Catalytic Co-pyrolysis Research Articles

Fast and ex Situ Catalytic Copyrolysis of Switchgrass and Waste Polyethylene

Fast and ex Situ Catalytic Copyrolysis of Switchgrass and Waste Polyethylene

Production of diesel-like fuel by catalytic co-pyrolysis of waste cooking oil and waste lubricating oil—an alternate energy source

Production of diesel-like fuel by catalytic co-pyrolysis of waste cooking oil and waste lubricating oil—an alternate energy source

Catalytic co-pyrolysis of yellow poplar and HDPE using MOF-incorporated HY zeolite catalysts

Catalytic co-pyrolysis of yellow poplar and high-density polypropylene (HDPE) was conducted using metal oxide on hydrogen y-type (HY) zeolite to selectively produce monoaromatic hydrocarbons. The reaction was investigated using a tandem micro-reactor connected to a gas chromatography–mass spectrometry (GC–MS) system, encompassing both in-situ and ex-situ studies. Fe oxide/HY and Cu oxide/HY catalysts, prepared via a metal–organic framework (MOF)-incorporated technique, demonstrated excellent metal dispersion and enhanced electron density. The Cu oxide/HY catalyst showed significant production of benzene, toluene, ethylbenzene, and xylene, reaching up to 28% in in-situ studies. Owing to its strong acid sites, this catalyst facilitated the formation of aromatic compounds. In ex-situ studies, furan and acetaldehyde were consumed through the Diels–Alder reaction. The increase in aromatic compounds was highlighted by a synergistic effect percentage as high as 175%. The mechanism of aromatic formation was elucidated through dealkylation, Diels–Alder, and aromatization reactions. The Cu oxide/HY catalyst, combined with the MOF-incorporated preparation technique presents a promising system for catalytic co-pyrolysis of biomass and HDPE. This approach will facilitate efficient and sustainable aromatic hydrocarbon production from renewable and plastic waste sources.

Catalytic pyrolysis of Padina sp. with ZSM-5 and Amberlyst-15 catalysts to produce aromatic-rich bio-oil

The growing demand for renewable energy has increased interest in bio-oil production from biomass, particularly through catalytic co-pyrolysis. However, research on marine biomass like Padina sp. is limited. This study investigates the catalytic co-pyrolysis of Padina sp. using ZSM-5 and Amberlyst-15 catalysts to enhance aromatic-rich bio-oil production. Systematic experiments were conducted with varying catalyst loadings (1 %, 2 %, and 3 %) and temperatures (400 °C, 500 °C, and 600 °C). GC/MS analysis revealed that Amberlyst-15 at 600 °C and 3 % loading achieved a 65 % aromatic hydrocarbon yield, surpassing ZSM-5, which reached 50 %. Additionally, the highest conversion efficiency, 50 %, was attained with Amberlyst-15 at 500 °C and 3 % loading. These findings highlight the viability of Padina sp. as a renewable biofuel source and emphasize the importance of catalyst selection and process optimization in refining bio-oil production techniques, suggesting that further improvements in catalyst compositions and parameters could advance sustainable bio-oil production for renewable energy.

Thermodynamic investigation and 4Es analysis of a VCR diesel engine using emulsified diesel with catalytic co-pyrolysis fuel derived from waste LDPE and Pongamia pinnata seeds

