Co-Pyrolysis of Hyphaene thebaica Shell-Waste Plastics Composite, and the Analysis of the Pyrolytic Oil Compositions

527 Nigerian Research Journal of Engineering and Environmental Sciences 10(2) 2025 pp. 527-534 p ISSN: 2635-3342; e ISSN: 2635-3350 Original Research Article Co-Pyrolysis of Hyphaene thebaica Shell-Waste Plastics Composite, and the Analysis of the Pyrolytic Oil Compositions *1Mohammed, H.I., 2Garba K., 1Isah, U.A., 1Taura, U.H. and 1Lawan, M.Z. 1Department of Chemical Engineering, University of Maiduguri, P.M.B 1069, Maiduguri, Nigeria. 2Department of Chemical Engineering, Abubakar Tafawa Balewa University, P.M.B 0248, Bauchi, Nigeria. *[email protected] http://doi.org/10.5281/zenodo.18061802 ARTICLE INFORMATION ABSTRACT Article history: Received 05 Oct. 2025 Revised 28 Oct. 2025 Accepted 08 Nov. 2025 Available online 30 Dec. 2025 The need to produce enhanced pyrolytic oil from biomass for specific applications is necessary to achieve sustainable energy and chemicals. Bottled water and beverage waste plastics are common terrestrial and aquatic pollutants. This research aimed to produce pyrolytic oil from the Hyphaene thebaica shell-waste plastics and evaluate its pyrolytic oil compositions. The composite of the Hyphaene thebaica shell-waste plastics (HTSWP) was prepared and characterized using thermogravimetric analysis to determine the devolatilisation behaviour. The HTSWP was pyrolyzed, and pyrolytic oil was obtained. The pyrolytic oil was characterized using Fourier Transform Infra-Red (FTIR) and Gas Chromatography-Mass Spectrometer (GC-MS). The results indicate the presence of hydrocarbons, aromatics, phenols, organic acids, ketones, and aldehyde in the pyrolytic oil from HTS and HTS-WP. The acid is mainly 9-octadecenoic acid. The co-pyrolysis influenced the pyrolytic oil composition by reducing the acid from 53% when the biomass alone was pyrolysed to 32%, for co-pyrolysis of HTS-WP, while the hydrocarbons significantly increased from 1.8% to 16%. This indicates that the co-pyrolysis is effective in upgrading the biofuel from the pyrolysis of biomass, specifically, Hyphaene thebaica shell. The resulting pyrolytic oil from co-pyrolysis demonstrates that co-pyrolysis effectively enhances fuel quality relative to biomass-only. © 2025 RJEES. All rights reserved. Keywords: Co-pyrolysis, Devolatization Hyphaene thebaica shell Pyrolytic oil Waste plastics 1. INTRODUCTION The bio-oil derived from direct pyrolysis of biomass is characterized by chemicals that could not be used for specific application due to low heating value, polymerizes slowly, and not soluble in mineral 528 H.I. Mohammed et al. / Nigerian Research Journal of Engineering and Environmental Sciences 10(2) 2025 pp. 527-534 oils (Dawes et al., 2015). The global energy policy promotes net-zero carbon emissions by 2050. Currently, there is a significant gap between deployment and target. The inability of direct pyrolysis of biomass to produce high-value bio-oil for specific uses provoked research to improve bio-oil quality to enable specific applications. Among the steps taken to achieve bio-oil development is feedstock modification. Co-pyrolysis and biomass pre-treatment (chemical and thermal pre-treatment) have significantly improved bio-oil quality. However, concerns about the potential scarcity of the multiple components in co-pyrolysis, as well as the cost and environmental concerns of chemical and thermal pre-treatments, necessitate further research into abundant waste materials that can produce high-grade bio-oil for energy and chemical applications In an effort to increase the quality of the bio-oil, several studies have examined