International Journal of Civil Engineering and Technology (IJCIET) Volume 9, Issue 9, September 2018, pp. 1246–1255, Article ID: IJCIET_09_09_120 Available online at http://iaeme.com/Home/issue/IJCIET?Volume=9&Issue=9 ISSN Print: 0976-6308 and ISSN Online: 0976-6316
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A REVIEW ON ADSORPTION OF NICKEL AND MERCURY FROM AQUEOUS SOLUTION USING NANOPARTICLES
Dr. K.R. Aswin Sidhaarth Associate Professor, Department of Civil Engineering, Vel Tech Rangarajan & Dr.Sagunthala R & D Institute of Science and Technology, Avadi, Chennai, Tamil Nadu, India
S. Baskar PhD Scholar & Assistant Professor, Department of Civil Engineering, Vel Tech Rangarajan & Dr.Sagunthala R & D Institute of Science and Technology, Avadi, Chennai, Tamil Nadu, India
ABSTRACT The toxic heavy metals such as cadmium, copper, lead, nickel, mercury, and zinc from aqueous environment has received considerable attention in recent years due to their toxicity and carcinogenicity. This paper focuses mainly on Nickel & Mercury which may cause damage to various systems of the human body. Mercury and Nickel ions are non-biodegradable toxic heavy metals and may cause dermatitis and allergic sensitization. The major sources of Nickel & Mercury contamination to water comes from industrial process such as electroplating, batteries manufacturing, mine, metal finishing and forging. Different methods were investigated and applied to remove nickel and mercury ions from water such as adsorption, chemical precipitation, ion exchange, filtration, membrane separation, and reverse osmosis. In this paper a detailed insight has been given on adsorption with an eye on removal of mercury and nickel using different adsorbents. Keywords: Nickel, mercury, adsorption, adsorbents. Cite this Article: Dr. K.R. Aswin Sidhaarth and S. Baskar, A Review on Adsorption of Nickel and Mercury from Aqueous Solution using Nanoparticles, International Journal of Civil Engineering and Technology, 9(9), 2018, pp. 1246–1255. http://iaeme.com/Home/issue/IJCIET?Volume=9&Issue=9
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1. INTRODUCTION Mercury & Nickel is a highly volatile and highly toxic heavy metal present in the environment. Inorganic mercury in water is mainly seen in the +2 oxidation state. These two metal ions are released into the atmosphere through a variety of natural and anthropogenic sources. Natural sources include volcanic eruptions, mercury rich soil and forest fires. Mobilization of mercury from fossil fuels, incinerators, chloralkali industries, gold mining, processing and refining of mercury ores are few of the major anthropogenic sources. Once released into the environment, it can undergo complex physical and chemical transformations. Released mercury vapor and nickel oxide gets converted into soluble form and gets deposited in soil and water by rain. Established separation techniques for recovery of metals from the coagulate can be used for making this a complete solution for treated water discharge in to Ocean.[2] Adsorption is widely used because it is cost-effective and simple. Different adsorbents such as seaweeds, crab shell , dried aerobic activated sludge , loof sponge-immobilized biomass of chlorella sorokiniana , activated carbon prepared from almond husk, spent animal bones, and waste factory tea have been used to remove nickel ions from aqueous water, but low adsorption capacities or efficiencies limit their applications. Therefore, investigating new adsorbents with higher adsorption capacities and efficiencies has been the aims of many researchers. [13] The current study is a benign effort to deal with Nickel and Mercury generated as industrial and mining effluents discharged into the environment. Nickel and Mercury compounds are widely used in industries such as electroplating, metal finishing, leather tanning, pigments etc and therefore the effluents of these industries contain lead and zinc in suitable concentrations.
2. NICKEL AND MERCURY – METALS OF CONCERN
2.1. NICKEL Nickel is a chemical element with symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel belongs to the transition metals and is hard and ductile. Pure nickel, powdered to maximize the reactive surface area, shows a significant chemical activity, but larger pieces are slow to react with air under standard conditions because an oxide layer forms on the surface and prevents further corrosion (passivation). Even so, pure native nickel is found in Earth's crust only in tiny amounts, usually in ultramafic rocks, and in the interiors of larger nickel–iron meteorites that were not exposed to oxygen when outside Earth's atmosphere. Nickel is slowly oxidized by air at room temperature and is considered corrosion- resistant. Historically, it has been used for plating iron and brass, coating chemistry equipment, and manufacturing certain alloys that retain a high silvery polish, such as German silver. About 9% of world nickel production is still used for corrosion-resistant nickel plating.[13] In our study a humble attempt will be made for the removal of nickel from aqua-stream using calcium based nano particle by performing batch, column and modelling study.
