| Adding inorganic salt, such as copper, iron, zinc, manganese, magnesium in the feed (especially pig and chicken feed) originated from Europe, has had wide application in our country. Preparation of CuSO4·5H2O or Cu2(OH)3Cl with copper etching liquid waste solved the waste water problem and effectively used the valuable material-copper. It is a highly efficient waste water treatment method for comprehensive utilization of resources. The content of harmful substances in feed-grade basic copper chloride was in a strict control standard, which called for lead, arsenic levels were less than10and20mg/kg, respectively. So in the recycling process of copper waste, removal of lead, arsenic is the key technology for the preparation of feed grade copper chloride. Meanwhile, effective separation copper and lead, arsenic method for the analysis of the theory and application of separation of great significance in engineering. During the process of feed additives zinc sulfate, ferrous sulfate, manganese sulfate production, wastewater generated, due to the presence of large sulfate background, on which bring the analysis of trace lead, arsenic serious interference. So exploring methods to eliminate interference for the accurate determination of arsenic and lead in sulfate wastewater and quality control in the production process both had great value.In chapter1the source, harm, characteristic of pollution of heavy metals and copper pollution in environment; main application of etching waste liquid; research development of the tribasic copper chloride were introduced. The determination of trace lead and arsenic were revievd. The objective and innovation of this paper were presented.In chapter2the trace lead in manganese sulfate, magnesium sulfate, ferrous sulfate and alkaline etching waste water was determined by flame atom absorption spectrometry with the self-absorption background correction. The effects of experimental conditions such as, burner height, band width and narrow pulse current were studied. The result indicated that the detection limits of lead were0.015,0.090,0.034, and0.058ug/mL, respectively in the blank solution of manganese sulfate, magnesium sulfate, ferrous sulfate and alkaline etching waste water, with a recovery range of96.8-104.0%. Precisions (RSD) of this method were2.6,3.4,1.9, and2.3%, respectively. The self-absorption background correction was applied to effectively eliminate the interference of matrix and background absorption. The method was simple, sensitivity, accurate stable, so it was applied to instruct the actual production. It also could solve problems of key technique which were met in product and use of feed additive.In chapter3a method for the determination of arsenic species in various waste water and feed-grade tribasic copper chloride by hydride generation-atom absorption spectrometry (HG-AAS) was studied. The effects of experimental conditions, such as flow of carrier gas, acidity, and amount of potassium borohydride and reducing agent were investigated in detail. The result indicated that under optimum conditions, the linear over the range of0.50-10.0μg/L and the detection limit was0.12μg/L. The recoveries were in the range of93.2%-105.2%and the relative standard deviation (RSD) was2.9%. The method had many advantages, such as high sensitivity, simple speed, good selectivity, less sample and less interference. The proposed method was applied to the determination of arsenic species in various waste water and feed-grade tribasic copper chloride.In chapter4inductively coupled plasma atomic emission spectrometry was developed to simultaneously determine the content of eight elements, including Zn, Cu, Cr, Pb, Cd, As, Ni and Mn in waste water. Satisfactory linearity of the calibration curves of eight elements was obtained, all their correlation coefficients over0.9994. The detection limits of these elements were found in the range from0.0007to0.0085μg/mL. The relative standard deviations of the results were less than5.4%and recoveries were in the range of94.0%-105.0%. The proposed method has been applied to the determination of these elements in waste water with satisfactory results.In chapter5the lead and arsenic in alkaline etching waste liquor were directly removed by co-precipitation with mixed nascent calcium carbonate-ferric hydroxide. The co-precipitation conditions, such as the settling time, temperature, pH and the amount of carrier elements, were investigated. The results of optimal processing parameters indicated that for1L alkaline etching waste liquor at55℃and a pH of9.5, addition of2.3g of ferric chloride,10g of calcium chloride and10g of sodium carbonate led to removal rates for lead and arsenic of92.4%and94.6%, respectively.In chapter6a new and effective synthesis of feed-grade tribasic copper chloride was developed using alkaline etching waste liquor. The obtained tribasic copper chloride powder was characterized by XRD and electron microscopy. Results showed the feed grade tribasic copper chloride crystallites were obtained by a simple precipitation route using purified alkaline etching waste liquor and hydrochloric acid as the starting materials at65-75℃in the pH range of4.5-5.5. The contents of lead and arsenic of tribasic copper chloride were7.35and3.54mg/kg, respectively, that was obviously less than GB/T21696-2008. The structure of the obtained TBCC was characterized by XRD. The results showed that a monoclinic structure of TBCC The particle size of TBCC crystallites were in a range from50to200μm.In chapter7the overall conclusion of this paper was given. |
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