Valuable Iron Recycling In High Arsenic Acid Waste Water

Industrial waste water and so on metallurgy, mining, chemical industry has characteristics of deep color and high acidity. Certain waste water also includes the violently poisonous matter of arsenic compound. Present processing of the arsenic waste water methods are not only consume the massive manpower, the physical resource and the financial resource, takes the massive farming, also has the hidden trouble to the ecological environment; And, in the harmless processing of waste water, because the iron and the arsenic altogether deposit but is disadvantageous to the valuable metal recycling, waste resources. This paper researches acidity arsenic metallurgy waste water of the valuable element recycling, highly effective utilization, having the important theory and the practical significance.This paper takes the acidity arsenic metallurgy waste water as the research object, according to the chemical deposition behavior difference of arsenic and iron ion in the different pH value solution, by the selective deposition to recycle iron so that highly effective utilization. Studying pH value, mixing speed, temperature, alkali density to the influence of recycle. In the singlefactor experiment foundation through three levels three factorsorthogonal experiments, optimized the craft parameter, had the best craft condition of selective recycling iron:pH value is 13.5, mixing speed is 800rpm and alkali density is 10mol/L. Inspecting the dry temperature, the drying time to the influence of deposition color and the industrial production feasibility, determineing the appropriate craft condition is:drying temperature 80℃, drying time 8-9h.Studying the preparation of iron oxide red, purifing the best selective deposition with the alkali, and then grinding powdery to prepare iron oxide red by burning. Inspecting the influence of burning temperature and the time to the product color, the purity, the appearance and the oilness, and then determines the appropriate craft condition. According to thermodynamics and the chemical equilibrium migration principle, purifies the iron deposition under the high temperature and high alkali condition, determines appropriate condition of purification:alkali density 3mol/L, lixiviating time 120min; the preparation of iron oxide red:burning temperature 900℃, burning time 60min.The color of production is bright red, the purity is 90.56% and the oilness is 23.4g/100g. The appearance of iron oxide red is rule, conforming to requirements of GB1863-89, the particle size of iron oxide red is 60-70nm and belongs to a nanometer iron oxide red. Through thermodynamic analysis, getting the relation ofΔGθwith T in the preparation processing is:Using methods of Kissinger, many elevations of temperature speed and the Doyle-Ozawa to calculate the energy in the main processing of burning, the result are 286.47 kJ·mol-1,294.23 kJ·mol-1 and 289 kJ·mol-1, they may mutually verify. The peedrate equation of the iron oxide red preparation is:...