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2.2. MERCURY Mercury is a chemical element with symbol Hg and atomic number 80. It is commonly known as quicksilver and was formerly named hydrargyrum from where the symbol Hg is arrived. This is the heavy silvery d-block element, mercury is the only metallic element that is liquid at standard conditions for temperature and pressure, The only other element that is liquid under these conditions is bromine, though metals such as caesium, gallium, and rubidium melt just above room temperature. Mercury occurs in deposits throughout the world mostly as cinnabar (mercuric sulfide). The red pigment vermilion is obtained by grinding natural cinnabar or synthetic mercuric sulfide. Removing mercury from the water can be achieved using four processes: Coagulation/Filtration, Granular Activated Carbon, Lime Softening, and Reverse Osmosis. Coagulation/filtration is a common treatment which uses AlSO4 that reacts with the mercury to form a solid which can precipitate out of the water. Mercury contamination is a widespread problem, not just locally but also globally, and its serious effects on health are well known. Mercury in the environment comes from many sources: it is transported by wind and rain from local and global emission sources, it can be present in urban and industrial wastewater, and it can be naturally occurring in soils and springs, particularly in the Costal zones.[2] In our study a humble attempt will be made for the removal of Mercury from aqua-stream using calcium based nano particle by performing batch, column and modelling study.
3. NANOMATERIALS IN WASTEWATER TREATMENT As a result of their size, nano-materials can exhibit an array of unique novel properties which can be utilized in development of new heavy metal and dye treatment technologies and improvement of existing ones. Some of their properties, such as high surface area, self assembly, high specificity, and other properties make them an excellent candidate for removal of heavy metals and dyes from wastewater by adsorption. In our work we are going to work on calcium based Nanoparticles for the removal of mercury and nickel from aqueous solutions by adopting top-down approach for synthesis followed by batch, column and modelling studies.
4. STUDY AREA – A SNAPSHOT The encroachments have reduced the depth and the spread of the Ennore Creek. Once a famed fishing ground with a rich diversity of commercially valuable fish, prawns and crab, the Ennore Creek is gasping for life. Fishing economy has been badly hit, and once self- sufficient fisher folk families in Mugatwarakuppam, Sivanpadai Kuppam and Kattukuppam have been reduced to poverty.
4.1. Flooding In December 2015, areas like Kuruvimedu, Athipattu, Athipattu Pudunagar, Ernavur, Manali New Town, Kodungaiyur, Vyasarpadi, Tondiarpet, Korukkupet — located in the assembly constituencies of Madhavaram, Ponneri, R.K. Nagar and Thiruvottiyur — were badly affected by floodwaters because of the encroachments in Ennore Creek.
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4.2. Storm Surges In December 2016, Cyclone Vardah made landfall in the Ennore region. The resultant storm surge of more than 1 metre above the astronomic tide inundated low-lying areas in the region. Normally, the Creek is the first shock absorber to deter the storm surge. But with its water carrying capacity vastly reduced, the Creek’s ability to absorb storm shocks has also declined. As the encroachment continues, storm surges will send seawater deep into the Ocean.
4.3. Contributors for surface water Pollution in Ennore Creek Belt
5. A DETAILED INSIGHT
5.1. Adsorption Principles and Practices Adsorption is the attachment of molecules or particles to a surface. The surface may be a part of any solid matter, but some are more effective than others. Molecules that adsorb are largely organic, and include both natural and synthetic. Adsorption occurs extensively in the natural environment. Random contacts between molecules and particles occur throughout the hydrologic cycle and in many kinds of aquatic systems. For engineered adsorption systems, the context for ―contacts‖ is a reactor and the solid is usually an adsorbent.
