Kinetic Modeling of Hydrocracking of Low-Density Polyethylene in a Batch Reactor

AbstractUtilization of oils/waxes obtained from thermal cracking of individual LDPE (low density polyethylene), HDPE (high density polyethylene), LLDPE (linear low density polyethylene), PP (polypropylene), or cracking of mixed polymers PP/LDPE (1: 1 mass ratio), HDPE/LDPE/PP (1: 1: 1 mass ratio), HDPE/LDPE/LLDPE/PP (1: 1: 1: 1 mass ratio) for the production of automotive gasolines and diesel fuels is overviewed. Thermal cracking was carried out in a batch reactor at 450°C in the presence of nitrogen. The principal process products, gaseous and liquid hydrocarbon fractions, are similar to the refinery cracking products. Liquid cracking products are unstable due to the olefins content and their chemical composition and their properties strongly depend on the feed composition. Naphtha and diesel fractions were hydrogenated over a Pd/C catalyst. Bromine numbers of hydrogenated fractions decreased to values from 0.02 g to 6.9 g of Br2 per 100 g of the sample. Research octane numbers (RON) before the hydrogenation of naphtha fractions were in the range from 80.5 to 93.4. After the hydrogenation of naphtha fractions, RON decreased to values from 61.0 to 93.6. Diesel indexes (DI) for diesel fractions were in the range from 73.7 to 75.6. After the hydrogenation of diesel fractions, DI increased up to 104.9.

Download Full-text

Catalytic Cracking of LLDPE over MCM-48

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.124-126.1757 ◽

2007 ◽

Vol 124-126 ◽

pp. 1757-1760 ◽

Cited By ~ 1

Author(s):

Jong Ki Jeon ◽

Hyun Ju Park ◽

Jin Heong Yim ◽

Ji Man Kim ◽

Jin Ho Jung ◽

...

Keyword(s):

Activation Energy ◽

Catalytic Cracking ◽

Oil And Gas ◽

Degradation Products ◽

Batch Reactor ◽

Low Density Polyethylene ◽

Low Density ◽

Linear Low Density Polyethylene ◽

Thermogravimetric Analyzer ◽

Catalytic Stability

Applicability of Al-MCM-48 as a catalyst for the linear low density polyethylene (LLDPE) degradation was investigated using a thermogravimetric analyzer as well as a batch reactor. The degradation products were analyzed by GC/MS, GC-TCD and GC-FID. The activation energy of LLDPE degradation was lowered by the addition of Al-MCM-48. The oil and gas yields were higher over Al-MCM-48 than those over Si-MCM-48. Al-MCM-48 generated mainly C7-C10 hydrocarbons, while Si-MCM-48 exhibited the relatively broader distribution of the oil products (C8-C14). Al-MCM-48 showed high catalytic stability for the LLDPE degradation.

Download Full-text

Catalytic Pyrolysis of Low Density Polyethylene Using Cetyltrimethyl Ammonium Encapsulated Monovacant Keggin UnitsC19H42N4H3(PW11O39)and ZSM-5

Journal of Chemistry ◽

10.1155/2016/2857162 ◽

2016 ◽

Vol 2016 ◽

pp. 1-5 ◽

Cited By ~ 3

Author(s):

Madeeha Batool ◽

Asma Tufail Shah ◽

Muhammad Imran Din ◽

Baoshan Li

Keyword(s):

High Temperature ◽

Thermal Degradation ◽

Catalytic Cracking ◽

Catalytic Pyrolysis ◽

Batch Reactor ◽

Low Density Polyethylene ◽

Low Density ◽

Hydrophobic Nature ◽

Cetyltrimethyl Ammonium

The effect of the catalysts on the pyrolysis of commercial low density polyethylene (LDPE) has been studied in a batch reactor. The thermal catalytic cracking of the LDPE has been done using cetyltrimethyl ammonium encapsulated monovacant keggin units (C19H42N)4H3(PW11O39), labeled as CTA-POM and compared with the ZSM-5 catalyst. GC-MS results showed that catalytic cracking of LDPE beads generated oilier fraction over CTA-POM as compared to ZSM-5. Thus, the use of CTA-POM is more significant because it yields more useful fraction. It was also found that the temperature required for the thermal degradation of LDPE was lower when CTA-POM was used as a catalyst while high temperature was required for degradation over ZSM-5 catalyst. Better activity of CTA-POM was due to hydrophobic nature of CTA moiety which helps in catalyst mobility and increases its interaction with hydrocarbons.

Download Full-text

Experimental Study of Thermal and Catalytic Pyrolysis of Plastic Waste Components

10.20944/preprints201810.0223.v1 ◽

2018 ◽

Author(s):

Azubuike Francis Anene ◽

Siw Bodil Fredriksen ◽

Kai Arne Sætre ◽

Lars -Andre Tokheim

Keyword(s):

High Density Polyethylene ◽

Catalytic Pyrolysis ◽

Batch Reactor ◽

Decomposition Temperature ◽

Nitrogen Atmosphere ◽

Low Density Polyethylene ◽

Low Density ◽

Waste Plastics ◽

Pp Blends ◽

Hydrocarbon Distribution

Thermal and catalytic pyrolysis of virgin low-density polyethylene (LDPE), high-density polyethylene (HDPE), polypropylene (PP) and mixtures of LDPE/PP were carried out in a 200 ml laboratory scale batch reactor at 460 °C in a nitrogen atmosphere. Thermogravimetric analysis (TGA) was carried out to study the thermal and catalytic degradation of the polymers at a heating rate of 10 °C/min. The amount of PP was varied in the LDPE/PP mixture to explore its effect on the reaction. In thermal degradation (TGA) of LDPE/PP blends, a lower decomposition temperature was observed for LDPE/PP mixtures compared to pure LDPE, indicating interaction between the two polymer types. In the presence of a catalyst (CAT-2), the degradation temperatures for the pure polymers were reduced. The TGA results were validated in a batch reactor using PP and LDPE respectively. Thermal cracking results showed that the oil product contains a significant amount of gasoline (C7 − C12) and diesel (C13 − C20) hydrocarbon fractions. The catalyst enhanced cracking at lower temperatures and narrowed the hydrocarbon distribution in the oil towards the gasoline range fraction (C7 – C12). The result suggests that the oil produced from catalytic pyrolysis of waste plastics has a potential as an alternative fuel.

Download Full-text