HPAM-biomass phenol-formaldehyde resin dispersion system: evaluation of stability

Phenol-formaldehyde resins combined with polymers have a wide range of industrial applications as plugging agents for profile control and enhanced oil recovery. Due to the structural resemblance between lignin and phenol, there are possibilities for environmentally friendly phenol-formaldehyde resin manufacturing. Sulfonated lignin–based phenol-formaldehyde resin was synthesized by partially replacing phenol with lignin, which improved the utilization rate of lignin and achieved the purpose of environmental preservation and resource conservation. Partially hydrolyzed polyacrylamide is the most widely used polymer in chemical methods for enhanced oil recovery. However, the stability of reservoirs with high salt and high temperatures is weak under these conditions. To solve the problem of low oil recovery in high-salt reservoir environments, polymer flooding is adopted, which utilizes high-molecular-weight polymers to raise the viscosity of injected fluids, thereby improving sweep efficiency and altering mobility ratio between oil and injected fluid. We focus on the stability study of different molecular weights partially hydrolyzed polyacrylamide combined with sulfonated lignin – based phenol-formaldehyde resins in metal ions and surfactants. The zeta potential and hydrodynamic diameter of the partially hydrolyzed polyacrylamide – sulfonated lignin – based phenol-formaldehyde resin system in Ca2+ were measured by dynamic light scattering and static light scattering, and the dispersion stability was analyzed. The interfacial energy – modified DLVO theory was introduced to evaluate the stability of its colloidal solution, which made it possible to predict the aggregation behavior of sulfonated lignin – based phenol-formaldehyde resin and the co-migration process of metal cations in real time.