Use of Bilecik province lefke stone, bentonite clay and tree of heaven (Ailanthus altissima) biochar in phosphorus removal from wastewater

For environmental and human health, treating wastewater to render it harmless and reusing it is crucial. High phosphorus concentrations, in particular, accelerate the growth of cyanobacteria. Due to their high nutrient content, wastewater causes problems such as increased oxygen consumption, eutrophication, and toxicity in the receiving environment. To maintain water quality and reduce the risk of eutrophication in the receiving environment, phosphorus treatment may be necessary in addition to nutrients such as carbon and nitrogen to ensure ideal nutrient ratios. Technologies aimed at removing and recovering phosphorus from wastewater through chemical, physical, and advanced biological methods are constantly evolving. In the adsorption method, the physical and chemical properties of the adsorbent, its ability to adsorb phosphorus, its cost, and its ease of acquisition are paramount. In this study, various modifications of readily available local lefke stone, tree of heaven biochar material, and bentonite clay were used as adsorbents for phosphorus removal from wastewater. The study was conducted in artificially created wastewater environments with phosphorus contents of 20, 40, and 60 ppm, and pH values of 4, 7, and 10. Doses of each adorbent were used at 0,5%, 2%, and 5%, respectively. The mixture was kept in an orbital shaker at 150 rpm for 60 minutes, then filtered to determine the phosphorus content of the liquid. The results were compared considering removal percentage and adsorption capacity values. According to the study results, it was understood that the thermally modified form of Lefke stone, which has a significant reserve in Bilecik province, can be used as a very effective adsorbent (95,273 – 97,451%) for phosphorus removal in wastewater. Adjusting the adsorbent dose depending on the increased phosphorus content was also found to be important. As a second recommendation, it was concluded that the use of thermal modifications of bentonite clay at appropriate doses could provide phosphorus removal at a level of 54,964%. Finally, the Biochar adsorbent, derived from the invasive tree of Heaven in the region, was found to provide 42,953% phosphorus removal in a low pH environment and at the appropriate dosage. Using these resources will also offer significant advantages due to their affordability, ease of access, and natural nature.