# Possibilities of Managing Waste Iron Sorbent FFH after CO2 Capture as an Element of a Circular Economy

## TL;DR

This paper explores how to manage waste from a CO2 capture sorbent, focusing on minimizing waste volume and recovering iron compounds when justified.

## Contribution

The study introduces a strategy for managing waste iron sorbent as part of a circular economy approach.

## Key findings

- Dewatering is the most effective method for reducing waste volume from FFHCO2.
- Recycling FFHCO2 as a coagulant or through bioleaching is not technologically viable.
- Recovery of iron compounds should be considered only if environmentally and economically justified.

## Abstract

With a growing need to reduce greenhouse gas emissions, innovative carbon dioxide sorbents are being sought. One of the sorbents being tested is nanoparticle ferric hydrosol (FFH). In parallel with sorbent testing, it is also necessary to test the used sorbent after carbon dioxide capture (FFHCO2) and to develop an optimal method for its processing and management. The research described in this article evaluated the potential use of FFHCO2 in dewatering, coagulation and bioleaching processes. The research results indicate that the basic strategy for dealing with waste FFHCO2 sorbent should be to minimize the amount of waste by volume reduction—dewatering. Recycling of FFHCO2 as an iron waste coagulant or its processing products by bioleaching had no technological justification. It is only proposed to recover the material—iron compounds—if it is environmentally and economically justified.