the effect of mixing different biomass on the yield and composition of the bio-oil (Fermanelli et al., 2020; Supramono & Edgar, 2019). Rice husk, wheat straw, and peanut shell were blended, and the results were published (Fermanelli et al., 2020). Initially, rice husk, wheat straw, and peanut shells each yielded a maximum bio-oil production of 46%, 58.6%, and 51%, respectively, at 500 °C. Further research looked into the effects of co-pyrolysing mixtures of wheat straw and peanut shell, rice husk and wheat straw, and wheat straw and peanut shell on bio-oil yields. Rice husk-wheat straw, peanut shell-rice husk, and wheat strawpeanut shell all produced 41, 43, and 46% of the bio-oil, respectively. Nevertheless, the bio-oil produced by simultaneously pyrolysing wheat straw, peanut shell, and rice husk had a 15% lower water content. In their study, Uzoejinwa et al. (2019) assessed the effects of co-pyrolysis of algae and rice husk. The maximum yield of each type of biomass was determined before the mixture of rice husk and algae was co-pyrolysed, and it was discovered to be 39.4% and 47.2%, respectively, at 500ºC. It was asserted that the production of bio-oil rises along with the amount of rice husk in the mixture. The co-pyrolysis of the algae and rice husk mixture reduces the amount of acetic and nitrogen compounds produced in the resultant bio-oil. The findings in the literature (Fermanelli et al., 2020; Uzoejinwa et al., 2019) demonstrate that rice husk is responsible for decreasing the water content of bio-oil. This is mostly due to the silica-rich rice husk ash, which absorbs water from the pyrolysis vapour. Additionally, Fadhil & Kareem (2021) presented details on the quantity and composition of bio-oil as a result of the co-pyrolysis of olive stones and date pits. At 500°C pyrolysis temperature and 20 °C/min heating rates, the yields of the bio-oil organic phase from the co-pyrolysis of the date pits and olive stones were 37.17% and 24.55%, respectively. Individual date pits and olive stones produced yields of 31% and 24.55%, respectively, when they were pyrolysed. However, compared to bio-oil derived from date pits and olive stones, which have an HHV of 30.12 MJ/kg and 28.95 MJ/kg, respectively, the biooil produced from the pyrolysis of these bioresource materials have a lower HHV of 27.20 MJ/kg. More research is required to preserve the synergistic yield while increasing the HHV of the bio-oil obtained from the co-pyrolysis of date pits and olive stones. Cao et al. (2018) investigated the effects of copyrolysis of cellulose, polysaccharides, and Sargassum fusiforme polysaccharides on the yields and composition of bio-oil. The yield of biochar was highest, while the yield of bio-oil from the pyrolysis of algal polysaccharides was the lowest. However, when algal polysaccharides and cellulose were copyrolyzed, the bio-oil yield of Enteromorpha clathrata and Sargassum fusiforme polysaccharides was raised by 34% and 29%, respectively, above the corresponding individual pyrolysed biomass. Sargassum fusiforme polysaccharides and cellulose were co-pyrolysed, and the result was an increase in furan from 17% to 39% and a decrease in the acid composition from 40% to 13%. Similar patterns were observed in the co-pyrolysis of cellulose and Enteromorpha clathrata polysaccharides. The interaction between cellulose-Sargassum fusiforme polysaccharides and cellulose-Enteromorpha clathrata polysaccharide blends during pyrolysis may have caused the decrease in acidity by converting acids to furans. The modifications in bio-oil composition provided evidence of interactions between cellulose and polysaccharides during