Influence of calcium hydroxide on the fate of perfluorooctanesulfonate under thermal conditions

Fei Wang; Xingwen Lu; Kaimin Shih; Chengshuai Liu

doi:10.1016/j.jhazmat.2011.06.009

Influence of calcium hydroxide on the fate of perfluorooctanesulfonate under thermal conditions

Fei Wang, Xingwen Lu, Kaimin Shih, Chengshuai Liu

The Hong Kong Polytechnic University

Research output: Journal article publication › Journal article › Academic research › peer-review

38 Citations (Scopus)

Abstract

To explore the potential fate and transport of perfluorochemicals in the thermal treatment of sludge, perfluorooctanesulfonate (PFOS), a perfluorochemical species commonly dominant in wastewater sludge, was mixed with hydrated lime (Ca(OH)₂) to quantitatively observe their interaction under different temperatures. The phase compositions of the mixtures after the reactions were qualitatively identified and quantitatively determined using X-ray diffraction technique. The results of the thermogravimetry and differential scanning calorimetry analyses indicate that PFOS gasified directly during the thermal treatment process when the temperature was increased to around 425°C. However, the formation of CaF₂ at 350°C suggests that the presence of Ca(OH)₂ in the mixture can lead to the decomposition of PFOS at 350°C, which is lower than the decomposition temperature of PFOS alone (425°C). The increase of temperature promoted a solid state reaction between PFOS and Ca(OH)₂, and also enhanced the interaction between the gaseous products of PFOS and CaO (or Ca(OH)₂). The preferred Ca/F molar ratio to achieve fluorine stabilization by Ca(OH)₂ was above 1:1 in the experiment involving 400°C and 600°C treatment. It also showed that equilibrium efficiency is achieved within 5min at 400°C and within 1min above 600°C.

Original language	English
Pages (from-to)	1067-1071
Number of pages	5
Journal	Journal of Hazardous Materials
Volume	192
Issue number	3
DOIs	https://doi.org/10.1016/j.jhazmat.2011.06.009
Publication status	Published - 15 Sept 2011

Keywords

PFOS
Transformation ratio
XRD quantification

ASJC Scopus subject areas

Environmental Engineering
Environmental Chemistry
Waste Management and Disposal
Pollution
Health, Toxicology and Mutagenesis

More information

10.1016/j.jhazmat.2011.06.009

Cite this

@article{57f93166104747ada355c686875bcb73,

title = "Influence of calcium hydroxide on the fate of perfluorooctanesulfonate under thermal conditions",

abstract = "To explore the potential fate and transport of perfluorochemicals in the thermal treatment of sludge, perfluorooctanesulfonate (PFOS), a perfluorochemical species commonly dominant in wastewater sludge, was mixed with hydrated lime (Ca(OH)2) to quantitatively observe their interaction under different temperatures. The phase compositions of the mixtures after the reactions were qualitatively identified and quantitatively determined using X-ray diffraction technique. The results of the thermogravimetry and differential scanning calorimetry analyses indicate that PFOS gasified directly during the thermal treatment process when the temperature was increased to around 425°C. However, the formation of CaF2 at 350°C suggests that the presence of Ca(OH)2 in the mixture can lead to the decomposition of PFOS at 350°C, which is lower than the decomposition temperature of PFOS alone (425°C). The increase of temperature promoted a solid state reaction between PFOS and Ca(OH)2, and also enhanced the interaction between the gaseous products of PFOS and CaO (or Ca(OH)2). The preferred Ca/F molar ratio to achieve fluorine stabilization by Ca(OH)2 was above 1:1 in the experiment involving 400°C and 600°C treatment. It also showed that equilibrium efficiency is achieved within 5min at 400°C and within 1min above 600°C.",

keywords = "PFOS, Transformation ratio, XRD quantification",

author = "Fei Wang and Xingwen Lu and Kaimin Shih and Chengshuai Liu",

note = "Funding Information: We gratefully acknowledge the funding for this research provided by the General Research Fund Scheme of the Research Grants Council of Hong Kong ( HKU 716809E ). ",

year = "2011",

month = sep,

day = "15",

doi = "10.1016/j.jhazmat.2011.06.009",

language = "English",

volume = "192",

pages = "1067--1071",

journal = "Journal of Hazardous Materials",

issn = "0304-3894",

publisher = "Elsevier B.V.",

number = "3",

}

TY - JOUR

T1 - Influence of calcium hydroxide on the fate of perfluorooctanesulfonate under thermal conditions

