An Experimental Approach to Formulate Lignin-Based Surfactant for Enhanced Oil Recovery

The higher cost of chemical surfactants has been one of the main reasons for their limited used in enhanced oil recovery (EOR) process. Hence, the reason for developing lignin-based surfactant is to lower the cost of chemicals as it does not tie to the price of crude oil as compared to petroleum-based surfactants. Besides, lignin is biodegradable and easily extracted from plant waste. The objectives of this study are to determine the formulations of the lignin-based surfactant for EOR applications and to determine the oil recovery performance of the formulated surfactants through surfactant flooding. The lignin-based surfactants were formulated by mixing the lignin with the amine (polyacrylamide or hexamethylenetetramine) and the surfactant sodium dodecylbenzenesulfonate in a 20,000 ppm NaCl brine. Interfacial tension (IFT) of the formulated lignin-based surfactant is measured at ambient temperature using the spinning drop method. The displacement experiments were conducted at room temperature in glass beads pack holders filled with glass beads, saturated with paraffin and brine. The results of the study showed that the best formulation of lignin-based surfactant is using hexamethylenetetramine as the amine, lignin, and sodium dodecylbenzenesulfonate at 2% total active concentration. The oil recovery and interfacial tension using the lignin amine system is comparable with the commercial petroleum sulfonate system.

Synthesis and Properties of Waterborne Polyurethane (WBPU)/Modified Lignin Amine (MLA) Adhesive: A Promising Adhesive Material

A series of waterborne polyurethane (WBPU)/modified lignin amine (MLA) adhesives was prepared using modified lignin amine (MLA) as a chain extender by a prepolymer mixing process. A successful Mannich reaction was achieved during the synthesis of MLA by reacting lignin with bis(3-aminopropyl)amine. Higher tensile strength, Young’s modulus and thermal stability were recorded for WBPU/MLA adhesives with higher MLA contents. The WBPU/MLA adhesive materials were used to coat PVC substrates. The adhesive strength increased with increasing MLA content. More importantly, the MLA also enhanced the WBPU/MLA coating in terms of adhesive strength at moderately high temperatures as well as under natural weather exposed conditions. The adhesive strength was essentially unaffected with 6.48 mole% MLA in the WBPU/MLA coating after exposure to natural weather conditions for 180 days.