干旱区生态环境知识资源中心(Arid): Effects of carbonate on ferrihydrite transformation in alkaline media

Arid

DOI	10.1039/d3em00469d
	Effects of carbonate on ferrihydrite transformation in alkaline media
	Li, Ying; Zhang, Chaoqun; Yang, Meijun; Liu, Jing; He, Hongping; Ma, Yibing; Arai, Yuji
通讯作者	Li, Y
来源期刊	ENVIRONMENTAL SCIENCE-PROCESSES & IMPACTS
ISSN	2050-7887
EISSN	2050-7895
出版年	2024
卷号	26 期号:2 页码:288-297
英文摘要	Alkaline media widely exist in natural and engineered systems such as semiarid/arid areas, radioactive waste sites, and mine tailings. In these settings, the commonly occurring iron (oxyhydr)oxides differed in their ability to influence the fate of nutrients and contaminants. Due to the substantially increased atmospheric carbon dioxide (CO2) concentration, carbonate stands to increase in these media. However, how increasing carbonate affects the transformation of poorly crystalline iron (oxyhydr)oxides (e.g., two-line ferrihydrite) under alkaline conditions still remains unclear. Here, kinetics of ferrihydrite transformation were evaluated at pH similar to 10 as a function of [carbonate] = 0-286 mM using synchrotron-based X-ray and vibrational spectroscopic techniques. The results showed that carbonate slowed down ferrihydrite transformation slightly and suppressed goethite formation, but promoted hematite formation regardless of its concentration. At low carbonate concentration (11.42 mM), the effect of carbonate on product formation was obvious due to the weak inner-sphere complex; however, at high carbonate concentration (80-286 mM), the effect was retarded because of the adsorption equilibrium of carbonate as well as the initial carbonate adsorption followed by desorption. Moreover, carbonate modified the morphology of hematite from rhombic to ellipsoidal to honeycomb and goethite from rod-like to needle-like to spindle-like due to the inner-sphere adsorption-desorption of carbonate and adsorption of hydroxyl ions on reactive sites of iron (oxyhydr)oxides in alkaline media. The results suggest that the concurrently increasing carbonate with enhanced atmospheric CO2 could control the transformation and occurrence of iron (oxyhydr)oxides in natural and engineered environments and have important implications for the biogeochemical cycles of iron and carbon. This study indicates that in alkaline media, carbonate slightly inhibits ferrihydrite transformation and suppresses goethite formation, but promotes hematite formation, which has important implications for elemental biogeochemical cycles.
类型	Article
语种	英语
收录类别	SCI-E
WOS记录号	WOS:001146710700001
WOS关键词	PHASE-TRANSFORMATION ; 2-LINE FERRIHYDRITE ; ADSORBED ARSENATE ; HEMATITE ; ADSORPTION ; GOETHITE ; PH ; CRYSTALLIZATION ; ABSORPTION ; KINETICS
WOS类目	Chemistry, Analytical ; Environmental Sciences
WOS研究方向	Chemistry ; Environmental Sciences & Ecology
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/403669
推荐引用方式 GB/T 7714	Li, Ying,Zhang, Chaoqun,Yang, Meijun,et al. Effects of carbonate on ferrihydrite transformation in alkaline media[J],2024,26(2):288-297.
APA	Li, Ying.,Zhang, Chaoqun.,Yang, Meijun.,Liu, Jing.,He, Hongping.,...&Arai, Yuji.(2024).Effects of carbonate on ferrihydrite transformation in alkaline media.ENVIRONMENTAL SCIENCE-PROCESSES & IMPACTS,26(2),288-297.
MLA	Li, Ying,et al."Effects of carbonate on ferrihydrite transformation in alkaline media".ENVIRONMENTAL SCIENCE-PROCESSES & IMPACTS 26.2(2024):288-297.