co-pyrolysis. Oil shale, coal, and waste plastics are additional precursors used in co-pyrolysis. The prevalent plastics waste menace further justified biomass-waste plastics co-pyrolysis. Pinto et al. (2015) investigated the co-pyrolysis of rice husk and polyethylene. Obviously, subsequent processing enhances the bio-oil recovery and improved bio-oil fuel value. However, the study did not compare the 529 H.I. Mohammed et al. / Nigerian Research Journal of Engineering and Environmental Sciences 10(2) 2025 pp. 527-534 bio-oil obtained by co-pyrolysing polythene and rice husk to the bio-oil derived from just rice husk. There was no noticeable difference between the liquid yields from the co-pyrolysis of pine and the pyrolysis of pine alone, according to a study published in the literature (Paradela et al., 2009). However, it was observed that the quantity of gas and solids increased in tandem with the percentage of pine biomass. It has been noted that when the amount of pine grows, the heating value of gas falls due to the increased creation of CO2 and CO. While alkene yield is unaffected by biomass fraction, more alkanes are generated when the biomass proportion is between 30 and 70%. Pinto et al. (2019) studied the copyrolysis of miscanthus-, corncob-, and eucalyptus-polyethylene. As the polyethylene proportion increases, the yield of bio-oil increases. With 75% polyethylene composition, the liquid yield at 430ºC ranged from 72% to 82%, with the majority of the composition being linear alkanes and alkenes. Supramono & Lusiani, (2016) reported that when high density polyethylene (HDPE), and corn cob were co-pyrolysed, the bio-oil production increased as the proportion of HDPE increased. Additionally, copyrolysis of a sugar cane bagasse-HDPE blend was documented in the literature (Hassan et al., 2020), with the conclusion that the blend of SCB and HDPE produced more bio-oil than either material pyrolysed alone. The bio-oil had a calorific value of 42.41 MJ/kg at 600°C, a sugar cane bagasse to HDPE ratio of 40:60, and was high in alcohol, hydrocarbons, and aromatics. Similar studies looked at how co-pyrolyzing polypropylene and corn stover affected the by-products of pyrolysis. The production of bio-oil improves as polypropylene use increases. Maize stover alone produces 19.1% of bio-oil, while in a 1:1 ratio, at 550 ºC, with a greater concentration of hydrocarbons, the production was 41.8% (Wu et al., 2020). The findings of various research (Pinto et al., 2019; Supramono & Lusiani, 2016; Wu et al., 2020) all support the same trend: plastics increase liquid yields and the energy densities of gaseous and liquid products. Perhaps the simultaneous pyrolysis of biomass mixtures and plastics boosted the concentration of hydrocarbons, improving energy density. Co-pyrolysis of biomass and HDPE has positive synergistic effects on product yield, hydrocarbon compositions, and reduction of energy consumption during pyrolysis (Chin et al., 2014; Liew et al., 2021). Recently, pyrolysis of Hyphaene thebaica shell was conducted, the bio-oil and composition shows opportunity for improvement (Mohammed et al., 2024). The bio-oil hydrocarbon composition can be boosted via co-pyrolysis with waste plastics. This study focuses on evaluation of the chemical compositions of bio-oil from co-pyrolysis of Hyphaene thebaica shell-waste plastics composite. 