Rocha, S.A.F.d.; Rocha, B.C.d.S.; Moraes, L.E.Z.d.; Villaça, J.M.P.; Scapin, D.; Santo, D.E.; Gonzalez, R.d.S.; Junior, O.V.; Peron, A.P. Evaluation and Simulation of the Adsorption Capacity of Octocrylene Sunscreen on Commercial Carbon and BiocharBiochar is a carbon-rich material created from biomass decomposition in low-oxygen conditions. It has important applications in environmental remediation, soil improvement, agriculture, carbon sequestration, energy storage, and sustainable materials, promoting efficiency and reducing waste in various contexts while addressing climate change challenges. More from Spent Coffee Beans. Processes2024,12,1249. https://doi.org/10.3390/pr12061249

Octocrylene, a common sunscreen ingredient, poses significant environmental concerns due to its persistence in water bodies and resistance to conventional wastewater treatments. A recent study evaluated the efficacy of two adsorbents, commercial activated carbonActivated carbon is a form of carbon that has been processed to create a vast network of tiny pores, increasing its surface area significantly. This extensive surface area makes activated carbon exceptionally effective at trapping and holding impurities, like a molecular sponge. It is commonly More and biochar derived from spent coffee grounds activated with zinc chloride (ZnCl2), in removing octocrylene from water.

Both adsorbents achieved nearly 100% removal efficiency in experimental trials. The adsorption kinetics indicated that the process stabilized within 40 minutes for both materials. Among the tested models, the Langmuir isotherm best described the adsorption behavior of biochar, highlighting its higher adsorption capacity (37.822 µg/mg) compared to commercial carbon (33.602 µg/mg).

Additionally, the study conducted toxicity tests using Allium cepa (onion) roots to assess the phytotoxic, cytotoxic, and genotoxic impacts of octocrylene before and after adsorption. Results showed that the octocrylene solution was highly toxic before treatment but became non-toxic after adsorption with either adsorbent, demonstrating the effectiveness of both materials in detoxifying the pollutant.

This research highlights the potential of using biochar from spent coffee grounds as a cost-effective and sustainable adsorbent for removing harmful organic pollutants like octocrylene from wastewater, offering a promising solution to enhance current water treatment processes.