Removal of mercury from sulfuric acid production

Purpose and goal:

In this project, we have scaled up a newly developed technique for removal of mercury from sulfuric acid produced in smelters. The technique is based on electrochemical alloy formation and is a result of recent research at Chalmers University of Technology. We have assembled a prototype and scaled up from 50 ml lab experiments to treatment of 20 litres of sulfuric acid, without loss of efficiency.

We have also worked on the development of stable and efficient electrodes, and in collaboration with Boliden compiled a list of requirements for further upscaling in a pilot project. Expected results and effects:

The results from this project have taken us to TRL 5, and provided important knowledge on how to scale up the technique and implement a Pilot Project on industrial scale, reaching an even higher TRL. Continuing the development of stable high surface area electrodes has been identified as the most important challenge in order to scale up to industrial applications.

Our technology will contribute to the UN Sustainable Development Goals 3, 6, 9 and 12 and we also believe that it can contribute to affect policies for more stringent requirements on mercury concentrations in sulfuric acid. Approach and implementation:

The project was led by Chalmers who in close cooperation with the startup company Atium organized the work. Atium were responsible for development of the prototype, while Chalmers planned and carried out the tests. Boliden took part as industrial partner with expertise within smelters, and provided sulfuric acid from the Kokkola smelting plant.

The Swedish Environmental Institute IVL assisted with mercury analysis and Chalmers Innovation Office took part as advisor. All project partners participated in meetings throughout the project to discuss results and upcoming tests.