不同实验条件对锰矿法制备介孔纳米四氧化三锰性能的影响

采用简单易行,成本低廉的锰矿法,以软锰矿焙烧熟料溶出液为原料,氨水为沉淀剂,空气为氧化剂,制备四氧化三锰。研究了不同实验条件对Mn_3O_4物相、形貌、比表面积的影响,采用XRD、SEM和BET对产物进行表征。结果表明,不同的实验条件对所得产物物相组成没有明显影响,经过超声处理的样品结晶度更好;不同的实验条件所得产物均为介孔结构的纳米级四氧化三锰,但对产物形貌和比表面积有较大影响。实验最佳条件为:不经过超声,未加任何添加剂,Mn_SO_4反加到NH_3·H_2O中的沉淀-氧化两步法。所得产物由球状颗粒和细棒状组成,球状颗粒的粒径最小,大部分小于50 nm,比表面积为35. 05 m^2/g。

Effect of Different Experimental Conditions on the Performance of Mesoporous Nano-Mn3 O4 Prepared by a Manganese Ore Method

Using leaching solution of pyrolusite sulfuric acid roasting clinker as raw material, aqueous ammonia as precipitant, and air as oxidant, Mn 3O 4 was prepared by the simple and economically feasible manganese ore method. The effects of different experimental conditions on the phase, morphology and specific surface area of Mn 3O 4 were studied, the products were characterized by X-ray diffraction, scanning electron microscope, and Brunauer-Emmett-Teller surface area analyzer. The results show that the products obtained under different experimental conditions are high purity Mn 3O 4, and the crystallinity of the samples with ultrasonic treatment is better. The products obtained are Nano Mn 3O 4 with mesoporous structure, however, the change of experimental conditions affects the morphology and specific surface area of the product. The optimum condition for preparation of Mn 3O 4 area precipitation-oxidation route,in which MnSO 4 is added to NH 3·H 2O without ultrasound and any additives. The morphology is the mixture of nanorods and small particles, the size of the spherical particles are less than 50 nm, and the specific surface area reaches 35.05 m 2/g.