簡易檢索 / 詳目顯示

研究生: 曾浩然
Chang, Hou-In
論文名稱: 兩種吸附劑去除水中磷酸鹽之研究
Removal of dissolved phosphate using two adsorbents
指導教授: 林財富
Lin, Tsair-Fuh
學位類別: 碩士
Master
系所名稱: 工學院 - 環境工程學系
Department of Environmental Engineering
論文出版年: 2009
畢業學年度: 97
語文別: 英文
論文頁數: 87
中文關鍵詞: 吸附擴散磷酸鹽Phoslock針鐵礦
外文關鍵詞: Adsorption, diffusion, goethite, Phoslock, phosphate
相關次數: 點閱:113下載:5
分享至:
查詢本校圖書館目錄 查詢臺灣博碩士論文知識加值系統 勘誤回報
  • 在台灣大部分水庫中,磷酸鹽為控制藍綠細菌生長之營養鹽。 本研究利用兩種吸附劑,分別為實驗室合成之針鐵礦及商業用之Phoslock,對磷酸鹽進行吸附動力及平衡吸附之探討。
    動力實驗結果顯示,兩種吸附劑在12小時內達到平衡,約在1小時達到平衡吸附量之一半,可以看出吸附速率很快。在pH=7.0及9.0條件下,針鐵礦之吸附量分別為21.2和11.9 mg P/g;而Phoslock分別為9.9和8.9 mg P/g 。在pH = 7.0情況下,針鐵礦之吸附量為 Phoslock兩倍,而在pH=9.0,兩種吸附劑之吸附量相近。平衡實驗顯示出兩種吸附劑對磷酸鹽的吸附量隨著 pH增加而減少。
    針鐵礦會隨著pH上升之表面界達電位變成負值,與磷酸鹽離子產生排斥現象。Phoslock受pH影響較少,主要因為pH會影響鑭與磷酸鹽生成沉澱物。在吸附平衡模式部分,Freundlich模式較適合模擬兩種吸附劑對磷酸鹽吸附之等溫吸附實驗結果。
    研究中並應用孔隙擴散模式結合Freundlich等溫吸附模式,成功模擬磷酸鹽在兩種吸附劑中之吸附動力實驗數據。在pH=7.0及9.0條件下,針鐵礦最佳化之孔隙擴散係數分別為2.0×10-8 cm2/s和2.5×10-8 cm2/s;而Phoslock為2.0×10-7 cm2/s和7.5×10-8 cm2/s。為了探討在現地吸附磷酸鹽之可行性,將針鐵礦固定於不織布袋子中進行吸附實驗,結果顯示固定化後之針鐵礦吸附量少於粉末狀,主要可能因為粉末阻塞不織布袋子孔隙及許多顆粒集結造成之質傳阻力,造成實驗時間中還沒達到平衡所致。

    關鍵字: 吸附、擴散、針鐵礦、Phoslock、磷酸鹽

    Phosphate is a limited nutrient for the growth of cyanobacteria in many Taiwan’s reservoirs. In this study, a laboratory-synthesized adsorbent (goethite) and a commercially available adsorbent (Phoslock) were used to remove phosphate from water. Kinetic and equilibrium experiments were carried out to study the adsorption of phosphate onto these two adsorbents.
    For both adsorbents, the time to reach equilibrium was all within 12 hours. About half of the capacities were saturated within 1 hour of adsorption, suggesting a relatively rapid kinetics initially. At the two pHs tested, 7.0 and 9.0, the adsorption capacities were 21.2 and 11.9 mg P/g for goethite, respectively, and were 9.9 and 8.9 mg P/g for Phoslock, respectively. At pH = 7.0, the adsorption capacity of goethite was twice higher than that of Phoslock, while at pH=9.0, their adsorption capacity were similar. Experimental data revealed that the phosphate uptake decreased with increasing equilibrium pH. For goethite, this is because the net surface charge turned to negative at higher pH, causing repulsion of the phosphate anions. For Phoslock, the effect is smaller, and is mainly caused by the effect of pH on lanthanum phosphate precipitation.
    The equilibrium adsorption data were well fitted with the Freundlich isotherm equation. A pore-diffusion model (PDM) combined with the Freundlich equation was employed to simulate the phosphate adsorption kinetics. The best fitted pore diffusion coefficients (Dp) for goethite was very similar at t two different pH conditions, 2.0×10-8 cm2/s and 2.5×10-8 cm2/s, and was 2.0×10-7 cm2/s and 7.5×10-8 cm2/s for Phoslock. On the application side, goethite immobilized in non-woven fabric bags, was used to study the feasibility of in-situ adsorption of phosphate in water. The results showed the adsorption capacities were slightly lower than those from goethite particles. It may be attributed to mass transfer limitation of the bag fabrics and particles, and the equilibrium may not be established within the experimental time.

