粘土矿物吸附氟的作用机制及硫酸铝浸渍活性氧化铝球吸附研究
|
摘要
为了研究粘土矿物吸附氟后的表层形态变化和反应机制,四种粘土矿物(高岭石、蒙脱石、绿泥石、伊利石)浸泡在高氟浓度溶液(5-1000 mg/L)和低氟浓度溶液(0.3-1.5 mg/L)进行吸附实验,并利用X射线光电子能谱进行表面形态分析。粘土矿物在高氟浓度溶液吸附时,溶液平衡氟浓度、吸附量、溶液pH和释放羟基量随氟浓度增加而增加；而且吸附量在50/100 mg/L以上时显著增加。用酸碱调节维持氟溶液pH时,粘土矿物氟吸附量增加。各浓度浸泡后吸附数据和氟电子能峰位表明：粘土矿物在氟浓度溶液小于5～100 mg/L时预先吸附氢离子使表面活性位质子化,然后与氟发生交换；随氟浓度升高,氟直接交换铝活性位羟基,并且与其它阳离子结合；而在氟溶液浓度大于100 mg/L时生成冰晶石(及氟化铝)沉淀。粘土矿物在高氟浓度溶液吸附时生成的新矿物与溶液铝离子浓度有关,铝离子浓度大于10-11.94mol/L生成冰晶石沉淀,铝离子浓度小于10-11.94mol/L生成氟化铝沉淀。粘土矿物在低氟浓度溶液吸附时会发生质子迁移现象,这使得溶液氟浓度随时间推移持续降低。
研究了硫酸铝浸渍活性氧化铝球(AIAA)处理高氟水的能力。静态实验通过改变吸附剂量(2-40 g/L)、氟浓度(2-100 mg/L)、pH(4-10)、温度(11-33℃)、时间,研究这些因素对吸附过程的影响。动态柱实验研究氟浓度(10-50 mg/L)、流速(2-10mL/min)、填料高(10-20 cm)三个操作参数对柱除氟性能的影响。当温度11-33℃、pH4-10、吸附剂量20g/L时,AIAA 3h内处理10 mg/L氟溶液效率可达90%以上,少量阴离子的共存对氟离子的吸附没有影响。吸附平衡拟合模型表明低浓度氟溶液的吸附中,Langmuir模型线性拟合或非线性拟合是最优拟合方式；而高浓度氟溶液的吸附中,Freundlich模型非线性拟合是最优拟合方式。热力学研究表明AIAA吸附主要为化学吸附；动力学研究表明吸附速度受表面扩散控制,吸附反应更符合二级动力学。动态柱实验中降低流速、增加填料层高度可以提高除氟效果。0.1M NaOH再生效果良好,三次更换再生液基本可以完全解吸。
Kaolinite (K), Montmorillonite (M), Chlorite (Ch), Illite (I) are four representative clay minerals in nature which are selected as research objects. This research investigates fluoride (F-) adsorption mechanism onto four kinds of clay minerals under different pH, F- concentration and reaction time, and studies superficial layers morphology of F as well as elements composition by X-ray photoelectron spectroscopy (XPS) analysis. In high F- concentration(Co) solution (5-1000 mg/L), F-adsorption amount(QF), hydroxyl release amount(HRA) of clay minerals, equilibrium F- concentration(CF) and equilibrium pH increase with increasing Co, especially remarkably when above 50 mg/L. And by modifying and maintaining solution pH at 6, F- adsorption amount of clay minerals is higher than that without pH regulation. Various adsorption data and F- binding energy of superficial layers (FSBE) detected by XPS indicate that at Co less than 5-100 mg/L clay minerals firstly adsorb H+ to protonate aluminum active hydroxyl sites (AAHS) in superficial layers, and react with F-; and as Co gradually increases clay minerals can adsorb F- directly together with the adsorption of some cations; and at Co greater than 100 mg/L F- precipitates in the forms of cryolite or AIF3. The type of new minerals formed in superficial layers in high Co solution depends on Al3+ concentration (CAl)-cryolite at CAl greater than 10-11.94mol/L, AIF3 at CAl less than 10-11.94mol/L. In low CO (0.3-1.5 mg/L) solution proton transfer occurs to make CF decrease continuously with passing of time.
