亲水性氨基酸抑制四氢呋喃水合物形成的动力学机理

Kinetic mechanism of hydrophilic amino acid inhibiting the formation of tetrahydrofuran(THF) hydrate

亲水性氨基酸作为新型天然气水合物(以下简称水合物)抑制剂是国内外相关研究的热点,但其对水合物形成影响的内在机制目前尚不明确,并且对于其与其他水合物动力学抑制剂(KHIs)复配的协同抑制机理的认识仍存在着较大的争议。为此,基于四氢呋喃(THF)水合物的形成模拟实验,厘清了甘氨酸、L-精氨酸及其与聚乙烯吡咯烷酮(PVP)复配对水合物形成的影响规律,并结合多种实验方法揭示了其内在机理。研究结果表明:①甘氨酸对水分子具有较强的扰动作用,使其对水合物的形成具有较强的抑制性,添加量为1.0%时抑制效果为最佳;②L-精氨酸对水分子具有较强的束缚作用,使其对水合物的形成具有较强的抑制性,在较低添加量的范围内,其对水合物形成的抑制性随添加量的增大而逐渐增强;③亲水性氨基酸与PVP复配对水合物的形成具有协同抑制作用,当抑制剂添加总量为1.0%时,甘氨酸与PVP K90复配的协同抑制能力更强。结论认为,该研究成果为新型水合物抑制剂的研发提供了实验数据和理论基础。

Hydrophilic amino acid,as a new kind of hydrate inhibitor,is the hot spot of domestic and foreign relevant studies.At present,however,its intrinsic mechanism influencing the formation of hydrate is not figured out,and the understandings on its synergistic inhibition mechanism with other kinetic hydrate inhibitors(KHIs)are still controversial.In this paper,the influence laws of glycine,L-arginine and its combination with polyvinylpyrrolidone(PVP)on the formation of hydrate were clarified by experimentally simulating the formation of tetrahydrofuran(THF)hydrate,and the intrinsic mechanism was revealed by virtue of various experimental methods.And the following research results were obtained.First,glycine has such a strong disturbance action on water molecules that it has stronger inhibition on the formation of hydrate.And when its dosage is 1.0%,its inhibition effect is the best.Second,L-arginine has a stronger binding action on water molecules,so it has stronger inhibition on the formation of hydrate.And in the range of lower dosages,its inhibition on the formation of hydrate increases gradually with the increase of its dosage.Third,the combination of hydrophilic amino acid and PVP has synergistic inhibition on the formation of hydrate.And the synergistic inhibition ability of combined glycine and PVP K90 is stronger when the total dosage of inhibitors is 1.0%.In conclusion,the research results provide experimental data and a theoretical basis for the research and development of new hydrate inhibitors.