Research on a novel citrus pectin-bentonite composite with enhanced rheological properties

ABSTRACT Conventional calcium bentonite suffers from poor rheological properties and poor static stability.To address these challenges, this study developed a novel sodium-activated bentonite composite modified with natural citrus pectin (CP) through chemical intercalation, termed Na-BT-CP. Under optimized conditions (0.8 wt% CP), the composite demonstrated a synergistic enhancement in rheological properties at 80°C, with a 44% increase in apparent viscosity and a remarkable 175% surge in the yield point-to-plastic viscosity ratio (YP/PV). The material exhibited exceptional thermal stability, maintaining viscosity fluctuations below 1.3% within the 25–100°C range, and outstanding static stability with less than 2.6% performance attenuation after 24 hours. XRD and FT-IR analyses confirmed the successful intercalation of CP into the bentonite interlayers, forming a synergistic bonding network via Na+ bridging and hydrogen bonding. This work provides a new pathway for developing high-performance, environmentally friendly drilling fluid materials using renewable resources.