Thermocatalytic Conversion of Plastics into Liquid Fuels

Version	Summary	Created by	Modification	Content Size	Created at	Operation
1		Olga E. Lebedeva	--	2327	2022-06-07 13:33:01	\|
2	format change	Peter Tang	-34 word(s)	2293	2022-06-08 03:44:25	\|

This entry is adapted from the peer-reviewed paper 10.3390/polym14102115

The problem of recycling polymer waste remains the main one in the context of the growth in the use of plastics. Given the non-renewability of fossil fuels, the task of processing plastic waste into liquid fuels seems to be a promising one. Thermocatalytic conversion is one of the methods that allows obtaining liquid products of the required hydrocarbon range. Clays and clay minerals can be distinguished among possible environmental-friendly, cheap and common catalysts.

secondary raw materials plastics fuel catalysts clays clay minerals thermocatalytic conversion

1. Introduction

The last few centuries have been marked by the rapid development of mankind. The obvious benefits that it brought were accompanied by new, serious anthropogenic challenges. One of them was the emergence in the 1950s of new synthetic materials—plastics. The main ingredient of plastic are polymers, such as polyolefins (with commercially dominant polyethylene and polypropylene) possessing the general formula (CH₂CHR)_n where R is an alkyl group, polystyrene ((C₆H₅CH = CH₂)_n), polyvinyl chloride ((C₂H₃Cl)_n), etc.

One of the promising solutions is the conversion of plastic waste into liquid fuels. With a catalyst sufficiently selective to produce a mixture of hydrocarbons with an expected carbon number range, it would be possible to obtain liquid products with a composition similar to that of fuels such as gasoline and diesel. Since the production of various catalysts is often accompanied by environmental pollution, a complex preparation process, and, as a result, a high price of the final product, the catalysts must also comply with the principles of green chemistry and have a low cost.

2. Nature of Catalytic Activity of Clays

Clays belong to solid acids. They have both Lewis and Brønsted acid sites (Figure 1) ^[1].

Figure 1. Acidic sites of clays.

The acidic sites are comparatively strong (H₀ typically quoted in the range from −5.6 to −8.2), though not as strong as the zeolite ones ^[1]. All the clays being aluminosilicates, the nature of the active sites is essentially the same for all types of clays. It is porosity that defines the specific features of different clays. Microporosity depends on the crystallographic structure of the material.

Original clays in cationic forms usually contain an insufficient number of acidic sites since the sites involve protons (Figure 1). Only cationic deficient samples of clays demonstrate catalytic activity in the reactions of the acid-base type. Generally, acidic activation is necessary for obtaining catalytically active clays. The conditions of acidic treatment are often crucial for the efficiency of the clay catalysts.

3. Kaolin Group Catalytic Activity

The kaolin group is represented by layered phyllosilicate minerals with the chemical composition Al₂Si₂O₅(OH)₄. The layers of these clay minerals consist of corner-sharing tetrahedra and edge-sharing octahedra. Tetrahedra are formed by silicon atoms, and octahedrons are constructed from aluminum atoms. The way the layers are stacked and the nature of the material between the layers distinguishes the individual minerals (kaolinite, dickite, halloysite, and nacrite, sometimes also serpentine subgroup) in the group ^[2]. Rocks rich in kaolinite are thus called kaolin.

Kaolin-based catalysts are the most commonly mentioned among the articles on clay catalysts for the conversion of plastics into liquid fuels due to the abundant availability of natural kaolin. All results from work on kaolin clay catalysts are presented in Table 1.

Table 1. Publications on the conversion of different plastics over clay minerals from kaolin group catalysts.