    Keywords: Adsorption; diffusion; goethite; Phoslock; phosphate

    CONTENTS 摘要 I ABSTRACT II ACKNOWLEDGEMENT IV CONTENTS V TABLE CONTENTS VII FIGURE CONTENTS VIII CHAPTER 1 INTRODUCTION 1 1.1 Background 1 1.2 Research Objectives 2 CHAPTER 2 LITERATURE REVIEW 3 2.1 Eutrophication 3 2.1.1 Sources of nutrients 3 2.1.2 Problems of eutrophication 5 2.1.3 Control phosphorus in reservoir 8 2.2 Iron oxides 9 2.3 The surface chemistry of the metal oxide 14 2.4 Phosphate adsorption onto iron oxides 17 2.5 Introduction of Phoslock 19 2.6 Adsorption and adsorption model 21 2.7 Kinetic adsorption model 23 CHAPTER 3 MATERIALS AND METHODS 25 3.1 Chemicals 26 3.2 Adsorbents 26 3.3 Analysis and Apparatus 29 3.3.1 Surface Structure and Properties 29 3.3.2 The stabilities of goethite in acid/base solution 30 3.3.3 The sedimentation velocity of Phoslock 30 3.3.4 Preparation and Analysis o Phosphate Solution 32 3.4 Adsorption Experiments 33 CHAPTER 4 RESULTS AND DISCUSSION 35 4.1 Surface Properties 35 4.1.1 The SEM micrographs 35 4.1.2 Results of X-ray diffractometer 44 4.1.3 Specific surface area 47 4.1.4 Zeta potential 49 4.1.5 The particle size distribution of two adsorbents 51 4.1.6 The stabilities of goethite in acid/base solution 53 4.1.7 The settling velocity of Phoslock 54 4.2 Adsorption experiments 56 4.2.1 Adsorption kinetics 56 4.2.2 Adsorption isotherms 59 4.2.3 Simulation of pore-diffusion model (PDM) for adsorption kinetic data 62 4.3 Adsorption experiment of immobilized goethite 70 4.4 Adsorption experiments of both adsorbents with a background electrolyte 73 CHAPTER 5 CONCLUSIONS AND SUGGESTIONS 79 5.1 Conclusions 79 5.2 Suggestions 80 REFERENCES 81 TABLE CONTENTS Table 2.1 The water qualities of twenty reservoirs in Taiwan in 2000 to 2008 7 Table 2.2 Iron oxides (Cornell and Schwertmann, 1996) 10 Table 2.3 General properties of the iron oxides 12 Table 2.4 Point of zero charge of the minerals (Sparks, 1995) 16 Table 4.1 The amount of dissolved iron in different pH 53 Table 4.2 Parameters of Freundlich and Langmuir equation 61 Table 4.3 Properties of two adsorbents 63 Table 4.4 Extracted pore diffusion coefficients and average error between the experiment data for two adsorbents 65 FIGURE CONTENTS Figure 2.1 The phosphorous cycle in the environment (Manahan, 1994) 4 Figure 2.2 The transformation of phosphorous in land and water (Reddy et al., 1999) 5 Figure 2.3 Different species of phosphate under acidic and basic conditions (Bohn et al., 1985) 8 Figure 2.4 Formation and transformation pathway of iron oxides (Cornell and Schwertmann, 1996) 11 Figure 2.5 The cross-section of the surface layer of a metal oxide. (a) unhydrated surface (b) contact with water (c) a hydroxylated surface (Sparks, 1995) 16 Figure 3.1 Experiment procedure 25 Figure 3.2 Non-woven fabric bag 27 Figure 3.3 Goethite immobilized by non-woven fabric bag 28 Figure 3.4 A schematic chart of the column for sedimentation test 31 Figure 3.5 The correlation between Phoslock concentration and turbidity 32 Figure 3.6 The calibration curve of phosphate 33 Figure 4.1 SEM micrograph