Optimization of Celery Tail Waste-Based Hydrogels and Application in Soil Water Retention

In order to meet the demand for coordinated development of agricultural waste utilization and water-saving agriculture, this study utilized waste celery tailings (CT) to make a super-absorbent hydrogel by chemical cross-linking. The hydrogel was optimized and screened. The study demonstrated the optimal CT-gel synthesis method: 7.5 wt% CT, 0.05 wt% MBA cross-linker, and 70 °C for 2 h. The optimized gel had a water absorption of 708 g/g and a water retention of more than 20% at 25 °C on day 10. The soil water retention of the CT-gel increased with time and dosage. In sandy soils, 0.6% CT-gel was most effective. The pot experiment showed that 2% of the gel significantly increased the height and growth rate of radish seedlings. This study effectively utilized various components of CT and provided a scalable approach for converting agricultural waste into functional materials, which is valuable for arid soil improvement and sustainable agriculture.