The second chapter research the defluoridation capacity of aluminum sulfate impregnated alumina granule (AIAA) in treating high fluoride water. Batch experiments study the influence of operational factors on fluoride adsorption by varying adsorption amount (2-40 g/L), fluoride concentration (2-100 mg/L), pH (4-10), temperature (11-33℃), time. Column experiments study the influence of fluoride concentration (10-50 mg/L), flow rate (2-10 mL/min), filler height (10-20 cm) on defluoridation capacity of AIAA column. At 11-33℃, pH 4-10 and adsorbents amount 20 g/L, the efficiency of AIAA treating 10 mg/L fluoride solution in 3 h is more than 90%, and the existence of a little amount of anions do not influence fluoride adsorption. The study of adsorption equilibrium fitting models illustrate that Langamuir model linear fitting is the optimistic fitting method when AIAA in low fluoride concentration solution; while Freundlich model non-linear fitting is the optimistic fitting method when AIAA in high fluoride concentration solution. Thermodynamic studies show that chemical adsorption plays the dominant role of fluoride adsorption by AIAA; kinetic studies show that adsorption rate is controlled by surface diffusion process and adsorption reaction tallies with pseudo-second order kinetics. In column experiments, lowering flow rate or increasing filler height can improve defluoridation efficiency. In regeneration process,0.01 M NaOH has the best regenerated effect which can regenerate saturated AIAA completely by three times renewing.
研究了硫酸铝浸渍活性氧化铝球(AIAA)处理高氟水的能力。静态实验通过改变吸附剂量(2-40 g/L)、氟浓度(2-100 mg/L)、pH(4-10)、温度(11-33℃)、时间,研究这些因素对吸附过程的影响。动态柱实验研究氟浓度(10-50 mg/L)、流速(2-10mL/min)、填料高(10-20 cm)三个操作参数对柱除氟性能的影响。当温度11-33℃、pH4-10、吸附剂量20g/L时,AIAA 3h内处理10 mg/L氟溶液效率可达90%以上,少量阴离子的共存对氟离子的吸附没有影响。吸附平衡拟合模型表明低浓度氟溶液的吸附中,Langmuir模型线性拟合或非线性拟合是最优拟合方式；而高浓度氟溶液的吸附中,Freundlich模型非线性拟合是最优拟合方式。热力学研究表明AIAA吸附主要为化学吸附；动力学研究表明吸附速度受表面扩散控制,吸附反应更符合二级动力学。动态柱实验中降低流速、增加填料层高度可以提高除氟效果。0.1M NaOH再生效果良好,三次更换再生液基本可以完全解吸。
Kaolinite (K), Montmorillonite (M), Chlorite (Ch), Illite (I) are four representative clay minerals in nature which are selected as research objects. This research investigates fluoride (F-) adsorption mechanism onto four kinds of clay minerals under different pH, F- concentration and reaction time, and studies superficial layers morphology of F as well as elements composition by X-ray photoelectron spectroscopy (XPS) analysis. In high F- concentration(Co) solution (5-1000 mg/L), F-adsorption amount(QF), hydroxyl release amount(HRA) of clay minerals, equilibrium F- concentration(CF) and equilibrium pH increase with increasing Co, especially remarkably when above 50 mg/L. And by modifying and maintaining solution pH at 6, F- adsorption amount of clay minerals is higher than that without pH regulation. Various adsorption data and F- binding energy of superficial layers (FSBE) detected by XPS indicate that at Co less than 5-100 mg/L clay minerals firstly adsorb H+ to protonate aluminum active hydroxyl sites (AAHS) in superficial layers, and react with F-; and as Co gradually increases clay minerals can adsorb F- directly together with the adsorption of some cations; and at Co greater than 100 mg/L F- precipitates in the forms of cryolite or AIF3. The type of new minerals formed in superficial layers in high Co solution depends on Al3+ concentration (CAl)-cryolite at CAl greater than 10-11.94mol/L, AIF3 at CAl less than 10-11.94mol/L. In low CO (0.3-1.5 mg/L) solution proton transfer occurs to make CF decrease continuously with passing of time.
The second chapter research the defluoridation capacity of aluminum sulfate impregnated alumina granule (AIAA) in treating high fluoride water. Batch experiments study the influence of operational factors on fluoride adsorption by varying adsorption amount (2-40 g/L), fluoride concentration (2-100 mg/L), pH (4-10), temperature (11-33℃), time. Column experiments study the influence of fluoride concentration (10-50 mg/L), flow rate (2-10 mL/min), filler height (10-20 cm) on defluoridation capacity of AIAA column. At 11-33℃, pH 4-10 and adsorbents amount 20 g/L, the efficiency of AIAA treating 10 mg/L fluoride solution in 3 h is more than 90%, and the existence of a little amount of anions do not influence fluoride adsorption. The study of adsorption equilibrium fitting models illustrate that Langamuir model linear fitting is the optimistic fitting method when AIAA in low fluoride concentration solution; while Freundlich model non-linear fitting is the optimistic fitting method when AIAA in high fluoride concentration solution. Thermodynamic studies show that chemical adsorption plays the dominant role of fluoride adsorption by AIAA; kinetic studies show that adsorption rate is controlled by surface diffusion process and adsorption reaction tallies with pseudo-second order kinetics. In column experiments, lowering flow rate or increasing filler height can improve defluoridation efficiency. In regeneration process,0.01 M NaOH has the best regenerated effect which can regenerate saturated AIAA completely by three times renewing.
