Starch-based hydrogel powder for enhanced dust suppression

Abstract

Air pollution from fugitive dust poses a significant health risk to population in arid regions. Conventional chloride-based suppressants offer temporary dust control, leading to soil contamination and infrastructure corrosion. This study proposes the synthesis of a starch-based powder that regenerates into hydrogel for dust mitigation, owing to its agglomeration and crust-forming abilities. The hydrogel was synthesized by thermally degrading amylopectin-rich starch, undergoing a freeze-thaw cycle, and pulverizing into powder. The powder was then added to hot water (>65 °C) at concentrations of 0.5 %, 1 %, 2 %, and 3 % by weight of solution to form regenerated amylopectin starch hydrogel (RASH). Dust suppression performance was evaluated using PI-SWERL (Portable in-situ Wind Erosion Lab) to assess wind erosion rates, and penetration tests to measure crust strength. Results demonstrated that 1 %wt. RASH achieved a 100 % reduction in wind erosion rates, even at speed of 90 km/h. This is attributed to the agglomeration of soil grains and formation of thick crust. Field tests over 20 days confirmed sustained PM10 suppression in extreme arid conditions (39°C) across various soil types. As a result, a novel, energy-efficient starch-based dust suppressant is proposed, offering a low-cost and scalable solution for long-term dust control in arid climates.