|
|
Adsorption of fluoride on clay minerals and their mechanisms using X-ray photoelectron spectroscopy |
Junyi DU, Daishe WU(), Huayun XIAO, Ping LI |
Department of Environmental Science and Engineering, Nanchang University, Nanchang 330031, China |
|
|
Abstract This research investigates the adsorption mechanisms of fluoride (F) on four clay minerals (kaolinite, montmorillonite, chlorite, and illite) under different F- concentrations and reaction times by probing their fluoride superficial layer binding energies and element compositions using X-ray photoelectron spectroscopy (XPS). At high F- concentrations (C0 = 5–1000 mg·L-1), the amount of F- adsorbed (QF), amount of hydroxide released by clay minerals, solution F- concentration, and the pH increase with increasing C0. The increases are remarkable at C0>50 mg·L-1. The QF increases significantly by continuously modifying the pH level. At C0<5–100 mg·L-1, clay minerals adsorb H+ to protonate aluminum-bound surface-active hydroxyl sites in the superficial layers and induce F- binding. As the C0 increases, F-, along with other cations, is adsorbed to form a quasi-cryolite structure. At C0>100 mg·L-1, new minerals precipitate and the product depends on the critical Al3+ concentration. At [Al3+]>10-11.94 mol·L-1, cryolite forms, while at [Al3+]<10-11.94 mol·L-1, AlF3 is formed. At low C0 (0.3–1.5 mg·L-1), proton transfer occurs, and the F- adsorption capabilities of the clay minerals increase with time.
|
Keywords
clay mineral
fluoride (F)
adsorption mechanism
X-ray photoelectron spectroscopy (XPS)
|
Corresponding Author(s):
WU Daishe,Email:wudaishe@hotmail.com, dswu@ncu.edu.cn
|
Issue Date: 05 June 2011
|
|
1 |
Ozsvath D L. Fluoride and environmental health: a review. Reviews in Environmental Science and Biotechnology , 2009, 8(1): 59–79 doi: 10.1007/s11157-008-9136-9
|
2 |
Wang W Y, Li R B, Luo K L. Adsorption and leaching of fluoride in soils and its health impact. Fluoride , 2002, 35: 122–129
|
3 |
Wu D S, Zheng B S, Wang A M, Yu G Q. Fluoride exposure from burning coal-clay in Guizhou Province, China. Fluoride , 2004, 37: 20–27
|
4 |
Chen G J, Yu D F. Fluorine in Environment. Beijing: Scientific Press, 1990 (in Chinese)
|
5 |
Wu W, Xie Z, Xu J, Hong Z, Liu C. Characteristics of forms of fluorine in soils and influential factors. Huan Jing Ke Xue , 2002, 23(2): 104–108 (in Chinese)
|
6 |
Samson H R. Fluoride adsorption by clay minerals and hydrated aluminum. Clay Mineralogy Bulletin , 1952, 1: 266–271 doi: 10.1180/claymin.1952.001.8.06
|
7 |
Huang P M, Jackson M L. Mechanism of reaction of neutral fluoride solution with layer silicates and oxides of soils. Soil Science Society of America Proceeding , 1965, 29: 661–665
|
8 |
Romo L A. Role of lattice hydroxyls of kaolinite in phosphate fixation and their replacement by fluoride. Journal of Colloid Science , 1954, 9: 385–392 doi: 10.1016/0095-8522(54)90026-4
|
9 |
Kau P M H, Smith D W, Binning P. Experimental sorption of fluoride by kaolinite and bentonite. Geoderma , 1998, 84(1–3): 89–108 doi: 10.1016/S0016-7061(97)00122-5
|
10 |
Weerasooriya R, Wickramarathne H U S, Dharmagunawardhane H A. Surface complexation modeling of fluoride adsorption onto kaolinite. Colloids and Surfaces A: Physicochemical and Engineering Aspects , 1998, 144(1–3): 267–273 doi: 10.1016/S0927-7757(98)00646-3
|
11 |
Semmens B, Meggy A B. The reaction of kaolin with fluorides I. Effect of neutral and acid sodium fluoride solutions. Journal of Applied Chemistry , 1966, 16: 122–125 doi: 10.1002/jctb.5010160403
|
12 |
He Q, Chen J F. Preliminary study on release of hydroxo group from surface of soil colloids. Acta Pedology Sinica , 1984, 21(4): 401–409 (in Chinese)
|
13 |
Bower C A, Hatcher J T. Adsorption of fluoride by soils and minerals. Soil Science , 1967, 103(3): 151–154 doi: 10.1097/00010694-196703000-00001
|
14 |
Harrington L F, Cooper E M, Vasudevan D. Fluoride sorption and associated aluminum release in variable charge soils. Journal of Colloid and Interface Science , 2003, 267(2): 302–313 doi: 10.1016/S0021-9797(03)00609-X
