环保Fe12SrO19铁氧体磁粉制备

Preparation of green strontium ferrite magnetic powders

针对电机用铁氧体（主要成分有Fe2O3，SrCO3，添加剂有SrC12，SiO2，SrSO4，CaCO3，A12O3，Cr2O3）中Cr^6＋含量较高，采用高温氩气还原反应法，分250～780～1150123个温度段还原，每个温度段恒温10min。利用二苯碳酰二肼（C13H14N4O）分光光度法检测其Cr^6＋含量，利用能谱分析其成分及含量对比变化，X射线衍射对比分析反应前后主要成分变化趋势。结果显示铁氧体中Cr^6＋含量由2×10^-4左右降至5×100^-5以下，其主要成分改变量较小，指标达到欧盟实施的（《电器、电子设备中限制使用某些有害物质指令》（the restriction of the use of certain hazardous substances in electrical and electronic equipment,简称RoHS）环保条款要求．

For the ferdte （the main ingredients are Fe2O3 and SrCO3, additives are SrCl2, SiO2, SrSO4, CaCO3, A12O3 and Cr2O3） used in motor contains higher content of Cr^6＋, the high-temperature argon-gas reduction method was used to reduce it in the paper, and the reduced temperature could be controlled from 250 to 780℃ and then to 1150℃. At every point of temperature above, heating was continued for 10rain respectively. The content of Cr^6＋ was detected with the dipehenylcarbohydrazide （C13H14N4O） spectrophotometry, and its changed content was inverstigated by means of SEM and XRD measurements. The results indicate that the content of Cr was reduced from about 2×10^-4 to 5×100^-5 below, and the change of major ingredients is slight. Also the contend is up to the mustard of the RollS executed by the European Union.