Magnetic nanomaterials for pollution control: an efficient solution to remove PAHs from water and air

Innovative materials for targeted and efficient pollution control

Pollution by organic micropollutants, particularly polycyclic aromatic hydrocarbons (PAHs), is a major challenge for industries committed to environmental responsibility. Produced by the incomplete combustion of fossil fuels or biomass, these compounds mainly originate from the oil and chemical industries, as well as domestic heating. Their proven toxicity to human health and ecosystems makes it essential to develop effective and sustainable remediation solutions.

In this context, research teams from ICPEES and IPCMS (members of Carnot MICA) have developed recyclable magnetic composite nanomaterials capable of adsorbing these pollutants with remarkable efficiency.

Nanomaterials based on graphene and iron oxides

The researchers designed new nanocomposites combining graphene sheets, tannic acid, and magnetic iron oxide nanostructures. Their architecture was optimized to maximize adsorption performance.

• In water, these materials demonstrate outstanding efficiency, capturing more than 95% of PAHs, whether as individual compounds or in mixtures, and within a very short time. Their magnetic properties also enable easy recovery and reuse of the particles.
• In air, despite challenges related to semi-volatile compounds, initial tests show effective adsorption of molecules such as naphthalene.

Concrete applications for industry

These advances open the door to several high-potential applications for industrial stakeholders:

1. Water and air purification

The nanomaterials can capture organic pollutants, including those bound to carbon particles. Their recyclability makes them a sustainable and cost-effective solution for companies aiming to reduce their environmental footprint.

2. Pollutant measurement and quantification

A selective adsorption method has been developed to pre-concentrate PAHs prior to analysis, reducing interference from other organic compounds. This approach significantly improves measurement accuracy in both air and water.

An innovation for sustainable industry

These nanomaterials meet the growing regulatory requirements faced by industry while opening new opportunities, including:

• wastewater treatment in collaboration with ENGEES,
• filtration and removal of pathogens, including certain viruses,
• miniaturized analytical devices for near real-time pollutant monitoring.

The results obtained have led to the validation of a four-year ANR project conducted with the company Chromatotec, focused on PAH air sampling using a portable device. The objective is to selectively trap compounds, concentrate them, and then thermally desorb them for precise analysis.

What are the benefits for industry?

By integrating these technologies into their processes, companies can:

• significantly reduce their environmental footprint,
• adopt innovative and high-performance materials,
• benefit from a reusable, sustainable, and cost-effective solution,
• strengthen regulatory compliance.