Global challenges for massive plastic waste disposal and regular decrement of conventional resources, converting plastic and biomass seeds waste into transportation-grade fuels through co-pyrolysis offer a better option for providing a promising solution. This investigation signifies a thermodynamic power cycle model, and 4Es (Energy, Exergy, Environmental, Economic) analysis of a direct injection unmodified diesel engine powered with various blends of test fuels derived from thermo-catalytic co-pyrolysis of low-density polyethylene (LDPE) wastes and Pongamia pinnata seeds at 500 °C with calcium oxide as catalyst, mixed with diesel. The fuel mixtures of pure diesel and pyrolytic test fuels are utilized for diesel engine testing with varying compression ratio. The synergistic effects of major parameters such as full engine load, varying compression ratios (16:1, 17:1, 18:1, and 19:1), and fuel blends (10, 20, 30, and 40 %) are considered for engine run. The Brake thermal energy was found to increase for the 20 % blend at 6.6 % (40 % load) in comparison to pure diesel. Also, the Brake specific fuel consumption was the least for the same blend, 0.31 kg/kWh at 18:1 CR. The smoke was also found to have lowered by 22 % for the 20 % blend in comparison to pure diesel. At a compression ratio of 18:1, the NOx formation also decreased by approximately 1.4 % in comparison to the pure diesel for almost all considered fuel blends. The fuel efficiency was observed to increase for the 20 % blend compared to pure diesel by 20 %. The cost and exergy destruction analysis also confirmed the D80PB20 to have the least and maximum values respectively for both parameters. The energy, exergy, emission, and economic (4Es) analysis confirmed the suitability of blended fuels for achieving improved engine performance and emissions. In addition, the economic and fuel sustainability analysis foster the techno-economic feasibility of the test fuels as compared to conventional diesel fuel.

Chitosan-assisted reassembled hierarchical HZSM-5 for selective production of monocyclic aromatics in catalytic co-pyrolysis of biomass and plastic

Biomass presents significant potential as an alternative template agent for assisting zeolites in developing new pore structure during recrystallization to enhance their catalytic performance. In this study, a new hierarchical HZSM-5 was synthesized through the in-situ reassembly of alkali-treated HZSM-5 with chitosan as an assisting agent. The impact of chitosan dosage on the catalytic performance of the hierarchical HZSM-5, as well as the influences of temperature, catalyst dosage, and corn stover (CS) to high-density polyethylene (HDPE) mass ratio on the content and selectivity of monocyclic aromatic hydrocarbons (MAHs) during the catalytic co-pyrolysis process, were thoroughly investigated. The results indicated that chitosan exhibited great potential as a template in the reassembly of hierarchical HZSM-5 during NaOH treatment, promoting the formation of weak acid sites and micro-mesoporous structures. Compared to the parent HZSM-5, the chitosan-assistant reassembled hierarchical HZSM-5 significantly enhanced the production of MAHs and inhibited the formation of polycyclic aromatic hydrocarbons (PAHs). The highest carbon yield of MAHs reached 36.9 % at 550 °C with a chitosan dosage of 15 %. Furthermore, the chitosan-modified HZSM-5 notably enhanced the synergistic production of MAHs by 38.2 %, while preventing the formation of PAHs and coke. This study contributes insights into the sustainable synthesis of hierarchical HZSM-5 for improved production of high-value products in the co-pyrolysis of biomass and waste plastics.

In-Depth Study on Synergic Interactions and Thermo-Kinetic Analysis of (Wheat Straw and Woody Sawdust) Biomass Co-Pyrolysis over Mussel Shell-Derived CaO Catalyst Using Coats–Redfern Method

The behavior of wheat straw biomass (WS), woody sawdust biomass (WB), and their blends during catalytic co-pyrolysis are analyzed in the presence of CaO catalyst, which is obtained from the calcination of mussel shells. Synergy analysis of blends and pure materials is measured by studying the difference between theoretical and experimental values of wt.%/min, (RL%), and (WL%), which correspond to maximum weight loss rate, residue left, and weight loss, respectively. The Coats–Redfern method is utilized for evaluating the thermo-kinetic properties. The chemical reaction order model F1 is the best model that describes the Ea of 60.05 kJ/mol and ∆H, ∆G, and ∆S values of 55.03 kJ/mol, 162.26 kJ/mol, and −0.18 kJ/mol.K, respectively, for the optimum blend 80WS−20WB, reducing the thermo-kinetic properties. Model D3 showed better results for the Ea, ∆H, ∆G, and ∆S for the 5% CaO blend, which certified the viability of co-pyrolysis of WS and WB, while DTG indicated that exothermic and endothermic reactions occur together.