Catalyst	Plastic	Temperature, °C	Highest Liquid Yield, wt%	Specific Results	Reference
Kaolinite-containing natural clay	HDPE	478	16	Catalyst produced more alkanes than olefins in both gaseous and liquid oil products.	^[3]
Kaolin and its modifications With CH₃COOH, HCl, H₃PO₄, HNO₃, and NaOH	HDPE	450	78.7	The liquid fuel consisted of petroleum products range hydrocarbons (C₁₀–C₂₅).	^[4]
Kaolin	LDPE	450	79.5	The oil consists of paraffins and olefins with a predominance of C₁₀–C₁₆ components.	^[5]
Kaolin	LDPE	600	about 75	The first addition of kaolin gives aliphatic compounds and C₆–C₂₀ aromatics (90–95%).	^[6]
75% kaolinite with 25% bentonite	LDPE	580	74.45	High yield of paraffins (70.62%). The percentage of aromatics was 5.27%.	^[7]
China clay (kaolinite)	LDPE	300	84	Components with a boiling point of 125–180°C were identified as alkanes, alkenes, and aromatics.	^[8]
Kaolin	LDPE	450	99.82	The highest percentage component is heptane.	^[9]
Al-substituted Keggin tungstoborate/kaolin composite	LDPE	295	84	During the catalytic cracking 70 mol.% of gasoline range hydrocarbons were produced.	^[10]
tungstophosphoric acid/kaolin composite	LDPE	335	81	A high content of benzene-like hydrocarbons (C₁₁–C₁₄).	^[11]
Ahoko kaolin	PP	450	79.85	Liquid products with properties comparable to conventional fuels (gasoline and diesel).	^[12]
Hydrochloric acid/kaolin composite	PP	470	71.9	The condensable hydrocarbons contain dominantly alkanes and alkenes in the range C₆–C₁₂.	^[13]
Commercial-grade kaolin clay	PP	450	89.5	Contains olefins, aliphatic, and aromatic hydrocarbons in the oil comparable with liquid fossil fuels.	^[14]
Commercial-grade kaolin clay and kaolin treated with sulfuric acid	PP	500	92 (acid-treated), 87.5 (neat kaolin)	The oil from the neat kaolin—C₁₀–C₁₈ products, from the acid-treated kaolin—mainly C₉–C₁₃.	^[15]
Kaolin	PP	500	87.5	Fuel properties are identical to the different petroleum fuels.	^[16]
Neat kaolin and kaolin treated with hydrochloric acid	PP	400–500	71.9	The highest yield of liquid hydrocarbons was achieved with kaolin clay treated with 3M HCl.	^[17]
Kaolin	PP/vaseline (4.0 wt%)	520	52.5	The gasoline—32.77%, diesel—13.59%, residue—6.14%	^[18]
CuO/kaolin and neat kaolin	PS	450	96.37 (neat kaolin), 92.48 (CuO/kaolin)	The oil contained aromatic hydrocarbons, but from CuO/kaolin—85% C₁₀H₈ and ~13% C₈H₈.	^[19]
Zeolite-Y + metakaolin + aluminum hydroxide + sodium silicate all synthesized from kaolin	HDPE + LDPE + PP + PS + PET	350	46.7	Catalyzed fuel samples consist of 93% gasoline and 7% diesel fraction.	^[20]
Kaolin	Virgin HDPE, HDPE waste and mixed plastic waste	425	79	The catalyst was the most selective in producing diesel, which yielded 63%.	^[21]
Halloysite treated with hydrochloric acid	PS	450	90.2	Aromatic compounds of more than 99%. The main product is styrene (58.82%).	^[22]

4. Smectite Group Catalytic Activity

Members of the smectite group include the dioctahedral minerals (montmorillonite, beidellite, and nontronite) and the trioctahedral minerals (hectorite, saponite, and sauconite). The basic structural unit of these clay minerals is a layer consisting of two inward-pointing tetrahedral sheets with a central alumina octahedral sheet ^[23]. The clay consisting mostly of montmorillonite is called bentonite, but in commerce, this term can be used in a more general way to refer to any swelling clay composed mostly of minerals from the smectite group.

The bentonite- and pure montmorillonite-based catalysts are the most commonly occurred besides smectite catalysts for plastic transformation. There are a few articles devoted to the use of saponite and beidellite. All results from the work on smectite clay catalysts are presented in Table 2.

Table 2. Publications on the conversion of different plastics over clay minerals from smectite group catalysts.

