College of Resources and Environment, Chengdu University of Information Technology, Chengdu, Sichuan, 610225, China.
College of Resources and Environment, Chengdu University of Information Technology, Chengdu, Sichuan, 610225, China.
Chemosphere. 2017 Aug;181:759-766. doi: 10.1016/j.chemosphere.2017.04.119. Epub 2017 Apr 26.
This paper focused on the production and characteristics of a bioflocculant by using swine wastewater and its application in removing arsenite from aqueous solution. A series of experimental parameters including bioflocculant dose, calcium ions concentration, and solution pH value on arsenite uptake were evaluated. Results have demonstrated that a bioflocculant of 3.11 g L was achieved as the maximum yield after 60 h fermentation, with a main backbone of polysaccharides. Maximum arsenite removal efficiency of 99.2% can be reached by adding bioflocculant in two stages: 3 × 10% (w/w) in the 1.0 min's rapid mixing (180 rpm) and 2 × 10% (w/w) after 2.0 min's slow mixing (80 rpm) with pH value fixed at 7. Negative Gibbs free energy change (ΔG) indicated the spontaneous nature of arsenite removal. Arsenite was removed by the bioflocculant through bridging mechanisms.
本文主要研究了利用猪粪废水生产生物絮凝剂的方法及其在去除水中亚砷酸盐方面的应用。实验考察了生物絮凝剂投加量、钙离子浓度和溶液 pH 值等因素对亚砷酸盐去除效果的影响。结果表明，在发酵 60 h 后，生物絮凝剂的最大产量为 3.11 g/L，其主要成分为多糖。通过分两次添加生物絮凝剂（第 1 次快速混合时添加 3×10%（w/w），第 2 次缓慢混合时添加 2×10%（w/w），搅拌速度分别为 180 rpm 和 80 rpm），可使亚砷酸盐的去除效率达到 99.2%。固定 pH 值为 7。负的吉布斯自由能变化（ΔG）表明亚砷酸盐的去除是自发的。生物絮凝剂通过桥联机制去除亚砷酸盐。
