摘要
采用溶解-沉淀法,以未污染的中空纤维膜为原料,以四氢呋喃为溶剂,乙醇为沉淀剂,对膜中的聚砜材料进行回收,为后续对污染聚砜膜的回收提供依据,借此找到一种回收利用聚砜类废弃膜材料的可行方法。试验考察回收工艺中乙醇浓度、聚砜膜与溶剂配比(溶剂比)、聚砜膜与沉淀剂配比(沉淀剂比)对聚砜分离回收工艺的影响,通过正交试验确定最适溶解-沉淀工艺条件。结果表明,乙醇浓度和沉淀剂比对回收工艺影响显著;得到最适回收工艺条件为:80%乙醇,溶剂比1 g:25 mL,沉淀剂比1 g:250 mL。在最适回收工艺条件下得到聚砜的平均回收率为87.5%,纯度为90.6%。
The paper is aimed to present our research on the polysul- fone （PSF） recovered from unpolluted PSF hollow fiber membranes by means of dissolution-precipitation method, using tetrahydrofuran as solvent and ethanol as precipitator. As is well known, membrane separation technology has been widely used in various industrial fields and scientific research in the last decades. However, there are large stocks of used membranes, especially in wastewater treatment field, which have been discarded as industrial solid waste. It is because the used membranes have lost their original properties and functions due to fouling, aggressive cleaning procedures, etc. The purpose of this study is to provide a reliable basis for the recovery of fouled PSF membranes in future work and to find a feasible way of recovering the discarded PSF membrane materials and finally reduce the environ- mental pollution. The effects of different concentration of ethanol, ra- tios of PSF membrane weight to solvent volume （solvent ratio） and ra- tios of PSF membrane weight to precipitant volume （precipitation ra- tio） on the dissolution-precipitation recovery process were investigated in detail. In addition, the optimum experimental recovery conditions were obtained through orthogonal experiment in our research. The analysis of orthogonal experimental data showed that ethanol concen- tration and precipitation ratio could significantly impact the recovery process. On the other hand, the solvent ratio was proven to have little effect on the recovery process. The results of our research indicated that, under optimum recovery process conditions of 80% ethanol as precipitant, the solvent ratio 1：25 （g/mL） and the precipitation ratio 1：250 （g/mL）, the PSF average recovery rate from the unpolluted PSf hollow fiber membrane could be achieved up to be 87.5 % , with the purity which can reach 90.6 % . Thus, this method is able to pro- vide a guidance for the follow-up works of recovering old （discarded） fouled PSF membrane.
出处
《安全与环境学报》
CAS
CSCD
北大核心
2011年第5期86-89,共4页
Journal of Safety and Environment
关键词
环境工程学
聚砜
中空纤维膜
溶解-沉淀法
回收
environmental engineering
polysulfone
hollow fibermembrane
dissolution-precipitation method
mem-brane recycling
