Engineered LDH-alginate composite hydrogel columns for selective heavy metal removal

Area of Science:

• Materials Science
• Environmental Chemistry
• Food Safety Engineering

Background:

• Heavy metal contamination in food-related wastewater presents a significant risk to public health and food safety.
• Conventional methods for heavy metal removal can be inefficient or costly.
• Development of advanced adsorbent materials is crucial for effective remediation.

Purpose of the Study:

• To develop and evaluate a novel composite hydrogel for the efficient adsorption of cationic heavy metal pollutants.
• To assess the adsorption capacity and mechanism of the hydrogel for key metal ions.
• To explore the potential of the hydrogel in mitigating food safety risks associated with heavy metal pollution.

Main Methods:

• Synthesis of a composite hydrogel using hydrotalcite and alginic acid via hydrothermal methods.
• Chemical crosslinking of the hydrogel with calcium ions.
• Quantification of heavy metal adsorption using Atomic Absorption Spectrometry (AAS) and analysis using isotherm and kinetic models.

Main Results:

• The composite hydrogel demonstrated high adsorption capacities for Cu²⁺ (325.73 mg/g), Zn²⁺ (284.78 mg/g), and Pb²⁺.
• Adsorption followed the Langmuir isotherm model and pseudo-second-order kinetic model, indicating chemisorption.
• The composite hydrogel outperformed individual hydrotalcite and alginate hydrogels in adsorption efficiency.

Conclusions:

• The developed composite hydrogel is a highly effective adsorbent for cationic heavy metals in wastewater.
• This material offers a promising solution for heavy metal remediation in food-related industries.
• The study highlights the potential of composite hydrogels for enhancing food safety by removing toxic metal contaminants.