Multifunctional porous hydrogel with nutrient controlled-release and excellent biodegradation

Water resource shortage, low fertilizer use efficiency, and environmental degradation are major challenges confronted by global agriculture and threatens the ecological environment, while there remains little research on achieving a combination of sustained nutrient release and pollution impact assessment. Taking biomass waste collagen (leather waste) as a tailor-made intrinsic nitrogen resource, we prepared a cost-effective and ecofriendly biodegradable protein-based hydrogel with the ability of nutrient controlled-release and heavy metal adsorption. Specifically, the as-prepared biofertilizer exhibited good biodegradability in soil, which can be a carbon source for supporting the growth of Ensifer sp.Y1. Furthermore, the as-prepared biofertilizer shows a high water absorbency capacity of 2208 g g(-1), as well as preferable controlled-release nitrogen and potassium fertilizer for more than 40 days. Meanwhile, the multifunction of hydrogel was evaluated simultaneously for heavy metal adsorption in simulating contaminated by Cr (III) under all kinds of environmental parameters, and the hydrogel exhibited excellent adsorption capacity of 149.3 g g(-1) for Cr (III). Therefore, this easy and efficient process opens up a new avenue to develop integrated output-increasing techniques through a circular economy for soil pollution control and wastewater treatment.

Automated summary

The study developed a protein-based hydrogel that can achieve sustained nutrient release and heavy metal adsorption, serving as an eco-friendly biofertilizer with good biodegradability and growth support in soil.