11 research outputs found
Research of characterization of zinc ferrite, titanium dioxide and their composites
In this paper, zinc calcines, sulfuric acid, ferric nitrate nine-hydrate, zinc nitrate hexahydrate, titanium oxide sulfate, sodium hydroxide and ammonia water were selected as raw materials, and the methods of sulfuric acid leaching and chemical coprecipitation were used to prepare purified zinc ferrite, synthetic zinc ferrite, synthetic titanium dioxide and its composite with purified zinc ferrite. And characterized by BET, UVVis and FTIR. The results showed that: SO42- existed in purified zinc ferrite. Purified zinc ferrite, synthetic zinc ferrite and purchased had different specific surface area, pore volume and average pore size. The specific surface area of synthetic zinc ferrite decreased with the increase of calcination temperature. The three kinds of zinc ferrite had good absorption of ultraviolet light and visible light. Purchased ferric acid had the strongest absorption of UV light and synthetic zinc ferrite had the strongest absorption of visible light, and purified zinc ferrite had the absorption of UV light and visible light between the two. The specific surface area of titanium dioxide prepared by chemical coprecipitation method was greatly affected by calcination temperature. With the increase of calcination temperature, the specific surface area decreased from 123.633 to 28.036m2·g-1, and the average pore diameter was less affected by calcination temperature. For the zinc ferrite/titanium dioxide composite prepared by chemical coprecipitation method, a certain amount of purified zinc ferrite was added to facilitate the absorption of visible light by titanium dioxide
Study on properties of zinc ferrite, titanium dioxide and their composites
In this paper, the methods of sulfuric acid leaching and chemical coprecipitation were used to prepare products such as purified zinc ferrite, synthetic zinc ferrite, synthetic titanium dioxide and its complex with purified zinc ferrite. The morphology and microstructure of the above samples were characterized and analyzed by XRD and SEM. The results showed that the purified zinc ferrite contained a small amount of ZnO, SiO2, Al2O3 and PbSO4. Its particle size was the largest and the crystallinity was the best, but the surface was not smooth, the particle size distribution was not uniform and there was agglomeration phenomenon. The purchased zinc ferrite had high purity, the smallest particle size and the worst crystallinity. Its surface was smooth, particle size distribution was uniform, and it was loose and porous. The synthetic zinc ferrite had high purity, smooth surface, uniform particle size distribution and obvious agglomeration. The prepared titanium dioxide had no other impurities, good crystallinity, smooth surface and certain agglomeration phenomenon. For the zinc ferrite/titanium dioxide composite, adding a small amount of purified zinc ferrite would change the crystallinity of titanium dioxide, but it had little effect on the grain size of titanium dioxide. The surface was rough, the particle size distribution was not uniform, and there was agglomeration phenomenon
Study on Hydrometallurgical Treatment of Oxide Ores Bearing Zinc
As the depletion of zinc sulfide ores becomes more severe, investigations into the recovery of zinc from zinc oxide ores have aroused more interest. In this regard, acid-based hydrometallurgical treatment strategies have had great effectiveness. However, they are inadequate for low-grade zinc oxide ores. In this study, we examined the alkaline treatment of gossan for the recovery of oxide ores that bear zinc, such as siderite and limonite. Additionally, of particular note, the effects of a leaching agent, its concentration and time, temperature, liquid-to-solid ratio, as well as the agitation rate on the leaching of zinc from gossan were studied to evaluate the effects of these parameters on the kinetics of zinc dissolution. The results showed that the leaching of zinc is controlled by a single rate-controlling step with an activation energy of 4.458 kJ/mol before 120 min and 5.536 kJ/mol after 120 min, with zinc leaching efficiency less than 50% in all leachings
Study on properties of zinc ferrite, titanium dioxide and their composites