2. MATERIALS AND METHODS 2.1. Acquisition and Preparation of Hyphaene thebaica Shell The mesocarp of the doum palm fruit was scraped and sold out in powder form. This generates the hardshell endocarp (woody shell) and endosperm (seed), which are inedible as waste. The endocarp and endosperm were cracked and separated. The woody shell was dried, crushed, and sieved, and the HTS powder that passes through a 300 micron mesh was recovered and dried in an oven for 6 hours at 110 oC. The oven-dried powder was mixed with crushed waste bottle water plastics in the ratio of 1:1 and stored in an airtight container for thermogravimetric analysis and co-pyrolysis experiments. 2.2. Thermogravimetric Analysis of Hyphaene thebaica Shell-Waste Plastics Composite In this study, a thermogravimetric analyser, TGA 50 (Shimadzu) was used for the analysis. Inside the analyser furnace, a microbalance was set up with an HTS-weighted sample (approximately 10 mg) inside an aluminium crucible. A thermocouple that was directly attached to the crucible and placed close to the sample allowed for temperature measurement. The furnace was heated under an inert atmosphere created by N2 supplied at a flow rate of 50 mL/min and a temperature ramping from 30-700 °C at 10 °C/min. Pyris Software, a proprietary thermal software developed by PerkinElmer, controlled the thermogravimetric analyser’s operations. The data acquired by the software was shown as weight loss profiles and derivative weight loss in terms of temperature. 530 H.I. Mohammed et al. / Nigerian Research Journal of Engineering and Environmental Sciences 10(2) 2025 pp. 527-534 2.3. Co-pyrolysis of Hyphaene thebaica Shell-Waste Plastics The pyrolysis of the pure biomass, doum palm shell, was first conducted and the pyrolytic was obtained. Thereafter, the co-pyrolysis of Hyphaene thebaica shell-waste plastics composite was conducted in a vertical electric furnace locally fabricated, using heating elements, capable of reaching temperatures as high as 1300 ºC. The reactor is cylindrical, 300 mm height, and 20 mm diameter, made of stainless steel equipped with a K-type thermocouple connected to Omron controller for monitoring and control of temperature. The reactor was fed with 30 grams of HTS powder, and the furnace was heated electrically at the rate of 2 °C/s to 500 °C, in nitrogen gas environment for period when no significant amount of non-condensable gas was observed. The pyrolysis vapor was condensed by passing through a condenser connected to a chiller at ice condition. The experiment was repeated for Hyphaene thebaica shell-waste plastics composites (HTS-WP). 2.4. Bio-oil Characterization The bio-oil derived from co-pyrolysis of Hyphaene thebaica shell were characterized using FTIR and methods reported in (Kabir et al., 2022). A Perkin Elmer infrared spectrometer was used to conduct FTIR spectroscopy studies on the HTS and HTS-WP pyrolytic oil functional groups and bond structure. The oils were subjected to FTIR to produce a spectrum with distinct peaks. With a step size of 4 cm-1 and a scanning rate of 40, scanning was performed in a band between 4000-400 cm-1. The spectrometer displayed an absorption spectrum with peaks corresponding to particular kinds of functional groups and bonds because the HTS and HTS-WP pyrolytic oils absorbed infrared radiation from various bands. The absorption bands of the functional groups were matched with the catalogued spectra of known materials using an inbuilt reference library program installed in a computer database system. Then, the functional groups were identified in terms of spectrum peaks. The chemical composition of bio-oil was determined using a gas chromatograph-mass spectrometer (GCMS) system, Agilent 8890 GC and 5977 MSD equipped with NIST-EPA_NIH-2014 library. The biooil sample was dissolved in acetone at 1:10 ratio and centrifuged before analysis. The quantity of each compound was determined by comparing the retention time and mass