Removal of phosphate from brewery wastewater by cerium(III) chloride originating from spent polishing agent: Recovery and optimization studies

Paweł Lejwoda; Barbara Białecka; Maciej Thomas

doi:10.1016/j.scitotenv.2023.162643

Removal of phosphate from brewery wastewater by cerium(III) chloride originating from spent polishing agent: Recovery and optimization studies

Sci Total Environ. 2023 Jun 1:875:162643. doi: 10.1016/j.scitotenv.2023.162643. Epub 2023 Mar 6.

Authors

Paweł Lejwoda¹, Barbara Białecka², Maciej Thomas³

Affiliations

¹ Central Mining Institute in Katowice, Department of Environmental Monitoring, Plac Gwarków 1, Katowice 40-166, Poland. Electronic address: plejwoda@gig.eu.
² Central Mining Institute in Katowice, Department of Environmental Monitoring, Plac Gwarków 1, Katowice 40-166, Poland.
³ Cracow University of Technology, Faculty of Environmental Engineering and Energy, Warszawska 24, Cracow 31-155, Poland.

PMID: 36889387
DOI: 10.1016/j.scitotenv.2023.162643

Abstract

This paper presents the possibility of using hydrated cerium(III) chloride (CeCl₃∙7H₂O) recovered from a spent polishing agent containing cerium(IV) dioxide (CeO₂) to remove phosphate and other impurities from brewery wastewater (phosphate 43.0 mg/L, total P 19.8 mg/L, pH 7.5, COD_(Cr) 827 mg O₂/L, TSS 630 mg/L, TOC 130 mg/L, total N 46 mg/L, turbidity 390 NTU, colour 170 mg Pt/L. CCD (Central Composite Design) and RSM (Response Surface Methodology) were applied to optimise the brewery wastewater treatment process. The removal efficiency (mainly of PO₄^3-) was the highest under optimal conditions (pH 7.0-8.5, Ce³⁺:PO₄^3- molar ratio of 1.5-2.0). Applying recovered CeCl₃ under optimal conditions yielded a treated effluent in which the concentration of PO₄^3- decreased by 99.86 %, total P by 99.56 %, COD_(Cr) by 81.86 %, TSS by 96.67 %, TOC by 60.38 %, total N by 19.24 %, turbidity by 98.18 %, and colour by 70.59 %. The Ce³⁺ ion concentration in the treated effluent was 0.058 mg/L. These findings suggest that CeCl₃‧7H₂O recovered from the spent polishing agent may constitute an optional reagent for phosphate removal from brewery wastewater. The sludge from wastewater treatment can be recycled for Ce and P recovery. The recovered cerium can be reused for wastewater treatment, creating a cyclic cerium cycle in the process, and the recovered phosphorus can be used, for example, for fertilization purposes. The optimised cerium recovery and application is in accordance with the ideas of circular economy.

Keywords: Beer; Circular economy; ICP-MS; RSM; Sediments.