Granular adsorbent targets micro-pollutants

A biomaterial capable of removing micro-pollutants such as pesticides and pharmaceuticals from waste water has won a science award.

Henrik Hagemann CEO CustoMem
Henrik Hagemann CEO CustoMem

Micro-pollutants, which also include high performance chemicals and heavy metals, only make up a small proportion of overall pollution but can be extremely difficult to deal with using existing treatment processes, rendering freshwater unusable.

The new granular adsorbent, developed by Imperial College London spin-out CustoMem, is capable of binding and removing a range of micro-pollutants, including Perfluorinated Compounds (PFCs).

These pollutants, which are highly toxic to humans and animals, are used in Aqueous Film Forming Foams (AFFFs) used for firefighting, and can also be found in fluoropolymer-coated cookware, sports clothing, and medical equipment.

The adsorbent, known as CustoMem Granular Media (CGM), is a nanocellulose-based material, according to Shayne Petkiewicz, business development manager at CustoMem.

The material can selectively capture micro-pollutants ten times faster than traditional adsorbent materials such as anion-exchange media and granular activated carbon, he said. It can also adsorb two times more pollutant, and once saturated can be regenerated more than five times.

“We have used our biomaterials and synthetic biology skills to introduce new properties, both at the micro and macro level, which allow us to do things that other media can’t do quite as well,” said Petkiewicz. “So we have been able to increase the surface area, and we have also changed the surface chemistry in such a way that it can target compounds of choice,” he said.

The material can be tailored to target particular strains of pollutant, he added.

Any captured pollutants can be removed with CustoMem’s proprietary wash, and disposed of or re-used.

The material has been awarded the £25,000 Venture Prize by the Armourers and Brasiers Company. It is designed and manufactured through a biological production process, without the use of hazardous chemicals.

The adsorbent could be used at navy and air force bases where AFFFs are used for firefighting.

But it could also be used to treat other pollutants, such as those found in wastewater from the mining, pharmaceuticals and textile industries.

CustoMem is based at Imperial College’s Incubator and supported by SynbiCITE, the Royal Academy of Engineering, Innovate UK, and Climate–KIC.