Catalyst	Plastic	Temperature, °C	Highest Liquid Yield, wt%	Specific Results	Reference
Bentonite (50 wt%)/spent fluid catalytic cracking catalyst (FCC)	HDPE	500	100	High yields of gasoline C₅–C₁₁ (50 wt%) The yield of C₁₂–C₂₀ hydrocarbons—8–10 wt%.	^[24]
Pillared bentonite (PILC) intercalated with Fe or Al	HDPE and heavy gas oil (HGO)	500	>80	The oil from the Fe-PILC-Fe-300 catalyst was more similar to the standard diesel.	^[25]
Bentonite (Gachi clay)	LDPE	300	77	Olefin and paraffin hydrocarbons.	^[26]
South Asian clay classified as bentonite andmontmorillonite impregnated with nickel NPs	LDPE and post-consumer polybags	350	79.23 (LDPE), 76.01 (poly-bags)	The final products are in the range of gasoline, kerosene, and diesel.	^[27]
Bentonite thin layer loaded with MnO₂ nanoparticles (NPs)	PP	750	Parameters were designed to get off the liquid	The complete decomposition of plastics with the formation of gases (methane and hydrogen) and coke.	^[28]
Bentonite treated with 0.5M hydrochloric acid	PS	400	88.78	The obtained liquid contains styrene. Toluene and benzene were the major components.	^[29]
Acid-washed bentonite clay (AWBC), Zn/AWBC, Ni/AWBC, Co/AWBC, Fe/AWBC, Mn/AWBC	PP, HDPE	300 for PP and 350 for HDPE	AWBC (PP 68.77, HDPE 70.19), Ni/AWBC (PP 92.76, HDPE 62.07), Co/AWBC (PP 82.8, HDPE 69.31), Fe/AWBC (PP 82.78, HDPE 71.34), Mn/AWBC (PP 80.4, HDPE 81.07), Zn/AWBC (PP 82.50, HDPE 91)	Co/AWBC/PP (mainly olefins and naphthenes) and Zn/AWBC/HDPE (mainly paraffins and olefins) were the most effective.	^[30]
H₂SO₄-activated bentonite (synthesized)	PP + HDPE	328	79	The hydrocarbon oil.	^[31]
A mixture of nature bentonite and zeolite (70:30)	PP, PET	400	78.42 (PP), 72.38 (PP + PET)	The number of C₃–C₁₀ compounds increased.	^[32]
Pelletized bentonite	PS, PP, LDPE, HDPE	500	88.5 (PS), 90.5 (PP), 87.6 (LDPE), 88.9 (HDPE)	PS—95% aromatic hydrocarbons; PP, LDPE, and HDPE—aliphatic hydrocarbons; LDPE, and HDPE—diesel fuel (96% similarity); PS—gasohol 91.	^[33]
Calcium bentonite	PP, LDPE, HDPE, PP + LDPE + HDPE	500	88.5 (PP), 82 (LDPE), 82.5 (HDPE) 81 (PP + LDPE + HDPE)	The oil contained only a mixture of hydrocarbons and has matching fuel properties as that of fossil fuel. Mixed plastics—C₁₀-C₂₈.	^[34]
Pillared bentonite (Al-PILC, Fe-PILC, Ti-PILC, Zr-PILC)	HDPE + PS + PP + PET	300–500	68.2 (Al-PILC), 79.3 (Fe-PILC), 62.8 (Ti-PILC), 62.1 (Zr-PILC)	80.5% diesel fraction was observed in presence of Fe-PILC.	^[1]
Fe/Al pillared montmorillonite mixed with an acid Commercial bentonite as a binder	HDPE	600	About 40	The catalyst gave high yields of waxes, particularly rich in diesel hydrocarbon range (C₁₁–C₂₁).	^[35]
commercial acid-restructured montmorillonite and Al- and Fe/Al-pillared derivative	MDPE	300	About 70	The clay-based catalysts gave higher yields of liquid products in the C₁₅–C₂₀ range. Clay catalysts produce liquid hydrocarbons in the gasoline and diesel range.	^[36]
Al₂O₃-pillared montmorillonite (calcium rich)	LDPE	430	70.2	Hydrocarbons from C₅ to C₁₃.	^[37]
Montmorillonite (Zenith-N) and a pillared derivative	LDPE	427	68 (montmorillonite), 75 (pillared derivative)	Clays showed enhanced liquid formation due to their mild acidity.	^[38]
Al-pillared montmorillonite (Al-PILC), and regenerated samples	LDPE	360	72 (Al-PILC), 68 (regenerated sample)	These products were in the boiling point range of motor engine fuels.	^[39]
Montmorillonite (Zenith-N) and a pillared derivative	LDPE	360	75 (montmorillonite), 76 (pillared derivative)	These products were in the boiling point range of gasoline.	^[40]
Ionically bonding macrocyclic Zr-Zr complex to montmorillonite	PP	300–400	-	A low molecular weight waxy product with paraffin wax characteristics was obtained.	^[41]
Untreated and Al-pillared montmorillonite clay	PS	400	83.2 (untreated clay), 81.6 (Al-pillared clay)	Styrene was the major product, and ethylbenzene was the second most abundant one in the liquid product.	^[42]
Four different types of montmorillonites: K5, K10, K20, K30	LDPE, PP, and the municipal waste plastics	begins at 250 for mK5 (LDPE), 210–435 for mK20 (PP)	Data not presented	The catalytic degradation products contain a relatively narrow distribution of light hydrocarbons.	^[43]
Organically modified montmorillonite/Co₃O₄	PP + HDPE + PS	700	59.6	The catalyst promoted the degradation of mixed plastics into light hydrocarbons and aromatics.	^[44]
cloisite 15 A as a natural montmorillonite modified with a quaternary ammonium salt	Industrial grade of HDPE, which was a copolymer with 1-hexene (1.5 wt%) as comonomer	473.7	Data not presented	It was found that the nano clay reduces the temperature at a maximum degradation rate.	^[45]
Commercial acid-restructured saponite and Al- and Fe/Al-pillared derivatives	MDPE	300	About 70	The clay-based catalysts gave higher yields of liquid products in the C₁₅–C₂₀ range. Clay catalysts produce liquid hydrocarbons in the gasoline and diesel range.	^[36]
Saponite, with a small number of impurities, mainly sepiolite and a pillared derivative	LDPE	427	83 (saponite), 82 (coked pillared derivative)	Clays showed enhanced liquid formation due to their mild acidity.	^[38]
Al-pillared saponite and regenerated samples	LDPE	360	72 (pillared saponite), 67 (regenerated sample)	These products were in the boiling point range of motor engine fuels.	^[39]
Saponite and a pillared derivative	LDPE	360	68 (saponite), 72 (pillared derivative)	These products were in the boiling point range of gasoline.	^[40]
Commercial acid-restructured beidellite and Al- and Fe/Al-pillared derivatives	MDPE	300	About 70	The clay-based catalysts gave higher yields of liquid products in the C₁₅–C₂₀ range. The catalysts produce liquid hydrocarbons in the gasoline and diesel range.	^[36]

