Abdul-Rahman, A., Sulaiman, F. and Abdullah, N. (2016). Influence of Washing Medium Pre-treatment on Pyrolysis Yields and Product Characteristics of Palm Kernel Shell. Journal of Physical Science. 27(1), 53–75.

Barnakova, N. C., Khokhlovaa, G. P., Malyshevaa, V. Y., Popovaa, A. N. and Ismagilova, Z. R. (2015). X_Ray Diffraction Analysis of the Crystal Structures of Different Graphite. Solid Fuel Chemistry. 49(1).,25–29.

Bogeat, B. A. (2019): Understanding and Tuning the Electrical Conductivity of Activated Carbon: A State-of-the-Art Review, Critical Reviews in Solid State and Materials Sciences. DOI: 10.1080/10408436.2019.1671800

Chowdhury Z. Z., Karim, Z. M., Ashraf, A. M.and Khalid K. (2016). Influence of carbonization temperature on physicochemical properties of biochar derive from slow pyrolysis of Durian wood (Durio zibethinus) sawdust. Bioresources .11(2),3356-3372.

Coates, J., (2019). Interpretation of Infrared Spectra, A Practical Approach, Encyclopedia of Analytical Chemistry. Copyrights John Wiley & Sons Ltd.1-23.

Daud, W. M. A. W., Ali, W. S. W. and Sulaiman, Z. M. (2001). Effect of carbonization temperature on the yield and porosity of char produced from palm shell. Journal of chemical technology and biotechnology. 76.1281-1285. Doi:10.1002/jctb.515

Dehkhoda, M. A. (2016). Development and characterization of activated biochar as electrode material for capacitive deionization. PhD dissertation (published) Chemical and Biological Engineering, University of British-Columbia, Vancouver.

Ding, Y., Wang, T., Dong, D. and Zhang, Y. (2020). Using biochar and coal as the electrode material for Super capacitor applications. Frontier Energy Research. 7:159. Doi:10.3389/fenrg.2019.00159

Fernandes, C. C. B., Mendes, F. K., Júnior, D. F. A., Caldeira, S. P. V., Teófilo, S. M. T, Silva, S. T., Mendonça, V., Souza, F. M. and Silva, V. D. (2020). Impact of Pyrolysis Temperature on the Properties of Eucalyptus Wood-Derived Biochar. Materials. 13, 5841.doi:10.3390/ma13245841

Ghali A. E., Marzoug, I. B., Baouab, M. H. V. and Roudesli, M. S. (2012). “Separation and characterization of new cellulosic fibres from the Juncus acutus plant”. Bioresource.7(2). 2002-2018.

Ghani, W. A.W. K., Fernandez, S. P., Halele, Q. M., Sobri, S. and Jasni, J. (2016). Physical and Electrochemical Characterization of Palm Kernel Shell Biochar (PKSB) as Supercapacitor. MATEC Web of Conferences 62. DOI: 10.1051/matecconf/2016620

Girgis, S. B., Temerk, M. Y., Gadelrab, M. M. and Abdullah, D. I. (2007). X-ray Diffraction Patterns of Activated Carbons Prepared under Various Conditions. Carbon Science. 8(2). 95-100.

Hoffmann, V., Rodriguez, C. C., Sautter, D., Maringolo, E. and Kruse, A. (2019). Study of the electrical conductivity of biobased carbonaceous powder materials under moderate pressure for the application as electrode materials in energy storage technologies. GCB Bioenergy. 11:230–248.

Huggins, T., Wanga, H., Kearns, J., Jenkins, P. and Ren, J. Z. (2014). Biochar as a sustainable electrode material for electricity production in microbial fuel cells. GCB Bioenergy.11:230–248. https://doi.org/10.1111/gcbb.12545

Imam, T and Capareda, S (2012). Characterization of bio-oil, syn-gas and bio-char from switchgrass pyrolysis at various temperatures. J. Anal. Appl. Pyrol., 93: 170-177.

Kang, S. D., Lee, M. S., Lee, H. S. and Roh, S. J. (2018). X-ray diffraction analysis of the crystallinity of phenolic resinderived carbon as a function of the heating rate during the carbonization process. Carbon Letters.. 27.108-111.

Kong, S. H., Loh, K. S., Bachmann, T. R., Zainal, H. and Cheong, Y. K. (2019). Palm kernel shell biochar Production,characteristics and carbon sequestration potential. Journal of Oil Palm Research. DOI:https://doi.org/10.21894/jopr.2019.0041

Kwon, H. J., Park, B. S., Ayrilmis, N., Oh, W. S. and Kim, H. N. (2013). Effect of carbonization temperature on electrical resistivity and physical properties of wood and wood-based composites. Composites: Part B 46, 102–107. http://dx.doi.org/10.1016/j.compositesb.2012.10.012

Lee, L. C., H'ng, S. P., Paridah, T., Chin, L. K., Khoo, S. P., Nazrin, R. A. R., Asyikin, N. S. and Maminski, M. (2017). Effect of Reaction Time and Temperature on the Properties of Carbon Black Made from Palm Kernel and Coconut Shell. Asian journal of scientific research. 10 (10). 24-33.

Liu, Y., He, Z and Uchimiya, M. (2015). Comparison of Biochar Formation from Various Agricultural By-Products Using FTIR Spectroscopy. Modern Applied Science. 9(4). www.ccsenet.org/mas

Liyanage D. C. and Pieris, M. (2015). A physico-chemical analysis of coconut shell powder. Procedia chemistry. 16. 222-228. www.sciencedirect.com.

