ICDSUPL4-E023

Volume: 4, 2025
4th International PhD Student’s Conference at the University of Life Sciences in Lublin, Poland:
ENVIRONMENT – PLANT – ANIMAL – PRODUCT

Abstract number: E023

DOI: https://doi.org/10.24326/ICDSUPL4.E023

Published online: 9 April 2025

ICDSUPL, 4, E023 (2025)

Sorption of phosphates on Rockfos® materials at extreme temperature conditions

Beata Zawadzka^1,2*, Tadeusz Siwiec¹, Michał Marzec¹

¹ Department of Environmental Engineering, University of Life Sciences in Lublin, Leszczyńskiego 7, 20-069 Lublin, Poland

² Mirosław Zalewski MONT-SAN, Rogoźnica 75, 21-560 Międzyrzec Podlaski, Poland

^{* Corresponding author: beata.zawadzka@up.lublin.pl}

Abstract

Phosphorus is one of the nutrients that is quite restrictively limited in sewage discharged into the environment. Removal of phosphorus compounds from wastewater is most often done in a conventional way, biologically or chemically. Despite this, the problem of excess phosphorus in discharged sewage is still common, especially in the case of small municipal sewage treatment plants scattered throughout Poland. For such treatment plants, unconventional methods of removing phosphorus from sewage have been used, consisting of sorption of the nutrient on appropriately selected sorbents. These are innovative methods, due to the possibility of recovering and reusing phosphorus compounds, the resources of which are depleted on Earth. The effects of using Rockfos® material to remove phosphorus from sewage have been described in many articles. The positive correlation between the change in solution pH and the degree of phosphorus reduction suggests the ongoing chemisorption process. The aim of the work was to determine the phosphorus sorption isotherms at low and high temperatures. Phosphorus sorption isotherms were studied at extreme temperatures of 5 °C and 25 °C, the variables were: PO₄^3– concentration in the test solution 0.5 mg PO₄^3–/dm³, 1 mg PO₄^3–/dm³ and 2 mg PO₄^3–/dm³ and the grain size of the material, i.e. 1.0–1.6 mm, 1.6–2.5 mm and 2.5–5.0 mm. Langmuir isotherms were analyzed in general and linear form according to linearization: Langmuir, Lineweaver-Burk, Scatchard and Eadie- Hoffsie. The non-uniformity of the Rockfos® material showed a strong influence on the coefficient of determination R2. The studies also showed a significant relationship between the sorption capacity, which strongly depended on the phosphate concentration in the initial solution.

Keywords: sorption, sorption isotherms, phosphorus, Rockfos® material

How to cite

B. Zawadzka, T. Siwiec, M. Marzec, 2025. Sorption of phosphates on Rockfos® materials at extreme temperature conditions. In: 4th International PhD Student’s Conference at the University of Life Sciences in Lublin, Poland: Environment – Plant – Animal – Product. https://doi.org/10.24326/ICDSUPL4.E023