Optimization via response surface methodology of palm kernel shell biochar for supplementary cementitious replacement.

The use of sustainable materials in the construction industry has been on the rise recently. Studies have proven that the use of conventional concrete and its raw materials has a negative impact on the environment. Research on incorporating biochar as a supplementary cementitious material has been recently evolving and has shown that the attributes of biochar are highly affected by the pyrolysis parameters. These attributes have enhanced the properties of biochar concrete and mortar composite. This paper identifies the different physiochemical properties exhibited by palm kernel shell biochar through optimization by response surface methodology. Focusing on some of the properties of biochar that have proven beneficial when used as a cement replacement. Very limited research has used optimization tools for the production of biochar with the intention of using it as a cement substitute. Pyrolysis was conducted by a tubular furnace at different temperature ranges from 200 °C to 800 °C. The biomass and biochar have been analyzed with TGA and FESEM-EDX. The targeted biochar properties and selected responses are the yield, carbon, oxygen, silica, and potassium content. The optimized parameters obtained are 409 °C, 15 °C/min, 120 min with responses of 38.2% yield, 73.37% carbon, 25.48% oxygen, 0.39% potassium and 0.44% silica. Thermal properties of the palm kernel shell biochar affected by the pyrolysis factors such as temperature, heating rate and residence time have also been discussed. In conclusion, this study supports and encourages the use of palm waste, which is abundant in Malaysia, as a supplementary cementitious material to promote sustainable growth in construction. [Display omitted] • Hypothesis for a high potential of palm kernel shell biochar to be used as supplementary cementitious replacement. • The factors that are taken into consideration are pyrolysis temperature, heating rate and residence. The responses are biochar yield, carbon, oxygen, potassium, and silica content. • Optimized round of palm kernel shell biochar is 409 °C, 15 °C/min and 120 min. • The carbon content of the biochar is directly proportional to the pyrolysis temperature. • The pyrolysis temperature and residence time are more effective than heating rate on the physiochemical properties. [ABSTRACT FROM AUTHOR]