5.2. Adsorption Procedure -Nickel Dillon et al (2000) [13] performed batch adsorption experiments, 1000 mg/l stock solutions prepared from analytical reagent grade of Ni(NO3)2 6H2O in deionized water. The solution was further diluted to the required concentrations (from 10 to 200 mg/l) before used. Initial pH was adjusted by diluted hydrochloric acid and diluted sodium hydroxide. All the experiments were per- formed by agitating 50 ml of the nickel solution at the desired concentration and 20 mg surface water in 100 ml bottles. Agitation was performed for a predetermined time at room temperature in a reciprocating shaker. The suspension was filtered through 0.45 µm for calcium carbonated shell filters and the nickel was determined in
http://iaeme.com/Home/journal/IJCIET 1249 [email protected] Dr. K.R. Aswin Sidhaarth and S. Baskar the liquid phase using atomic absorption spectrophotometer. The amount of nickel adsorbed was obtained using the following equation
Qe = ((Co-Ce)*V)/w
where qe is the equilibrium uptake (mg/g), C0 is the initial nickel ion concentration (mg/l), Ce is the equilibrium nickel ion con- centration (mg/l), V is the volume of the solution (l) and w is the mass of the adsorbent (g).
Ref TEM image for (a) as-produced coagulate, (b) Ionized solvent[13] Vijayaraghavan et al (2004) [6] Multi-walled carbon nanotubes (MWCNTs) were produced by chemical vapor decomposition using acetylene gas in the presence of Ferrocene catalyst at 800 ◦C, and then oxidized with concentrated nitric acid at 150◦C. Both (as- produced and oxidized) CNTs were characterized by TEM, Boehm titration, N2-BET and cation exchange capacity techniques. The adsorption capacity for nickel ions from aqueous solutions increased significantly onto the surface of the oxidized CNTs compared to that on the as-produced CNTs. Multi-walled carbon nanotubes (MWCNTs) used in this work were produced by catalytic decomposition of acetylene gas (as a hydrocarbon source) in the presence of Ferrocene (as a cat- alyst) and nitrogen gas at 800 ◦C. Al-Asheh, et al (1999) [9] The aim of the research work is a new application of Polypyrrole and its composites with bentonite for removing of heavy metal ions. The conducting polypyrrole composites were prepared by oxidation in presence of FeCl3. It was found that the polypyrrole composites can be used as an effective adsorbent in the removal of Pb (II) from wastewater under specific conditions. The effect of various parameters such as pH of solution, dosages of adsorbent contect time and initial concentration of metal ion solution were investigated. Also the adsorbent were characterized by Fourier transform infrared spectrometer (FTIR) and analyzed by atomic absorption spectrophotometer (AAS) device. Here detailed review has been given related to the work carried out by Dillon et al (2000) [13] The Ionization treatment for Aqua solvent has improved the adsorption uptake of nickel ions significantly as shown in Fig. 2. The maximum adsorption uptake for the Ionizion reaches 38 mg/g at equilibrium Ni2+ concentration of 74 mg/l, compared to 12.5 mg/g for the as-produced Calcium nano materials at equilibrium Ni2+ con- centration of 175 mg/l. This significant adsorption improvement is expected due to the presence of the different functional groups formed on the CNMs surface during the oxidation, which also improved their hydrophilic and cation exchange properties. In addition to the presence of the functional groups, the increase in the Ionized CNMs specific surface area (Table 1) supports the higher adsorption capability and the increase in the active adsorption sites. The larger specific
http://iaeme.com/Home/journal/IJCIET 1250 [email protected] A Review on Adsorption of Nickel and Mercury from Aqueous Solution using Nanoparticles surface area may be due to the removed amorphous carbon particles and metal catalyst in addition to the fracture caused by oxidation on their surface. This is also clear from the cation exchange capacity differences between the as-produced and Ionized CNMs, which was found as 110 meq./100-g CNTs and 253 meq./100-g CNMs, respectively.
Table 1 Characteristic of the as-produced and Ionized CNMs Ionization intensity (meq./100g Surface Area (m2/g) CNMs) As Produced CNMs 132 118 Active Ionization 145 250
Figure 2 Effect of equilibrium concentration on the adsorption uptake of nickel [13]
5.3. Adsorption Procedure -Mercury
5.3.1. Preparation for Reagents (Chemical)
Tetrachloroauric acid trihydrate (HAuCl4.3H2O) Trisodium citrate and sodium borohydride (NaBH4)A stock solution of 500 mg/L Hg(II) was prepared from HgCl2 required concentrations were made by serial dilution. Magnesium oxide, neutral activated alumina (140 mesh, 150 m2/g) was from a local source and used as received. Triple distilled water was used throughout the experiment.
5.3.2. Instrumentation UV-vis absorption spectra were performed on a spectrometer. Low mercury concentrations (<0.2 mg/L) in the solutions were detected by a Mercury Analyzer. Mercury analyses in the concentration range of 0.21 to 2.2mg/L were done using colorimeter. Scanning electron microscopic (SEM) images and energy dispersive analysis of X-ray (EDAX) studies were done in a FEI.
