Optimization of flexural properties and thermal conductivity of Washingtonia plant biomass waste biochar reinforced bio-mortar

Abstract

The building industry's current trend to reduce and protect environmental impact implies the design and fabrication of more ecological and sustainable building materials. Biochar has the potential to be incorporated in construction materials for its specific characteristics and environmental advantaaffnciges that it offers. Plasters are susceptible to cracking and spalling due to environmental conditions. This study offers the development of a novel bio-mortar biochar-reinforced plaster products obtained by pyrolysis of Washingtonia plant biomass biochar (WPBB). Three biochar contents (1, 2 and 3%) according to three temperatures (300, 400 and 500 °C) were examined. Sample characterization, such as FTIR (Fourier Transform Infrared Spectroscopy) and SEM (Scanning Electron Microscopy), was conducted to investigate bio-mortars obtained from biomass waste biochar. The incorporation of WPBB led to increased bending strength and decreased ductility compared to reference data of plaster biocomposite i.e.: 229%, 200% respectively, for the reinforced plaster with an optimum content of 1 w% pyrolyzed biochar at 500 °C. However, it was found that the use of less than 2 wt% biochar could give plaster biocomposites superior performance to conventional materials and the 2% biochar content improved the ductility compared to the 1% and 3% contents.; Adding biochar to mortar improved thermal performance compared to the reference mixture, allowing its use as a material for moisture control. Furthermore, the models generated using RSM response surface methodology and ANN neural networks agreed well with those obtained experimentally for the bending properties the newly conceived plaster/biochar biocomposite. Gypsum bio-mortars containing WPBB can be utilized to create lightweight mortars with exceptional qualities including low density and thermal insulation.

Keywords

• Washingtonia waste biochar
• Reinforced plaster
• Thermal conductivity
• Optimization/ prediction model
• Mathematical model