权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Investigation of norsethite solubility as a fundamental contribution for a better understanding of the formation of Mg-containing carbonate minerals

菱长石溶解度的研究为更好地了解含镁碳酸盐矿物的形成做出了根本性贡献

基本信息

批准号：
263836853
负责人：
Professor Dr. Guntram Jordan
金额：
--
依托单位：
Arbeitsgebiet für anorganische und biogene Geomaterialien
依托单位国家：
德国
项目类别：
Research Grants
财政年份：
2014
资助国家：
德国
起止时间：
2013-12-31 至 2018-12-31
项目状态：
已结题

来源：
https://gepris.dfg.de/gepris/projekt/263836853?language=en
关键词：
Investigation norsethite solubility fundamental contribution

项目摘要

Dolomite [CaMg(CO3)2] is one of the most abundant carbonate minerals on Earth. The growth kinetics of dolomite at ambient temperature, however, is still not clear - laboratory syntheses in additive-free aqueous solutions fail generally. The reason for this failure is assumed to be the slow dehydration of Mg2+, which is also thought to be the reason for the growth problems of anhydrous Mg-carbonate minerals in general. Nevertheless, there is an anhydrous Mg-containing carbonate mineral which easily precipitates at room temperature from aqueous solution and which is structurally and chemically similar to dolomite: norsethite [BaMg(CO3)2]. In the BaCO3-MgCO3-system, norsethite is prevailing and occurs at variously different solution conditions and temperatures.As the solubility product of norsethite has only been determined experimentally at 25 °C, geochemical models of Ba2+ and Mg2+ containing waters at other temperatures are highly unreliable. Such models, however, are indispensable for any quantitative evaluation of mineral stability and growth kinetics at elevated temperatures. Accurate knowledge of the growth kinetics of magnesium containing minerals at elevated temperatures is of great significance (e.g., for an evaluation of the relevance of Mg-containing minerals in geological CO2 sequestration or for calculations of scale formation in industrial processes).Aim of the project, therefore, is to determine the solubility products of norsethite at various elevated temperatures (50-175 °C). These solubility products can make a significant and fundamental contribution to future carbonate mineral research. Furthermore, a comparison to the solubility product of dolomite can give valuable information to unravel the dolomite problem and to understand the easy formation of norsethite. Moreover, knowledge about norsethite growth allows a better assessment of the significance of the Mg2+ dehydration barrier during growth of Mg-containing carbonate minerals.

白云石[CaMg（CO 3）2]是地球上最丰富的碳酸盐矿物之一。然而，白云石在环境温度下的生长动力学仍然不清楚-在无添加剂的水溶液中的实验室合成通常失败。这种失败的原因被认为是Mg 2+的缓慢脱水，这也被认为是一般无水碳酸镁矿物生长问题的原因。然而，有一种无水的含镁碳酸盐矿物，在室温下很容易从水溶液中沉淀出来，并且在结构和化学上与白云石相似：norsethite [BaMg（CO 3）2]。在BaCO_3-MgCO_3-体系中，以北黄长石为主，其溶度积仅在25 °C时测定，其它温度下含Ba ~（2+）和Mg ~（2+）沃茨的地球化学模型不可靠。然而，这些模型是不可缺少的矿物稳定性和生长动力学在高温下的任何定量评价。含镁矿物在升高的温度下的生长动力学的准确知识具有重要意义（例如，因此，该项目的目的是确定东北锰矿在各种高温（50-175 °C）下的溶解度积。这些溶度积可以为未来碳酸盐矿物的研究做出重要的基础性贡献。此外，与白云石的溶度积的比较可以提供有价值的信息，以解开白云石的问题，并了解诺赛特的容易形成。此外，知识norsethite生长过程中的含镁碳酸盐矿物的生长过程中的Mg 2+脱水障碍的意义，可以更好地评估。

项目成果

期刊论文数量（4）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

On the growth of anhydrous Mg-bearing carbonates – Implications from norsethite growth kinetics

DOI：
10.1016/j.gca.2018.07.013
发表时间：
2018-10
期刊：
Geochimica et Cosmochimica Acta
影响因子：
5
作者：
M. Lindner;G. Saldi;Salvatore Carrocci;P. Bénézeth;J. Schott;Guntram Jordan
通讯作者：
M. Lindner;G. Saldi;Salvatore Carrocci;P. Bénézeth;J. Schott;Guntram Jordan

On the growth of witherite and its replacement by the Mg-bearing double carbonate norsethite: Implications for the dolomite problem