In this paper, the methods of sulfuric acid leaching and chemical coprecipitation were used to prepare products such as purified zinc ferrite, synthetic zinc ferrite, synthetic titanium dioxide and its complex with purified zinc ferrite. The morphology and microstructure of the above samples were characterized and analyzed by XRD and SEM. The results showed that the purified zinc ferrite contained a small amount of ZnO, SiO2, Al2O3 and PbSO4. Its particle size was the largest and the crystallinity was the best, but the surface was not smooth, the particle size distribution was not uniform and there was agglomeration phenomenon. The purchased zinc ferrite had high purity, the smallest particle size and the worst crystallinity. Its surface was smooth, particle size distribution was uniform, and it was loose and porous. The synthetic zinc ferrite had high purity, smooth surface, uniform particle size distribution and obvious agglomeration. The prepared titanium dioxide had no other impurities, good crystallinity, smooth surface and certain agglomeration phenomenon. For the zinc ferrite/titanium dioxide composite, adding a small amount of purified zinc ferrite would change the crystallinity of titanium dioxide, but it had little effect on the grain size of titanium dioxide. The surface was rough, the particle size distribution was not uniform, and there was agglomeration phenomenon
Study on preparation and properties of zinc ferrite and titanium dioxide
In this paper, sulfuric acid leaching high iron zinc calcine was used to prepare and purify zinc ferrite, high temperature roasting method was used to prepare synthetic zinc ferrite, and sol-gel method was used to prepare TiO2. The properties of the prepared samples ware characterized by XRD, FT-IR, BET, SEM and other methods. The results show that the synthetic zinc ferrite is pure zinc ferrite, and the purified zinc ferrite contains impurities PbSO4. The TiO2 crystal form prepares at the calcination temperature of 300~550°C is basically the same, and the crystal form transformation occurs at the calcination temperature of 550~600°C. TiO2 samples calcines at 400°C (T400) have higher specific surface area, larger total pore volume and average pore diameter. The crystalline degree of synthetic zinc ferrite is high, the micropores on the crystal surface are closed, and the grains bond with each other. The specific surface area, total pore volume and average pore diameter of purified zinc ferrite are larger than those of synthetic zinc ferrite. The effects of specific surface area, pore volume and pore structure on the adsorption capacity and catalytic efficiency are as follows: T400> purified zinc ferrite > synthesized zinc ferrite
Research of characterization of zinc ferrite, titanium dioxide and their composites
In this paper, zinc calcines, sulfuric acid, ferric nitrate nine-hydrate, zinc nitrate hexahydrate, titanium oxide sulfate, sodium hydroxide and ammonia water were selected as raw materials, and the methods of sulfuric acid leaching and chemical coprecipitation were used to prepare purified zinc ferrite, synthetic zinc ferrite, synthetic titanium dioxide and its composite with purified zinc ferrite. And characterized by BET, UVVis and FTIR. The results showed that: SO42- existed in purified zinc ferrite. Purified zinc ferrite, synthetic zinc ferrite and purchased had different specific surface area, pore volume and average pore size. The specific surface area of synthetic zinc ferrite decreased with the increase of calcination temperature. The three kinds of zinc ferrite had good absorption of ultraviolet light and visible light. Purchased ferric acid had the strongest absorption of UV light and synthetic zinc ferrite had the strongest absorption of visible light, and purified zinc ferrite had the absorption of UV light and visible light between the two. The specific surface area of titanium dioxide prepared by chemical coprecipitation method was greatly affected by calcination temperature. With the increase of calcination temperature, the specific surface area decreased from 123.633 to 28.036m2·g-1, and the average pore diameter was less affected by calcination temperature. For the zinc ferrite/titanium dioxide composite prepared by chemical coprecipitation method, a certain amount of purified zinc ferrite was added to facilitate the absorption of visible light by titanium dioxide
Study on Hydrometallurgical Treatment of Oxide Ores Bearing Zinc
As the depletion of zinc sulfide ores becomes more severe, investigations into the recovery of zinc from zinc oxide ores have aroused more interest. In this regard, acid-based hydrometallurgical treatment strategies have had great effectiveness. However, they are inadequate for low-grade zinc oxide ores. In this study, we examined the alkaline treatment of gossan for the recovery of oxide ores that bear zinc, such as siderite and limonite. Additionally, of particular note, the effects of a leaching agent, its concentration and time, temperature, liquid-to-solid ratio, as well as the agitation rate on the leaching of zinc from gossan were studied to evaluate the effects of these parameters on the kinetics of zinc dissolution. The results showed that the leaching of zinc is controlled by a single rate-controlling step with an activation energy of 4.458 kJ/mol before 120 min and 5.536 kJ/mol after 120 min, with zinc leaching efficiency less than 50% in all leachings
