Comparative evaluation of a multi-functional dust suppressant synthesized from Sapindus mukorossi extract and bentonite clay

Dust suppression is a critical aspect in the management of dispersed particulate matter from industrial, mining, and vehicular traffic. This research is an effort towards realizing UN SDGs namely ‘Good Health and Wellbeing’ and ‘Sustainable Cities and Communities’ by improving air quality with effective dust control. Conventional chemical dust suppressants are often non-biodegradable and pose long-term ecological hazards. This study focuses on the comparative evaluation of a multi-functional dust suppressant from bentonite clay and Sapindus mukorossi (soapnut) extract with lignin recovered from industrial waste Kraft black liquor and its derivatives. This is novel research on utilization of soapnut extract for dust suppression. The multi-functional performance of the prepared dust suppressants was evaluated through a series of tests, including wind erosion, wetting ability, moisture retention, penetration resistance and biodegradability. The dust suppressants were characterized using X-ray Diffraction, Fourier Transform Infrared Spectroscopy, Scanning Electron Microscopy, Energy Dispersive X-ray Spectroscopy and Optical Microscopy techniques. Soapnut extract with bentonite exhibited the best overall performance, with the least wind erosion weight loss of 11.2%, penetration depth of 8.2 mm and a moisture loss of 35%. It displayed a good wetting ability of 40 min and favorable biodegradability of 0.8. The results indicate that integrating Soapnut extract with bentonite clay yields a high-performance, environmentally friendly and cost-effective alternative to conventional dust suppressants and has strong potential for dust management applications.