Abstract

New extraction systems have been developed for recovery of nickel(II) from concentrated saline chloride medium (1 M) via the use of the chelating extractant, N,N′ Bis(salicylaldeyde) ethylenediimine (H₂SALEN), and different surfactants namely, cetyltrimethyl, ammonium, bromide (CTAB) and polyoxyethylene (23), dodecyl either (Brij^® 35).The effects of the main experimental parameters such as extraction time, pH, extractant concentration and surfactant concentration on the extraction process of nickel(II) with H₂SALEN alone and H₂SALEN-surfactant mixture at 30 °C were studied and compared. The findings of the examination revealed a good recovery (E = 70–80%) of nickel with H₂SALEN alone in various solvents (chloroform, toluene and methylisobutylketone) in the acidic pH range (4–5). The addition of both CTAB and Brij^® 35 to the aqueous phase resulted in a remarkable increase in the rate of nickel extraction by reducing the extraction time from 4 hours to 20–30 minutes. The stoichiometries of the extracted species and extraction constants were ascertained by slope analysis method. The surfactant-based extraction systems have shown high extractability and a fast separation of Ni (II) into chloroform than with the reported ones. The extraction mechanisms of nickel have been suggested.

摘要

通过使用螯合萃取剂 N,N' 双（水杨醛）乙二亚胺(H ₂ SALEN) 和不同的表面活性剂，开发了新的萃取系统，用于从浓氯化盐水介质 (1 M) 中回收镍 (II)，即：十六烷基三甲基、铵、溴化物（CTAB）和聚氧乙烯（23）、十二烷基（Brij ^® 35）。 提取时间、pH、提取剂浓度和表面活性剂浓度等主要实验参数对镍（II）提取过程的影响研究和比较了单独的H ₂ SALEN 和 H ₂ SALEN-表面活性剂混合物在 30 °C 下的情况。检查结果表明，镍与 H _{2 的}回收率良好 (E = 70–80%)在酸性 pH 值范围 (4-5) 中，单独使用 SALEN 溶解在各种溶剂（氯仿、甲苯和甲基异丁基酮）中。将 CTAB 和 Brij ^® 35 添加到水相中，将提取时间从 4 小时缩短到 20-30 分钟，从而显着提高了镍提取率。提取物的化学计量和提取常数通过斜率分析法确定。与报道的相比，基于表面活性剂的萃取系统显示出较高的可萃取性和将 Ni (II) 快速分离成氯仿的速度。已经提出了镍的提取机制。