Continuous-flow metal biosorption in a regenerable Sargassum column.

Area of Science:

• Environmental Science
• Biotechnology
• Materials Science

Background:

• Heavy metal pollution poses significant environmental risks.
• Biosorption using natural materials offers a sustainable remediation approach.
• Seaweed biomass is a cost-effective and abundant biosorbent material.

Purpose of the Study:

• To evaluate the long-term metal biosorption performance of raw Sargassum filipendula.
• To investigate the biosorption-desorption behavior over multiple cycles in a packed-bed column.
• To determine the stability and efficiency of seaweed biomass for continuous copper removal.

Main Methods:

• Packed-bed flow-through column experiments for copper removal.
• Ten consecutive sorption-desorption cycles using CaCl2/HCl solution for elution.
• Analysis of biosorbent weight loss, copper biosorption capacity, breakthrough time, and mass-transfer zone.
• Determination of "life-factors" for column service time and critical bed length.

Main Results:

• Sargassum filipendula maintained a stable copper biosorption capacity of approximately 38 mg Cu/g over ten cycles.
• Column service time decreased from 25.4 h to 12.7 h, and critical bed length increased from 28 cm to 34 cm.
• Elution efficiency using CaCl2/HCl reached up to 100%, with concentration factors ranging from 16-44.

Conclusions:

• Raw Sargassum filipendula demonstrates robust copper biosorption capabilities suitable for continuous wastewater treatment.
• While performance slightly degrades over cycles, the biomass remains effective, indicating good reusability.
• The study provides key parameters for designing and optimizing seaweed-based biosorption systems for copper remediation.