Polycyclic aromatic hydrocarbons (PAHs) removal by sorption: A review

Area of Science:

• Environmental Chemistry
• Environmental Science
• Materials Science

Background:

• Polycyclic aromatic hydrocarbons (PAHs) are persistent organic micro-pollutants due to their hydrophobic nature.
• Environmental and human health concerns drive research into PAH removal methods.
• Sorption is a key method for PAH removal due to their low aqueous solubility and high sorptive affinity.

Purpose of the Study:

• To consolidate findings on adsorbent media used for PAH removal from aqueous solutions.
• To review factors influencing the sorption process for PAHs.
• To provide a comprehensive overview of PAH sorption literature published between 1934 and 2015.

Main Methods:

• Literature review of 142 studies on PAH removal using sorption.
• Analysis of various adsorbent media, including activated carbon, biochar, and modified clay minerals.
• Identification of key parameters affecting PAH sorption efficiency.

Main Results:

• High removal efficiencies reported for adsorbents like activated carbon (100%), biochar (98.6%), and modified clay minerals (>99%).
• PAH removal efficiency is significantly influenced by adsorbent particle size, pH, temperature, salinity, and adsorbent production methods.
• Consolidation of findings reveals a need for standardized information for future research and method design.

Conclusions:

• Sorption is an effective method for removing PAHs from aqueous solutions and immobilizing them in soils.
• Understanding the factors affecting sorption is crucial for optimizing PAH removal strategies.
• This review provides a consolidated resource for researchers and practitioners in the field of PAH remediation.