Synthesis of Bio-Oil via Catalytic Co-Pyrolysis of Cotton Fabric Waste and Polypropylene Plastic Waste

The growing energy demand and rising environmental concerns pose severe difficulties for future generations in maintaining energy sustainability. Therefore, it is critical to explore alternative green energy sources. Hence, this study synthesized renewable bio-oil by utilizing biomass of cotton fabric waste (CFW) and polypropylene plastic waste (PPW) as feedstocks. Titanium and alumina extracted from industrial solid waste (Ti-EA) were selected as catalysts due to their active sites promoting co-pyrolysis reaction towards bio-oil formation. The Ti-EA catalyst was prepared via the wet impregnation method at different calcination times. The bio-oil was synthesized via co-pyrolysis of CFW and PPW in a fixed bed reactor at the reaction temperature of 600 °C for 1 h. The effects of the catalyst calcination time were evaluated based on the bio-oil yield and product distribution. Moreover, the catalysts were characterized by BET and FTIR. The findings show that the Ti-EA catalyst calcined at 4 h (Ti-EA-4) obtained the highest bio-oil yield of 68% whereas calcination at 6 h (Ti-EA-6) gave the lowest yield of 28%. The BET shows that the Ti-EA-4 catalyst has a higher surface area of 121.6 m2/g than the Ti-EA-6 catalyst of 96.74 m2/g. This indicates that surface area is an important characteristic that promotes efficient catalytic activity for bio-oil production. Meanwhile, FTIR results show that the catalysts have similar surface functional groups mainly O-H stretching vibrations. Overall, Ti-EA catalyst calcined at 4 h has exhibited good performance in producing bio-oil via co-pyrolysis of CFW and PPW. Thus, Ti-EA catalyst has the potential to produce bio-oil as fuel, which contributes towards waste to energy conversion and environmental preservation.

Study on biomass and polymer catalytic co-pyrolysis product characteristics using machine learning and shapley additive explanations (SHAP)

Biomass and polymer catalytic co-pyrolysis can convert waste into higher-quality fuels, thereby reducing the use of fossil fuels to some extent. However, this process is an extremely complex thermochemical conversion, influenced by numerous factors such as feedstock properties, operational variables, and catalyst. Currently, experimental methods require substantial time and resource investment. Machine learning (ML) can fit and match input and output features based on existing data, achieving extremely high accuracy in the co-pyrolysis process. This study applies advanced ML models to study the biomass and polymer catalytic co-pyrolysis process, with a focus on the yield of pyrolysis products and the variations of the oxygen-containing components in the pyrolysis oil. The best-performing model is used for feature analysis of the correlation between inputs and outputs, based on game theory SHAP analysis. The results indicate a significant negative correlation between the polymer addition ratio and the generation of oxygen-containing components during the co-pyrolysis process. The addition of catalysts promotes the generation of pyrolysis gas during co-pyrolysis but suppresses the yield of pyrolysis oil. Additionally, catalysts significantly inhibit the formation of oxygenates in the pyrolysis oil. The XGBR model shows the highest performance in predicting pyrolysis oil yield, achieving R2 values of 0.98 during training phase and 0.91 during testing phase. The GBR model performs well in predicting the oxygenate composition of pyrolysis oil from small datasets.

Insights into catalytic co-pyrolysis of spent coffee grounds and high density polyethylene (HDPE) using acid mine drainage (AMD) treated sludge based catalyst: Analysis of kinetics, mechanism and thermodynamic properties