Ma, X., Yuan, C. and Liu, X. (2014). Mechanical, Microstructure and Surface Characterizations of Carbon Fibers Prepared from Cellulose after Liquefying and Curing. Materials 7. 75-84; doi:10.3390/ma7010075

Ma, Z., Yang, Y., Ma, Q. Zhou, H., Luo, X., Liu, X. and Wang, S. (2017). Evolution of the chemical composition, functional group, pore structure and crystallographic structure of bio-char from palm kernel shell pyrolysis under different temperatures. Journal of Analytical and Applied Pyrolysis. http://dx.doi.org/10.1016/j.jaap.2017.07.015

Mochidzuki, K., Soutric, F., Tadokoro, K., Antal, J. M., Toth, M., Zelei, B. and Varhegyi, G. (2003). Electrical and Physical Properties of Carbonized Charcoals. Ind. Eng. Chem. Res. 42, 5140-5151.

Nanda, S., Dalai, K. A., Berruti, F. and Kozinski, A. J. (2015). Biochar as an Exceptional Bioresource for Energy, Agronomy, Carbon Sequestration, Activated Carbon and Specialty Materials. Waste Biomass Valor. DOI 10.1007/s12649-015-9459-z

Nandiyanto, A. B. D., Oktiani, R. and Ragadhita, R. (2019). How to Read and Interpret FTIR Spectroscope of Organic Material. Journal of Science & Technology. 4(1).

Nicholas, F. A., Hussein, Z. M., Zaina, Z. and Khadiran, T. (2018). Palm Kernel Shell Activated Carbon as an Inorganic Framework for Shape-Stabilized Phase Change Material. Nanomaterials. 8, 689. doi:10.3390/nano8090689

Noh, C. H. C., Azmin, N. F. M. and Amid, A. (2017). Principal Component Analysis Application on Flavonoids Characterization. Advances in Science, Technology and Engineering Systems Journal (2) 3, 435-440.

Okolo, I. B., Oke, O. E., Agu, M. C., Adeyi, O., Nwoso-Obieogu, K. and Akatobi, N. K. (2020). Adsorption of lead(II) from aqueous solution using Africa elemi seed, mucuna shell and oyster shell as adsorbents and optimization using Box–Behnken design. Applied Water Science. 10:201. https://doi.org/10.1007/s13201-020-01242-y

Okoroigwea, E. C. and Saffron, C. M. (2012). Determination of bio-energy potential of palm kernel shell by physicochemical Characterization. Nigerian Journal of Technology (NIJOTECH) 31(3), 329–335.

Rabiu, Z. and Zakaria, A. Z. (2017). Pyrolignous Acid Production from Palm Kernel Shell Biomass. J. Appl. Environ. Biol. Sci., 7(2S). 59-62.

Rana, R., Mu¨ller, G., Naumann, A. and Polle, A. (2008). FTIR spectroscopy in combination with principal component analysis or cluster analysis as a tool to distinguish beech (Fagus sylvatica L.) trees grown at different sites. Holzforschung, 62. 530–538.

Reeves, J. (2012). Mid-infrared spectroscopy of biochars and spectral similarities to coal and kerogens: what are the implications? Appl. Spectr.. 66:689-695. http://dx.doi.org/10.1366/11-06478

Rout, T., Pradhan, D., Singh, R. K. and Kumari, N. (2016). Exhaustive study of products obtained from coconut shell Pyrolysis. J. Environ. Chem. Eng. http://dx.doi.org/10.1016/j.jece.2016.02.024.

Sanguansat, P. (ed.). (2012). Principal component analysis - engineering applications. Intech, Rijeka, Croatia

Satheesh, M., Pugazhvadivu, M., Prabu, B., Gunasegaran, V. and Manikandan, A. (2019). Synthesis and Characterization of Coconut Shell Ash. Journal of Nanoscience and Nanotechnology. 19, 4123–4128. www.aspbs.com/jnn

Štefanko, U. A. and Leszczynska, D. (2020). Impact of Biomass Source and Pyrolysis Parameters on Physicochemical Properties of Biochar Manufactured for Innovative Applications. Frontiers in Energy Research. 8(138), 1-13 doi:10.3389/fenrg.2020.00138

Stein, I.Y., Ashley L. K., Alexander J. C., Luiz A. and Brian L. W. (2017). Mesoscale Evolution of Non-Graphitizing Pyrolytic Carbon in Aligned Carbon Nanotube Carbon Matrix Nanocomposites. Journal of Materials Science 52(24),13799-13811.

Wang, P., Zhang, J., Shao, O., Wang, G. (2018). Physicochemical properties evolution of chars from palm kernel shell pyrolysis. Journal of Thermal Analysis and Calorimetry. https://doi.org/10.1007/s10973-018-7185-z(0123456789.

Yahaya, Z. A., Somalua, R. M., Muchtara, A., Sulaimanc, A. S. and Dauda, W. R. W. (2020). Effects of temperature on the chemical composition of tars produced from the gasification of coconut and palm kernel shells using downdraft fixed-bed reactor. Fuel 265. https://doi.org/10.1016/j.fuel.2019.116910

Yang, H., Yan, R., Chen, H., Lee, H. D., Liang, T. D. and Zheng, C. (2006). Mechanism of Palm Oil Waste Pyrolysis in a Packed Bed. Energy & Fuels.20, 1321-1328.

Yashim, M. M., Razali, N., Saadon, N. and Abdul Rahman, N. (2016). Effect of activation temperature on properties of activated carbon prepared from oil palm kernel shell (OPKS). ARPN Journal of Engineering and Applied Sciences.,11(10), 6389- 6392.