引文
[1]Ozsvath D L. Fluoride and environmental health:a review[J]. Rev. Environ. Sci. Biotechnol., 2009,8(1):59～79.
[2]Wang W Y, Li R B, Luo K L. Adsorption and leaching of fluoride in soils and its health impact[J]. Fluoride,2002,35(2):122～129.
[3]Wu D S, Zheng B S, Wang A M, et al. Fluoride exposure from burning coal-clay in Guizhou Province, China[J]. Fluoride,2004,37(1):20～27.
[4]陈国阶,余大富编.环境中的氟[M].北京：科学出版社,1990.
[5]Wu W H, Xie Z M, Xu J M, et al. Characteristics of Forms of Fluorine in Soils and Influential Factors[J]. Environmental Science,2002,23(2):104～108.
[6]Samson H R. Fluoride adsorption by clay minerals and hydrated aluminum[J]. Clay minerals Bulletin,1952:266～271.
[7]Huang P M, Jackson M L. Mechanism of reaction of neutral fluoride solution with layer silicates and oxides of soils[J]. Soil Sci. Soc. Amer. Proc.,29(1965):661～665.
[8]Romo L A. Role of lattice hydroxyls in phosphate fixation and their replacement by fluoride[J]. J. Colloid Chem.,1954,9(5):385～392.
[9]Kau P M H, Smith D W, Binning P. Expterimental sorption of fluoride by kaolinite and bentonite[J]. Geoderma,1998,84(1-3):89～108.
[10]Weerasooriya R, Wickramarathne H U S, Dharmagunawardhane H A. Surface complexation modeling of fluoride adsorption onto kaolinite[J]. Colloids and Surfaces A: Physicochemical and Engineering Aspects,1998,144(1-3):267～273.
[11]Semmens B, Meggy A B. The reation of kaolin with fluorides I. Effect of neutral and acid sodium fluoride solutions[J]. J. appl. Chem.,1966,16(4):122～125.
[12]He Q, Chen J F. Preliminary study on release of hydroxo group from surface of soil colloids[J]. Acta Pedology Sinica,1984,21(4):401～409.
[13]Bower C A, Hatcher J T. Adsorption of fluoride by soils and minerals[J]. Soil Science,1967, 103(3):151～154.
[14]Harrington L F, Cooper E M, Vasudevan D. Fluoride sorption and associated aluminum release in variable charge soils[J]. Journal of Colloid and Interface Science,2003,267(2): 302～313.
[15]Wang H H, Zhu M X, Jiang X, et al. Interaction of fluoride with red soil and its environmental implications[J]. Journal of Agro-Environment Science,2006,25(4): 974～978.
[16]Barrow N J, Shaw T C. The slow reactions between soil and anions:6. Effect of time and temperature of contact on fluoride[J]. Soil Science,1977,124(5):265～278.
[17]Koppelman E H, Emerson A B, Dillard J G. Adsorbed Cr(Ⅲ) on chlorite, illite, and kaolinite:an X-ray photoelectron spectroscopic study[J]. Clays and Clay Minerals,1980, 28(2):119～124.
[18]Koppelman M H, Dillard J G. A study of the adsorption of Ni(Ⅱ) and Cu(Ⅱ) by clay minerals[J]. Clay and Clay Minerals,25(1977):457～462.
[19]Koppelman M H, Dillard J G. Adsorpation of Cr(NH3)63+ and Cr(en)33+ on clay minerals and the characterization of chromium by x-ray photoelectron spectroscopy[J]. Clays and clay minerals,1980,28(3):211～216.
[20]Koppelman M H, Dillard J G. An X-ray photoelectron spectroscopic(XPS) study of cobalt adsorbed on the clay mineral chlorite[J]. Journal of Colloid and Interface Science,1978, 66(2):345～351.
[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[J] Carsologica Sinica.1999,18(2): 109～115.
[22]Islam M, Patel R K. Evaluation of removal efficiency of fluoride from aqueous solution using quick lime[J]. Journal of Hazardous Materials,2007,143(1-2):303～310.
[23]Nigussie W, Zewge F, Chandravanshi B S. Removal of excess fluoride from water using waste residue from alum manufacturing process[J]. Journal of Hazardous Materials,2007, 147(3):954～963.
[24]Gopal V, Elango K P. Equilibrium, kinetic and thermodynamic studies of adsorption of fluoride onto plaster of Paris[J]. Journal of Hazardous Materials,2007,141(1):98～105.
[25]Mameri N, Lounici H, Belhocine D, et al. Defluoridation of Sahara water by small plantelectrocoagulation using bipolar aluminium electrodes [J]. Separation and Purification Technology,2001,24(1-2):113～119.
