【作者】 张曦；

【导师】 李玉江； 齐涛；

【作者基本信息】 山东大学 ， 环境工程（专业学位）， 2020， 硕士

【摘要】 氧化铁颜料属于彩色无机颜料,其使用范围跨多个行业,氧化铁红是其中常用的一种。以化学合成制得的市售铁红具有纯度高、色泽较好等优点,但其生产工艺流程长、污染较严重、成本高。天然氧化铁红具有生产工艺简单、理化性能稳定且价格低廉的优点,是合成氧化铁红的理想替代品。由于矿石结构简单且晶体结构与氧化铁红一致,镜铁矿可被用作制备天然氧化铁红的材料。本课题旨在研发一种镜铁矿制备天然氧化铁红的新工艺。重点开展了镜铁矿的选矿提纯、精矿的超细磨粉碎、氧化铁红的表面改性三个方面的研究,为镜铁矿的高值化利用和铁红颜料的性能优化提供了一条新途径。主要工作如下:(1)系统研究了镜铁矿除杂提纯的规律。具体地,考察磨矿细度和磁场强度对磁选精矿品位和回收率的影响,分析药剂用量、pH等条件对阳离子反浮选的影响,并对比离心机重选用于镜铁矿精选的可行性,重点研究了给矿浓度、转速等条件的影响。研究结果表明,在磨矿细度-0.038 mm占93wt%,给矿浓度为5wt%,转鼓转速为600 r/min,漂洗水用量为2.15 L/min,漂洗时间为3 min时,经过两次离心重选可以实现镜铁矿的深度提纯,得到氧化铁纯度99.11wt%,回收率54.40%的高纯铁精矿。(2)系统研究了不同磨矿条件对镜铁矿粒度分布的影响,具体包括球磨时间、磨机转速、磨矿浓度、球磨罐的容积率等。结果表明,增加球磨时间和转速、保持适当的浓度和容积率,有利于减小粒度。超细磨样品的性能与铁红国际标准、市售铁红对比结果表明,其物化指标,包括水溶物、筛余物、吸油值等,显著优于市售。(3)查明了氧化铁红产品的色相调整机理。通过扫描电镜、XRD、紫外-可见分光光度法分析,发现一定时长的煅烧使得Fe2(S04)3转化为Fe203;不同的煅烧温度和硫酸质量分数通过影响粒度而改变光的反射、折射和吸收,从而调整色相;煅烧后,样品由不规则片状变成卵形结构。更多还原

【Abstract】 Iron oxide pigments are colored inorganic pigments,and their use ranges across multiple industries.Iron oxide red is one of the commonly used ones.The commercially available iron red has the largest dosage and is mostly chemically synthesized.It has the advantages of high purity and good color,but it has a long production process,serious pollution and high cost.The natural iron oxide red has the advantages of simple production process,stable physical,chemical properties and low price.It is an ideal substitute for synthetic iron oxide red.The specularite has a simple ore structure and the same crystal structure as iron oxide red,so it is a high-quality raw material for preparing natural iron oxide red.This subject aims to develop a new process for preparing natural iron oxide red from specularite.The research contents of beneficiation and purification of specularite,ultra-fine grinding of concentrate,and surface modification of iron oxide red were mainly carried out.It provides a new way for the high value utilization of specularite and the performance optimization of iron red pigment.Main tasks as follows:(1)The rule of impurity removal and purification of specularite was systematically studied.The effects of grinding size and magnetic field intensity on the grade and recovery rate of concentrates were investigated.The effects of the dosage of reagents,pH and other conditions on the reverse floatation of specularite were analyzed.The feasibility of specularite selection,focusing on the influence of conditions such as feed concentration and speed.The results show that at a grinding size of-0.038 mm,which accounts for 93wt%,the feed concentration is 5wt%,the drum speed is 600 r/min,the amount of rinsing water is 2.15 L/min,and the rinsing time is 3 min.The double centrifugation can realize the deep purification of the specularite,and obtain a high-purity iron concentrate with an iron oxide purity of 99.11wt%and a recovery rate of 54.40%.(2)The effects of different grinding conditions on the particle size distribution of specularite were systematically studied,including ball milling time,mill speed,grinding concentration,and volume ratio of ball milling tanks.The results show that increasing the time and rotational speed,maintaining an appropriate concentration and volume ratio are beneficial to reduce the particle size.After comparison with the international standard of iron red and commercially available iron red,the physical and chemical indicators have reached the requirements,and the oil absorption value,matter soluble in water,and residue on sieve are better than those on the market.(3)The hue adjustment mechanism of iron oxide red products was investigated.Scanning electron microscopy,XRD,and UV-visible spectrophotometric analysis revealed that calcination for a certain period of time caused Fe2(SO4)3 to be converted to Fe2O3;Different calcination temperatures and sulfuric acid mass fractions change the reflection,refraction and absorption of light by affecting the particle size,thereby adjusting the hue;After calcination,the sample changed from irregular flake to oval structure.更多还原