5. Other Clay Minerals’ Catalytic Activity

The variety of clay minerals is not limited to the above-mentioned two groups. Only a few examples of studying the catalytic activity of other clay minerals (sepiolite, vermiculite, talc, and pyrophyllite) in relation to plastics were found (Table 3).

Table 3. Publications on the conversion of different plastics over sepiolite, talc, pyrophyllite, and vermiculite catalysts.

Catalyst	Plastic	Temperature, °C	Highest Liquid Yield, wt%	Specific Results	Reference
Commercial sepiolite	PE, PP, PS, EVA	432.65 (PE), 401.65 (PP), 449.75 (PS), 459.85 (EVA)	Data not presented	Clay reduces the decomposition temperatures of PE and PP. However, steric effects associated with the PS and EVA substituents nullify this catalytic behavior.	^[46]
Tetraethyl silicate modified vermiculite, Co, and Ni intercalated vermiculite	PP + PE	300-480	80.6 (organic vermiculite), 73.2 (Co/verm), 70.7 (Ni/verm), 73.9 (Co/Ni/verm)	The obtained liquid is mainly composed of C₉–C₁₂ and C₁₃–C₂₀.	^[47]
Talc (French chalk)	LDPE	300	91	Components with a boiling point of 125–180°C were identified as alkanes, alkenes, and aromatics.	^[8]
Talc (plastic filler)	PP	620	About 23	The liquid product contained a higher aromatic content (57.9%) and a lower n-alkene content (5.8%).	^[48]
Pyrophyllite treated with hydrochloric acid	PS	450	88.3	The catalysts showed selectivity to aromatics over 99%. Styrene (63.40%) is the major product, and ethylbenzene is the second-most abundant one (6.93%).	^[22]

6. Catalytic Activity of Mixed Natural Clays

Some works were focused on uncharacterized mixed clays from different fields (Table 4).

Table 4. Publications on the conversion of different plastics over clays from different fields.