5.3.3. Synthesis of supported CNMs CNMs with an average diameter of 10-20 nm were synthesized by the reduction of HAuCl4.3H2O with tri-sodium citrate. Supported CNMs were prepared by the following procedure. 10 g of neutral activated alumina were soaked in 25 mL of CNMs suspension for 480 minutes. Once the supernatant became colourless, it was replaced with another fresh 25 mL suspension. This procedure was repeated until there was no colour change for the supernatant. After decanting the supernatant, CNMs coated alumina were washed thoroughly with distilled water and dried under ambient condition
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5.3.4. Adsorption Nutt et all (2005) [37] the interaction between supported CNMs and Hg(II) ions was studied using a column set-up. 2 g of CNMs & Coagulated alumina was taken in the column and 1.0 mg/L Hg(II) solution was passed through it at a flow rate of 5 mL/minute. 5 mL of the treated water was collected at an interval of 100 mL and analysed for residual mercury using UV-vis spectroscopy [37]. The experiment was continued till mercury was detected in the treated sample. A calibration graph was drawn using known concentrations and the fabsorbance at 570 nm due to the complex formed between tetraiodomercurate for studying the interaction of supported CNMs with Hg(0), 1.0 mg/L Hg(II) was reduced with dilute aqueous NaBH4 (10 times the mercury concentration) and allowed to stand for 1 h. Afterwards, the solution was passed through a column containing 2 g of CNMs. 5 mL of the treated water was collected at an interval of 100 mL. Before analysis, the sample collected was treated with concentrated HCl for the oxidation of Hg. The experiment was continued till mercury was detected in the sample. Same experiment was repeated with 2.0 mg/L Hg(II) also. In order to find the interaction of Hg(0) with alumina, the experiment was repeated with 2 g of alumina. USEPA, Mercury Study Report to Congress (December 1997) (22) Mercury deposits on the earth in different ways and at different rates, depending on its physical and chemical form. Mercuric species are subject to much faster atmospheric removal than elemental mercury. Mercuric mercury bound to airborne particles and in a gaseous form is readily scavenged by precipitation and is also dry deposited (that is, deposited in the absence of precipitation). In contrast, elemental mercury vapour has a strong tendency to remain airborne and is not susceptible to any major process resulting in direct deposition to the earth's surface.
Source Adapted from Winfrey, M.R. and J.W.M. Rudd. 1990. Review -- Environmental Factors Affecting the Formation of Methylmercury in Low pH Lakes. Environ. Toxicol. Chem. 9:853-869. Here detailed review has been given related to the work carried out by Nisha et all (2000) [2] a study was done with 0.2 mg/L mercury for understanding the interaction of low concentrations of mercury with supported 8gms CNMs. nanoparticle-coated alumina was taken in the column and mercury solution was passed at a rate of 5 mL/minute. 50 mL of the treated water was collected at an interval of 1 L. Mercury concentration in the sample was detected using a mercury analyzer at 253.7 nm. Batch experiments were done for finding the interaction of supported gold nanoparticles with mercury. For the study, 1 g of gold nanoparticle-coated alumina was transferred to NaBH4 treated 500 mL of 1.5 mg/L Hg(II) and stirred continuously. 5 mL of the sample was collected at different time intervals and centrifuged, supernatant was collected for mercury measurement.
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Ref TEM images of CNMs nanoparticles before and after mercury treatment. (A) Large area image of CNMs nanoparticles before the reaction. (B) The corresponding lattice resolved image of a single nanoparticle. (C) Large area image of mercury treated CNMs nanoparticles. (D) The corresponding lattice resolved image of a single nanoparticle [2] The surface excess amount of the adsorbed gas (Gibbs adsorption) niσ is the excess number of moles of that substance present in the real system over the number present in a reference system, where adsorption does not appear at the same equilibrium gas pressure. The excess number of moles niσ can be calculated in the following way.
σ s g s ni =ʃ(ci -ci )dV + ʃci dV Where s g ʃ(ci -ci )dV is the adsorption space s ʃci dV is the surface layer of the adsorbent s Ci is the local concentration of substance i in a volume Element dV of the interfacial layer g Ci is the concentration of that substance in the bulk phase In our work based on the contributions made by above authors we are going to investigate on Mercury removal from aqueous solution using calcium based Nano Particles by performing initial characterization studies followed by batch column and modeling study.
