Эта научно-исследовательская работа посвящена полиэтилену низкой плотности -качественному полимеру, его эффективному управлению и полезности при превращении в другие продукты путем пиролиза. В этой работе отработанные полиэтиленовые материалы были собраны на свалках, стерилизованы и подвергнуты пиролизу при различных температурах с использованием реактора периодического действия, в ходе процесса были получены различные продукты при различных температурных диапазонах: 140-190 °С, 200-300 °С, 300-470 °С. Процесс предусматривает использование трех разных образцов полиэфира массой 300 г, образец подвергался пиролизу, результаты регистрировались и анализировались. Таким образом, вместо JP-4 можно использовать мазут, полученный в результате пиролиза саше сточных вод, что обеспечивает авиационную промышленность более дешевым мазутом из более дешевого источника (отходы ПЭНП), чем сырая нефть. Ключевые слова: полимер, полиэтилен, пиролиз, мазут, воск.
УДК 66.092.977
INTRODUCTION
The use of polyethene for packaging of goods and products is a trend widely accepted in our world today and this trend bears no end in sight because the distributors of these goods and products find the use of polyethene packaging lighter and cost effective in the overall packaging and distribution of their various outputs. During polyethene packaging, lots of waste polyethene materials are realized and most producers tend to burn them, thereby resulting in the formation of dense fumes which in turn causes air pollution and ozone layer depletion, others retire to the process of burying them in large pits, but for the fact that this plastic is non-biodegradable, they remain underground for years, causing land pollution.
Life would almost be impossible without polyethene because as widely as polyethylene products are used, so also are their spent/used parts/components are found all over the places constituting serious environmental mishap and other related problems, they therefore pose serious environmental problems to inhabitants especially where solid wastes are deposited in towns (urban areas) and villages (rural areas). Urban waste disposal is the responsibility of various municipalities, local government and/or city co-operations [4].
Lots of studies have taken place in the past in order to solve the problem of these waste, The method to be discussed below allows for and easy, cost effective process of converting these waste into useful materials.
POLYETHENE
Polyethene is a polymer made up of the combination of many monomers of ethene (C2H4), so most polyethene have a general formula of (C2H4)n, with "n" being the number of ethene monomer units contained in the overall polymer [2]. Polyethene is an addition polymer that is created by the polymerization of ethylene monomer units. Ethylene can be polymerized by a radical mechanism under very high pressures and temperatures with the addition of an organic peroxide radical initiator [3]. The process requires a highly purified ethylene feed and the operating pressure ranges from 1000 to 3000 atm and a temperature range of 120-3000C.Temperatures exceeding 3000oC cause ethylene to decompose and are not recommended in practice [2]. Therefore, the development of mathematical models to predict the process behaviour is important to ensure a stable operation, associated with an improvement in the properties of the produced polymer.
MATERIALS NEEDED
• Low density polyethene films (gathered from dumpsites around the city)
• Heater
• Batch reactor
• Thermocouple
• Condenser
• Water at 298K for cooling
• Lagging material to prevent heat loss
• Measuring cylinder
• Weighing balance
• Steel spoon for stirring
• Nitrocellulose thinning
METHOD
1. Low density polyethene material waste was gathered from major dumpsites, these materials were screened washed, dried and cut into smaller sizes. Later, they were soaked in Nitrocellulose thinning in order to remove the labels and other ink related mater on them.
2. 300g of polyethene was weighed and passed into the reactor through the hopper, The hopper was then properly covered. Adequate precautions were put in place to make sure there is no leakage before start of experiment. The heater was then switched on and the pyrolysis continued, until the last drop of oil was noticed in the measuring cylinder. A glass condenser was connected tightly to the reactor to cool the condensing vapour from the reactor. Water at 25oC, connected counter currently was used to cool the vapor. No catalyst was used.
3. The volume of fuel oil produced was observed with respect of time and temperature for the sample.
4. The two major products that were formed after the pyrolysis were: wax and fuel oil
5. The products produced during the pyrolysis were analyzed and some physical and chemical properties were obtained.
RESULTS
Table 1. Products obtainedfrom pyrolysis of LDPE
Temperature (oC) Mass of waste polyethene (g) Mas s of fuel oil (g) Mass of wax (g) Mass of gaseous products (g) Mass of carbon residue (g)
140-190 293.16 54.90 228.42 9.84 0.00
200-300 289.65 99.84 165.87 23.04 0.00
300-400oC 300 259.5 0.00 5.79 34.68
It is to be noted that the wax was collected in liquid form and required about 20-30 minutes to solidify at room temperature.
Analysis of the fuel oil showed that it contained several polyaromatic molecules with Acenaphthylene being the most abundant. The fuel did contain water or ash and also had zero Sulphur content.
Further analysis of the fuel oil provided its physical properties as follows:
Table 2. Рhysical properties of fuel oil produced
properties quantity
Density at 15oC 0.77 g/cm3
specific gravity at 15 oC 0.77
Saybolt viscosity at 15oC >5.38 cSt
Flash point <26 oC
Pour point 3 oC
Distillation range 45-360 oC
Heat of combustion 2.91 x107 KJ/mol
Hydrogen content 14.77 %
Carbon content 85.23 %
Properties of the fuel oil was compared with those of other fuels and it was confirmed that it had major similarities with the JP-4 fuel. JP-4 is a widecut (mixture of gasoline and kerosene) fuel oil that is used by the U.S Air force as aircraft fuels. It is also called jet fuel-4. JP-4 is a colorless to straw-colored liquid. It smells like gasoline and /or kerosene. JP-4 is flammable. Refining kerosene, a petroleum oil or shale oil can make JP-4. JP-4 is a blend of chemical made according to standards specified by the U.S. Air force for each fuel. JP-4 is liquids at room temperature, but can also change into vapor [5].
Table 3. Comparison ofproduced fuel oil produced with JP-4 aviation fuel
Properties Fuel oil JP-4
Hydrogen content 14.77 % >13.5 %
Distillation range 45-360 oC 40-270 oC
Physical state liquid liquid
Flammability Flammable at room temperature Flammable at room temperature
colour Light yellow colorless
Density at 15oC 0.77 g/cm3 0.751-0.802 g/cm3
API 55 45-57
CONCLUSION:
The pyrolysis of waste low density polyethene waste to produce fuel oil increases with temperature. On the other hand, it was noticed that as temperature increased, the amount of wax produced decreased. The physical properties of the fuel oil produced compared favorably with that of Aviation fuel JP- 4, which shows that the fuel oil can be used in place of JP- 4, which is more expensive than Kerosene. Petroleum products like kerosene, gasoline, diesel oil etc could be obtained by pyrolyzing at lower temperature since the fuel oil produced contains C3 to C38. The effective management of the polythene waste through conversion into further usable products turns the littered surrounding to an environmentally friendly one by preventing outspread of disease and simultaneously creating employment for both skilled and unskilled labour.
References / Список литературы
1. Ademiluyi T., Akpan C., 2004. Production of fuel oil from pyrolysis of waste polyethylene (pure water sachets).
2. MorrisonRT., BoydR.N., 1973. Organic Chemistry. 3rd Ed. Allyn and Bacon Inc.
3. Perry R.H., Green D., 1987. Perry's Chemical Engineers' Handbook McGraw Hill International Edition.
4. Kiran N., Ekinci E., Snape C.E., 2000. Recycling of plastic waste via pyrolysis. J Resources, Conservation and Recycling.
5. ATSDR's Toxicological profile for Jet Fuels JP - 4 and JP - 7, 1995. US Public Health Service, Atlanta GA, US.