Catalyst	Plastic	Temperature, °C	Highest Liquid Yield, wt%	Specific Results	Reference
Acid-activated fire clay (Pradeep Enterprises, Ajmeri Gate, Delhi)	HDPE	450	41.4	The identified compounds were mainly paraffins and olefins with a carbon number range of C₆–C₁₈.	^[49]
Indian Fuller’s earth (Multan clay)	LDPE	300	58.33	The obtained liquid contained olefin, paraffin, and aromatic hydrocarbons. Light naphtha—15%, heavy naphtha—35%, middle distillate—60%.	^[50]
Fuller’s earth	LDPE	300	91	Components with a boiling point of 125-180°C were identified as alkanes, alkenes, and aromatics.	^[8]
Natural clay mineral (Indonesia) with LaFeO₃ NPs	PP	460–480	88.8 (5th cycle)	The liquid fraction: alkanes (44.70%), alkenes (34.84%), cyclo-alkanes (9.87%), cyclo-alkenes (3.07), branched-chain alkanes (2.42%), branched-chain alkenes (0.88%).	^[51]
natural clay with kaolinite, hematite, smectite, quartz	PS	410	86.68	Fuel properties of the liquid fraction obtained showed a good resemblance with gasoline and diesel oil.	^[52]
Red clay (Auburn, Alabama, USA)	PS and LDPE (co-pyrolysis with a lignin)	500, 600, 700, 800	data not presented	The carbon yield of a lignin-derived compound, guaiacol, increased during co-pyrolysis of lignin with LDPE, and PS with red clay as a catalyst.	^[53]
Shwedaung clay, Mabisan clay	HDPE + LDPE + PS + PP + PET	210-380	65.81 (Shwedaung clay), 67.06 (Mabisan clay)	Fuel can be used internal combustion engine after distillation. Char can be used as solid fuel.	^[54]
Fe-restructured clay (Fe-RC)	PE + PP + PS + PVC + PET	450	83.73	High selectivity for the C₉–C₁₂ and C₁₃–C₁₉ oil fractions, which are the major constituents of kerosene and diesel fuel.	^[55]
Romanian natural clays: Vadu Crişului clay and Lugoj clay	PS + PET + PVC	420	62.18 (Vadu Crişului clay), 54.98 (Lugoj clay)	The liquid products contained monoaromatic compounds such as styrene, toluene, ethylbenzene, or alpha-methylstyrene.	^[56]

