The adsorption behavior of hydroxypropyl guar gum onto quartz sand

Abstract Hydroxypropyl guar gum (HPG) is an important guar gum derivative commonly used as thickener for fracturing fluids in the field of petroleum industry. This paper presents an investigation of the adsorption properties of HPG on quartz sand using a modified measurement method. The effects of pH, temperature, inorganic salt, alcohols and polymers on the adsorption density of HPG were also studied. The results showed that the effect of pH and temperature from 20 °C to 60 °C on the adsorption capacity could be negligible. Sodium chloride (NaCl) has little effect on HPG adsorption; however, potassium chloride (KCl), calcium chloride (CaCl 2 ) and magnesium chloride (MgCl 2 ) increased the adsorption capacity while sodium sulfate (Na 2 SO 4 ) and trisodium phosphate (Na 3 PO 4 ) resulted in the decrease of the adsorption density. In addition, monobasic alcohol has no significant effect on HPG adsorption while the addition of polybasic alcohol increased the adsorption. The addition of partially hydrolyzed polyacrylamide (HPAM) decreased the adsorption capacity. The X-ray diffraction (XRD) and scanning electron microscopy (SEM) test demonstrated that HPG was only adsorbed on the surface of quartz sand and not absorbed into the quartz. The Fourier infrared spectroscopy showed that the HPG adsorption mechanism on quartz sand was caused by a hydrogen bond and Van der Waals' forces.