[26]Hichour M, Persin F, Sandeaux J, et al. Fluoride removal from waters by Donnan dialysis[J]. Separation and Purification Technology,2000,18(1):1～11.
[27]Edmunds M, Smedley P. Fluoride in Natural Waters-occurrence, controls and health aspects, Essentials of Medical Geology:Impacts of the Natural Environment on Public Health[M]. Amsterdam:Elsevier Acadamy Press,2005,301～329.
[28]Daifullah A A M, Yakout S M, Elreefy S A. Adsorption of fluoride in aqueous solutions using KMnO4-modified activated carbon derived from steam pyrolysis of rice straw[J]. Journal of Hazardous Materials,2007,147(1-2):633～643.
[29]Maliyekkal S M, Sharma A K, Philip L. Manganese-oxide-coated alumina:A promising sorbent for defluoridation of water[J]. Water Research,2006,40(19):3497～3506.
[30]Meenakshi S, Viswanathan N. Identification of selective ion-exchange resin for fluoride sorption[J]. Journal of Colloid and Interface Science,2007,308(2):438～450.
[31]Hamdi N, Srasra E. Removal of fluoride from acidic wastewater by clay mineral:Effect of solid-liquid ratios[J]. Desalination,2007,206(1-3):238～244.
[32]Das N, Pattanaik P, Das R. Defluoridation of drinking water using activated titanium rich bauxite[J]. Journal of Colloid and Interface Science,2005,292(1):1～10.
[33]Zevenbergen C, van Reeuwijk L P, Frapporti G, et al. A simple method for defluoridation of drinking water at village level by adsorption on Ando soil in Kenya[J]. The Science of the Total Environment,1996,188(2-3):225～232.
[34]Sundaram C S, Viswanathan N, Meenakshi S. Defluoridation chemistry of synthetic hydroxyapatite at nanoscale:Equilibrium and kinetic studies[J]. Journal of Hazardous Materials,2008,155(1-2):206～215.
[35]Lv L, He J, Wei M, et al. Treatment of high fluoride concentration water by MgAl-CO3 layered double hydroxides:Kinetic andequilibrium studies[J]. Water Research,2007,41(7): 1534～1542.
[36]Li Y H, Wang S G, Zhang X F, et al. Adsorption of fluoride from water by aligned carbon nanotubes[J]. Materials Research Bulletin,38(2003):469～476.
[37]Maliyekkal S M, Shukla S, Philip L, et al. Enhanced fluoride removal from drinking water by magnesia-amended activated alumina granules[J]. Chemical Engineering Journal,2008, 140(1-3):183～192.
[38]Tripathy S S, Raichur A M. Abatement of fluoride from water using manganese dioxide-coated activated alumina[J]. Journal of Hazardous Materials,2008,153(3): 1043～1051.
[39]Ghorai S, Pant K K. Equilibrium, kinetics and breakthrough studies for adsorption of fluoride on activated alumina[J]. Separation and Purification Technology,2005,42(3): 265～271.
[40]Tripathy S S, Bersillon J L, Gopal K. Removal of fluoride from drinking water by adsorption onto alum-impregnated activated alumina[J]. Separation and Purification Technology,2006,50(3):310～317.
[41]Ku Y, Chiou H M. The adsorption of fluoride ion from aqueous solution by activated alumina[J]. Water, Air, and Soil Pollution,2002,133(1-4):349～361.
[42]谭冈训,李满,武道吉,等.武城县除氟水厂的设计与运行[J].给水排水,2008,34(3)：25～27.
[43]Water quality-Determination of fluoride-Ion selective elecrode method[S]. GB7484-87,北京：中国标准出版社,1987.
[44]Dickman S R, Bray R H. Replacement of adsorbed phosphate from kaolinite by fluoride[J]. Soil Science,1941,52(4):263～273.
[45]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[J]. Clay Minerals,8(1970):325～335.
[46]Chemical reagents-Preparations of reagent solutions for use in test methods[S]. GB/T603-2002,北京：中国标准出版社,2002.
[47]Orleans R B C, Durand Y, Narjoux B, et al. LaSurface Database in Thermofisher Scientific [DB/OL]. http://www.lasurface.com/accueil/index.php.
[48]Wagner C D, Naumkin A V, Kraut-Vass A, et al. NIST X-ray Photoelectron Spectroscopy Database[DB/OL]. http://srdata.nist.gov/xps/Default.aspx,2003.
[49]Nordin J P, Sullivan D J, Phillips B L, et al. Mechanisms for fuoride-promoted dissolution of bayerite [(3-Al(OH)3(s)] and boehmite[γ-AlOOH]:19F-NMR spectroscopy and aqueous surface chemistry[J]. Geochimica et Cosmochimica Acta,1999,63(21):3513～3524.
