Performance of natural bentonite clay in sugarcane juice clarification: a comparative study of sedimentation and centrifugation processes

Sugarcane plays a central role in Brazil’s sugar-energy industry, with 2024/2025 production forecast at 678.67 million tons, despite adverse climate conditions. Juice clarification is a key stage in processing, directly affecting impurity removal, color, and overall efficiency. This study evaluated the use of natural bentonite clay (“argilabofe”) as a clarifying agent, comparing sedimentation and continuous centrifugation. The clay was characterized through XRD, FTIR, and TG/DTG, confirming its composition and thermal stability. A 2² Central Composite Rotatable Design was applied to analyze the influence of pH (6.7–7.3) and clay concentration (0.4–0.5%) on ICUMSA color and turbidity. Raw juice presented an ICUMSA color of 24,723.32 and turbidity of 1,980 NTU. pH significantly impacted clarification efficiency. Sedimentation reduced color by about 67%, while centrifugation proved highly effective in turbidity reduction, achieving values below 20 NTU (~100%). Findings suggest natural bentonite is a promising aid for industrial sugarcane juice clarification, improving both sugar quality and process performance.