The present study aims to investigate the catalytic effect of acid mine drainage (AMD) treated sludge based catalyst on the co-pyrolysis of spent coffee grounds and HDPE. The sludge was generated during the treatment of AMD using eggshell and hydrogen peroxide. Theromogravimetric analysis of pyrolysis of spent coffee grounds (SC), HDPE (High density polyethylene), blend of spent coffee grounds and HDPE (SC+HDPE) in the ratio of 1:1, and blended feedstock with sludge derived catalyst (SC+HDPE_AMDC) (1:1 wt. ratio) was conducted at various heating rates of 10 °C/min, 20 °C/min, 30 °C/min and 40 °C/min respectively. Iso-conversional models such as Ozawa Flynn Wall (OFW), Kissinger Akahira Sunose (KAS), Friedman, and Starink were utilized for the determination of activation energy (Ea) of the process. The results showed that using AMD treated sludge based catalyst to the pyrolysis process, enhances its overall efficacy by lowering the activation energy (Ea) (OFW- Ea: 209.11 to 177.14 KJ/mol, KAS-Ea: 208.30 to 173.06 KJ/mol, Friedman- Ea:210.54 to 176.28 KJ/mol, and Starink- Ea:208.60 to 173.44 KJ/mol). Criado's z-master plot (CZMP) method was utilized to analyze the mechanism of the reaction. The pre-exponential factor and thermodynamic parameters were also evaluated. It is concluded that the incorporation of sludge based catalyst (AMDC) lowered enthalpy and randomness of system. Catalytic co-pyrolysis requires less energy, making it more environmental friendly choice for the sustainable processing of biomass and plastics. The present investigation will aid in the design, optimization and scalability.

An experimental investigation on performance, emission and combustion characteristics of IC engine using liquid fuel produced through catalytic co-pyrolysis of pressed oil cake and mixed plastics with the addition of nanoparticles

The study focuses on using a combination of diesel and a liquid fuel derived from the co-pyrolysis of pressed neem cake (PNC) and mixed waste plastics (MWP) containing waste polyethylene terephthalate (PET) and low density polyethylene (LDPE) in equal amounts with the help of cupric oxide (CuO) catalyst. The engine analysis was carried out using diesel and five different blends of co-pyrolysis oil with diesel in proportions of 20 % (20 % pyrolysis oil + 80 % diesel = PD20), 40 % (PD40), 50 % (PD50) and 100 % pyrolysis oil (PD100), respectively. Initially, the co-pyrolysis oil was produced using PNC and MWP in a ratio of 1:2 under different operating temperatures between 350 °C and 650 °C. The process temperature was optimized to yield maximum liquid oil, and the characterization study was performed. In addition to that, CeO2 nanoadditives were used to improve the properties of PD20 fuel. Different dosages of nanoadditives were blended with PD20 to prepare PD20@25 (PD20 + 25 ppm CeO2), PD20@50, PD20@75, and PD20@100. The objective of the study is to assess the performance, emission, and combustion characteristics of a diesel engine utilizing co-pyrolysis oil-diesel blend by including the nanoadditives. The analysis was carried out on a single-cylinder water-cooled diesel engine mounted with an eddy current dynamometer. The experiments demonstrated that the combination of PD20 and 50 ppm CeO2 resulted in a 6 % increase in thermal efficiency when compared to other blended fuels and diesel. When compared to all fuels, the PD20@50 produced a higher decrease in CO and HC emissions by roughly 30 and 6.2 %, respectively. The combustion analysis showed that the heat release rate (HRR) and maximum cylinder pressure were also found to have improved by adding nanoparticles.

Microwave catalytic co-pyrolysis of microalgae and high density polyethylene over activated carbon supported bimetallic: Characteristics and bio-oil analysis

Three activated carbon (AC) supported bimetallic catalysts (Ce-Fe/AC, Ce-Ni/AC, Ce-Cu/AC) were prepared, and the catalysts' impacts on the microwave co-pyrolysis of Chlorella vulgaris (C. vulgaris) and high density polyethylene (HDPE) (mixing ratio of 1:1, C1HP1) were explored. The findings indicated that the catalysts promoted the co-pyrolysis of C1HP1 substantially at 40 % and 50 % additions. The minimum reaction time (2945 s) was observed at 40 % Ce–Fe/AC. Compared to the C1HP1 group, Ce-Fe/AC groups exhibited a pronounced promotional impact on bio-oil production, with the maximum bio-oil yield (25.8 %) catalyzed by 30 % Ce–Fe/AC. Furthermore, the catalyst's high hydrogenation activity and deoxygenation promoted the formation of H2O, NH3 and HCN, achieving over 40 % efficiencies in deoxygenation and denitrification for bio-oil. 40 % Ce–Cu/AC exhibited superior performance with the highest hydrocarbon (67.43 %) and aromatic hydrocarbon content (50.75 %), as well as leading deoxygenation (44.38 %) and nitrogen removal (58.63 %) efficiency among the AC supported bimetallic catalysts.

