A review on the application of biopolymers (xanthan, agar and guar) for sustainable improvement of soil

Abstract

AbstractThis review explores the use of biopolymers as sustainable alternatives for soil improvement in geotechnical engineering. Specifically, focusing on three commonly used biopolymers: xanthan gum, agar gum, and guar gum, this review highlights their potential applications and effects on the geotechnical properties of different soil types. Xanthan gum exhibits improved impermeability and water storage capacity, making it suitable for anti-wind erosion, soil remediation, and grouting vegetation growth. Agar gum shows promise in liquefaction remediation with its gelation process and absence of chemical reactions during soil cementation. It is resistant to thermal degradation, oxidation, acid-alkaline environments, and salt concentrations. Its hygroscopicity and stability make it useful for soil stabilization. Guar gum enhances shear strength, reduces permeability, and improves soil stability, making it effective for mine tailing stabilisation, slope stability, and other geotechnical applications. Being a polymeric molecule, as it breaks down, it becomes more biopolymer-rich, making it more resistant to wetting and drying processes. This review discusses biopolymer-treated soils’ strengthening mechanisms, such as hydrogel formation and cross-links between soil particles. The utilisation of biopolymers offers advantages in terms of abundance, non-toxicity, and potential for reducing greenhouse gas emissions. The review also identifies the use of biopolymers in mine tailings. Although further research is needed to optimise their application and explore their full potential in sustainable improvement practices, This integration of biopolymers in soil engineering would provide a more environmentally friendly approach.