Investigating the Efficiency of Different Papaya Seeds Masses as Natural Coagulants in the Textile Wastewater Treatment Process

Abstract

Industrial effluent contaminants comprise insoluble materials, heavy metals, and organic and inorganic substances. The textile sector needs help with waste management due to the various colours and chemicals involved. Coagulation-flocculation is commonly used to treat industrial effluent because it eliminates suspended particles, organic contaminants, turbidity, and colour. However, using chemical coagulants can lead to high expenses and generate large amounts of non-biodegradable waste and metallic residues in the treated water, which may introduce new pollution and disease risks. There is growing interest in a sustainable, non-toxic, and biodegradable alternative, specifically using natural coagulants from plant sources such as papaya dry seeds. This research examines the efficiency of various amounts of papaya seed coagulant (1.0 g, 1.5 g, 2.0 g, 2.5 g) with a consistent solvent of 1.0 M NaCl. SEM and XRD analyses were performed to characterise dry papaya seeds, revealing a porous and uneven surface structure. Assessments of Chemical Oxygen Demand (COD), turbidity, colour, and pH were used to determine the effectiveness of papaya seed purification on a textile wastewater sample. The results demonstrate that papaya dry seeds are highly effective coagulants. The optimal mass for papaya seed usage was 2.5 grams, achieving 92.72% effectiveness with a 20 ml coagulant dose. Furthermore, the best colour removal rate was 44.96% with a 25 ml dose at 2.5 grams of papaya seed mass. Additionally, the maximum COD reduction was observed with 2.0 grams of papaya seed mass and a 25 ml coagulant dose, achieving an 84.6% reduction. These findings highlight the potential benefits of using papaya seeds as organic coagulants for treating effluents from the textile industry.