[50]Pulfer K, Schindler P W, Westall J C, et al. Kinetics and Mechanism of Dissolution of Bayerite (y-AI(OH)3) in HNO3-HF Solutions at 298.2°K[J]. Journal of Colloid and Interface Science,1984,101(2):554～564.
[51]Parfitt R L, Russel J D. Adsorption on hydrous oxides:4. Mechanisms of adsorption of various ions on geothite[J]. Journal of Soil Science,1977,28(2):297～305.
[52]Hiemstra T, van Riemsdijk W H. Fluoride adsorption on goethite in relation to different types of surface sites[J]. Journal of Colloid and Interface Science,2000,225(1):94～104.
[53]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[J]. Geochimica et Cosmochimica Acta,1997,61(15): 3041～3049.
[54]Elrashidi M A, Lindsay W L. Chemical equilibria of fluorine in soils:a theoretical development[J]. Soil Science,1986,141(4):274～280.
[55]Wang Y X, Reardon E J. Activation and regeneration of a soil sorbent for defluoridation of drinking water[J]. Applied Geochemistry,2001,16(5):531～539.
[56]Su T Z, Guan X H, Gu G W, et al. Adsorption characteristics of As(V), Se(IV), and V(V) onto activated alumina:Effects of pH, surface loading, and ionic strength[J]. Journal of Colloid and Interface Science,2008,326(2):347～353.
[57]Porter J F, McKay G, Choy K H. The prediction of sorption from a binary mixture of acidic dyes using single- and mixed-isotherm variants of the ideal adsorbed solute theory[J]. Chemical Engineering Science,1999,54(24):5863～5885.
[58]Ayoob S, Gupta A K. Insights into isotherm making in the sorptive removal of fluoride from drinking water[J]. Journal of Hazardous Materials,2008,152(3):976～985.
[59]Tang Y L, Guan X H, Su T Z, et al. Fluoride adsorption onto activated alumina:Modeling the effects of pH and some competing ions[J]. Colloids and Surfaces A:Physicochem. Eng. Aspects,2009,337(1-3):33～38.
[60]Sujana M G, Thakur R S, Rao S B. Removal of Fluoride from Aqueous Solution by Using Alum Sludge[J]. Journal of colloid and interface science,1998,206(1):94～101.
[61]Ramanaiah S V, Mohan S V, Sarma P N. Adsorption removal of fluoride from aqueous phase using waste fungus (Pleurotus ostreatus 1804) biosorbent: Kinetics evaluation[J]. Ecological Engineering,2007,31(1):47～56.
[62]Tor A. Removal of fluoride from an aqueous solution byusing montmorillonite[J]. Desalination,2006,201(1-3):267～276.
[63]Mandal S, Mayadevi S. Adsorption offluoride ions by Zn-Al layered double hydroxides[J]. Applied Clay Science,2008,40(1-4):54～62.
[64]Site A D. Factors affecting sorption of organic compounds in natural sorbent/water systems and sorption coefficients for selected pollutants:A review[J]. Journal of Physical and Chemical Reference Data,2001,30(1):187～439.
[65]李学桓编,土壤化学[M].北京：高等教育出版社,2001,113.
[66]Hou W G, Su Y L, Sun D J, et al. Studies on zero point of charge and permanent charge density of Mg-Fe Hydrotalcite-like compounds[J]. Langmuir,2001,17(6):1885-1888.
[67]Khan A A, Singh R P. Adsorption thermodynamics of carbofuran on Sn(IV) arsenosilicate in H+, Na+ and Ca2+ forms[J]. Colloid and Surfaces,1987,24(1):33～42.
[68]Jnr M H, Spiff A I. Effects of temperature on the sorption of Pb2+ and Cd2+ from aqueous solution by Caladium bicolor (Wild Cocoyam) biomass[J]. Electronic Journal of Biotechnology,2005,8(2):162～169.
[69]Singh T S, Pant K K. Equilibrium, kinetics and thermodynamic studies for adsorption of As(Ⅲ) on activated alumina[J]. Separation and Purification Technology,2004,36(2): 139～147.
[70]Ho Y S. Review of second-order models for adsorption systems [J]. Journal of Hazardous Materials B,2006,136(3):681～689.
[71]Ho Y S, McKay G. Pseudo-second order model for sorption processes[J]. Process Biochemistry,1999,34(5):451～465.
[72]Biswas K, Bandhoyapadhyay D, ChandGhosh U. Adsorption kinetics of fluoride on iron(Ⅲ)-zirconium(IV) hybridoxide[J]. Adsorption,2007,13(1):83～94.
[73]Ayoob S, Gupta A K. Sorptive response profile of an adsorbent in the defluoridation of drinking water[J]. Chemical Engineering Journal,2007,113(1-3):273～281.