Hierarchical HZSM-5 catalysts enhancing monocyclic aromatics selectivity in co-pyrolysis of wheat straw and polyethylene mixture

The limitation in bio-oil quality hampers its further utilization in the fuel or chemical industry. This study employed a combination of tetra propylammonium hydroxide (TPAOH) and NaOH solutions for HZSM-5 desilication to enhance the yield of monocyclic aromatic hydrocarbons in the catalytic co-pyrolysis of wheat straw with polyethylene. Results revealed hierarchical HZSM-5, prepared with equal mole concentrations of NaOH and TPAOH, exhibited optimal catalytic performance. The bio-oil from this process had an aromatic content of 72 %, with monocyclic aromatic hydrocarbons (MAHs) constituting 56.26 %. Further optimization was achieved through iron modification of hierarchical HZSM-5. The addition of 0.5 % iron-modified hierarchical HZSM-5 increased the aromatic hydrocarbons to 80.57 %, with BTX compounds (benzene, toluene, and xylene) reaching a selectivity of 61.9 %. This approach reduced polycyclic aromatic hydrocarbons (PAHs), contributing to less coke formation, presenting a promising method for high-quality bio-oil.

Electrocatalytic Conversion of Phenol to Cyclohexane Using Pt and Ru-Based Catalysts

The production of renewable fuels has become necessary as fossil fuels continue to deplete.1 Pyrolysis of biomass to liquid fuels has emerged as a promising solution due to the possibility of conversion of high carbon content feedstocks into fuel. Pyrolysis oils, however, struggle from low yields and increased heteroatom content.2 In order to solve this problem a second upgrading step is needed to increase the fuel’s hydrogen content and remove heteroatoms. Conventional oil upgrading through thermochemical processes is an option using high temperatures (>300 °C) and high-pressure hydrogen (10-20MPa).3 Electrochemical upgrading of bio-oils represents a novel avenue for the conversion of bio-oils to usable fuels or commodity chemicals under mild condition which requires milder temperatures (30-80 °C) and generates the hydrogen in situ through the water splitting reaction.3 Though initial results on electrocatalytic upgrading have been promising, few studies report appreciable yields of fully deoxygenated products and the efficiency remains low at high current densities.3 This work focuses on the upgrading of phenol as a bio-oil model compound. ECH of phenol was investigated in a custom electrochemical cell (H-Cell), with a solvent trap for the collection and quantification of volatile organic products. Efficient ECH conversion of phenol to cyclohexane was demonstrated and the primary factors impacting the selective production of cyclohexane were studied. Multiple variables, including catalyst type, electrolyte composition and concentration, and cathodic potential were investigated to determine their influence on ECH reaction rate, selectivity, and efficiency. The results obtained show that lab-synthesized, bi-metallic PtRu-C catalyst results in the highest specific ECH rate of 23.52 mol h-1 g-1 metal in comparison to 19.92 mol h-1 g-1 metal, 15.84 mol h-1 g-1 metal and 4.64 mol h-1 g-1 metal, measured with a commercial PtRu-C and mono-metallic Pt-C and Ru-C catalysts, respectively. In addition, the lab synthesized PtRu-C catalyst achieved > 30% selectivity towards cyclohexane, which is among the highest reported in literature to date. Constant potential experiments showed that the cyclohexane was 4.6% higher at -0.46 V vs Ag/AgCl than -0.28 V vs Ag/AgCl indicating cyclohexane selectivity is weakly dependent on cathodic potential. To improve the mechanistic understanding of phenol ECH, operando Raman spectroscopy was explored, finding strong evidence for cyclohexanone reaction intermediates.References(1) Zhang, X.; Lei, H.; Chen, S.; Wu, J. Catalytic Co-Pyrolysis of Lignocellulosic Biomass with Polymers: A Critical Review. Green Chemistry. 2016. https://doi.org/10.1039/c6gc00911e.(2) Zhang, B.; Zhong, Z.; Min, M.; Ding, K.; Xie, Q.; Ruan, R. Catalytic Fast Co-Pyrolysis of Biomass and Food Waste to Produce Aromatics: Analytical Py-GC/MS Study. Bioresour. Technol. 2015, 189. https://doi.org/10.1016/j.biortech.2015.03.092.(3) Chen, G.; Liang, L.; Li, N.; Lu, X.; Yan, B.; Cheng, Z. Upgrading of Bio-Oil Model Compounds and Bio-Crude into Biofuel by Electrocatalysis: A Review. ChemSusChem. 2021. https://doi.org/10.1002/cssc.202002063. Figure 1