of goethite (5000 times) 36 Figure 4.2 SEM micrograph of goethite (10000 times) 36 Figure 4.3 SEM micrograph of goethite (20000 times) 37 Figure 4.4 SEM micrograph of goethite (Gotic, 2007) 37 Figure 4.5 The SEM/EDS mapping of goethite before adsorption 38 Figure 4.6 The SEM/EDS mapping of goethite after adsorption 38 Figure 4.7 SEM micrograph of Phoslock (1000 times) 40 Figure 4.8 SEM micrograph of Phoslock (5000 times) 40 Figure 4.9 SEM micrograph of Phoslock (10000 times) 41 Figure 4.10 SEM micrograph of bentonite (Putra et al., 2009) 41 Figure 4.11 The SEM/EDS mapping of Phoslock before adsorption 42 Figure 4.12 The SEM/EDS mapping of Phoslock after adsorption 43 Figure 4.13 XRD pattern of goethite 45 Figure 4.14 XRD pattern of goethite (Lin, Z. and Robert W., 2003) 45 Figure 4.15 XRD pattern of Phoslock 46 Figure 4.16 XRD pattern of bentonite (Dimirkou et al., 2002) 46 Figure 4.17 Nitrogen adsorption and desorption isotherm curves of goethite 48 Figure 4.18 Nitrogen adsorption and desorption isotherm curves of Phoslock 48 Figure 4.19 The Zeta potential of goethite at different pHs 50 Figure 4.20 The Zeta potential of Phoslock at different pHs 50 Figure 4.21 Particle size distribution of goethite 52 Figure 4.22 Change of particle size distribution for Phoslock at different time 52 Figure 4.23 The changing of turbidity at different time of the column test 55 Figure 4.24 The distribution of Phoslock concentration and settling velocity 55 Figure 4.25 Adsorption kinetics of phosphate on goethite at pH 7 and pH 9 (Initial concentration=1 mg P/L) 58 Figure 4.26 Adsorption kinetics of phosphate on Phoslock at pH 7 and pH 9 (Initial concentration=1 mg P/L) 58 Figure 4.27 Experimental data of goethite fitted by Langmuir and Freundlich isotherms 60 Figure 4.28 Experimental data of Phoslock fitted by Langmuir and Freundlich isotherms 61 Figure 4.29 Simulated PDM and experimental data for the adsorption of phosphate onto goethite 64 Figure 4.30 Simulated PDM and experimental data for the adsorption of phosphate onto Phoslock 64 Figure 4.31 (a)-(d) Prediction of the adsorption kinetics for the adsorption of phosphate adsorption onto Phoslock with different volumes 69 Figure 4.32 SEM micrograph of goethite that trapped on the fabric (500 times) 71 Figure 4.33 SEM micrograph of goethite that trapped on the fabric (5000 times) 71 Figure 4.34 Adsorption kinetic of phosphate on the immobilized goethite at pH 7 and pH 9 (Initial concentration=1 mg P/L) 72 Figure 4.35 Adsorption isotherms of phosphate on the immobilized goethite at pH 7 and pH 9 72 Figure 4.36 Adsorption kinetics of phosphate on goethite in 0.01N KNO3 at pH 7 and pH 9 (Initial concentration=1 mg P/L) 74 Figure 4.37 Adsorption kinetics of phosphate on Phoslock in 0.01N KNO3 at pH 7 and pH 9 (Initial concentration=1 mg P/L) 75 Figure 4.38 Adsorption isotherm of phosphate on goethite in different concentration of background electrolyte at pH 7 and pH 9 77 Figure 4.39 Adsorption isotherm of phosphate on Phoslock in different concentration of background electrolyte at pH 7 and pH 9 78

