Innovative Use of Pineapple Peel as a Coagulant: Insights from Factorial Analysis

Abstract

This study aims to optimise the preparation and application of pineapple peel coagulant to maximise turbidity reduction from simulated wastewater. The investigated factors include the drying time (0 and 24 h), settling period (0 and 24 h), coagulant dosage (1 and 2 ml), and agitation speed (10 and 50 rpm). The turbidity values were measured using the HACH Portable Turbidimeter (model 2100Q) and the viscosity values were obtained using the Brookfield Viscometer (model LV-DVII). Design Expert software designed the experimental setup and a two-level factorial design was used to analyze the data in accordance with that. Based on the analysis, the best condition to maximise turbidity reduction was suggested using 24 h dried pineapple peel and a settling period of 24 h. At this condition, the highest turbidity reduction of 71% was achieved, from 40 to 11.6 NTU. In contrast, undried pineapple peels with no settling period achieved a significant 61.69% turbidity reduction, demonstrating practical and time-efficient benefits. The p-value of 0.0003 shows that the chosen model is significant. The R² value of 0.8795 explains the fitted model for turbidity reduction. Therefore, investigating the production of coagulants from pineapple peel waste may be an alternative method to reduce turbidity while producing a useful product.