Synthesis of benzoic acid from catalytic co-pyrolysis of waste wind turbine blades and biomass and their kinetic analysis

This work aims to study the catalytic co-pyrolysis of waste wind turbine blades (WTB: consists of fiberglass/unsaturated polyester resin) and woody biomass (WB) over ZSM-5 and Y-type zeolite catalysts for the production of benzoic acid. The experiments were performed on an equal combination of WTB and WB (WTB/WB) and a fixed amount of catalyst (50 wt%) using a thermogravimetric (TG) analyser at 10, 20 and 30 °C/min. The evolved products from the catalytic co-pyrolysis process were recognized using TG-FTIR and GC/MS. The kinetic and thermodynamic characteristics of catalytic co-pyrolysis was studied using various linear and nonlinear approaches. Also, the decomposition curves were predicted mathematically using an artificial neural network algorithm. The results revealed that the mixture was decomposed in the presence of both catalysts in the form of dual decomposition peaks at 361–374 °C and 428–443 °C, respectively. Based on TG-FTIR results, the CO stretching and carbon dioxide clusters were their main functional groups. While the GC-MS analysis revealed that the released vapours were completely free of toxic styrene (the main compound of resin) and the catalytic co-pyrolysis treatment succeeded in converting it into highly abundant benzoic acid, especially at 10 °C/ min, with an estimated 71.4 % (ZSM-5) and 64 % (Y-type). Whereas the activation energy was estimated at 262–295 kJ/mol (ZSM-5) and 319–357 kJ/mol (Y-type) with almost similar reaction complexity when compared to the case of absence of catalysts. Finally, the developed ANN algorithm showed high efficiency in predicting TG decomposition zones for both WTB/WB mixtures over zeolite catalysts with R2 more than 0.99. These results demonstrate that WB and zeolite catalysts can be used for upgrading the pyrolysis oil of WTB and eliminate its toxic styrene and convert it into benzoic acid and other aromatic hydrocarbons compounds (such as benzene, alanine, and 2-Propanamine).

Co-pyrolysis of refinery oil sludge with biomass and spent fluid catalytic cracking catalyst for resource recovery.

Catalytic co-pyrolysis of two different refinery oily sludge (ROS) samples was conducted to facilitate resource recovery. Non-catalytic pyrolysis in temperatures ranging from 500 to 600°C was performed to determine high oil yields. Higher temperatures enhanced the oil yields up to ~ 24 wt%, while char formation remained unchanged (~ 45%) for S1. Conversely, S2 exhibited a notably lower oil yield (~ 4 wt%) than S1. Pyrolysis oil of S1 consisted of phenolics (~ 50% at 600°C) whereas hydrocarbons were predominant in S2 oil (~ 80% at 600°C). Catalytic pyrolysis of S1 did not exhibit a substantial impact on oil yields but the oil composition varied significantly. High hydrocarbons, phenolics, and aromatics were obtained with molecular sieve (MS), metal slag, and ZSM-5, respectively. Catalytic co-pyrolysis of S2 with sawdust (SD) in the presence of MS enhanced the oil yield, and the resulting oil consisted of high hydrocarbons (~ 54%) and aromatics (~ 44%).

