Microwave Roasting-acid-base Combined Leaching Of High-titanium Slag

Titanium dioxide its physical and chemical properties are stable,with high refractive index,hiding power,strong coloring,anti-powder and other excellent optical and electrical properties.So it is widely used in papermaking,plastics,paint,ink,enamel,electrical,metallurgical,chemical industry and other fields.At present,the titanium dioxide industrial production methods are mainly two categories:First,sulfuric acid production and chlorination production.Rutile is an important raw material for the production of titanium dioxide.With the continuous development of titanium industry,the supply of natural rutile has been gradually reduced,and artificial rutile in performance and other aspects of natural rutile similar to natural rutile can be used as a substitute for quality.Therefore,the continuous exploration of the new process of producing synthetic rutile has become a trend that can not be ignored in the development of titanium industry.In this paper,taking Yunnan high titanium slag as raw material,combined with microwave heating technology,a new technology of microwave processing of high titanium slag which is "high titanium slag-alkaline leaching-microwave roasting-acid leaching-calcinations" proposed.Microwave heating technology is a new metallurgical technology developed in recent years.As a kind of clean energy for heating technology,microwave has the advantages of selective heating,uniform heating,high thermal conversion efficiency and overall heating.In the present study,the modern analysis and testing technology like chemical composition analysis,X-ray diffraction analysis,TG-DSC analysis,SEM-EDS analysis,Raman spectrum analysis,FT-IR spectrum analysis and X-ray photoelectron spectroscopyanalysis were used to investigated the chemical composition,particle size composition,temperature rise characteristics,phase structure,apparent morphology and composition for raw materials and the product that obtained by the process of "high titanium slag-alkaline leaching-microwave roasting-acid leaching-calcinations".And through the study of the relevant principles of the process and expolied the best process parameters,obtained the specific experimental operating conditions are:alkaline leaching conditions are:temperature at 94'C,alkaline concentration 80 g/L,liquid to solid ratio 6:1,operating time is 60 min;microwave roasting conditions are:temperature at 850?,time is 120 min,mass ratio of 0.25;acid leaching conditions are:temperature at 94?,sulfuric acid concentration 30%,time is 4 h;calcination conditions are:temperature at 950?,operating time is 30 min.At this condition can obtain high quality artificial rutile.The high titanium slag was used reasonably in this study,and the "high-titanium slag-alkaline leaching-microwave roasting-acid leaching-calcination" process was put forward and obtained good results,for the depth of the development and rational use of titanium resources to provide a new way.