References

Li, K.; Lei, J.; Yuan, G.; Weerachanchai, P.; Wang, J.-Y.; Zhao, J.; Yang, Y. Fe-, Ti-, Zr- and Al-Pillared Clays for Efficient Catalytic Pyrolysis of Mixed Plastics. Chem. Eng. J. 2017, 317, 800–809.
Giese, R.F. Kaolin Group Minerals. In Sedimentology; Springer: Dordrecht, The Netherlands, 1978; pp. 651–655.
Liu, M.; Zhuo, J.K.; Xiong, S.J.; Yao, Q. Catalytic Degradation of High-Density Polyethylene over a Clay Catalyst Compared with Other Catalysts. Energy Fuels 2014, 28, 6038–6045.
Kumar, S.; Singh, R.K. Optimization of Process Parameters by Response Surface Methodology (RSM) for Catalytic Pyrolysis of Waste High-Density Polyethylene to Liquid Fuel. J. Environ. Chem. Eng. 2014, 2, 115–122.
Panda, A.K.; Singh, R.K. Thermo-Catalytic Degradation of Low Density Polyethylene to Liquid Fuel over Kaolin Catalyst. Int. J. Environ. Waste Manag. 2014, 13, 104.
Luo, W.; Fan, Z.; Wan, J.; Hu, Q.; Dong, H.; Zhang, X.; Zhou, Z. Study on the Reusability of Kaolin as Catalysts for Catalytic Pyrolysis of Low-Density Polyethylene. Fuel 2021, 302, 121164.
Soliman, A.; Farag, H.A.; Nassef, E.; Amer, A.; ElTaweel, Y. Pyrolysis of Low-Density Polyethylene Waste Plastics Using Mixtures of Catalysts. J. Mater. Cycles Waste Manag. 2020, 22, 1399–1406.
Khan, K.; Hussain, Z. Comparison of the Catalytic Activity of the Commercially Available Clays for the Conversion of Waste Polyethylene into Fuel Products. J. Chem. Soc. Pakistan 2011, 33, 956–959.
Erawati, E.; Hamid; Martenda, D. Kinetic Study on the Pyrolysis of Low-Density Polyethylene (LDPE) Waste Using Kaolin as Catalyst. IOP Conf. Ser. Mater. Sci. Eng. 2020, 778, 012071.
Attique, S.; Batool, M.; Yaqub, M.; Goerke, O.; Gregory, D.H.; Shah, A.T. Highly Efficient Catalytic Pyrolysis of Polyethylene Waste to Derive Fuel Products by Novel Polyoxometalate/Kaolin Composites. Waste Manag. Res. 2020, 38, 689–695.
Attique, S.; Batool, M.; Jalees, M.I.; Shehzad, K.; Farooq, U.; Khan, Z.; Ashraf, F.; Shah, A.T. Highly Efficient Catalytic Degradation of Low-Density Polyethylene Using a Novel Tungstophosphoric Acid/Kaolin Clay Composite Catalyst. Turkish J. Chem. 2018, 42, 684–693.
Hakeem, I.G.; Aberuagba, F.; Musa, U. Catalytic Pyrolysis of Waste Polypropylene Using Ahoko Kaolin from Nigeria. Appl. Petrochem. Res. 2018, 8, 203–210.
Uzair, M.A.; Waqas, A.; Khoja, A.H.; Ahmed, N. Experimental Study of Catalytic Degradation of Polypropylene by Acid-Activated Clay and Performance of Ni as a Promoter. Energy Sources Part A Recover. Util. Environ. Eff. 2016, 38, 3618–3624.
Panda, A.K.; Singh, R. Catalytic Performances of Kaoline and Silica Alumina in the Thermal Degradation of Polypropylene. J. Fuel Chem. Technol. 2011, 39, 198–202.
Panda, A.K.; Singh, R. Conversion of Waste Polypropylene to Liquid Fuel Using Acid-Activated Kaolin. Waste Manag. Res. J. Sustain. Circ. Econ. 2014, 32, 997–1004.
Panda, A.K.; Singh, R. Experimental Optimization of Process for the Thermo-Catalytic Degradation of Waste Polypropylene to Liquid Fuel. Adv. Energy Eng. 2013, 1, 74–84.
Uzair, M.A.; Waqas, A.; Afzal, A.; Ansari, S.H.; Anees ur Rehman, M. Application of Acid Treated Kaolin Clay for Conversion of Polymeric Waste Material into Pyrolysis Diesel Fuel. In Proceedings of the 2014 International Conference on Energy Systems and Policies (ICESP), Islamabad, Pakistan, 24–26 November 2014; pp. 1–4.
Ribeiro, A.M.; Machado Júnior, H.F.; Costa, D.A. Kaolin and Commercial fcc Catalysts in the Cracking of Loads of Polypropylene under Refinary Conditions. Braz. J. Chem. Eng. 2013, 30, 825–834.
Hadi, B.; Sokoto, A.M.; Garba, M.M.; Muhammad, A.B. Effect of Neat Kaolin and Cuo/Kaolin on the Yield and Composition of Products from Pyrolysis of Polystyrene Waste. Energy Sources Part A Recover. Util. Environ. Eff. 2017, 39, 148–153.
