高锰酸钾氧化处理高浓度丙烯腈有机废水的条件探索

Researches on Potassium Permanganate Oxidation of the High-concentrated Acrylonitrile Wastewater

海水提铀螯合树脂制备过程中产生大量丙烯腈等有机废水,CODCr高达110 770 mg.L-1。作为主要有毒污染物的丙烯腈沸点为77.1℃,因此可利用分馏工艺收集75～78℃的馏分以期回收大部分丙烯腈。96～98℃的馏分占废水体积的90%以上,其CODCr为59 220 mg.L-1,需进一步氧化处理才能达标排放。剩余少量高沸点有机物只占废水总量的3%左右,可焚烧处理。以96～98℃馏分为研究对象,经一次高锰酸钾氧化即可使其CODCr降为3 800 mg.L-1左右;经2次高锰酸钾氧化处理CODCr为414 mg.L-1,达到腈纶污水的三级排放标准。高锰酸钾氧化时,通过正交试验,探讨了高锰酸钾浓度、pH值、温度、氧化时间等因素对馏分的处理效果的影响。通过实验发现高锰酸钾氧化时的最佳条件:c(KMnO4)3.165 mol.L-1,pH2～3,反应温度100℃,氧化时间30 min,为此类废水的处理提供了有效的工艺和可靠的参数。

In the preparation of chelating resin for extracting uranium from seawater, it has produced a large a- mount of high - concentrated aerylonitrile wastewater, of which the CODcr is up to 110 770 mg/L. Acrylonitrile is the main toxic pollutant of the wastewater , whose boiling point is 77.1 ℃, so that the wastewater can be utilized fraction- ation process and the most fraction is collected at 75℃ to 78℃. The distillate at 95℃ -98℃ is accounts for 90% of the total wastewater volume, and its CODCr is 59 220 mg ·L-1. This distillate will be needed further treatment to meet the integrated wastewater discharge standards. Then the remaining amount of high boiling point organic com- pounds accounted for only 3% of total wastewater, which can be burned. In this paper, the distillate at 95℃ to 98℃ is researched with potassium permanganate oxidation process, the effect of which is dicussed by using orthogonal test which are concentration of potassium permanganate, pH value, temperature and oxidation time. Through the experi- ment discovered that the best testing conditions of potassium permanganate oxidation is realized when c （ KMnO4 ） = 3. 165 mol · L-1 , pH =2 -3, temperature at 100℃, and oxidation time on 30 min, to provide effective and reliable parameter for this kinds of wastewater treatment