朱航　陈兴祺　李世蓉　黄玺嘉　林少华

摘要：以山药为原料，开发环境友好型高分子絮凝剂。采用有机溶剂沉淀法提取山药天然有机物。通过FTIR和元素分析对山药提取物（YE）进行表征。考察山药提取物絮凝剂投加量、温度、pH、无机盐和悬浮物含量对絮凝去除直接黑G的影响。结果表明：山药提取物主要为多糖。投加YE能强化PAC去除直接黑G效果，随着YE投加量的提高，直接黑G去除率也不断提高。pH和温度对YE的絮凝活性有明显影响。在pH = 8.0～9.0时，YE则表现出良好的助凝效果。在5～25℃范围内有利于YE发挥絮凝作用。溶液中无机盐与悬浮物对YE絮凝处理水中直接黑G影响不显著。YE是一种去除水中直接黑G较理想的天然絮凝剂。

关键词：絮凝剂; 絮凝;山药提取物;多糖;直接黑G

中图分类号：X703.1文献标识码：A文章编号：1006-8023（2019）03-0069-05

Study on Coagulation Removal Characteristics of Direct Black G by Yam Extract

ZHU Hang， CHEN Xingqi， LI Shirong， HUANG Xijia， LIN Shaohua*

（School of Civil Engineering， Nanjing Forestry University， Nanjing 210037）

Abstract：Chinese yam was used as raw material to develop environmental friendly macromolecular flocculant. Natural organic matters were extracted from Chinese yam by organic solvent precipitation method. Yam extract （YE） was characterized by FTIR and elemental analysis. The effects of flocculant dosage， temperature， pH， inorganic salt and suspended solid on coagulation removal of direct black G were investigated. Results showed that the yam extract was mainly composed of polysaccharide. The coagulation removal of direct black G by PAC could be enhanced by addition of YE. The removal of direct black G increased with the increase of dosages of YE. Both of pH and temperature had significant influences on flocculation activity of YE. YE showed good coagulation aid effect at pH=8.0-9.0. The optimal temperature range for YE flocculant was 5-25℃. The presence of inorganic salt and suspended solid did not affect direct black G removal significantly. YE is an ideal natural flocculant for removing direct black G from water.

Keywords：Flocculant; coagulation; yam extract; polysaccharide; direct black G

0引言

野外施工如國防建设及重大基础设施、森林采伐等，人员饮水安全是关系到项目能否顺利实施的关键之一[1]。混凝工艺简单、能够有效地去除水中的悬浮物、胶体杂质及细菌等，是水或废水处理常规工艺环节。但传统的无机絮凝剂，如聚合氯化铝，具有一定毒性，容易对人类的神经系统造成损伤[2]。有机合成絮凝剂因为絮凝效果好，价格便宜而广泛使用，但这些有机絮凝剂又存在不易生物降解，或者其单体（如丙烯酰胺）具有神经毒性，甚至有潜在致癌性等[3]。因此有必要研究开发低毒、经济和高效的絮凝剂。

大量排放的印染废水对水环境和人体健康构成了严重威胁。针对水中染料的处理方法，如光催化法、复合材料降解法、电解法和膜分离法等[4-8]，存在工艺相对复杂，处理成本高等问题。……