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Temperature effects on freshwater snail shells: Pomacea canaliculata Lamarck as investigated by XRD, EDX, SEM and FTIR techniques
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Materials Science and Engineering C 28 (2008) 316 – 319 www.elsevier.com/locate/msec
Temperature effects on freshwater snail shells: Pomacea canaliculata Lamarck as investigated by XRD, EDX, SEM and FTIR techniques N. Udomkan a,⁎, P. Limsuwan b a
b
Department of Physics, Faculty of Science, Srinakharinwirot University, Sukhumvit 23, Bangkok 10110, Thailand Department of Physics, Faculty of Science, King Mongkut's University of Technology Thonburi, Bangkok 10140, Thailand Received 11 February 2006; received in revised form 28 February 2007; accepted 1 March 2007 Available online 12 March 2007
Abstract In this study, the XRD, EDX, SEM and FTIR analyses are used for the characterization of the thermal decomposition process of Pomacea canaliculata Lamarck (PCL) samples. All these shells are abundant in Thailand. The shell was ground into fine powders. A set of four samples each was then separately annealed for 2 h in air atmosphere at 300 °C, 400 °C, 450 °C and 500 °C, respectively. The PCL shell mainly consists of aragonite and a fraction of calcite. If the PCL powder samples were annealed at a temperature higher than 450 °C, it resulted in an irreversible phase transformation from aragonite to calcite. The FTIR spectra analyses of PCL show that, after an annealing, the relative intensities of CO2− 3 absorption bands and the intensities of OH− absorption band increased. © 2007 Elsevier B.V. All rights reserved. Keywords: Freshwater snails; Aragonite; Calcite
1. Introduction As it has been reported earlier elsewhere, the CaCO3 minerals have recently taken much of interest since the carbonate minerals are the major constituent found in aquatic invertebrate exoskeletons (shells) [1–5]. Two common polymorphs of CaCO3 are aragonite (orthorhombic) and calcite (trigonal). Aragonite with a structure is less common and less stable than calcite, while calcite with trigonal symmetry is the most thermodynamically stable form of pure CaCO3 at room temperature and atmospheric pressure [6]. Apparently, metallic ions incorporated into the mineral reflect environmental factors which affected biomineralization process while the shell formation occurred. Owing to the sensitivity of Fourier transform infrared (FTIR) spectroscopy, it becomes a versatile tool to study trace of radical species, attributed to the organic matter [7] such as phase transition [8]. Since no structural analyses and
FTIR observations have been done for the freshwater Thai snail shells from the Mae Moh basin, Pomacea canaliculata Lamarck, the authors have taken up for the present investigation. P. canaliculata Lamarck have been called as pond snail or river snails which are found widespread in shallow freshwater and light saline water in Thailand such as ponds or brooks, coastal areas, gulfs and basins where the sediment is mud or sandy mud. The freshwater univalves have a single shell which spirals outward and to one side as it grows. This aquatic mollusk has been served as a nutrition protein source for people and animals, mainly, in the countryside. The purpose of the present study was to investigate in detail the effect of temperature on freshwater snail shells using the following techniques: X-ray diffraction (XRD), Fourier transform infrared (FTIR), Energy dispersive X-ray fluorescence (EDX) and Scanning electron microscopy (SEM) of freshwater snail shells in the temperature range of 300–500 °C. 2. Experimental procedure
⁎ Corresponding author. E-mail address: [email protected] (N. Udomkan). 0928-4931/$ - see front matter © 2007 Elsevier B.V. All rights reserved. doi:10.1016/j.msec.2007.03.001
The present-day exoskeletons of freshwater snail, P. canaliculata Lamarck (PCL) living in the freshwater habitat in
N. Udomkan, P. Limsuwan / Materials Science and Engineering C 28 (2008) 316–319
317
Fig. 1. Powder XRD patterns of Pomacea canaliculata Lamarck samples (a) unannealed, (b) annealed at 400 °C and (c) annealed at 500 °C (⁎referred to calcite phase.).
