首页 | 本学科首页   官方微博 | 高级检索  
     检索      

从矿物粉晶表面反应性到矿物晶面反应性——以黄铁矿氧化行为的晶面差异性为例
引用本文:何宏平,鲜海洋,朱建喜,谭伟,梁晓亮,陈锰.从矿物粉晶表面反应性到矿物晶面反应性——以黄铁矿氧化行为的晶面差异性为例[J].岩石学报,2019,35(1):129-136.
作者姓名:何宏平  鲜海洋  朱建喜  谭伟  梁晓亮  陈锰
作者单位:中国科学院矿物学与成矿学重点实验室, 中国科学院广州地球化学研究所, 广州 510640;广东省矿物物理与材料研究开发重点实验室, 中国科学院广州地球化学研究所, 广州 510640;中国科学院大学, 北京 100049,中国科学院矿物学与成矿学重点实验室, 中国科学院广州地球化学研究所, 广州 510640;广东省矿物物理与材料研究开发重点实验室, 中国科学院广州地球化学研究所, 广州 510640,中国科学院矿物学与成矿学重点实验室, 中国科学院广州地球化学研究所, 广州 510640;广东省矿物物理与材料研究开发重点实验室, 中国科学院广州地球化学研究所, 广州 510640,中国科学院矿物学与成矿学重点实验室, 中国科学院广州地球化学研究所, 广州 510640;广东省矿物物理与材料研究开发重点实验室, 中国科学院广州地球化学研究所, 广州 510640,中国科学院矿物学与成矿学重点实验室, 中国科学院广州地球化学研究所, 广州 510640;广东省矿物物理与材料研究开发重点实验室, 中国科学院广州地球化学研究所, 广州 510640,中国科学院矿物学与成矿学重点实验室, 中国科学院广州地球化学研究所, 广州 510640;广东省矿物物理与材料研究开发重点实验室, 中国科学院广州地球化学研究所, 广州 510640
基金项目:本文受国家自然科学基金项目(41573112)和国家外专局"创新国际团队项目"(20140491534)联合资助.
摘    要:地球系统中各种矿物相的物理化学反应大多是从矿物表面或界面开始的。要揭示矿物表面反应性的本质,就需要从控制其反应性的表面结构入手。由于实验条件的限制,绝大多数关于矿物表面物理化学性质的研究主要采用粉晶作为研究对象。尽管粉晶方法在研究诸如硅酸盐、碳酸盐溶解和沉淀结晶等过程中被普遍采用,但这种基于矿物粉晶的研究方法还是有一定的不足。因为形成粉晶的破碎研磨过程会导致晶体高能面的出现,高能面所具有的高活性可能会加速其反应过程,应用于地球化学反应的计算结果就可能高估了实际的地球化学反应速率。本研究以黄铁矿表面氧化反应的晶面差异性为例,从晶面结构制约反应性的角度出发,重新审视了黄铁矿氧化的相关问题,弥补了传统"粉晶研究"中对黄铁矿氧化速率和氧化机理认识的缺陷。黄铁矿宽范围的氧化速率实测值很可能是由不同晶面间较大的反应性差异导致;水在黄铁矿的氧化过程中同时扮演着传递电子的催化剂和反应物的角色,也是黄铁矿氧化反应速控步(rate-limiting step)的核心物质。这些认识首次明确了黄铁矿不同晶面反应性差异的重要性,并提示我们应将传统表面矿物学的研究推向更为精确的晶面矿物学水平。这一从晶面角度考察发生在矿物表面的地球化学反应的研究方法可为构建更为精确的地球化学模型提供理论基础。

关 键 词:黄铁矿  晶面  反应性  氧化速率  氧化机理
收稿时间:2018/9/8 0:00:00
修稿时间:2018/11/13 0:00:00

Perspective of mineral reactivity from surfaces to crystal faces: A case study on the oxidation behavior differences among various crystal faces of pyrite
HE HongPing,XIAN HaiYang,ZHU JianXi,TAN Wei,LIANG XiaoLiang and CHEN Meng.Perspective of mineral reactivity from surfaces to crystal faces: A case study on the oxidation behavior differences among various crystal faces of pyrite[J].Acta Petrologica Sinica,2019,35(1):129-136.
Authors:HE HongPing  XIAN HaiYang  ZHU JianXi  TAN Wei  LIANG XiaoLiang and CHEN Meng
Institution:CAS Key Laboratory of Mineralogy and Metallogeny, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China;Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China;University of Chinese Academy of Sciences, Beijing 100049, China,CAS Key Laboratory of Mineralogy and Metallogeny, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China;Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China,CAS Key Laboratory of Mineralogy and Metallogeny, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China;Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China,CAS Key Laboratory of Mineralogy and Metallogeny, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China;Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China,CAS Key Laboratory of Mineralogy and Metallogeny, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China;Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China and CAS Key Laboratory of Mineralogy and Metallogeny, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China;Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
Abstract:Almost all geochemical reactions occurring in the Earth system start at mineral surfaces or mineral-water interfaces. To reveal the nature of surface reactivity, the surface structure of minerals needs to be investigated, which control their surface reactivity. However, due to the limitation of experimental techniques, most studies on the physical and chemical properties of mineral surfaces were mainly carried out by using mineral powders as studying materials. Despite that the using of mineral powder is widely accepted in many case studies, such as the dissolution and precipitation of silicate and carbonate minerals, such methods based on mineral powder still have certain deficiencies for the investigation of mineral surface reactivity. Surfaces with high energy, which can enhance their surface reactivity, will be produced during sample preparation by crushing or grinding. Thus, the obtained experimental results may lead to an overestimation of geochemical reaction in comparison to real situations. Based on the perspective of structure dependent surface reactivity, this study makes up the lack for understanding the rate and mechanism of pyrite oxidation and provides new insights into the oxidation mechanism. Our study demonstrates that the wide range of pyrite oxidation rates reported in literatures is resulted from the prominent surface reactivity differences among different crystal faces. In these reaction systems, water molecules act as both reactant and catalyst for electron transfer in the oxidation process and also is the core substance in the reactions. These understandings have clarified the importance of the surface reactivity differences among different crystal faces. The present study suggests that, to reveal the real geochemical processes, we should focus on the reactivity of certain crystal faces with high accuracy rather than of traditionally concerned powder surfaces. Such approaches, based on the perspective of crystal face reactivity, could provide fundamental knowledge for constructing accurate geochemical models.
Keywords:Pyrite  Crystal face  Reactivity  Oxidation rate  Oxidation mechanism
本文献已被 CNKI 等数据库收录!
点击此处可从《岩石学报》浏览原始摘要信息
点击此处可从《岩石学报》下载免费的PDF全文
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号