Study On Adsorbing Nitrite In Water By Immobilized Hemoglobin

Nitrite is widely existed in soiK water and food, It can change hemoglobin(Hb) into methaemoglobin (Fe31) in men's body. Methaemoglobin can't carry oxygen, so men will be poisoned because of lacking oxygen. Nitrite also react with amine to form product of N-nitrosoamines, and N-nitrosoamines is a carcinogenic substance,. So it is necessary to study the method of removing nitrite hi water.Useing immobilized hemoglobin to remove nitrite is a new method which hasn't been reported by now. we test three different materials to immobilize hemeglobin: Oxycellulose P and glutaraldehyde, we find that it is the best method for hemoglobin immobilized by glutaraldhyde to adsorb nitrite. This method is very simple and does not result in the loss of hemoglobin.We aslo study a series of factors which might influence the adsorption of nitrite(Such as concentration^ temperature pH, reaction time and the co-existent ions ect). When temperature keeps at 25 . pH is 6.5 and the immobilized hemoglobin adsorb nitrite for five hours, the removal rate could be up to 90%; the adsorption balance time is 12 hours; maximun adsortion quantity of NO^ is 37.14mg/g. Vc can be used to elute the nitrite adsorbed by immobilized hemoglobin, Which is effective in the condition of pH=l. After the immobilized hemoglobin be repeatedly used for ten times, adsorption rate is still up to 90%.In dynamic test, We let nitrite solution pass through glass column at a speed of 0.5ml/min. The adsorption rate is up to 90%. When we purify the wastewater containing 1 Omg/L NO in this method, the concentration of NOz in purifying ater is below 0.8mg/L, at the time of the volume of elutant going beyound 150ml.Experiment proved that it is utility for us to use immobilized hemoglobin to treat nitrite wastewater.