Testing the Removal of Microplastics from Surface Water Using Okra Mucilage Combined with Polyaluminium Chloride (PAC)
Main Article Content
Abstract
Recently, microplastics (MPs) have become an emerging pollutant. Coagulation-flocculation is a physicochemical method that uses chemical coagulants to remove MPs, but the disadvantages include high cost and chemical residues that are harmful to the environment. Okra mucilage is a low-cost natural coagulant that has been found to be capable of removing MPs from aquatic environments. The objective of this study was to test the environmentally friendly combination of okra mucilage with Polyaluminium chloride (PAC) to remove MPs from surface water. The results showed that okra mucilage did not change the pH of the water and was suitable for the optimal pH range of PAC. The ratio of okra mucilage to PAC was 2:1 (mL:mg) per liter of water. The optimal coagulation time to remove microplastics in surface water was 15 min with a removal efficiency of about 62.96% of MPs. However, depending on the state of the floc/coagulant, whether it is settling or floating, we still need to develop an optimal method to separate the floc/coagulant from the water environment.
Keywords:
Microplastics, Okra mucilage, Polyaluminum chloride (PAC), removal, surface water.
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No. 2, 2023, ttps://doi.org/10.47750/pnr.2023.14.S02.291.
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