A study of silver sorption from aqueous solutions by solid-phase modified poly(n-thiocarbamoyl-3-aminopropyl silsesquioxane) ; Изучение сорбции серебра из водных растворов твердофазномодифицированным Поли(n-тиокарбамоил-3-аминопропилсилсесквиоксаном)

Sorption properties of poly(3-aminopropylsilsesquioxanes) modified with thiourea groups were studied to predict the possibility of using poly(n-thiocarbamoyl-3-aminopropylsilsesquioxanes) (TCPS) in separation and concentration techniques. The sorbents were synthesized by the sol-gel method followed by solid-phase modification using ammonium thiocyanate or thiosemicarbazide as modifiers. It was established that sorbents with the highest content of thiocarbamide functional groups (modified with ammonium thiocyanate) enabled quantitative and selective recovery of Ag (I) from strongly acidic solutions. The degree of Ag (I) recovery slightly decreases at pH5, which is associated with increasing competitive sorption of Cu (II), Ca (II), Mg (II), Mn (II) and Fe (III). The highest recovery of Ag (I) for TCPS-0.63 and TCPS-0.68 was achieved at pH ranging from 4 to 8 (degree of recovery was 55–68% (TCPS-0.63); 21–26% (TCPS-0.68 )); at the same time, there was a predominance of competitive sorption of Ca (II), Mg (II), Mn (II), and Fe (III). Based on the aforementioned, it can be concluded that the sorbents modified with ammonium thiocyanate are characterized by high concentration of attached thiocarbamide groups that make them suitable for the selective recovery of Ag (I) ions from multicomponent solutions at pH 1–2. Keyword: solid-phase extraction, selective recovery, separation of metals, concentration, functional materials, polysilsesquioxane, thiourea, thiocarbamide, silver, sol-gel method. ; С целью прогнозирования возможности использования поли(n-тиокарбамоил-3-аминопропилсилсесквиоксанов) (ТКПС) в методах разделения и концентрирования изучены сорбционные свойства поли(3-аминопропилсилсесквиоксанов), модифицированных тиомочевинными группами. Сорбенты синтезированы золь-гель методом с последующим твердофазным модифицированием с использованием в качестве модификатора тиоцианата аммония или тиосемикарбазида. Установлено, что сорбенты с наибольшим содержанием функциональных тиокарбамидных групп (модифицированные с ...