Castor oil-based quaternary ammonium surfactant (COQA) was synthesized by an ester-exchange reaction of refined castor oil (CO) (raw material) with N,N -dimethyl ethanol amine followed by quaternization with epichlorohydrin (ECH). Its surface activity and structural features were determined. The critical micelle concentration (CMC) of the surfactant at 25 °C was 1.79 × 10 −3 mol/L. The surface tension of an aqueous COQA solution at CMC was 38.19 mN/m. Subsequently, the synthesized COQA was used to modify attapulgite (ATP) by binding it to the surface of ATP. The change in the morphology of the modified-ATP (M-ATP) was attributed to the presence of the COQA bound to the surface of the rod-shaped crystals, although the crystal structure of the silicate did not change. Compared to ATP, the microstructure of the M-ATP was less rigid.

中文翻译：

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蓖麻油基季铵表面活性剂的合成及其在凹凸棒石改性中的应用

蓖麻油基季铵表面活性剂 (COQA) 是通过精制蓖麻油 (CO)（原料）与 N,N-二甲基乙醇胺进行酯交换反应，然后与环氧氯丙烷 (ECH) 进行季铵化反应而合成的。测定了其表面活性和结构特征。25℃时表面活性剂的临界胶束浓度(CMC)为1.79 × 10 -3 mol/L。在 CMC 处 COQA 水溶液的表面张力为 38.19 mN/m。随后，合成的 COQA 通过将其与 ATP 表面结合来修饰凹凸棒石 (ATP)。改性 ATP (M-ATP) 形态的变化归因于结合到棒状晶体表面的 COQA 的存在，尽管硅酸盐的晶体结构没有改变。与 ATP 相比，M-ATP 的微结构刚性较小。