AU - Wang, Fei

AU - Lu, Xingwen

AU - Shih, Kaimin

AU - Liu, Chengshuai

N1 - Funding Information: We gratefully acknowledge the funding for this research provided by the General Research Fund Scheme of the Research Grants Council of Hong Kong ( HKU 716809E ).

PY - 2011/9/15

Y1 - 2011/9/15

N2 - To explore the potential fate and transport of perfluorochemicals in the thermal treatment of sludge, perfluorooctanesulfonate (PFOS), a perfluorochemical species commonly dominant in wastewater sludge, was mixed with hydrated lime (Ca(OH)2) to quantitatively observe their interaction under different temperatures. The phase compositions of the mixtures after the reactions were qualitatively identified and quantitatively determined using X-ray diffraction technique. The results of the thermogravimetry and differential scanning calorimetry analyses indicate that PFOS gasified directly during the thermal treatment process when the temperature was increased to around 425°C. However, the formation of CaF2 at 350°C suggests that the presence of Ca(OH)2 in the mixture can lead to the decomposition of PFOS at 350°C, which is lower than the decomposition temperature of PFOS alone (425°C). The increase of temperature promoted a solid state reaction between PFOS and Ca(OH)2, and also enhanced the interaction between the gaseous products of PFOS and CaO (or Ca(OH)2). The preferred Ca/F molar ratio to achieve fluorine stabilization by Ca(OH)2 was above 1:1 in the experiment involving 400°C and 600°C treatment. It also showed that equilibrium efficiency is achieved within 5min at 400°C and within 1min above 600°C.

AB - To explore the potential fate and transport of perfluorochemicals in the thermal treatment of sludge, perfluorooctanesulfonate (PFOS), a perfluorochemical species commonly dominant in wastewater sludge, was mixed with hydrated lime (Ca(OH)2) to quantitatively observe their interaction under different temperatures. The phase compositions of the mixtures after the reactions were qualitatively identified and quantitatively determined using X-ray diffraction technique. The results of the thermogravimetry and differential scanning calorimetry analyses indicate that PFOS gasified directly during the thermal treatment process when the temperature was increased to around 425°C. However, the formation of CaF2 at 350°C suggests that the presence of Ca(OH)2 in the mixture can lead to the decomposition of PFOS at 350°C, which is lower than the decomposition temperature of PFOS alone (425°C). The increase of temperature promoted a solid state reaction between PFOS and Ca(OH)2, and also enhanced the interaction between the gaseous products of PFOS and CaO (or Ca(OH)2). The preferred Ca/F molar ratio to achieve fluorine stabilization by Ca(OH)2 was above 1:1 in the experiment involving 400°C and 600°C treatment. It also showed that equilibrium efficiency is achieved within 5min at 400°C and within 1min above 600°C.

KW - PFOS

KW - Transformation ratio

KW - XRD quantification

UR - http://www.scopus.com/inward/record.url?scp=80052038196&partnerID=8YFLogxK

U2 - 10.1016/j.jhazmat.2011.06.009

DO - 10.1016/j.jhazmat.2011.06.009

M3 - Journal article

C2 - 21719193

AN - SCOPUS:80052038196

SN - 0304-3894

VL - 192

SP - 1067

EP - 1071

JO - Journal of Hazardous Materials

JF - Journal of Hazardous Materials

IS - 3

ER -

Influence of calcium hydroxide on the fate of perfluorooctanesulfonate under thermal conditions

Abstract

Keywords

ASJC Scopus subject areas

More information

Other files and links

Fingerprint

Cite this