【摘要】 利用石灰的加碳还原反应,设计了一个新的研究方法,以直接测定液态高炉型渣中CaO的活度.这一方法的成功,依靠溶剂金属的正确选择以降低熔液中钙的化学位,而使金属钙量提高到可以用化学分析测定的水平.我们估计钙在锡稀溶液中的活度系数很小,可能符合于我们的要求,因此研究了下列反应:CaO+C（石墨）=Ca（锡）+CO（气）.以测定液态CaO-SiO₂和CaO-Al₂O₃-SiO₂渣中CaO的活度,在上式中符号下波纹线表示溶于渣中的组分,直线表示溶子金属中的组分,下同.对于CaO-Si0₂系,应用Gibbs-Duhem关系从CaO活度值算出了SiO₂的活度值,并根据一个统计力学模型讨论了活度曲线的形状.从CaO-Al₂O₃-SiO₂系的研究结果,可知在所研究的整个碱度范围內,渣中存在10%Al₂O₃都使CaO的活度增加;当Al₂O₃为20%时,则对CaO活度的影响视碱度不同而异.对Al₂O₃的这种行为,根据炉渣的离子结构理论提出了解释.更多还原

【Abstract】 A new method,based on the carbothermic reduction of lime,has been devised forthe direct determination of the activity of lime in liquid blast-furnace-type slags.Thesuccess of the method depends upon the proper choice of the solvent metal to lower thechemical potential of calcium in the melt.Owing to the expected very small activity co-efficient of calcium in dilute solutions in tin,the reactionCaO（in slags）+C=Ca（in tin）+CO.has been studied with a view to evaluating activities of lime in liquid CaO-SiO₂ andCaO-Al₂O₃-SiO₂ slags.The activity values in the CaO-SiO₂ system have been used toderive silica activities through the Gibbs-Duhem relationship.The shape of the activitycurves is briefly discussed on the basis of a statistical mechanical model.It has been found from the results on the ternary system that the activity of lime isincreased by the presence of 10% alumina in the slags for the entire basicity range underinvestigation.An explanation based on the ionic constitution of slags is offered for thisbehaviour of alumina.更多还原