The crucial challenge associated with water-based drilling fluids for the extraction of shale gas is the inhibition of clay hydration in the drilling operation. The inhibition efficiency of shale inhibitors is determined by the content of particular groups in the molecule. In this report we studied the inhibition performance, inhibition mechanism, and environmental friendliness of three inhibitors containing different amine and hydroxyl groups. It is known that amine groups can replace cations in the molecular chain, decrease basal spacing, exhibit superior inhibition performance, and have better biodegradability. However, hydroxyl groups are less toxic. Thus, the inhibitor molecule should contain both amine and hydroxyl groups, where amine groups detarmine inhibition capacity, and hydroxyl groups provide excellent biotoxicity.

中文翻译：

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粘土水化抑制剂的分子结构设计原则

与用于开采页岩气的水基钻井液相关的关键挑战是在钻井作业中抑制粘土水化。页岩抑制剂的抑制效率取决于分子中特定基团的含量。在本报告中，我们研究了三种含有不同胺和羟基的抑制剂的抑制性能、抑制机制和环境友好性。众所周知，胺基可以取代分子链中的阳离子，减小基间距，表现出优异的抑制性能，并具有更好的生物降解性。然而，羟基的毒性较小。因此，抑制剂分子应同时含有胺基和羟基，其中胺基消除抑制能力，而羟基提供优异的生物毒性。