    Aligizaki, K.K., 2006. Pore Structure of Cement-Based Materials: Testing, Interpretation and Requirements. Taylor & Francis, UK.

    Antelo, J., Avena, M., Fiol, S., López, R., Arce, F., 2005. Effects of pH and ionic strength on the adsorption of phosphate and arsenate at the goethite–water interface. J. Colloid and Interface Science 285, pp. 476-486.

    Bartram, J., Carmichael, W.W., Chorus, I., Jones, G., Skulberg, O.M., 1999. Introduction. In Toxic cyanobacteria in water: a guide to their public health consequences, monitoring, and management, E and FN Spon Publishers., pp. 291-320, WA.

    Bohn, H.L., Mcneal, B.L., O’connor, G.A., 1985. Soil Chemistry. John Wiley, New York.

    Brunauer, S., Emmett, P.H., Teller, E., 1938. Adsorption of gases in multimolecular layers. J. American Chemical Society 60, pp. 309-319.

    Catarino, S., Madeira, M., Monteiro, F., Rocha, F., Curvelo-Garcia, A.S., and Bruno de Sousa, R., 2008. Effect of bentonite characteristics on the elemental composition of wine. J. Agric. Food Chem. 56, pp. 158-165.

    Celi, L., Barberis, E., Marsan, F. A., 2000. Sorption of phosphate on goethite at high concentrations. Soil Science. 165, pp. 657-664.
    Chang, S.P., Chuang, S.M., 2001. Eutrophication study of twenty reservoirs in Taiwan. Wat. Sci. Tech. 44, pp. 19-26.

    Chitrakar, R., Tezuka, S., Sonoda, A., Sakane, K., Ooi, K. Hirotsu, T., 2006. Phosphate adsorption on synthetic goethite and akaganeite. J. Colloid and Interface science 298, pp. 602-608.

    Chorus, I., Mur, L., 1999. Preventative measures. In Toxic cyanobacteria in water: a guide to their public health consequences, monitoring, and management. E and FN Spon Publishers, pp. 291-320, WA.

    Cornell, R.M., Schwertmann, U., 1996. The Iron Oxide: Structure, properties, reactions, occurrence and uses, Wiley-VCH, New York.

    Dimirkou, A., Ioannoub, A., Doula, M., 2002. Preparation, characterization and sorption properties for phosphates of hematite, bentonite and bentonite_hematite systems. Adv. in Colloid and Interface Sci. 97, pp. 37-61.

    Douglas G.B., Robb M.S., Coad D.N., Ford P.W., 2004. A review of solid phase adsorbents for the removal of phosphorus from natural waste waters. In “Phosphorus in environmental technology: principles and applications”, Valsami-Jones E., pp. 291-320, WA.

    Falconer, I.R., 2005. Cyanobacterial toxins of drinking water supplies: cylindrospermopsins and microcystins, CRC Press, Boca Raton, FL., US.

    Firsching, F.H., Brune, S.N., 1991. Solubility products of the trivalent rare-earth phosphates. J. Chem. Engng. Data 36, pp.93-95

    Geelhoed, J.S., Hiemstra, T., Van Riemsdijk, W.H., 1997. Phosphate and sulfate adsorption on goethite: Single anion and competitive adsorption. Geochimica et Cosmochimica Acta 61, pp. 2389-2396.

    Gotic, M., Music, S., 2007. Mössbauer, FT-IR and FE SEM investigation of iron oxides precipitated from FeSO4 solutions. J. Molecular Structure, 834-836, pp. 445-453.

    Harper, D., 1992. Eutrophication of Freshwaters—Principles, Problems and Restoration. Chapman and Hall, New York.

    Harter, R.D., Smith, G., 1981. Langmuir equation and alternate methods of studying “adsorption” reactions in soils. In Chemistry in the soil environment (Dowdy, R.H., Ryan, J.A., Volk, V.V., Baker, D.E., eds), Am. Soc. Agron. Spec. Publ. No 40, pp. 167-182. Am. Soc. Agron. / Soil Sci. Soc. Am., Madison, WI

    House, J., Ho, L., Newcombe, G., Burch, M., 2005. Strategies and Practices for Management of Toxic Blue-Green Algae: A Guide. Australian Water Quality Centre, Cooperative Research Centre for Water Quality and Treatment.

    Jun, H.B., Lee, Y.J., Lee, B.D., Knappe, D.R.U., 2001. Effectiveness of coagulants and coagulant aids for the removal of filter-clogging Synedra. J. Wat. Supply: Research and Technology - AQUA 50, pp. 135-148.

    Lam, A.K.Y., Prepas, E.E., Spink, D., 1995. Chemical control of hepatotoxic phytoplankton blooms: implications for human health. Wat. Res. 29, pp. 1845-1854.

    Li, L., Stanforth, R., 2000. Distinguishing adsorption and surface precipitation of phosphate on goethite (α-FeOOH). J. Colloid and Interface Science 230, pp. 12-21.

    Lin, T.F., Little, J.C., Nazaroff, W.W., 1996. Transport and sorption of organic gases in activated carbon. J. Environ. Engng. 122, pp. 169-175

    Lin, T.F., Wu, J.K., 2001. Adsorption of arsenite and arsenate within activated alumina grains: equilibrium and kinetics. Wat. Res. 35, pp. 2049-2057.

    Lin, Z., Robert, W., 2003. Potential indicators for the assessment of arsenic natural attenuation in the subsurface. Adv. in Environ. Res. 7, pp. 825-834.

    Luengo, C., Brigante M., Antelo J., Avena M., 2006. Kinetics of phosphate adsorption on goethite: Comparing batch adsorption and ATR-IR measurements. J. Colloid and Interface Science 300, pp. 511-518.

