【作者】 高波；

【导师】 杨运泉；

【作者基本信息】 湘潭大学 ， 化学工程， 2011， 硕士

【摘要】 磷化作为金属表面处理技术的一种被广泛应用,在化工、冶金、汽车、航天航空、船舶等领域都有着广泛的应用。然而磷化过程中必然会产生以磷酸铁和磷酸锌为主要成分的固体废弃物磷化渣,如果任意排放固废磷化渣势必将对环境造成二次污染。所以对固废磷化渣资源化的研究具有极其重要的意义。从白色固废磷化渣中提取及其有价值的磷、铁物质并使其转化为经济价值和社会效益都比较高的产品。本文开发以白色固废磷化渣与烧碱处理,提取其中具有价值的磷、铁资源并对其进行综合利用的新工艺。通过对湖南某公司的白色固废磷化渣的成分进行化学分析得出,其中的主要离子PO4^3-、Fe³⁺、Zn²⁺的质量分数分别为51.8%、27.5%和2.35%,以磷酸铁和磷酸锌为主要的形式存在于白色固废磷化渣中。本文以制备十二水磷酸钠,并在此基础上进一步研究合成纳米羟基磷灰石（HAP）和磷酸,从而对白色固废磷化渣的资源化进行研究。十二水磷酸钠的制备:本实验配制质量分数为30%的NaOH溶液,并且在110°C和搅拌的条件下,以磷化渣与烧碱的质量比为1.25:1将NaOH溶液缓慢加到磷化渣中反应2h后,加入适量的水来严格控制pH为10¹1后,继续反应0.5h,此时固废磷化渣中PO4^3-提取率达91.45%。反应后过滤得Na3PO4溶液,蒸发、结晶、过滤后得到十二水磷酸钠晶体,且其质量分数高达98.55%;纳米羟基磷灰石的制备:在搅拌和有超声波辅助的条件下,采用化学沉淀法将上述中的Na3PO4溶液缓慢滴加到饱和的Ca（OH）₂溶液中反应获得纳米HAP,并且使用红外吸收光谱（FT-IR）、X射线衍射（XRD）以及扫描电镜（SEM）对纳米HAP粉末进行表征分析。分析结果表明,在常温和有超声波辅助的条件下,控制Na3PO4溶液的滴加速度为0.3mL/min,然后使用无水乙醇来洗涤沉淀物,可获得质量分数高达99.5%、粒径50nm左右、高结晶度以及高分散性的纳米HAP粉末产品。磷酸的制备:在常温和搅拌的条件下,将上述中的Na3PO4溶液缓慢加入到Ca（OH）₂溶液中反应制备出HAP,再将HAP与硫酸反应制备出磷酸。实验结果表明:当反应时间为2.5h,酸过量系数1.02,液固比2.5:1以及反应温度75±3℃,从磷酸钠溶液到磷酸反应的过程中,磷酸根的转化率可达96.87%。更多还原

【Abstract】 Widely used as a metal surface treatment technology, phosphating process has a wide range of applications in the chemical industry, metallurgy, automobile, aerospace,shipbuilding and other fields. Bound to produce the solid waste phosphate residue, with iron phosphate.and zinc phosphate as the main component , phosphating process emits solid waste to the environment, causing secondary pollution. Therefore, the research on the process of transforming phosphate residue in the solid waste into resources has a great significance. In this paper, the new process.of treating solid waste phosphate residue with caustic soda to extract the valuable phosphorus, iron resources has been studied.Through chemical analysis, there are four elments in phosphate residue, with PO43-51.8%,Fe³⁺27.5%,Zn2+2.35% and they main exist in the form of iron phosphate.and zinc phosphate. In this work ,the methods to prepare twelve H2O phosphate sodium , nano-hydroxyapatite （HAP） and phosphoric acid have been studied to utilize the phosphate residue solid waste.Preparation of twelve H₂O phosphate sodium:At 110°C and stirring condition, as the mass ratio of 1.25:1, the NaOH solution was slowly added to the phosphate residue. After reaction about 2 hours, adding a amount of water strictly controled the pH between 10 and 11, then continued to react for 0.5 hours, At this point ,the extraction rate of PO43- in the phosphate residue turned out to be 91.45%.Finally ,Na3PO4 solution was filtered, evaporated, crystallizated, with the mass fraction of sodium phosphate crystals up to 98.55%;Preparation of nano-hydroxyapatite:In the stirring and ultrasonic condition, by chemical precipitation ,Na3PO4 solution was slowly dropped into the saturated Ca（OH）₂ solution to prepare nano-HAP, and the HAP was characterized by infrared absorption spectroscopy （FT-IR）, X Ray diffraction （XRD） and scanning electron microscopy （SEM） . The results showed that nano-HAP prepared at room temperature and under ultrasonic conditions ,at the drops rate of Na3PO4 solution at 0.3mL/min, and then washed with ethanol to precipitate had a quality such as products purity of about 99.5%, particle size of about 50nm, high crystallinity and high dispersion. Preparation of phosphate acid:Stirring at room temperature, Na3PO4 in （1） solution was added to Ca（OH）₂ solution to prepare HAP, and HAP was reacted with sulfuric acid to prepare phosphoric acid. The results showed that at the condition such as reaction time of 2.5 hours, coefficient of excess acid of 1.02, liquid to solid ratio of 2.5:1, reaction temperature of 75±3℃, the conversion rate of phosphate turned to be 96.87%.更多还原