spectral data with standards from NIST mass spectral library installed in a computer database system connected to the GC. Quantification was completed by built-in data-handling software supplied by the manufacturer of the gas chromatograph. The results (composition) were reported as a relative percentage of the total peak area. 3. RESULTS AND DISCUSSION 3.1. Thermogravimetric Decomposition Behaviour of the Composite The results of thermogravimetric analysis of Hyphaene thebaica shell-Waste plastics using thermogravimetric (TG) and derivative thermogravimetric (DTG) curves derived from thermogravimetric data is presented in Figure 1. It shows the decomposition profile of the HTS-WP in nitrogen gas environment. Figure 1: TG and DG curves of Hyphaene thebaica shell devolatilisation 531 H.I. Mohammed et al. / Nigerian Research Journal of Engineering and Environmental Sciences 10(2) 2025 pp. 527-534 The results of thermogravimetry with temperature ramping suggested that HTS-WP degrade in stages, as reported by the previous studies (Fadhil & Kareem, 2021; Siddiqi et al., 2021). Three steps typically occur during the thermal degradation of various biomass sources. The release of moisture and lighter volatiles hosted on the HTS-WP macro-structure caused the first stage, which occurred between 40 °C and 200 °C. The drying zone, the first stage, is seen to have a minimal weight loss of 6.20 wt%. With a maximum weight loss of 60 wt%, the HTS-WP considerably degraded in the second stage between 180 ºC and 550 ºC. This is due to the total decomposition of cellulose and hemicellulose with continuous heating. The peaks observed on the DTG curves between 190 °C and 380 °C belong to the degradation of hemicelluloses, extractives and celluloses (Mohammed et al., 2022; Vyazovkin et al., 2020). The lignin-rich char residue saw a little weight loss in the last stage between 400 °C and 690 °C as a result of the breakdown of the glycosidic bonds of the lignin component of biochar. The final stage, which is typically referred to as the passive pyrolysis stage, has a total weight reduction of roughly 8.47 wt%. This is consistent with the results in the literature (Liyanage & Pieris, 2015). Finally, the biochar of 37 wt% remains at 690 °C after the degradation of the residual lignin-rich char. A total weight loss and maximum weight loss rate of 50 wt% and 4.5 wt% loss/min was recorded, respectively. 3.2. FTIR Analysis of Pyrolytic Oil Figure 2 shows FTIR spectra of bio-oils derived from pyrolysis of Hyphaene thebaica shell and o-pyrolysis of HTS-WP. The FTIR shows many peaks signaling the complexity of the bio-oil. The specific bands from FTIR spectroscopy related to the functional groups and fingerprint structure are presented in Table 1. The peaks at 1513.3, 1410–1310, 1267.3 and 1021 cm-1 for both bio-oil derived from pyrolysis and co-pyrolysis process indicate C-H bending vibration, Phenol or tertiary alcohol OH bend, Aromatic ether or aryl -O stretch, Primary amine, C-N stretch, respectively. The similarity in bio-oil functional groups and fingerprints suggests no alteration of the themochemical pathways of devolatilisation of HTS due to the presence of waste plastics. Figure 2: FTIR of pyrolytic oils from Hyphaene thebaica shell-waste plastics It can be observed that the peaks recorded are similar for the pyrolysis of HTS and the co-pyrolysis of HTSWP. The bands primarily contain functional groups for alcohol (3570–3200 cm-1), carbonyl compounds such as esters, carboxylic acids (1725–1700), aromatics (1615–1580), alkane, and alkene (Asadieraghi & Daud, 2015; Gibril et al., 2020). The peaks of the FTIR results show the presence of a bonded hydroxyl group for the pyrolysis and co-pyrolysis process, suggesting the abundance of alcohol and phenols. 