An unusual isotopic fractionation of boron in synthetic calcium carbonate precipitated from seawater and saline water

ISL OpenIR > 青海盐湖研究所知识仓储

	An unusual isotopic fractionation of boron in synthetic calcium carbonate precipitated from seawater and saline water
	Xiao Yingkai ; Li Shizhen ; Wei Haizhen ; Sun Aide ; Zhou Weijian ; Liu Weiguo
	2006-10-01
发表期刊	SCIENCE IN CHINA SERIES B-CHEMISTRY
卷号	49 期号:5 页码:454-465
关键词	Boron Isotopic Fractionation Calcium Carbonate Precipitate Seawater Saline Water
摘要	Inorganic calcium carbonate precipitation from natural seawater and saline water at various pH values was carried out experimentally. The results show the clear positive relationships between boron concentration and delta B-11 of inorganic calcium carbonate with the pH of natural seawater and saline water. However, the variations of boron isotopic fractionation between inorganic calcite and seawater/saline water with pH are inconsistent with the hypothesis that B(OH)(4)(-) is the dominant species incorporated into the biogenic calcite structure. The isotopic fractionation factors a between synthetic calcium carbonate precipitate and parent solutions increase systematically as pH increases, from 0.9884 at pH 7.60 to 1.0072 at pH 8.60 for seawater and from 0.9826 at pH 7.60 to 1.0178 at pH 8.75 for saline water. An unusual boron isotopic fractionation factor of larger than 1 in synthetic calcium carbonate precipitated from seawater/saline water at higher pH is observed, which implies that a substantial amount of the isotopically heavier B(OH)(3) species must be incorporated preferentially into synthetic inorganic carbonate. The results propose that the incorporation of B(OH)(3) is attributed to the formation of Mg(OH)(2) at higher pH of calcifying microenvironment during the synthetic calcium carbonate precipitation. The preliminary experiment of Mg(OH)(2) precipitated from artificial seawater shows that heavier B-11 is enriched in Mg(OH)(2) precipitation, which suggests that isotopically heavier B(OH)(3) species incorporated preferentially into Mg(OH)(2) precipitation.
语种	英语
引用统计
文献类型	期刊论文
条目标识符	http://ir.isl.ac.cn/handle/363002/5762
专题	青海盐湖研究所知识仓储中国科学院青海盐湖研究所
作者单位	1.Chinese Acad Sci, Qinghai Inst Salt Lakes, Xining 810008, Peoples R China 2.Chinese Acad Sci, Inst Earth Environm, State Key Lab Loess & Quaternary Geol, Xian 710075, Peoples R China
推荐引用方式 GB/T 7714	Xiao Yingkai,Li Shizhen,Wei Haizhen,et al. An unusual isotopic fractionation of boron in synthetic calcium carbonate precipitated from seawater and saline water[J]. SCIENCE IN CHINA SERIES B-CHEMISTRY,2006,49(5):454-465.
APA	Xiao Yingkai,Li Shizhen,Wei Haizhen,Sun Aide,Zhou Weijian,&Liu Weiguo.(2006).An unusual isotopic fractionation of boron in synthetic calcium carbonate precipitated from seawater and saline water.SCIENCE IN CHINA SERIES B-CHEMISTRY,49(5),454-465.
MLA	Xiao Yingkai,et al."An unusual isotopic fractionation of boron in synthetic calcium carbonate precipitated from seawater and saline water".SCIENCE IN CHINA SERIES B-CHEMISTRY 49.5(2006):454-465.