[74]Fluhler H, Polomski J, Blaser P. Retention and movement of fluorine in soils[J]. J. Environ. Qual.,1982,11(3):461～468.
[2]Wang W Y, Li R B, Luo K L. Adsorption and leaching of fluoride in soils and its health impact[J]. Fluoride,2002,35(2):122～129.
[3]Wu D S, Zheng B S, Wang A M, et al. Fluoride exposure from burning coal-clay in Guizhou Province, China[J]. Fluoride,2004,37(1):20～27.
[4]陈国阶,余大富编.环境中的氟[M].北京：科学出版社,1990.
[5]Wu W H, Xie Z M, Xu J M, et al. Characteristics of Forms of Fluorine in Soils and Influential Factors[J]. Environmental Science,2002,23(2):104～108.
[6]Samson H R. Fluoride adsorption by clay minerals and hydrated aluminum[J]. Clay minerals Bulletin,1952:266～271.
[7]Huang P M, Jackson M L. Mechanism of reaction of neutral fluoride solution with layer silicates and oxides of soils[J]. Soil Sci. Soc. Amer. Proc.,29(1965):661～665.
[8]Romo L A. Role of lattice hydroxyls in phosphate fixation and their replacement by fluoride[J]. J. Colloid Chem.,1954,9(5):385～392.
[9]Kau P M H, Smith D W, Binning P. Expterimental sorption of fluoride by kaolinite and bentonite[J]. Geoderma,1998,84(1-3):89～108.
[10]Weerasooriya R, Wickramarathne H U S, Dharmagunawardhane H A. Surface complexation modeling of fluoride adsorption onto kaolinite[J]. Colloids and Surfaces A: Physicochemical and Engineering Aspects,1998,144(1-3):267～273.
[11]Semmens B, Meggy A B. The reation of kaolin with fluorides I. Effect of neutral and acid sodium fluoride solutions[J]. J. appl. Chem.,1966,16(4):122～125.
[12]He Q, Chen J F. Preliminary study on release of hydroxo group from surface of soil colloids[J]. Acta Pedology Sinica,1984,21(4):401～409.
[13]Bower C A, Hatcher J T. Adsorption of fluoride by soils and minerals[J]. Soil Science,1967, 103(3):151～154.
[14]Harrington L F, Cooper E M, Vasudevan D. Fluoride sorption and associated aluminum release in variable charge soils[J]. Journal of Colloid and Interface Science,2003,267(2): 302～313.
[15]Wang H H, Zhu M X, Jiang X, et al. Interaction of fluoride with red soil and its environmental implications[J]. Journal of Agro-Environment Science,2006,25(4): 974～978.
[16]Barrow N J, Shaw T C. The slow reactions between soil and anions:6. Effect of time and temperature of contact on fluoride[J]. Soil Science,1977,124(5):265～278.
[17]Koppelman E H, Emerson A B, Dillard J G. Adsorbed Cr(Ⅲ) on chlorite, illite, and kaolinite:an X-ray photoelectron spectroscopic study[J]. Clays and Clay Minerals,1980, 28(2):119～124.
[18]Koppelman M H, Dillard J G. A study of the adsorption of Ni(Ⅱ) and Cu(Ⅱ) by clay minerals[J]. Clay and Clay Minerals,25(1977):457～462.
[19]Koppelman M H, Dillard J G. Adsorpation of Cr(NH3)63+ and Cr(en)33+ on clay minerals and the characterization of chromium by x-ray photoelectron spectroscopy[J]. Clays and clay minerals,1980,28(3):211～216.
[20]Koppelman M H, Dillard J G. An X-ray photoelectron spectroscopic(XPS) study of cobalt adsorbed on the clay mineral chlorite[J]. Journal of Colloid and Interface Science,1978, 66(2):345～351.
[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[J] Carsologica Sinica.1999,18(2): 109～115.
[22]Islam M, Patel R K. Evaluation of removal efficiency of fluoride from aqueous solution using quick lime[J]. Journal of Hazardous Materials,2007,143(1-2):303～310.
[23]Nigussie W, Zewge F, Chandravanshi B S. Removal of excess fluoride from water using waste residue from alum manufacturing process[J]. Journal of Hazardous Materials,2007, 147(3):954～963.
[24]Gopal V, Elango K P. Equilibrium, kinetic and thermodynamic studies of adsorption of fluoride onto plaster of Paris[J]. Journal of Hazardous Materials,2007,141(1):98～105.
[25]Mameri N, Lounici H, Belhocine D, et al. Defluoridation of Sahara water by small plantelectrocoagulation using bipolar aluminium electrodes [J]. Separation and Purification Technology,2001,24(1-2):113～119.
[26]Hichour M, Persin F, Sandeaux J, et al. Fluoride removal from waters by Donnan dialysis[J]. Separation and Purification Technology,2000,18(1):1～11.
