四丁基铵盐对甲烷水合物生成动力学的调控机理研究

Gas hydrate technology for gas storage is an alternative for natural gas storage and transportation, and how to improve the formation rate and the gas density is the focus of this research. Tetrabutylammonium salts were found to be effective to thermodynamically stabilize gas hydrates. Thus adding tetrabutylammonium salts is expected to be an innovative method for reducing costs of gas hydrate technology for methane storage and transportation. This project will firstly study on the regulatory mechanisms of methane hydrate kinetics by tetrabutylammonium salts on a macro scale, by exploring the kinetic properties of hydrate formation and dissociation under the influence of different additive concentrations, temperatures, pressures and other factors. Secondly, on a micro level, the project will determine the lattice type, crystal morphology and the occupation of methane molecules in lattice using XRD, SEM and in situ Raman spectroscopic analysis. Lastly, based on the macroscopic and microscopic experimental data, the project will theoretically reveal the regulatory mechanisms of methane hydrate formation kinetics by tetrabutylammonium salts, by establishing the kinetic model of methane hydrate formation using a parameter, resulted as the influence of tetrabutylammonium salts. With multi scale experimental and theoretical study, this project will provide data support and theoretical guidance for methane storage and transportation using new hydrate technology.

水合物法储运气体技术是一项新的的气体储运方式，如何提高水合物生成过程的生成速度和储气密度是其中的关键。四丁基铵盐类添加剂被认为是一种高效的水合物热力学促进剂，因此利用四丁基铵盐类添加剂有望成为一种降低水合物法储运甲烷气体成本的新技术。本项目首先系统性地考察不同四丁基铵盐浓度、温度、压力等因素对甲烷水合物生成分解过程的影响，从宏观上掌握四丁基铵盐对甲烷水合物动力学的调控机理；再利用X射线衍射仪、低温扫描电镜和原位拉曼光谱仪从微观上系统性地确定四丁基铵盐作用下的甲烷水合物结构类型、晶体形态及甲烷分子在其中的分布状况；在宏观和微观实验基础上，通过引入四丁基铵盐作用参数，建立水合物生成动力学模型，最终从理论上揭示四丁基铵盐对甲烷水合物生成动力学的调控机理。本项目的多尺度实验理论研究可以为新型水合物法储运甲烷气体提供实验数据和理论支持。

四丁基铵盐甲烷二元水合物是一种新型的水合物法气体储运技术和潜在的水合物开采利用支撑方法。项目研究了四丁基铵盐甲烷二元水合物分解热力学性质和生成动力学特性，利用微观拉曼光谱仪、X射线衍射仪和低温扫描电镜测试分析了半笼型水合物结构类型、气体分子的笼中分布、水合物表面形貌等特征，并使用水合物动力学计算模型快速明确地预测了水合物的生长过程。结果表明：四丁基铵盐浓度和温度对二元水合物的储气密度和快速生长速度分别具有决定性调节作用；甲烷气体对半笼型水合物产生了HS结构诱导作用，并增强了其储气能力；水合物生成动力学计算模型可以有效预测水合物生长体系的平衡时间、标准生长速度和耗气进程。项目明确了四丁基铵盐对甲烷水合物生长过程和结构特性的调控机理，可为水合物法高效储气提供实验参考数据和理论支持。项目已经发表论文7篇，申请专利7项，培养青年人才1名和硕士研究生1名。