Eze, W.U.; Madufor, I.C.; Onyeagoro, G.N.; Obasi, H.C.; Ugbaja, M.I. Study on the Effect of Kankara Zeolite-Y-Based Catalyst on the Chemical Properties of Liquid Fuel from Mixed Waste Plastics (MWPs) Pyrolysis. Polym. Bull. 2021, 78, 377–398.
Auxilio, A.R.; Choo, W.-L.; Kohli, I.; Chakravartula Srivatsa, S.; Bhattacharya, S. An Experimental Study on Thermo-Catalytic Pyrolysis of Plastic Waste Using a Continuous Pyrolyser. Waste Manag. 2017, 67, 143–154.
Cho, K.-H.; Jang, B.-S.; Kim, K.-H.; Park, D.-W. Performance of Pyrophyllite and Halloysite Clays in the Catalytic Degradation of Polystyrene. React. Kinet. Catal. Lett. 2006, 88, 43–50.
Altaner, S.P. Smectite Group. In Sedimentology; Springer: Dordrecht, The Netherlands, 1978; pp. 1120–1124.
Elordi, G.; Olazar, M.; Castaño, P.; Artetxe, M.; Bilbao, J. Polyethylene Cracking on a Spent FCC Catalyst in a Conical Spouted Bed. Ind. Eng. Chem. Res. 2012, 51, 14008–14017.
Faillace, J.G.; de Melo, C.F.; de Souza, S.P.L.; da Costa Marques, M.R. Production of Light Hydrocarbons from Pyrolysis of Heavy Gas Oil and High Density Polyethylene Using Pillared Clays as Catalysts. J. Anal. Appl. Pyrolysis 2017, 126, 70–76.
Hussain, Z.; Khan, K.; Jan, M.; Shah, J. Conversion of Low Density Polyethylene into Fuel Products Using Gachi Clay as Catalyst. J. Chem. Soc. Pakistan 2010, 32, 240–244.
Qureshi, M.; Nisar, S.; Shah, R.; Salman, H. Studies of Liquid Fuel Formation from Plastic Waste by Catalytic Cracking over Modified Natural Clay and Nickel Nanoparticles. Pak. J. Sci. Ind. Res. Ser. A Phys. Sci. 2020, 63, 79–88.
hamouda, A.; Abdelrahman, A.; Zaki, A.; Mohamed, H. Studying and Evaluating Catalytic Pyrolysis of Polypropylene. Egypt. J. Chem. 2021, 64, 2593–2605.
Dewangga, P.B.; Rochmadi; Purnomo, C.W. Pyrolysis of Polystyrene Plastic Waste Using Bentonite Catalyst. IOP Conf. Ser. Earth Environ. Sci. 2019, 399, 012110.
Ahmad, I.; Khan, M.I.; Khan, H.; Ishaq, M.; Tariq, R.; Gul, K.; Ahmad, W. Influence of Metal-Oxide-Supported Bentonites on the Pyrolysis Behavior of Polypropylene and High-Density Polyethylene. J. Appl. Polym. Sci. 2015, 132, 41221.
Narayanan, K.S.; Anand, R.B. Experimental Investigation on Optimisation of Parameters of Thermo-Catalytic Cracking Process for H.D.P.E. & P.P. Mixed Plastic Waste with Synthesized Alumina-Silica Catalysts. Appl. Mech. Mater. 2014, 592–594, 307–311.
Sembiring, F.; Purnomo, C.W.; Purwono, S. Catalytic Pyrolysis of Waste Plastic Mixture. IOP Conf. Ser. Mater. Sci. Eng. 2018, 316, 012020.
Budsaereechai, S.; Hunt, A.J.; Ngernyen, Y. Catalytic Pyrolysis of Plastic Waste for the Production of Liquid Fuels for Engines. RSC Adv. 2019, 9, 5844–5857.
Panda, A.K. Thermo-Catalytic Degradation of Different Plastics to Drop in Liquid Fuel Using Calcium Bentonite Catalyst. Int. J. Ind. Chem. 2018, 9, 167–176.
Borsella, E.; Aguado, R.; De Stefanis, A.; Olazar, M. Comparison of Catalytic Performance of an Iron-Alumina Pillared Montmorillonite and HZSM-5 Zeolite on a Spouted Bed Reactor. J. Anal. Appl. Pyrolysis 2018, 130, 320–331.
De Stefanis, A.; Cafarelli, P.; Gallese, F.; Borsella, E.; Nana, A.; Perez, G. Catalytic Pyrolysis of Polyethylene: A Comparison between Pillared and Restructured Clays. J. Anal. Appl. Pyrolysis 2013, 104, 479–484.
Olivera, M.; Musso, M.; De León, A.; Volonterio, E.; Amaya, A.; Tancredi, N.; Bussi, J. Catalytic Assessment of Solid Materials for the Pyrolytic Conversion of Low-Density Polyethylene into Fuels. Heliyon 2020, 6, e05080.
Gobin, K.; Manos, G. Polymer Degradation to Fuels over Microporous Catalysts as a Novel Tertiary Plastic Recycling Method. Polym. Degrad. Stab. 2004, 83, 267–279.