Study on preparation and properties of zinc ferrite and titanium dioxide
In this paper, sulfuric acid leaching high iron zinc calcine was used to prepare and purify zinc ferrite, high temperature roasting method was used to prepare synthetic zinc ferrite, and sol-gel method was used to prepare TiO2. The properties of the prepared samples ware characterized by XRD, FT-IR, BET, SEM and other methods. The results show that the synthetic zinc ferrite is pure zinc ferrite, and the purified zinc ferrite contains impurities PbSO4. The TiO2 crystal form prepares at the calcination temperature of 300~550°C is basically the same, and the crystal form transformation occurs at the calcination temperature of 550~600°C. TiO2 samples calcines at 400°C (T400) have higher specific surface area, larger total pore volume and average pore diameter. The crystalline degree of synthetic zinc ferrite is high, the micropores on the crystal surface are closed, and the grains bond with each other. The specific surface area, total pore volume and average pore diameter of purified zinc ferrite are larger than those of synthetic zinc ferrite. The effects of specific surface area, pore volume and pore structure on the adsorption capacity and catalytic efficiency are as follows: T400> purified zinc ferrite > synthesized zinc ferrite
Study on Adsorption and Photocatalytic Properties of Zinc Ferrite
In this study, methyl orange, methylene blue, and amido black 10B were removed as target dyes using purified, synthetic, and purchased zinc ferrite as adsorbents and photocatalysts. The highest removal rates of amido black 10B by these adsorbents ranged from 81.62% to 88.33%. The removal rate of methyl orange was approximately 1%, and the removal rate of methylene blue was approximately 2%. Hence, an investigation was conducted to elucidate the factors that influence the removal efficacy of purified zinc ferrite on amido black 10B. Titanium dioxide prepared at different calcination temperatures was unsuccessful in removing amido black 10B, but the physical mixing of titanium dioxide prepared at suitable calcination temperatures with purified zinc ferrite had a positive effect on amido black 10B removal. Since zinc ferrite could not be used as an adsorbent to remove methyl orange and methylene blue, the photocatalytic degradation properties of zinc ferrite and its influencing factors were studied. The optimal conditions for the photocatalytic degradation of methylene blue and methyl orange by zinc ferrite are as follows: a zinc ferrite catalyst dosage of 0.15 g, an initial solution concentration of 20 mg/L, and a pH of 6.0. The dosage of the zinc ferrite/titanium dioxide composite catalyst is 0.15 g, the initial solution concentration is 20 mg/L, and the pH is 6.5
Research on the Relationship between Multi-Component Complex Ore and Its Component Minerals’ Grinding Characteristics under Abrasion Force
The relationship between the grinding characteristics of polymetallic complex ore and its component minerals, pyrrhotite, sphalerite, and quartz, under the action of abrasion was studied, based on batch grinding experiments and theoretical analysis methods of selective grinding. The results show that when the polymetallic complex ore was subjected to the action of abrasion, the crushing effect of ore was enhanced by the existence of sphalerite, that is, sphalerite plays a positive role in the crushing effect of ore. The crushing effect of ore was reduced by the existence of pyrrhotite and quartz, that is, pyrrhotite and quartz plays a negative role in the crushing effect of ore. In addition, the sphalerite had a more prominent effect on the grinding characteristics of the ore. The grinding speed of ore and its component minerals decreased exponentially with the grinding time, and the instantaneous grinding speed of 0 min was negatively correlated with the feed sizes. The rapidly decreasing trend of the grinding speed reached the threshold when the grinding time reached 4 min. The results can provide some theoretical guidance for the study of grinding characteristics of multi-component complex ores in subsequent grinding process