[27]Edmunds M, Smedley P. Fluoride in Natural Waters-occurrence, controls and health aspects, Essentials of Medical Geology:Impacts of the Natural Environment on Public Health[M]. Amsterdam:Elsevier Acadamy Press,2005,301～329.
[28]Daifullah A A M, Yakout S M, Elreefy S A. Adsorption of fluoride in aqueous solutions using KMnO4-modified activated carbon derived from steam pyrolysis of rice straw[J]. Journal of Hazardous Materials,2007,147(1-2):633～643.
[29]Maliyekkal S M, Sharma A K, Philip L. Manganese-oxide-coated alumina:A promising sorbent for defluoridation of water[J]. Water Research,2006,40(19):3497～3506.
[30]Meenakshi S, Viswanathan N. Identification of selective ion-exchange resin for fluoride sorption[J]. Journal of Colloid and Interface Science,2007,308(2):438～450.
[31]Hamdi N, Srasra E. Removal of fluoride from acidic wastewater by clay mineral:Effect of solid-liquid ratios[J]. Desalination,2007,206(1-3):238～244.
[32]Das N, Pattanaik P, Das R. Defluoridation of drinking water using activated titanium rich bauxite[J]. Journal of Colloid and Interface Science,2005,292(1):1～10.
[33]Zevenbergen C, van Reeuwijk L P, Frapporti G, et al. A simple method for defluoridation of drinking water at village level by adsorption on Ando soil in Kenya[J]. The Science of the Total Environment,1996,188(2-3):225～232.
[34]Sundaram C S, Viswanathan N, Meenakshi S. Defluoridation chemistry of synthetic hydroxyapatite at nanoscale:Equilibrium and kinetic studies[J]. Journal of Hazardous Materials,2008,155(1-2):206～215.
[35]Lv L, He J, Wei M, et al. Treatment of high fluoride concentration water by MgAl-CO3 layered double hydroxides:Kinetic andequilibrium studies[J]. Water Research,2007,41(7): 1534～1542.
[36]Li Y H, Wang S G, Zhang X F, et al. Adsorption of fluoride from water by aligned carbon nanotubes[J]. Materials Research Bulletin,38(2003):469～476.
[37]Maliyekkal S M, Shukla S, Philip L, et al. Enhanced fluoride removal from drinking water by magnesia-amended activated alumina granules[J]. Chemical Engineering Journal,2008, 140(1-3):183～192.
[38]Tripathy S S, Raichur A M. Abatement of fluoride from water using manganese dioxide-coated activated alumina[J]. Journal of Hazardous Materials,2008,153(3): 1043～1051.
[39]Ghorai S, Pant K K. Equilibrium, kinetics and breakthrough studies for adsorption of fluoride on activated alumina[J]. Separation and Purification Technology,2005,42(3): 265～271.
[40]Tripathy S S, Bersillon J L, Gopal K. Removal of fluoride from drinking water by adsorption onto alum-impregnated activated alumina[J]. Separation and Purification Technology,2006,50(3):310～317.
[41]Ku Y, Chiou H M. The adsorption of fluoride ion from aqueous solution by activated alumina[J]. Water, Air, and Soil Pollution,2002,133(1-4):349～361.
[42]谭冈训,李满,武道吉,等.武城县除氟水厂的设计与运行[J].给水排水,2008,34(3)：25～27.
[43]Water quality-Determination of fluoride-Ion selective elecrode method[S]. GB7484-87,北京：中国标准出版社,1987.
[44]Dickman S R, Bray R H. Replacement of adsorbed phosphate from kaolinite by fluoride[J]. Soil Science,1941,52(4):263～273.
[45]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[J]. Clay Minerals,8(1970):325～335.
[46]Chemical reagents-Preparations of reagent solutions for use in test methods[S]. GB/T603-2002,北京：中国标准出版社,2002.
[47]Orleans R B C, Durand Y, Narjoux B, et al. LaSurface Database in Thermofisher Scientific [DB/OL]. http://www.lasurface.com/accueil/index.php.
[48]Wagner C D, Naumkin A V, Kraut-Vass A, et al. NIST X-ray Photoelectron Spectroscopy Database[DB/OL]. http://srdata.nist.gov/xps/Default.aspx,2003.
[49]Nordin J P, Sullivan D J, Phillips B L, et al. Mechanisms for fuoride-promoted dissolution of bayerite [(3-Al(OH)3(s)] and boehmite[γ-AlOOH]:19F-NMR spectroscopy and aqueous surface chemistry[J]. Geochimica et Cosmochimica Acta,1999,63(21):3513～3524.
