Valorisation of residual iron dust as Fenton catalyst for pulp and paper wastewater treatment

• Type: Article in International Scientific Journal
• Date: 2022

Authors

João Manuel R. S. Tavares (Author) FEUP; Sarinho, L (Author) Other; Neves, MC (Author) Other; Nunes, MI (Author) Other

Journal

Title: Environmental Pollution

Vol. 310 No. 119908

ISSN: 0269-7491

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 0 Citations

Scopus

Other information

Authenticus ID: P-00X-3ZK

DOI: 10.1016/j.envpol.2022.119850

Abstract (EN): In this work, the performance of residual iron dust (RID) from metallurgic industry was assessed as Fenton catalyst for the treatment of real pulp bleaching wastewater. The focus was on the removal of recalcitrant pollutants AOX (adsorbable organic halides), by a novel, cleaner, and cost-effective circular solution based on a waste-derived catalyst. The behaviour of RID as iron source was firstly assessed by performing leaching tests at different RID:wastewater w/v ratios and contact time. Afterwards, RID-catalysed homogeneous and heteroge-neous Fenton processes were conducted to maximise AOX removal from the pulp bleaching wastewater. Reusability of RID was assessed by a simple collect-and-reuse methodology, without any modification. Similar AOX removal under less consumption of chemicals was achieved with the novel heterogeneous Fenton process. Reaction in the bulk solution was the main pathway of AOX removal, given that the low surface area and porosity of the material did not allow for a high contribution of surface reaction to the overall performance. Moreover, AOX removal was similar over two consecutive treatment cycles, with Fenton process being responsible for 56.7-62.1% removal of AOX from the wastewater, and the leaching step adding 11.4-13.2%. At the end of treatment, COD either decreased (1st cycle) or remained unchanged (2nd and 3rd cycle). The operating cost of the optimised heterogeneous Fenton was 3-11% lower than under conventional Fenton process. This work presented a novel, circular solution based on a low-cost waste-derived catalyst, advancing the knowledge needed to foster industrial application of such technologies to increase industrial environmental performance and efficiency.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 8