Viscous flow and crystallization behaviors of p-bearing steelmaking slags with varying fluorine content

Zhanjun Wang; Yongqi Sun; Sridhar Seetharaman; Mei Zhang; Min Guo; Zhongmin Li; Zhancheng Guo; Zuotai Zhang

doi:10.2355/isijinternational.ISIJINT-2015-538

Viscous flow and crystallization behaviors of p-bearing steelmaking slags with varying fluorine content

Zhanjun Wang, Yongqi Sun, Sridhar Seetharaman, Mei Zhang, Min Guo, Zhongmin Li, Zhancheng Guo, Zuotai Zhang

Research output: Contribution to journal › Article › peer-review

15 Scopus citations

Abstract

The role of fluorine in the CaO-SiO₂-MgO-Al₂O₃-FetO steelmaking slags was investigated through analyzing the viscous flow and crystallization behaviors of the slags. It was found that the viscosity decreased with increasing CaF₂ content, which resulted from the decrease of the degree of polymerization (DOP) of the structures, as proved by O^1s X-ray photoelectron spectroscopy (XPS) and magic angular spinning nuclear magnetic resonance (MAS-NMR) analysis. The continuous cooling transformation (CCT) diagrams of the primary crystals were also constructed. The results showed that CaF₂ addition promoted the transformation of the primary crystal from spinel (MgFe₂O₄) to flourapatite (Ca₅(PO₄)₃F, which was beneficial to the further enrichment of phosphorus. According to ¹⁹F MAS-NMR results, F^- ions mainly coordinate with Ca²⁺ ions to form Ca-F bond. Furthermore, considering the greater stability of P-O-Ca than that of Si-O- Ca bonds, most of the F- ions behave as F-Ca-O-P band, which thus enhanced the formation of Ca₅(PO₄)₃F. Additionally, the non-isothermal crystallization kinetics was further analyzed and the activation energy for the primary crystal growth was derived.

Original language	English (US)
Pages (from-to)	546-553
Number of pages	8
Journal	ISIJ International
Volume	56
Issue number	4
DOIs	https://doi.org/10.2355/isijinternational.ISIJINT-2015-538
State	Published - 2016
Externally published	Yes

Keywords

Fluorine
Kinetics
Steelmaking slags
Structure
Viscous flow

ASJC Scopus subject areas

Mechanics of Materials
Mechanical Engineering
Metals and Alloys
Materials Chemistry

Access to Document

10.2355/isijinternational.ISIJINT-2015-538

Cite this

@article{24cedeeadf1d4ffbb018d4c3e4abbbfb,

title = "Viscous flow and crystallization behaviors of p-bearing steelmaking slags with varying fluorine content",

abstract = "The role of fluorine in the CaO-SiO2-MgO-Al2O3-FetO steelmaking slags was investigated through analyzing the viscous flow and crystallization behaviors of the slags. It was found that the viscosity decreased with increasing CaF2 content, which resulted from the decrease of the degree of polymerization (DOP) of the structures, as proved by O1s X-ray photoelectron spectroscopy (XPS) and magic angular spinning nuclear magnetic resonance (MAS-NMR) analysis. The continuous cooling transformation (CCT) diagrams of the primary crystals were also constructed. The results showed that CaF2 addition promoted the transformation of the primary crystal from spinel (MgFe2O4) to flourapatite (Ca5(PO4)3F, which was beneficial to the further enrichment of phosphorus. According to 19F MAS-NMR results, F- ions mainly coordinate with Ca2+ ions to form Ca-F bond. Furthermore, considering the greater stability of P-O-Ca than that of Si-O- Ca bonds, most of the F- ions behave as F-Ca-O-P band, which thus enhanced the formation of Ca5(PO4)3F. Additionally, the non-isothermal crystallization kinetics was further analyzed and the activation energy for the primary crystal growth was derived.",

keywords = "Fluorine, Kinetics, Steelmaking slags, Structure, Viscous flow",

author = "Zhanjun Wang and Yongqi Sun and Sridhar Seetharaman and Mei Zhang and Min Guo and Zhongmin Li and Zhancheng Guo and Zuotai Zhang",

note = "Funding Information: Supports by the National Natural Science Foundation of China (51522401, 51472007, 51372019), and National High Technology Research and Development Program of China (863 Program, 2012AA06A114) are acknowledged. Publisher Copyright: {\textcopyright} 2016 ISIJ.",

year = "2016",

doi = "10.2355/isijinternational.ISIJINT-2015-538",

language = "English (US)",

volume = "56",

pages = "546--553",

journal = "ISIJ International",

issn = "0915-1559",

publisher = "Iron and Steel Institute of Japan",

number = "4",

}

TY - JOUR

T1 - Viscous flow and crystallization behaviors of p-bearing steelmaking slags with varying fluorine content