[50]Pulfer K, Schindler P W, Westall J C, et al. Kinetics and Mechanism of Dissolution of Bayerite (y-AI(OH)3) in HNO3-HF Solutions at 298.2°K[J]. Journal of Colloid and Interface Science,1984,101(2):554～564.
[51]Parfitt R L, Russel J D. Adsorption on hydrous oxides:4. Mechanisms of adsorption of various ions on geothite[J]. Journal of Soil Science,1977,28(2):297～305.
[52]Hiemstra T, van Riemsdijk W H. Fluoride adsorption on goethite in relation to different types of surface sites[J]. Journal of Colloid and Interface Science,2000,225(1):94～104.
[53]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[J]. Geochimica et Cosmochimica Acta,1997,61(15): 3041～3049.
[54]Elrashidi M A, Lindsay W L. Chemical equilibria of fluorine in soils:a theoretical development[J]. Soil Science,1986,141(4):274～280.
[55]Wang Y X, Reardon E J. Activation and regeneration of a soil sorbent for defluoridation of drinking water[J]. Applied Geochemistry,2001,16(5):531～539.
[56]Su T Z, Guan X H, Gu G W, et al. Adsorption characteristics of As(V), Se(IV), and V(V) onto activated alumina:Effects of pH, surface loading, and ionic strength[J]. Journal of Colloid and Interface Science,2008,326(2):347～353.
[57]Porter J F, McKay G, Choy K H. The prediction of sorption from a binary mixture of acidic dyes using single- and mixed-isotherm variants of the ideal adsorbed solute theory[J]. Chemical Engineering Science,1999,54(24):5863～5885.
[58]Ayoob S, Gupta A K. Insights into isotherm making in the sorptive removal of fluoride from drinking water[J]. Journal of Hazardous Materials,2008,152(3):976～985.
[59]Tang Y L, Guan X H, Su T Z, et al. Fluoride adsorption onto activated alumina:Modeling the effects of pH and some competing ions[J]. Colloids and Surfaces A:Physicochem. Eng. Aspects,2009,337(1-3):33～38.
[60]Sujana M G, Thakur R S, Rao S B. Removal of Fluoride from Aqueous Solution by Using Alum Sludge[J]. Journal of colloid and interface science,1998,206(1):94～101.
[61]Ramanaiah S V, Mohan S V, Sarma P N. Adsorption removal of fluoride from aqueous phase using waste fungus (Pleurotus ostreatus 1804) biosorbent: Kinetics evaluation[J]. Ecological Engineering,2007,31(1):47～56.
[62]Tor A. Removal of fluoride from an aqueous solution byusing montmorillonite[J]. Desalination,2006,201(1-3):267～276.
[63]Mandal S, Mayadevi S. Adsorption offluoride ions by Zn-Al layered double hydroxides[J]. Applied Clay Science,2008,40(1-4):54～62.
[64]Site A D. Factors affecting sorption of organic compounds in natural sorbent/water systems and sorption coefficients for selected pollutants:A review[J]. Journal of Physical and Chemical Reference Data,2001,30(1):187～439.
[65]李学桓编,土壤化学[M].北京：高等教育出版社,2001,113.
[66]Hou W G, Su Y L, Sun D J, et al. Studies on zero point of charge and permanent charge density of Mg-Fe Hydrotalcite-like compounds[J]. Langmuir,2001,17(6):1885-1888.
[67]Khan A A, Singh R P. Adsorption thermodynamics of carbofuran on Sn(IV) arsenosilicate in H+, Na+ and Ca2+ forms[J]. Colloid and Surfaces,1987,24(1):33～42.
[68]Jnr M H, Spiff A I. Effects of temperature on the sorption of Pb2+ and Cd2+ from aqueous solution by Caladium bicolor (Wild Cocoyam) biomass[J]. Electronic Journal of Biotechnology,2005,8(2):162～169.
[69]Singh T S, Pant K K. Equilibrium, kinetics and thermodynamic studies for adsorption of As(Ⅲ) on activated alumina[J]. Separation and Purification Technology,2004,36(2): 139～147.
[70]Ho Y S. Review of second-order models for adsorption systems [J]. Journal of Hazardous Materials B,2006,136(3):681～689.
[71]Ho Y S, McKay G. Pseudo-second order model for sorption processes[J]. Process Biochemistry,1999,34(5):451～465.
[72]Biswas K, Bandhoyapadhyay D, ChandGhosh U. Adsorption kinetics of fluoride on iron(Ⅲ)-zirconium(IV) hybridoxide[J]. Adsorption,2007,13(1):83～94.
[73]Ayoob S, Gupta A K. Sorptive response profile of an adsorbent in the defluoridation of drinking water[J]. Chemical Engineering Journal,2007,113(1-3):273～281.
[74]Fluhler H, Polomski J, Blaser P. Retention and movement of fluorine in soils[J]. J. Environ. Qual.,1982,11(3):461～468.