二硫代氨基甲酸盐的絮凝作用机理及除油性能

Flocculation mechanism and oil removal performance of dithiocarbamate

用2种端氨基聚醚化合物Jeffamine-T403和Jeffamine-D230作原料分别合成了二硫代氨基甲酸盐型絮凝剂DTC-1和DTC-2,利用红外光谱分析,确认了产物分子的结构.以高岭土悬浊液为处理对象,通过考察DTC分子结构、投药量和Fe2+络离子浓度对絮凝的影响及Zeta电位的变化,讨论了DTC的作用规律和机理.结果表明,与DTC-2相比,DTC-1与Fe2+络合可形成网状超分子结构,故产生的絮体具有较好的网捕作用.金属离子为Fe3+时,絮凝性能较差.DTC-1除油能力强,在Fe2+的配合下,20mg/L的投加量可使油浓度从93.9,404.3,878.6mg/L分别降至1.1,3.2,6.4mg/L.

Two dithiocarbamate-type flocculants, DTC-1 and DTC-2, were synthesized with two amine-terminated polyether compounds, Jeffamine-T403 and Jeffamine-D230. The molecular structures of the products were characterized by infrared spectra. The effects of DTCs＇ molecular structures, dosage and ferrous ion concentration on both turbidity removal in the kaolite suspensions and zeta potential were investigated to elucidate the flocculation mechanism. The net capturing of coordination supramolecular polymer, which was formed by DTC and Fe^2＋ chelating, was identified to be the main flocculation mechanism. Flocculation performance was found to be worse when Fe^3＋ was used as the chelating ion instead of Fe^2＋. In addition, 20mg/L DTC-1 with 10mg/L Fe^2＋ was able to decrease the oil concentrations from 93.9, 404.3, 878.6mg/L to 1.1, 3.2, 6.4mg/L, respectively.