【作者】 李雁；

【导师】 林春绵；

【作者基本信息】 浙江工业大学 ， 环境工程， 2010， 硕士

【摘要】 硫铁矿废水系硫铁矿开采过程中或开采后产生的含铁量高、酸性强的天然废水,会严重污染周围环境。利用硫铁矿废水制备铁黑颜料,不仅可以达到处理废水消除其危害环境的目的,而且可以使废物资源化,充分利用了硫铁矿废水中的铁资源,具有重要的现实意义。本论文以硫铁矿废水为原料,探索性地研究了中和沉淀、湿法氧化法制备铁黑颜料工艺流程的可行性及较优的工艺条件,通过电解除铜和添加柠檬酸、十二烷基磺酸钠及聚乙二醇三种分散剂,探讨制备高着色力铁黑颜料的条件。结果表明:快速均匀地向硫铁矿废水中加入质量分数10%的NaOH溶液至pH值等于9,以200r/min的搅拌速度搅拌溶液3min,不加任何阴阳离子的PAM,静置沉淀120min,可使硫铁矿废水中和沉淀达到最大沉降效果且处理后上清液达标排放。中和沉淀得到的氢氧化亚铁溶胶在反应初始pH值9～10,反应温度80～90℃,反应时间2.5～3h,搅拌速度100～200r/min,烘干温度60⁸0℃条件下能制备得到铁黑颜料。在初始pH值9.5、反应温度85℃、反应时间2.5h、搅拌速度150r/min、80℃恒温烘干的工艺条件下,能制备得到较优的铁黑颜料。经过XRD、SEM及铁黑颜料技术指标检测分析,表明该铁黑颜料粒径在60nm左右,Fe₃O₄含量在95%以上,各项指标均能达到氧化铁黑颜料行业标准中一级品的要求。但铁黑颜料中Cu₂O的存在使其带有红相,并且Fe₃O₄粒子之间有明显的团聚现象。经2.0V直流电电解30min后的硫铁矿废水,通过中和沉淀、湿法氧化初期添加0.75ml质量分数1%的柠檬酸,能制备得到高着色力铁黑颜料。其经XRD、SEM、色光性能检测分析,结果表明色光更接近标准样品,基本不带红相,黑色更纯正;团聚现象有明显改进,粒径也有一定程度的减小。更多还原

【Abstract】 The pyrite wastewater which is produced during or after the iron pyrite exploitation contains lots of iron with low acidity and has a potential harm to environment. The utilization of pyrite wastewater to prepare black iron pigment has important significance. This is not only due to the treatment of the pyrite wastewater and elimination of environmental pollution, but also making wastewater to resource and recovery of iron resource from pyrite wastewater.In our study, the process feasibility and optimal conditions of black iron pigment preparation from pyrite wastewater were explored through precipitation and wet oxidation. The preparation conditions of high tinting strength black iron pigment were discussed via electrolytic removal of copper and addition of dispersants such as citric acid, sodium lauryl sulfate and polyethylene glycol.The result showed that rapidly and equably adding 10% NaOH to pyrite wastewater until the condition of pH 9, stirring rate 200r/min for 3 minuts, no PAM addition and 120 minuts precipitation resulted in the optimal effect, at the same time the wastewater reached the discharge standard.Ferrous hydroxide which got from precipitation was able to make black iron pigment through reacting at 80⁹0℃f or 2.5³h with the origimal pH of 9¹0, stirring at 100²00r/min and drying at 60⁸0℃. Black iron pigment with high quality was obtained at the conditions of origimal pH 9.5,reaction temperature 85℃,reaction time 2.5h, stirring rate 150 r/min and drying temperature 80℃. XRD and SEM analysis showed that the particle size of the prepared black iron pigment was about 60nm,and Fe₃O₄ content was higher than 95%. The product could reach the requirements for the first-grade standard in black iron pigment industry. But in the black iron pigment, there was a little Cu₂O which made the product with some red color. Between the Fe₃O₄ particles, there was visible aggregation.After electrolyzed pyrite wastewater for 30min by 2.0V DC, black iron pigment with high tinting strength could be made through precipitation, wet oxidation and adding 0.75ml 1% citric acid at the beginning of reaction. XRD, SEM and color analysis showed that the high tinting strength black iron pigment had closer color to the standard sample and basicly with no red color in it. The agglomeration was obviously improved, the size of particle was in a little decrease.更多还原