AU - Wang, Zhanjun

AU - Sun, Yongqi

AU - Seetharaman, Sridhar

AU - Zhang, Mei

AU - Guo, Min

AU - Li, Zhongmin

AU - Guo, Zhancheng

AU - Zhang, Zuotai

N1 - Funding Information: Supports by the National Natural Science Foundation of China (51522401, 51472007, 51372019), and National High Technology Research and Development Program of China (863 Program, 2012AA06A114) are acknowledged. Publisher Copyright: © 2016 ISIJ.

PY - 2016

Y1 - 2016

N2 - The role of fluorine in the CaO-SiO2-MgO-Al2O3-FetO steelmaking slags was investigated through analyzing the viscous flow and crystallization behaviors of the slags. It was found that the viscosity decreased with increasing CaF2 content, which resulted from the decrease of the degree of polymerization (DOP) of the structures, as proved by O1s X-ray photoelectron spectroscopy (XPS) and magic angular spinning nuclear magnetic resonance (MAS-NMR) analysis. The continuous cooling transformation (CCT) diagrams of the primary crystals were also constructed. The results showed that CaF2 addition promoted the transformation of the primary crystal from spinel (MgFe2O4) to flourapatite (Ca5(PO4)3F, which was beneficial to the further enrichment of phosphorus. According to 19F MAS-NMR results, F- ions mainly coordinate with Ca2+ ions to form Ca-F bond. Furthermore, considering the greater stability of P-O-Ca than that of Si-O- Ca bonds, most of the F- ions behave as F-Ca-O-P band, which thus enhanced the formation of Ca5(PO4)3F. Additionally, the non-isothermal crystallization kinetics was further analyzed and the activation energy for the primary crystal growth was derived.

AB - The role of fluorine in the CaO-SiO2-MgO-Al2O3-FetO steelmaking slags was investigated through analyzing the viscous flow and crystallization behaviors of the slags. It was found that the viscosity decreased with increasing CaF2 content, which resulted from the decrease of the degree of polymerization (DOP) of the structures, as proved by O1s X-ray photoelectron spectroscopy (XPS) and magic angular spinning nuclear magnetic resonance (MAS-NMR) analysis. The continuous cooling transformation (CCT) diagrams of the primary crystals were also constructed. The results showed that CaF2 addition promoted the transformation of the primary crystal from spinel (MgFe2O4) to flourapatite (Ca5(PO4)3F, which was beneficial to the further enrichment of phosphorus. According to 19F MAS-NMR results, F- ions mainly coordinate with Ca2+ ions to form Ca-F bond. Furthermore, considering the greater stability of P-O-Ca than that of Si-O- Ca bonds, most of the F- ions behave as F-Ca-O-P band, which thus enhanced the formation of Ca5(PO4)3F. Additionally, the non-isothermal crystallization kinetics was further analyzed and the activation energy for the primary crystal growth was derived.

KW - Fluorine

KW - Kinetics

KW - Steelmaking slags

KW - Structure

KW - Viscous flow

UR - http://www.scopus.com/inward/record.url?scp=84968680165&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84968680165&partnerID=8YFLogxK

U2 - 10.2355/isijinternational.ISIJINT-2015-538

DO - 10.2355/isijinternational.ISIJINT-2015-538

M3 - Article

AN - SCOPUS:84968680165

SN - 0915-1559

VL - 56

SP - 546

EP - 553

JO - ISIJ International

JF - ISIJ International

IS - 4

ER -

Viscous flow and crystallization behaviors of p-bearing steelmaking slags with varying fluorine content

Abstract

Keywords

ASJC Scopus subject areas

Access to Document

Other files and links

Fingerprint

Cite this