Mg-doped keratin-based biochar@hydrogel composite: An efficient cadmium and lead adsorbent

Area of Science:

• Environmental Science
• Materials Science
• Chemical Engineering

Background:

• Heavy metal contamination poses significant environmental and health risks.
• Conventional biochar adsorbents have limitations in capacity and separation.
• Keratin waste is an underutilized resource.

Purpose of the Study:

• To develop a recyclable and efficient adsorbent for heavy metal remediation.
• To valorize keratin waste into a functional material.
• To enhance the adsorption capacity and separability of biochar-based adsorbents.

Main Methods:

• One-pot synthesis of magnesium-doped keratin-based biochar@hydrogel composite (MBC@HG).
• Characterization of composite properties including surface area and metal content.
• Adsorption experiments for Cd2+ and Pb2+ using kinetic and isotherm models.

Main Results:

• MBC@HG exhibited a 3D network structure with excellent mechanical strength and stability.
• Adsorption capacity for Cd2+ and Pb2+ increased with higher MBC content.
• Maximum adsorption capacities reached 141 mg g-1 for Cd2+ and 291 mg g-1 for Pb2+.
• Adsorption followed pseudo-second-order kinetics, reaching 80% capacity within 1 hour.

Conclusions:

• The developed MBC@HG composite is a highly efficient and recyclable adsorbent for heavy metal removal.
• This strategy effectively valorizes keratin waste.
• The composite offers a sustainable solution for water and soil remediation.