3.3. Chromatographic Composition of Pyrolytic Oil The compositions of bio-oil from pyrolysis and co-pyrolysis of HTS and HTS-WP were analysed using GC/MS. The bio-oils of HTS samples were mainly composed of unsaturated acids, about 50%, with Octadecenoic acids the dominant compounds, 45%; however, esters, phenols, aldehydes, ketones, ethers, aromatics, and hydrocarbons were also present. The chromatographic composition is classified based on functional groups ids presented in Figure 3. It is well known that these compounds are the major products 532 H.I. Mohammed et al. / Nigerian Research Journal of Engineering and Environmental Sciences 10(2) 2025 pp. 527-534 from pyrolysis of lignocellulosic biomass (Ahmad et al., 2014; Palamanit et al., 2019). which are derived from the cleavage of the ether bonds between the cellulose, hemicellulose and lignin building units (Den et al., 2018). In comparison with thermal pyrolysis, co-pyrolysis alters the composition of the bio-oils. The copyrolysis reduces the composition of the acids and increase the ester yields from 5 to 31%. There is slight increase of alcohols yield from 10 to 12%, while there is slight decrease in benzene derivative compounds, and formation of aldehyde and ketones. The other compounds such as ether, furan and furfural have decreased. This might be due to cracking and hydrodeoxygenation of pyrolysis vapour facilitated by the secondary reactions due to radicals generated from the plastics decomposition. The phenolic compounds dominated by complex. The cleavage of the macrostructure molecule is evidence of contribution of radicals generations that react with macromolecules to break it down to smaller molecules of importance. Table 1: Peaks of FTIR spectra of the pyrolytic oil S/No. Pyrolytic oil from HTS Pyrolytic oil from HTS-WP composites Peaks Functional groups Peaks Functional groups 1 3369.5 OH, H-bonded O-H stretch, polymeric 3384.4 OH, H-bonded O-H stretch, polymeric 2 3000 C-H stretch 3 2087.3 aromatics ring 2929.7 Methylene C-H asym./sym. Stretch 4 1707.1 carbonyls (carboxylic acid,ketone, aldehyde) 1699.7 conjugated ketone 5 1640 double bond, C=C from aromatic compound 1595.3 Secondary amine, >N-H bend 6 1513.3 C-H bending vibration 1513.3 C-H bending vibration 7 1386.6 Phenol or tertiary alcohol, OH bend 1371.6 Phenol or tertiary alcohol, OH bend 8 1267.3 Aromatic ethers, aryl -O stretch 1222.6 Phenol, C-O stretch 9 1221.3 Phenol, C-O stretch 10 Alkyl-substituted ether, C-O stretch/cyclohexane ring vibration 1021 Alkyl-substituted ether, C-O stretch/cyclohexane ring vibration 11 693.3 Alcohol, OH out-of-plane bend C-H 1,2-Disubstitution (ortho, C-H Monosubstitution (phenyl) Figure 3: Sub-group of composition pyrolytic oil of Hyphaene thebaica shell 533 H.I. Mohammed et al. / Nigerian Research Journal of Engineering and Environmental Sciences 10(2) 2025 pp. 527-534 4. CONCLUSION The co-pyrolysis of Hyphaene thebaica shell with waste plastics (HTS-WP) was conducted to evaluate the pyrolytic oil compositions. The TGA results indicates that HTS-WP high volatile matters 63%, responsive to thermal degradation to generate volatiles between 200 and 400 °C establishing the viability of copyrolysis of Hyphaene thebaica shell-waste plastic (HTS-WP) to produce pyrolytic oil. The co-pyrolysis of the HTS-WP yielded bio-oil with improved hydrocarbon composition from 2%to 16%. The acids composition was reduced to 32% from 53% compared to when HTS alone was pyrolysed. 