6. CONCLUSION The calcium based nanoparticle supported on alumina can be a excellent system for the removal of Hg+ from water. Adsorption capacity will be studied using a column experiment and was monitored using UV-vis spectroscopy. The time dependent removal was also studied. TEM and SEM analyses can also be used for understanding the morphology of the Au-Hg system. EDAX analysis and XRD Shall confirmed the Au-Hg alloy formation. It was confirmed by control experiments that pure alumina alone is unable to remove mercury from water. Experiments revealed that the concentration of boron in the treated water is below the maximum permissible limit set by the WHO. The chemistry of metal-alloying presents a novel approach for sequestration of heavy metals. While we have studied the removal of mercury from drinking water, this study can be extended to the extraction of mercury from other sources such as industrial effluents. CNMs have been produced by Activated Ionization in the presence of Ferrocene as a catalyst. The collected powder was used to remove nickel ions from water and proved to be very effective. The oxidation of the byproduct of CNMs improved their hydrophilic
http://iaeme.com/Home/journal/IJCIET 1253 [email protected] Dr. K.R. Aswin Sidhaarth and S. Baskar properties and increased their cation exchange capacity from 118 to 250 meq./100-g CNMs due to the formation of different aqua solution groups on the CNMs surface. Langmuir parameters showed that the oxidized CNMs have greater adsorption capacity for nickel ion removal from water than that for the Clam families, shells or as-produced CNMs.
REFERENCES
[1] S.H. Lin, S.L. Lai, H.G. Leu, Removal of heavy metals from aqueous solution by chelating resin in a multistage adsorption process, J. Hazard. Mater. B76 (2000) 139–153. [2] K.P. Lisha, Anshup and T. Pradeep DST Unit on Nanoscience (DST UNS) Department of Chemistry and Sophisticated Analytical Instrument Facility, Indian Institute of Technology Madras, Chennai 600 036, India [3] F.A. Abu Al-Rub, M. Kandah, N. Al-Dabaybeh, Nickel removal from aqueous solutions using sheep manure wastes, Eng. Life Sci. 2 (2002) 111–116. [4] US EPA, Guidance Manual for Electroplating and Metal Finishing Pre- treatment Standards, 1984 [5] K. Vijayaraghavan, J. Jegan, K. Palanivelu, M. Velan, Biosorption of cobalt(II) and nickel(II) by seaweeds: batch and column studies, Sep. Purif. Technol. 44 (2005) 53–59. [6] K. Vijayaraghavan, J. Jegan, K. Palanivelu, M. Velan, Removal of nickel(II) ions from aqueous solution using crab shell particles in a packed bed up- flow column, J. Hazard. Mater. B113 (2004) 223–230. [7] Z. Aksu, D. Akpmar, Modeling of simultaneous biosorption of phenol and nickel(II) onto dried aerobic activated sludge, Sep. Purif. Technol. 21 (2000) 87–99. [8] N. Akhar, J. Iqbal, M. Iqbal, Removal and recovery of nickel(II) from aqueous solution by loofa sponge-immobilized biomass of Chlorella sorokiniana: characterization studies, J. Hazard. Mater. B108 (2004) 85–94. [9] S. Al-Asheh, F. Banat, F. Mobai, Sorption of copper and nickel by spent animal bones, Chemosphere 39 (12) (1999) 2087–2096. [10] E. Malkoc, Y. Nuhoglu, Removal of Ni(II) ions from aqueous solutions using waste of tea factory: adsorption on a fixed-bed column, J. Hazard. Mater. B135 (2006) 328–336. [11] S. Iijima, Helical microtubules of graphic carbon, Nature 354 (1991) 56–58. [12] R.Q Long, R.T. Yang, Carbon nanotubes as superior