Rapid HCFC-141b hydrate formation and high-density cold storage in the presence of acid ester surfactants

Abstract

To improve HCFC-141b hydrate production, eco-friendly nonionic surfactants were used as promoters to enhance hydrate formation. Stearic acid polyoxyethylene ester (SG) effectively improve HCFC-141b hydrate formation, and the promotion effect is influenced by the hydrophilicity and mass fraction of surfactant. Ethylene oxide (EO) numbers of SG series surfactants affect on hydrate nucleation induction time and cold storage density. Surfactants with appropriate HLB values have better promotion effects. Hydrate has shorter induction times and higher cold storage density with SG-20. When the concentration of SG-20 is 1 %, the induction time reduces to 36 min, and the cold storage density is up to 245.1 kJ/kg, which is the optimal addition amount for HCFC-141b hydrate production. Comparing the three systems, the HCFC-141b hydrate system with 1 wt% SG-20 has the best cycling stability.