低品位氧化锰矿与电解锰结晶复盐低温熔盐协同处理回收锰、镁以及铵/氨基础研究

低品位氧化锰矿和电解锰结晶复盐 (简称结晶复盐) 作为电解金属锰行业重要的固体废弃物，采用堆存的方式处理，不仅占用大量土地，造成严重的环境污染，而且导致锰、镁以及铵/氨资源的严重浪费。针对这一现状，申请人在前期研究和调研的基础上，利用铵类低温熔盐对Mn高价氧化物的还原特性，提出了低品位氧化锰与结晶复盐低温熔盐协同处理回收Mn、Mg以及NH4+/NH3的技术方案。本项目拟对该方案的可行性开展基础研究，阐明低温熔盐反应过程中各组分的物相转化行为，明确协同处理的热力学和动力学特征，揭示低温熔盐还原机理，建立物相转化调控方式。以低温熔盐处理-水浸所得水溶液为基础，建立硫酸盐水溶液热力学体系，明确该体系中各元素沉淀分离的有效区间，选择性沉淀分离、回收Mn、Mg以及NH4+/NH3。该项目的有效开展，对于缓解我国锰矿资源紧缺，消除低品位氧化锰矿与结晶复盐造成的环境污染和资源浪费具有重要指导作用。

Both low-grade manganese oxide ore (LGMOO) and complex sulfate salts crystallised from the production process of electrolytic manganese metal (referred to as crystallised complex sulfate salts, CCSS) are important solid wastes in the electrolytic manganese metal industry. The disposal of them by stockpiling not only consumes considerable areas of land and results in significant environmental pollution, but also leads to a serious waste of manganese, magnesium and ammonium/ammonia resources. In order to solve this problem, on the basis of previous research and investigation, a new technical scheme is proposed for co-treatment of LGMOO and CCSS to recover Mn, Mg, and NH4+/NH3, according to the reduction properties of low-temperature molten salts with ammonium to high valence manganese oxides. In this project, the basic research on the feasibility of this scheme will be carried out, including to clarify the phase transformation behavior of each component during the low-temperature molten salt reaction, determine the thermodynamic and kinetic characteristics of the co-treatment, reveal the reduction mechanism of the low-temperature molten salt clarify the phase transformation, and establish the control method of the phase transformation. Based on the solution obtained from water leaching after low-temperature molten salt treatment, some thermodynamic systems of solutions will be established to define the effective interval of precipitation and separation of various elements in the systems, and finally the Mn, Mg, and NH4+/NH3 will be selectively precipitated and recovered. Those results obtained in this project will provide an important guidance to alleviate the resources shortage of manganese ore in our country, and eliminate the environmental pollution and resource waste caused by LGMOO and CCSS.