sorbent for dioxin removal, J. Am. Chem. Soc. 123 (2001) 2058–2059. [13] A.C. Dillon, K.M. Jones, T.A. Bekkedahl, C.H. Kiang, D.S. Bethune, M.I. Heben, Storage of hydrogen in single-walled carbon nanotubes, Nature 386 (1997) 377–385. [14] C.W. Bauschlicher, A. Ricca, Binding of NH3 to graphite and to a (9, 0) carbon nanotube., Phys. Rev. B 70 (2004) 115409–115413. [15] W.L. Yim, Z.F. Liu, A reexamination of the chemisorption and desorption of ozone on the exterior of a (55) single-walled carbon nanotube, Chem. Phys. Lett. 98 (2004) 297– 303. [16] W.H. Schroeder, J. Munthes, Atmos. Environ., 1998, 32, 809 [17] C.J. Lin, S.O. Pehkonen, Atmos. Environ., 1999, 33, 2067 [18] F. Zahir, S.J. Rizwi, S.K. Haq, R.H. Khan, Environ. Toxicol. Phar., 2005, 20, 351 [19] S. Ekino, M. Susa, T. Ninomiya, K. Imamura, T. Kitamura, J. Neurol. Sci., 2007, 262, 131 [20] Study Group of Minamata Disease. Minamata Disease. Kumamoto: Kumamoto University, 1968 [21] W.H.O., Guidelines for Drinking Water Quality, 3rd ed., 2004, Volume 1
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[22] USEPA, Mercury Study Report to Congress, December 1997, EPA-452/ R-97-003 [23] Dr. R.C. Srivastava, Guidance and Awareness Raising Materials under new UNEP Mercury Programs (Indian Scenario), 2004, Centre for Environmental Pollution Monitoring and Mitigation, India [24] H.G. Park, T.W. Kim, M.Y. Chae, I.K. Yoo, Process Biochem., 2007, 42, 1371 [25] V. Smuleaca, D.A. Butterfield, S.K. Sikdar, R.S. Varma, D. Bhattacharyya, [26] H. Biester, P. Schuhmacher, G. Mueller, Water. Res., 2000, 34, 2031 [27] J. Kostal, A. Mulchandani, K.E. Gropp, W. Chen, Environ. Sci. Technol., 2003, 37, 4457 [28] N. Savage, M.S. Diallo, J. Nanopart. Res., 2005, 7, 331 [29] M.S. Diallo, N. Savage, J. Nanopart. Res., 2005, 7, 325 [30] A.S. Nair, R.T. Tom, T. Pradeep, J. Environ. Monit., 2003, 5, 363 [31] A.S. Nair, T. Pradeep, J. Nanosci. Nanotechno., 2007, 7, 1 [32] A.S. Nair, T. Pradeep, Curr. Sci., 2003, 84, 1560 [33] Y. Chen, J. Qiu, X. Wang, J. Xiu, J. Catal., 2006, 242, 227 [34] G. Riahi, D. Guillemot, M.P. Thfoin, A.A. Khodadadi, J. Fraissard, Catal. Today, 2002, 72, 1 5 [35] M.R. Regan, I.A. Banerjee, Scripta Mater., 2006, 54, 909 [36] Y. Mizukoshi, T. Fujimoto, Y. Nagata, R. Oshima, Y. Maeda, J. Phys. Chem. B, 2000, 104, 6028 [37] M.O. Nutt, J.B. Hughes, M.S. Wong, Environ. Sci. Technol., 2005, 39, 1346 [38] Orlov, D.A. Jefferson, N. Macleod R.M. Lambert, Catal. Lett., 2004,92, 41 [39] M. Boronat, P. Concepcion, A. Corma, S. Gonzalez, F. Illas, P. Serna, J. Am. Chem. Soc., 2007, [40] S. Pacheco, M. Medina, F. Valencia, J. Tapia, J. Environ. Eng. ASCE, 2006, [41] W. Yantasee, C.L. Warner, T. Sangvanich, R.S. Addleman, T.G. Carter, [42] R.J. Wiaceck, G.E. Fryxell, C. Timchalk, M.G. Warner, Environ. Sci. Technol., 2007, 41, 51 4 [43] M. Mullett, J. Tardio, S. Bhargava, C. Dobbs, J. Hazard. Mater., 2007, 144, 274. [44] J. Turkevich, P.L. Stevenson, J. Hillier, Discuss Faraday Soc., 1951, 1 , 55 [45] T.V. Ramakrishna, G. Aravamudan, M. Vijayakumar, Anal. Chim. Acta, 1976, 84, 369 [46] F.J. Lopez, E. Gimenez, F. Hernandez, Fresen. J. Anal. Chem., 1993, 346, 984 [47] M.M.F.G. Soto, E.M. Camacho, Sep. Purif. Technol., 2006, 48, 36 [48] Henglein, M. Giersig, J. Phys. Chem. B, 2000, 104, 5056 [49] JCPDS (Joint Committee on Powder Diffraction Standards) Data File No. [04-0784] [50] JCPDS Data File No. [89-371 ]
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