    Makris, K.C., El-Shall, H., Harris, W.G., O'Connor, G.A., Obreza, T.A., 2004. Intraparticle phosphorus diffusion in a drinking water treatment residual at room temperature. J. Colloid and Interface Science 277, pp. 417-423.

    Manahan, S.E., 1994. Environmental Chemistry. Lewis Punlishs, Boca Raton, FL.

    Mezenner, N.Y., Bensmaili, A., 2009. Kinetics and thermodynamic study of phosphate adsorption on iron hydroxide-eggshell waste. Chem. Engng. J. 147, pp. 87–96.

    Mohamedelhassan, E., Shang, J.Q., 2001. Analysis of electrokinetic sedimentation of dredged Welland River sediment. J. Hazardous Materials 85, pp. 91-109.

    Ning, P., Bart, H.J., Li, B., Lu, X., Zhang, Y., 2008. Phosphate removal from wastewater by model-La(III) zeolite adsorbents. J. Env. Sci. 20, pp. 670-674.

    Ou, E.C., Zhou, J.J., Mao, S.C., Wang, J.Q., Xia F., Min, L., 2007. Highly efficient removal of phosphate by lanthanum-doped mesoporous SiO2. Colloids Surf. 308, pp. 47-53.

    Peterson, S. A., Sanville, W.D., Stay, F.S., Powers, C.F., 1976. Laboratory Evaluation of Nutrient Inactivation Compounds for Lake Restoration. J. Wat. Pollution Control Federation 48, pp. 817-831.

    Plummer, J.D., Edzwald, J.K., 2001. Effect of ozone on algae as precursors for trihalomethane and haloacetic acid production. Environ. Sci. Technol. .35, pp.3661-3668.

    Putra, E.K., Pranowo, R., Sunarso, J., Indraswati, N., Ismadji, S., 2009. Performance of activated carbon and bentonite for adsorption of amoxicillin from wastewater: Mechanisms, isotherms and kinetics. Wat. Res. 43, pp. 2419-2430.

    Reddy, K.R., Kadlec, R. H., Flaig, E., Gale, P.M., 1999. Phosphorous retention in streams and wetlands-A review. Critical Reviews in Environmental Science and Technology 29, pp. 86-146.

    Ross, G., Haghseresht, F., Cloete, T.E., 2008. The effect of pH and anoxia on the performance of Phoslock ®, a phosphorus binding clay. Harmful Algae 7, pp.545-550.

    Shin, E.W., Karthikeyan, K.G., Tshabalala, M.A., 2005. Orthophosphate sorption onto lanthanum-treated lignocellulosic sorbents. Environ. Sci. Technol. 39, pp. 6273-6279.

    Sparks, D.L., 1995. Environmental Soil Chemistry. Harcourt Brace and Company, San Diego, CA.

    Strauss, R., Brümmer, G.W., Barrow, N.J., 1997. Effects of crystallinity of goethite: II. Rates of sorption and desorption of phosphate. European Journal of Soil Science 48, pp. 101-114.

    Stumm, W., Morgan, J.J., 1981. Aquatic Chemistry, John Wiley & Sons Inc

    Tian, S., Jiang, P., Ning, P., Su, Y., 2009. Enhanced adsorption removal of phosphate from water by mixed lanthanum/aluminum pillared montmorillonite. Chem. Engng. J. 151, pp. 141-148.

    Tokunaga, S., Yokoyama, S., Wasay, S.A., 1999. Removal of Arsenic (III) and Arsenic (V) compounds from aqueous solutions with lanthanum (III) salt, and comparison with aluminum (III), calcium (III) and iron (III) salts. Wat. Environ. Res. 71, pp. 299-306.

    Torrent, J., 1997. Interactions between phosphate and iron oxide. Adv. in Geoecology 30, pp. 321-344.

    Wakao, N., Funazkri, T., 1978. Effect of fluid dispersion coefficients on particle-to-fluid mass transfer coefficients in packed beds. Chem. Engng. Sci. 33, pp.1375-1384.

    Wasay, S.A., Haron, M.J., Tokunaga, S., 1996. Adsorption of fluoride, phosphate, and arsenate ions on lanthanum-impregnated silica gel. Wat. Environ. Res. 68, pp. 295-300.

    Wong, K.B., Piedrahita, R.H., 2000. Settling velocity characterization of aquacultural solids. Aquacultural Engng. 21, pp. 233-246.

    Wu, S.S., Lam, K.H., Lee, M.N., Lau, T.C., 2007. Removal of phosphate from water by a highly selective La(III)-chelex resin. Chemosphere 69, pp. 289-294.

    下載圖示 校內:立即公開
    校外:2009-08-11公開
    QR CODE