Wastewater contaminants strengthen the production of green hydrogen

The research carried out by the RMIT University has developed an experimental invention to transform the high contaminating load of wastewater into an advantage to make green hydrogen which could reduce dependence on fresh water – a rare resource in many regions of the world.

With more than 80% of global wastewater rejected in the untreated environment, this research offers the possibility of transforming this environmental responsibility into stimulated productivity.

The team’s approach operates some of the wastewater contaminants to accelerate hydrogen production and overcome high contaminants of contaminants which normally make water unusable.

The team’s latest work – which involved the University of Melbourne, Australian Synchrotron of the University of New South Wales – constitute previous breakthroughs, including an innovation that quickly eliminates water microplastics using magnets and a technique stimulating hydrogen production using sea water.

“Wastewater exploitation as a catalyst modifier for sustainable hydrogen production” is published in ACS electrochemistry.

How innovation works

The associate professor of researcher, Nasir Mahmood, of the Rmit’s School of Science, said that the team had found a way to capture the platinum, the chrome and the nickel of other metals in the water, then put these elements to work to improve the production of green hydrogen.

“The advantage of our innovation on others to produce green hydrogen is that it uses the inherent materials of wastewater rather than requiring purified water or additional steps,” said Mahmood.

Their experimental invention is in the form of electrodes, which are key components to divide water into hydrogen and oxygen. The electrode is manufactured with an absorbing carbon surface which attracts the metals of wastewater to form stable and effective catalysts in the conduct of electricity, helping to accelerate the fractionation of water.

The materials used to produce the special carbon surface area are made from agricultural waste – another profitable aspect of innovation which contributes to an increasing circular economy.

“The catalyst is accelerating a chemical reaction without being consumed in the process,” said Mahmood.

“Metals interact with other elements of wastewater to stimulate the electrochemical reactions necessary to divide water into oxygen and hydrogen.”

As part of the experiments, the team used wastewater samples in a container with two electrodes – an anode (positive) and a (negative) cathode – and propelled the water suffocation process with renewable energies. When electricity flows in water, it causes a chemical reaction.

At the cathode, the water molecules gain electrons and form gas hydrogen. At the anode, the water molecules lose electrons and form oxygen.

The result is a separation of water into its basic components, hydrogen and oxygen, which could then be collected and used.

“Produced oxygen can be reintegrated into wastewater treatment factories to improve their efficiency by reducing organic content,” said Mahmood.

The device made it possible to separate from the water continues for 18 days during laboratory experiences, with a minimum drop in performance during this period. As part of the experiments, the team used wastewater which had undergone treatment, including the elimination of solid waste, organic matter and nutrients.

Opportunities for industry and government collaborations

RMIT develops a platform of catalytic systems capable of using difficult water resources such as wastewater and seawater and this last invention of concept proof is another example of systems under development.

The co -directed researcher, Professor Nicky Eshtiacyhi, said that the latest RMIT innovation could potentially reduce the high cost of wastewater treatment while transforming it into something precious – a source of green hydrogen.

“Our innovation addresses both the reduction of pollution and the water shortage, for the benefit of the energy and water sectors,” said Eshtiaghi, of the RMIT engineering school. “Using wastewater, the process helps reduce pollution and uses materials considered to be waste.

“We want to work with companies around the world that approach energy and waste as a cost and sustainability challenges, as well as the water authorities.

“Collaborations could focus on the development of commercial systems to use this large -scale technology.”

Following steps

The co-researcher, Dr. Muhammad Haris, said that additional research was necessary to refine the catalyst process, which makes it even more effective and adapted to commercial use.

“The method must be tested with different types of wastewater to ensure that it works universally,” said Haris, of the engineering school.