The Research On Preparing High Pure Iron Oxide Red Pigment From Pyrite Cinder

The pyrite cinder is the industrial solid waste. The comprehensive utilization can not only recover the source but also control the cinders pollution. The iron oxide red have been made from sulfate, which is prepare from the cinders. The new process of the cinders comprehensive utilization has been developed.Based on a detailed investigation of present utilization and recovery of pyrite cinder, compared with the producing methods of iron oxide red, according to the real experiment condition, the iron oxide red have been made by calcined the iron salt.The whole experiment process was divided into four parts: the first is reduction roasting of pyrite cinder. The effect of roasting temperature, roasting time and the reducer dosage on the leaching ratio has been studied. The best process condition is cinder/ lignite is 1/0.8(wt), the roasting temperature is 800, the roasting time is 20min. The second is vitriol lixiviate. The effect of vitriol excess coefficient, reaction temperature and reaction time on the leaching ratio has been studied. When the vitriol excess coefficient is 1.2, reaction temperature is 70 , reaction time is 20min, the leaching rate is 99% under the above reaction factors. The third is the compounding of NH4HCO3. The effect of NH4+/Fe2+mol ratio, FeSO4 concentration, reaction temperature and reaction time on the conversion ratio of Fe2+ has been discussed. When the NH4+/Fe2+mol ratio is 3.5, FeSO4 concentration is 0.8~1.0mol/l, reaction temperature is 40 , reaction time is 30min, the conversion ratio of Fe2+ to Fe3+ is 99%. The FeCO3 is desiccated three hours on the temperature of 70~80 , then to be calcined one hour on the temperature of 800 , the iron oxide red can be obtained which the purity is 94.5%. The quality examination showed that the quality indexes achieved the standard of GB1863-89.The XRD was applied in the study to explore the effect of calcinations temperature and time on the product crystal. XRD discovered the product crystal is a - Fe2O3 SEM proved that the product is incompact before calcinations, but it become compact after being calcined, and it has plenty of symmetrical, exiguous holes. The granule is global, and the average size is 1.0 m .The utilization of preparing iron oxide red by pyrite cinder, which can not only control the cinders pollution but also can supply the new technology and new material. It has preferable social, economic and environmental benefits.