Synthesis of metal-free heteroatom (N, P, O, and B) doped biochar catalysts for enhanced catalytic co-pyrolysis of walnut shells and palm oil fatty acid distillate to produce high-quality bio-oil

In the current study, sugarcane bagasse-derived biochar catalysts were synthesized by doping with metal-free heteroatoms including nitrogen, phosphorus, oxygen, and boron and their efficacy was tested for catalytic co-pyrolysis of walnut shells (WS) and palm oil fatty acid distillate (PFAD) using Py-GC/MS. The biochar catalysts’ properties and their effectiveness on co-pyrolytic bio-oil (overall product distribution, selectivity towards aliphatic and aromatic hydrocarbons, and carbon number ranges) were extensively examined. Among the various catalysts considered, boron-doped biochar (BCB) demonstrated effective performance due to an improved surface area, porosity, and acidity and resulted in a significantly increased hydrocarbon yield, particularly in the gasoline and diesel range, and preference for aromatic over aliphatic hydrocarbons. The optimum bio-oil quality was achieved at a feedstock-to-catalyst ratio of 2:1 and a pyrolysis temperature of 750 °C, with a hydrocarbon yield of 90.8 % and aromatic hydrocarbon selectivity of 63.5 %. Overall, the study underscores the role of BCB in fostering deoxygenation, decarboxylation, and aromatic selectivity via thermal and catalytic pathways, highlighting the potential of non-metallic doped biochars for bio-oil upgrading.

Catalytic Co-Pyrolysis of Oil Palm Frond and Plastic Waste into Liquid Fuel using Ni-CaO Catalyst

Catalytic Co-Pyrolysis of Oil Palm Frond and Plastic Waste into Liquid Fuel using Ni-CaO Catalyst

Catalytic co-pyrolysis behaviour and kinetics study of waste lignocellulosic non-edible seeds and Covid-19 plastic over Al2O3 catalyst

The current research centred on estimating kinetic parameters and examining the composition of pyrolysis vapours from neem seeds and COVID-19 waste nitrile gloves (NG) using Pyro-GC–MS. Owing to the intricacy of the co-pyrolysis process, kinetic parameters were studied using KAS, OFW, FM, and VZ models. Biomass and plastic were mixed in different proportions (1:1, 3:1, and 5:1), whereas feed to catalyst was mixed at 3:1, 5:1 and 8:1, respectively. The estimation of the kinetic parameters of co-pyrolysis of NMS and NG confirmed that the 3:1 ratio and the feeds-to-catalyst ratio at 5:1 were found to be most effective in producing maximum hot vapours. Moreover, the analysis of pyrolysis vapours confirmed that a ratio of 3:1 for (NMS to NG) and a ratio of 5:1 for feed to catalyst (NMS + NG(3:1) + Al2O3 (5:1) resulted in the highest production of hydrocarbons while decreasing the presence of acids and oxygenated compounds.

Catalytic co-pyrolysis of poplar tree and polystyrene with HZSM-5 and Fe/HZSM-5 for production of light aromatic hydrocarbons

The catalytic co-pyrolysis of biomass and plastic waste is a highly effective approach for the production of light aromatic hydrocarbons. In this study, catalytic co-pyrolysis experiments were conducted on poplar tree (PT) and polystyrene (PS) using pyrolyzer coupled with gas chromatography/mass spectrometry (Py-GC/MS). The experiments were carried out at a temperature of 550 °C and a mixing ratio of 1:1. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) techniques were employed for the characterization of HZSM-5 and Fe/HZSM-5 catalysts. The findings indicated that the metallic Fe in the HZSM-5 catalyst led to an enhanced production of monocyclic aromatic hydrocarbons (MAH) during the catalytic co-pyrolysis of PT and PS. The proportion of MAH in the products obtained from HZSM-5 and Fe/HZSM-5 catalyst was determined to be 85.84% and 90.87%, respectively. In the catalytic co-pyrolysis of biomass and plastic waste, several crucial reactions took place, including deoxidation, olefins aromatization, and Diels-Alder reaction between furans and olefins. In the presence of Fe metal, the HZSM-5 catalyst exhibited enhanced selectivity towards valuable MAH while effectively suppressing the formation of polycyclic aromatic hydrocarbons, resulting in an increase in MAH production to 90.87%.