Synthesis and evaluation investigation of novel kinetic hydrate inhibitors at high subcooling conditions
Kinetic hydrate inhibitors (KHIs) have gradually gained more attention in the natural gas and oil transportation field due to their remarkable inhibition performance at low dosages. However, the inhibition performance of most commercial KHIs is poor under high subcooling conditions. In this work, a radical polymerization method was used to synthesize four new KHIs by introducing the 1-vinylimidazole (VI) or vinylacetate (VAc) monomer. These newly-synthesized copolymer KHIs were characterized by Fourier Transform Infrared, 1 H nuclear magnetic resonance, and gel permeation chromatography, respectively. The cloud point of HY-201 is remarkably as high as 92.3 °C and the four KHIs are all biodegradable. Under subcooling of 10 K and 15 K, the inhibitory performance of four new KHIs and three commercial KHIs on hydrate nucleation and growth are as follows: PVP < Luvicap EG < Inhibex 501 < HY-101 < HY-201 < HY-301 < HY-401. In addition, the hydrate volume fraction of the four new KHIs at the optimal concentration of 15 K subcooling for 12 h was 13.3 %, 1.7 %, 2.4 %, and 2.1 %, respectively, which did not exceed 1/3 of the tested commercial KHIs. Further, the novel mechanism hypothesis is proposed as follows: the surface charge of the hydrate nuclei is neutralized by KHIs, and the hydrate nuclei aggregates, hindering the gas from entering the hydrate. In addition, the strong entanglement and adsorption of KHIs molecules with better inhibition performance make the hydrate lose the space for growth and expansion. Overall results highlight the great application prospects of these new KHIs in natural gas transmission based on the remarkable inhibition performance under high subcooling conditions.
危险品化学品经营许可证（带存储）