Optimization of environmentally friendly coagulants based on circular economy and SDGs in the rubber latex industry in Indonesia

This study presents a novel approach to optimizing environmentally friendly coagulants in line with the circular economy (CE) and Sustainable Development Goals (SDGs) principles for the rubber latex industry. Unlike conventional chemical coagulants that pose environmental hazards, the proposed formulation using lemon and plant-based gums offers a sustainable, non-toxic, and biodegradable alternative. The novelty lies in combining natural materials with statistical optimization using Response Surface Methodology (RSM), thereby providing a replicable model for eco-innovation in latex processing. This study aimed to optimize lemon-based natural coagulants in the rubber latex industry by applying Response Surface Methodology (RSM), thereby contributing to sustainable production in line with the Circular Economy (CE) and the Sustainable Development Goals (SDGs). The effects of lemon concentration, latex volume, and temperature on coagulation time were systematically evaluated using a central composite design (CCD). The results showed that lemon concentration and temperature significantly influenced coagulation time (P < 0.05). The optimal condition, namely 19.82 ml of lemon and 81.07 ml of latex, reduced coagulation time to only 2.16 minutes. In conclusion, this study is among the first to demonstrate the effectiveness of lemon as a rapid, biodegradable, and low-cost alternative to synthetic chemicals for coagulation in rubber processing. The optimization promotes reduced environmental impact and production costs, aligning with CE principles and supporting SDG targets on responsible production, economic growth, and climate action. Additionally, the results provide a replicable and environmentally friendly strategy for rubber-producing regions.