Manos, G.; Yusof, I.Y.; Gangas, N.H.; Papayannakos, N. Tertiary Recycling of Polyethylene to Hydrocarbon Fuel by Catalytic Cracking over Aluminum Pillared Clays. Energy Fuels 2002, 16, 485–489.
Manos, G.; Yusof, I.Y.; Papayannakos, N.; Gangas, N.H. Catalytic Cracking of Polyethylene over Clay Catalysts. Comparison with an Ultrastable Y Zeolite. Ind. Eng. Chem. Res. 2001, 40, 2220–2225.
Lal, S.; Anisia, K.S.; Jhansi, M.; Kishore, L.; Kumar, A. Development of Heterogeneous Catalyst by Ionically Bonding Macrocyclic Zr–Zr Complex to Montmorillonite Clay for Depolymerization of Polypropylene. J. Mol. Catal. A Chem. 2007, 265, 15–24.
Cho, K.-H.; Cho, D.-R.; Kim, K.-H.; Park, D.-W. Catalytic Degradation of Polystyrene Using Albite and Montmorillonite. Korean J. Chem. Eng. 2007, 24, 223–225.
Tomaszewska, K.; Kałużna-Czaplińska, J.; Jóźwiak, W. Thermal and Thermo-Catalytic Degradation of Polyolefins as a Simple and Efficient Method of Landfill Clearing. PJCT 2010, 12, 50–57.
Gong, J.; Liu, J.; Jiang, Z.; Chen, X.; Wen, X.; Mijowska, E.; Tang, T. Converting Mixed Plastics into Mesoporous Hollow Carbon Spheres with Controllable Diameter. Appl. Catal. B Environ. 2014, 152–153, 289–299.
Kebritchi, A.; Nekoomansh, M.; Mohammadi, F.; Khonakdar, H.A. Effect of Microstructure of High Density Polyethylene on Catalytic Degradation: A Comparison Between Nano Clay and FCC. J. Polym. Environ. 2018, 26, 1540–1549.
Marcilla, A.; Gómez, A.; Menargues, S.; Ruiz, R. Pyrolysis of Polymers in the Presence of a Commercial Clay. Polym. Degrad. Stab. 2005, 88, 456–460.
Chen, Z.; Wang, Y.; Sun, Z. Application of Co Ni Intercalated Vermiculite Catalyst in Pyrolysis of Plastics. J. Phys. Conf. Ser. 2021, 1885, 032030.
Zhou, N.; Dai, L.; Lv, Y.; Li, H.; Deng, W.; Guo, F.; Chen, P.; Lei, H.; Ruan, R. Catalytic Pyrolysis of Plastic Wastes in a Continuous Microwave Assisted Pyrolysis System for Fuel Production. Chem. Eng. J. 2021, 418, 129412.
Patil, L.; Varma, A.K.; Singh, G.; Mondal, P. Thermocatalytic Degradation of High Density Polyethylene into Liquid Product. J. Polym. Environ. 2018, 26, 1920–1929.
Hussain, Z.; Khan, K.; Jan, M.; Shah, J. Conversion of Low Density Polyethylene into Fuel Products Using Indian Fuller’s Earth as Catalyst. J. Chem. Soc. Pak. 2010, 32, 790–793.
Nguyen, L.T.T.; Poinern, G.E.J.; Le, H.T.; Nguyen, T.A.; Tran, C.M.; Jiang, Z. A LaFeO3 Supported Natural-Clay-Mineral Catalyst for Efficient Pyrolysis of Polypropylene Plastic Material. Asia-Pac. J. Chem. Eng. 2021, 16, e2695.
Ali, G.; Nisar, J.; Shah, A.; Farooqi, Z.H.; Iqbal, M.; Shah, M.R.; Ahmad, H.B. Production of Liquid Fuel from Polystyrene Waste: Process Optimization and Characterization of Pyrolyzates. Combust. Sci. Technol. 2021, 1–14.
Patil, V.; Adhikari, S.; Cross, P. Co-pyrolysis of Lignin and Plastics Using Red Clay as Catalyst in a Micro-Pyrolyzer. Bioresour. Technol. 2018, 270, 311–319.
Kyaw, K.; Hmwe, C. Effect of Various Catalysts on Fuel Oil Pyrolysis Process of Mixed Plastic Wastes. Int. J. Adv. Eng. Technol. 2015, 8, 794.
Lei, J.; Yuan, G.; Weerachanchai, P.; Lee, S.W.; Li, K.; Wang, J.-Y.; Yang, Y. Investigation on Thermal Dechlorination and Catalytic Pyrolysis in a Continuous Process for Liquid Fuel Recovery from Mixed Plastic Wastes. J. Mater. Cycles Waste Manag. 2018, 20, 137–146.
Filip, M.; Pop, A.; Perhaiţa, I.; Trusca, R.; Rusu, T. The Effect of Natural Clays Catalysts on Thermal Degradation of a Plastic Waste Mixture. Adv. Eng. Forum 2013, 8–9, 103–114.

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Subjects: Polymer Science

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Olga Lebedeva

Evgeniy Seliverstov

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Update Date: 08 Jun 2022

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