ABSTRACT In this study, novel pyrazine-2-carboxylate derivatives of calix[4, 8]arene have been synthesised and fully characterised. Furthermore, this study presents removal of carcinogenic azo dyes [Reactive Black 5 (RB5), Trapaeolin 000 (TP), Chicago Sky Blue (CSB), Methyl Orange (MO) and Evans Blue (EB)] from the aqueous solution by solid-liquid extraction using these novel compounds. The maximum sorption of azo dyes was achieved at pH 3. Calix[8]arene derivative (3) showed higher sorption as it formed a more stable complex with azo dyes than calix[4]arene derivative (6). An excellent regeneration for at least five times in sorption capacity indicates that calix[8]arene derivative (3) was highly applicable for the removal of carcinogenic azo dyes from industrial wastewater. The stoichiometric ratio between the calixarene derivatives (3 and 6) and selected azo dyes was estimated through job’s plots. Graphical Abstract

中文翻译：

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新型吡嗪-2-羧酸酯取代杯[4, 8]芳烃衍生物有效去除致癌偶氮染料

摘要 本研究合成并充分表征了杯[4, 8]芳烃的新型吡嗪-2-羧酸衍生物。此外，本研究展示了通过固体去除水溶液中的致癌偶氮染料 [活性黑 5 (RB5)、Trapaeolin 000 (TP)、芝加哥天蓝 (CSB)、甲基橙 (MO) 和伊文思蓝 (EB)]使用这些新化合物进行液体提取。偶氮染料的最大吸附在 pH 值为 3 时实现。杯 [8] 芳烃衍生物 (3) 显示出更高的吸附，因为它与偶氮染料形成的复合物比杯 [4] 芳烃衍生物 (6) 更稳定。吸附容量至少为五倍的出色再生表明杯[8]芳烃衍生物（3）非常适用于工业废水中致癌偶氮染料的去除。杯芳烃衍生物（3 和 6）与选定的偶氮染料之间的化学计量比是通过工作图估计的。图形概要