一步烧结法合成镁铝尖晶石的研究与工业应用

Research and industrial application of synthesized MgAl_2O_4 by one step sintering method

以特级铝矾土生料、轻烧氧化镁粉等为原料,纸浆废液为结合剂,在1600℃煅烧3h,研究了活性Al2O3微粉、镁铝尖晶石粉、硼酸(H3BO3)、MgCl2.6H2O等对合成镁铝尖晶石体积密度的影响。结果表明,添加硼酸能有效提高合成尖晶石的体积密度,而且对工业生产成本增加有限,本试验的最佳加入量(质量分数)为1.5%。在不改变基本原料和工艺参数的情况下进行了工业试验,即将质量分数为1.5%的硼酸与矾土生料和轻烧镁粉共磨,然后加入适量纸浆废液混练并压球成型,干燥后在回转窑中于1700℃煅烧。结果表明,在矾土基合成镁铝尖晶石的生产工艺中,添加少量硼酸能促进合成尖晶石的烧结,提高合成尖晶石的体积密度和产品回收率,具有一定的应用价值。

MgAl2O4 was synthesized with top grade raw bauxite and light burned magnesia powder as main starting materials, paper pulp waste liquid as binder, and firing at 1 600 ℃ for 3 h. Effects of active Al2O3 micropowder, MgAl2O4 powder, H3BO3, MgCl2 · 6H2O on bulk density of the synthesized MgAl2O4 were researched. The results show that adding H3BO3 can effectively increase bulk density of synthesized MgAl2O4 with limited industrial production cost＇s increase, and its optimum addition is 1. 5%. Industrial test was carried out without changing the basic starting materials and process parameters, that is milling 1. 5% H3BO3 with raw bauxite powder and light burned magnesia powder, adding appropriate paper pulp waste liquid, mixing, palletizing molding, drying and firing at 1 700 ℃ in rotary kiln. The results show that, During the synthesizing of bauxite based MgAl2O4, adding small amount H3BO3 can promote the sintering of synthesized MgAl2O4, increase bulk density and product recovery rate, and has certain application value.