5. ACKNOWLEDGMENT The authors wish to acknowledge the assistance and contributions of the laboratory staff of the Department of Chemical Engineering, University of Maiduguri, in conducting the pyrolysis experiments. 6. CONFLICT OF INTEREST There is no conflict of interest associated with this work. REFERENCES Ahmad, R., Hamidin, N., Ali, U. F. M., and Abidin, C. Z. A. (2014). Characterization of bio-oil from palm kernel shell pyrolysis. Journal of Mechanical Engineering and Sciences, 7(1), pp.1134–1140. https://doi.org/10.15282/jmes.7.2014.12.0110 Asadieraghi, M., and Daud, W. M. A. W. (2015). In-depth investigation on thermochemical characteristics of palm oil biomasses as potential biofuel sources. Journal of Analytical and Applied Pyrolysis, 115, pp.379–391. https://doi.org/10.1016/j.jaap.2015.08.017 Cao, B., Xia, Z., Wang, S., Abomohra, A. E., Cai, N., Hu, Y., Yuan, C., Qian, L., Liu, L., Liu, X., Li, B., He, Z., and Wang, Q. (2018). Journal of Analytical and Applied Pyrolysis A study on catalytic co-pyrolysis of cellulose with seaweeds polysaccharides over ZSM-5 : Towards high-quality biofuel production. Journal of Analytical and Applied Pyrolysis, 134(July), pp.526–535. https://doi.org/10.1016/j.jaap.2018.07.020 Chin, B. L. F., Yusup, S., Al Shoaibi, A., Kannan, P., Srinivasakannan, C., and Sulaiman, S. A. (2014). Kinetic studies of co-pyrolysis of rubber seed shell with high density polyethylene. Energy Conversion and Management, 87, pp.746–753. https://doi.org/10.1016/j.enconman.2014.07.043 Dawes, G. J. S., Scott, E. L., Nôtre, J. Le, Sanders, J. P. M., and Bitter, J. H. (2015). Decarboxylation and Decarbonylation – a review. Green Chemistry, 2015(17), pp.3231–3250. https://doi.org/10.1039/c5gc00023h Den, W., Sharma, V. K., Lee, M., and Nadadur, G. (2018). Lignocellulosic Biomass Transformations via Greener Oxidative Pretreatment Processes : Access to Energy and Value-Added Chemicals. Frontiers in Chemistry, 6(141),pp. 1–23. https://doi.org/10.3389/fchem.2018.00141 Fadhil, A. B., and Kareem, B. A. (2021). Co-pyrolysis of mixed date pits and olive stones: Identification of bio-oil and the production of activated carbon from bio-char. Journal of Analytical and Applied Pyrolysis, 158(June), 105249. https://doi.org/10.1016/j.jaap.2021.105249 Fermanelli, C. S., Córdoba, A., Pierella, L. B., & Saux, C. (2020). Pyrolysis and copyrolysis of three lignocellulosic biomass residues from the agro-food industry : A comparative study. Waste Management, 102, pp.362–370. https://doi.org/10.1016/j.wasman.2019.10.057 Gibril, M. E., Zhang, N., Yi, Y., Liu, P., Wang, S., Tesfaye, T., and Kong, F. (2020). Physicochemical characterization and future bene fi ciation routes of wild fruit waste ( Hyphaene Thebaica seed ) as a source to extract mannan. Journal of Cleaner Production, 267, 121949. https://doi.org/10.1016/j.jclepro.2020.121949 Hassan, H., Hameed, B. H., and Lim, J. K. (2020). Co-pyrolysis of sugarcane bagasse and waste high-density polyethylene: Synergistic effect and product distributions. Energy, 191, 116545. https://doi.org/10.1016/j.energy.2019.116545 Kabir, G., Mohammed, I. Y., Abakr, Y. A., and Hameed, B. H. (2022). Intermediate Pyrolysis of Desert Date Shell for Conversion to High-Quality Biomaterial Resources. Chemical Engineering and Technology, 00, pp.1–11. https://doi.org/10.1002/ceat.202200095 Liew, J. X., Loy, A. C. M., Chin, B. L. F., AlNouss, A., Shahbaz, M., Al-Ansari, T., Govindan, R., and Chai, Y. H. (2021). Synergistic effects of catalytic co-pyrolysis of corn cob and HDPE waste mixtures using weight average global process model. Renewable Energy, 170, pp.948–963. https://doi.org/10.1016/j.renene.2021.02.053 Liyanage, C. D., and Pieris, M. (2015). A Physico-Chemical Analysis