|
15 |
Wang H H, Zhu M X, Jiang X, Wang F. Interaction of fluoride with red soil and its environmental implications. Journal of Agro-Environment Science , 2006, 25(4): 974–978 (in Chinese)
|
16 |
Barrow N J, Shaw T C. The slow reactions between soil and anions: 6. Effect of time and temperature of contact on fluoride. Soil Science , 1977, 124(5): 265–278 doi: 10.1097/00010694-197711000-00003
|
17 |
Koppelman M H, Emerson A B, Dillard J G. Adsorbed Cr(III) on chlorite, illite, and kaolinite: an X-ray photoelectron spectroscopic study. Clays and Clay Minerals , 1980, 28(2): 119–124 doi: 10.1346/CCMN.1980.0280207
|
18 |
Koppelman M H, Dillard J G. A study of the adsorption of Ni(II) and Cu(II) by clay minerals. Clays and Clay Minerals , 1977, 25(6): 457–462 doi: 10.1346/CCMN.1977.0250612
|
19 |
Koppelman M H, Dillard J G. Adsorption of Cr(NH3)63+ and Cr(en)33+ on clay minerals and the characterization of chromium by X-ray photoelectron spectroscopy. Clays and Clay Minerals , 1980, 28(3): 211–216 doi: 10.1346/CCMN.1980.0280307
|
20 |
Koppelman M H, Dillard J G. An X-ray photoelectron spectroscopic (XPS) study of cobalt adsorbed on the clay mineral chlorite. Journal of Colloid and Interface Science , 1978, 66(2): 345–351 doi: 10.1016/0021-9797(78)90313-2
|
21 |
Zhu L J, Li J Y, Mu C G. Environmental Geochemistry of fluorine in the rock, soil and water system in the karst areas of central Guizhou. Carsologica Sinica , 1999, 18(2): 109–115
|
22 |
State Bureau of Technical Supervision. GB7484–87, Water quality-Determination of fluoride-Ion selective electrode method. Beijing: Standardization Administration of the People's Republic of China, 1987, <http://www.sac.gov.cn> (in Chinese)
|
23 |
Dickman S R, Bray R H. Replacement of adsorbed phosphate from kaolinite by fluoride. Soil Science , 1941, 52(4): 263–274 doi: 10.1097/00010694-194110000-00002
|
24 |
Bracewell J M, Campell A S, Mitchell B D. An assessment of some thermal and chemical techniques used in the study of poorly-ordered alumino-silicates in soil clays. Clay Minerals , 1970, 8(3): 325–335 doi: 10.1180/claymin.1970.008.3.10
|
25 |
State Bureau of Technical Supervision. GB/T603–2002, Chemical reagents-Preparations of reagent solutions for use in test methods. Beijing: Standardization Administration of the People's Republic of China, 2002<http://www.sac.gov.cn> (in Chinese)
|
26 |
Nordin J P, Sullivan D J, Phillips B L, Casey W H. Mechanisms for fuoride-promoted dissolution of bayerite [β-Al(OH)3(s)] and boehmite [γ-AlOOH]: 19F-NMR spectroscopy and aqueous surface chemistry. Geochimica et Cosmochimica Acta , 1999, 63(21): 3513–3524 doi: 10.1016/S0016-7037(99)00185-4
|
27 |
Pulfer K, Schindler P W, Westall J C, Grauer R. Kinetics and mechanism of dissolution of bayerite (γ-AI(OH)3) in HNO3-HF solutions at 298.2°K. Journal of Colloid and Interface Science , 1984, 101(2): 554–564 doi: 10.1016/0021-9797(84)90067-5
|
28 |
Parfitt R L, Russel J D. Adsorption on hydrous oxides: 4. Mechanisms of adsorption of various ions on geothite. Journal of Soil Science , 1977, 28(2): 297–305 doi: 10.1111/j.1365-2389.1977.tb02238.x
|
29 |
Hiemstra T, Riemsdijk W H V. Fluoride adsorption on goethite in relation to different types of surface sites. Journal of Colloid and Interface Science , 2000, 225(1): 94–104 doi: 10.1006/jcis.1999.6697
|
30 |
Phillips B L, Casey W H, Crawford S N. Solvent exchange in AlFx(H2O)3-x6-x(aq) complexes: Ligand-directed labilization of water as an analogue for ligand-induced dissolution of oxide minerals. Geochimica et Cosmochimica Acta , 1997, 61(15): 3041–3049 doi: 10.1016/S0016-7037(97)00149-X
|
31 |
Elrashidi M A, Lindsay W L. Chemical equilibria of fluorine in soils: a theoretical development. Soil Science , 1986, 141(4): 274–280 doi: 10.1097/00010694-198604000-00004
|
|
Viewed |
|
|
|
Full text
|
|
|
|
|
Abstract
|
|
|
|
|
Cited |
|
|
|
|
|
Shared |
|
|
|
|
|
Discussed |
|
|
|
|