文献类型：期刊文献

英文题名：Unraveling Amphiphilic Poly(N-vinylcaprolactam)/Water Interfaceby Nuclear Magnetic Resonance Relaxometry: Control of ClathrateHydrate Formation Kinetics

作者：Wang, Dong[1];Li, Dongfang[1];Kelland, Malcolm A.[2];Cai, Haokun[3];Wang, Jie[1];Xu, Ying[1];Lu, Ping[1];Dong, Jian[1]

机构：[1]Shaoxing Univ, Coll Chem & Chem Engn, Shaoxing 312000, Zhejiang, Peoples R China;[2]Univ Stavanger, Fac Sci & Technol, Dept Chem Biosci & Environm Engn, N-4036 Stavanger, Norway;[3]Ningbo Fiber Inspect Inst, Ningbo Acad Prod & Food Qual Inspect, Ningbo 315048, Zhejiang, Peoples R China

年份：2022

卷号：38

期号：16

起止页码：4774

外文期刊名：LANGMUIR

收录：SCI-EXPANDED(收录号：WOS:000792765400029)、、EI(收录号：20221712011633)、Scopus(收录号：2-s2.0-85128529158)、WOS

基金：This work was supported by the National Natural Science Foundation of China (21973061 and 21674063).

语种：英文

外文关键词：Crystal growth - Crystallization kinetics - Gas hydrates - Gas industry - Kinetics - Molecules - Natural gas - Nuclear magnetic resonance - Phase interfaces - Process control

外文摘要：Water-soluble amphiphilic polymers are vital chemicals in the oil and gasindustry to retard crystal growth of hydrocarbon hydrateviasurface adsorption andsuppress nucleation of a pristine hydrate nucleus, thereby preventing formation of hydrateblockages inflow lines during oil and natural gas production. Apart from a few theoreticalmodeling studies, an experimental method to study the polymer/water interface in thecrystal growth is critically needed. Here, water motions in the hydration shells of anexemplary kinetic inhibitor, poly(N-vinylcaprolactam), during hydrate formation from thetetrahydrofuran/water system are revealed via nuclear magnetic resonance relaxometry.Unequivocal experiments show that the pivotal interfacial water in the tightly bound stategradually freezes at rates depending on the polymer molecular weight (MW). This issupported by nonfreezable water analysis, which is correlated to the inhibition time. Thepolymers tune the kinetics of the hydration processviainteraction with and perturbation ofthe water molecules. The free water component in the polymer solution crystallizes at avery slow rate when in partially restricted mobility, whereas the bound water componentincreases in the reaction, with the polymer/water interface serving as the reaction sites. The appropriate MW (including average MWand polydispersity values) of the inhibitive polymers can give rise to maximal retardation of the hydrate crystal growth. This workwill help control other multiphase crystallization kinetic processes through the design of inhibitors or promoters functioning in theinterface