of Coconut Shell Powder. Procedia Chemistry, 16, pp.222–228. https://doi.org/10.1016/j.proche.2015.12.045 534 H.I. Mohammed et al. / Nigerian Research Journal of Engineering and Environmental Sciences 10(2) 2025 pp. 527-534 Mohammed, H. I., Garba, K., Ahmed, S. I., & Abubakar, L. G. (2022). Thermodynamics and kinetics of Doum ( Hyphaene thebaica ) shell using thermogravimetric analysis : A study on pyrolysis pathway to produce bioenergy. Renewable Energy, 200(October), pp.1275–1285. https://doi.org/10.1016/j.renene.2022.10.042 Mohammed, I. H., Garba, K., Ahmed, S. I., and Abubakar, L. G. (2024). Pyrolysis of hyphaene thebaica shell over ceramic tile dust-derived catalysts and assessment of the produced bio-oil. Waste Management Bulletin, 2(4), pp.64– 75. https://doi.org/10.1016/j.wmb.2024.08.009 Palamanit, A., Khongphakdi, P., Tirawanichakul, Y., and Phusunti, N. (2019). Investigation of yields and qualities of pyrolysis products obtained from oil palm biomass using an agitated bed pyrolysis reactor. Biofuel Research Journal, 6(4), pp.1065–1079. https://doi.org/10.18331/BRJ2019.6.4.3 Paradela, F., Pinto, F., Gulyurtlu, I., Cabrita, I., and Lapa, N. (2009). Study of the co-pyrolysis of biomass and plastic wastes. Clean Technologies and Environmental Policy, 11(1), pp.115–122. https://doi.org/10.1007/s10098-008-01761 Pinto, F., Duarte, L. C., Carvalheiro, F., Paradela, F., Costa, P., Marques, J., André, R., Marques, P., Costa, D., and Sampaio, B. (2019). Production of liquid compounds by co-pyrolysis of different pre-treated biomasses mixed with plastic wastes. Chemical Engineering Transactions, 76(2015), pp.1393–1398. https://doi.org/10.3303/CET1976233 Pinto, F., Miranda, M., and Costa, P. (2015). Co-pyrolysis of wastes mixtures obtained from rice production. Upgrading of produced liquids. Chemical Engineering Transactions, 43, pp.2053–2058. https://doi.org/10.3303/CET1543343 Siddiqi, H., Biswas, S., Kumari, U., Hima Bindu, V. N. V., Mukherjee, S., and Meikap, B. C. (2021). A comprehensive insight into devolatilization thermo-kinetics for an agricultural residue: Towards a cleaner and sustainable energy. Journal of Cleaner Production, 310, 127365. https://doi.org/10.1016/j.jclepro.2021.127365 Supramono, D., and Edgar, J. (2019). Characteristics of Non-Polar Bio-oil Produced by Co-pyrolysis of Corn Cobs and Polypropylene using CO _ 2 as Carrier Gas Characteristics of Non-Polar Bio-oil Produced by Co-pyrolysis of Corn Cobs and Polypropylene using CO 2 as Carrier Gas.IOP Conf Ser Mater Sci Eng. doi:10.1088/1757899X/162/1/ 01201 6(1), pp.78–84. Supramono, D., and Lusiani, S. (2016). Improvement of bio-oil yield and quality in co-pyrolysis of corncobs and high density polyethylene in a fixed bed reactor at low heating rate. IOP Conference Series: Materials Science and Engineering, 162(1). https://doi.org/10.1088/1757-899X/162/1/012011 Uzoejinwa, B. B., He, X., Wang, S., Abomohra, A. E., Hu, Y., He, Z., and Wang, Q. (2019). Co-pyrolysis of macroalgae and lignocellulosic biomass parameters on yields. Journal of Thermal Analysis and Calorimetry, 136(5), pp.2001–2016. https://doi.org/10.1007/s10973-018-7834-2 Vyazovkin, S., Burnham, A. K., Favergeon, L., Koga, N., Moukhina, E., Pérez-maqueda, L. A., and Sbirrazzuoli, N. (2020). Thermochimica Acta ICTAC Kinetics Committee recommendations for analysis of multi-step kinetics. Thermochimica Acta, 689(March), 178597. https://doi.org/10.1016/j.tca.2020.178597 Wu, F., Ben, H., Yang, Y., Jia, H., Wang, R., and Han, G. (2020). Effects of different conditions on co-pyrolysis behavior of corn stover and polypropylene. Polymers, 12(4), pp.1-14. https://doi.org/10.3390/POLYM12040973.