Metal sorption by peat and algae treated peat: kinetics and factors affecting the process

Area of Science:

• Environmental Science
• Water Treatment Technologies
• Bioremediation

Background:

• Heavy metal contamination poses significant risks to water resources.
• Conventional water purification methods can be costly and less effective for certain contaminants.
• Peat is a natural sorbent, but its efficiency can be improved.

Purpose of the Study:

• To investigate the efficacy of microalgae-treated peat for heavy metal removal from contaminated water.
• To compare the metal sorption capabilities of raw peat versus microalgae-modified peat.
• To assess the influence of water hardness and pH on heavy metal uptake.

Main Methods:

• Peat was treated with microalgae to create a composite sorbent.
• Sorption experiments were conducted using a multimetal solution (Cu, Cd, Ni, Zn, Pb, Co).
• The effects of water hardness (Ca²⁺) and pH on metal uptake were evaluated.

Main Results:

• Microalgae treatment significantly increased the metal uptake capacity of peat.
• Lead (Pb) and Copper (Cu) exhibited the highest affinity for both raw and treated peat.
• Algal treatment reduced sorption equilibrium time from 72 h to 24 h and lessened the impact of water hardness.

Conclusions:

• Microalgae-treated peat is a highly effective biosorbent for heavy metal removal, particularly Pb and Cu.
• This novel approach offers a faster and more robust method for water purification compared to using peat alone.
• The modified peat demonstrates good performance across a range of pH conditions and reduced sensitivity to water hardness.