Thailand, were obtained through a reliable agent. The specimens were cleaned by soaking in dilute sodium hydroxide solution for several hours, followed by washing thoroughly with distilled water to wash out of the soft part remains in the shell including stains and other impurities on the shells' surface. The PCL samples are now called as untreated PCL denoted by PCL-00. The cleaned samples were then ground into fine powder and used as received. The effects of heat treatment on the crystal structure of the PCL shells were investigated by annealing separately four powder samples in an air atmosphere at 300 °C, 400 °C, 450 °C and 500 °C for 2 h; the series of samples are denoted by PCL-300, PCL-400, PCL-450 and PCL-500, respectively. The effects of heat treatment on the crystal structure of PCL shells were investigated by X-ray powder diffractrometer (XRD). The X-ray diffraction patterns were recorded at room temperature using a Bruker diffractometer, Model D8 Advanced [CuKα (Ni-filtered) with scintillation detector; 2θ range 20–70°; step size 0.0194°; data collection time 12 h]. The FTIR spectra were performed on Perkin Elmer FTIR spectrometer, Model PE 2000 in the wavenumber region 400–4000 cm− 1. All FTIR measurements were carried out at room temperature using the KBr pellet technique. Meanwhile, microstructures of unheated products were obtained by using a scanning electron microscope (SEM), (Jeol-LMS-6400 with 300 EDX facilities). The as-sintered samples were fixed on the brass stubs, coated with Pt and Pd by sputtering for ohmic contact and viewed under the SEM. The sintered samples were cut into thin discs of about 1 mm thick and 1 cm in diameter. They were polished by SiC paper and alumina powder to obtain smooth surface and cleaned discs were electroded by screening paste on both sides.
3. Results and discussions 3.1. X-ray diffractograms Fig. 1 displays the powder X-ray diffraction patterns of P. canaliculata Lamarck before and after heat treatments at different temperatures. For the heat treatment at a temperature higher than 400 °C, the XRD patterns show the phase transition from aragonite to calcite. At an annealed temperature of 500 °C, it is a pure calcite phase only, suggesting that the phase transition is complete. By sintering at 900 °C, the fluffy, very white powder, pure phase CaO was formed, which resulted from the well known decomposition of carbonate at high temperature [9]. Meanwhile, five samples of P. canaliculata Lamarck were chosen to determine trace elements and the results are shown in Table 1. It is clear that on average, these samples contain CaCO3, MgO, Al2O3 and SiO2, 92.68, 1.68, 1.04 and 4.29% wt, respectively. Furthermore, the heat treatment will also improve the crystal clarity and at the same time the phase transforms from aragonite to calcite. Table 1 EDX analysis of P. canaliculata Lamarck by weight percent Samples
CaCO3
MgO
Al2O3
SiO2
PCL-1 PCL-2 PCL-3 PCL-4 PCL-5 Average
92.4 92.80 92.90 92.80 92.50 92.68
1.60 1.80 1.70 1.70 1.60 1.68
1.05 1.01 1.03 1.10 1.02 1.04
4.29 4.25 4.30 4.28 4.31 4.29
318
N. Udomkan, P. Limsuwan / Materials Science and Engineering C 28 (2008) 316–319
Fig. 2. FTIR spectra of freshwater snail shell; (a) PCL-500, (b) PCL-450, (c) PCL-400, (d) PCL-300 and (e) PCL-00.
3.2. FTIR spectra The infrared spectra of P. canaliculata Lamarck powder are shown in Fig. 2. It is seen that, the absorption bands of CO32− are observed at the wavenumber 1797, 1799, 1416, 1032, 874, 876, 712 and 535 cm− 1 which are the common feature of the CO32− ions in CaCO3. The bands in the range of 874–876 cm− 1 can be assigned to ν2(A2) mode. The absorption bands in the range of 1390–1416 cm− 1 is assigned to ν3(E) mode of CO32− ion and the absence of infrared inactive mode ν1(A1). The bands in the range of 3585–3697 cm− 1 suggest that these bands are due to the presence of water content. The band at 1032 cm− 1 corresponds to ν1(A1) mode of the CO32− ions in aragonite group. The appearance of a doubly degenerate band at 712 cm− 1, can be assigned to ν1(E) mode of CO32−. The absorption band around 3400–3600 cm− 1 arises from stretching vibration of structure water molecules [10]. The absorption band of water molecules decreases with increasing temperature and disappears at 400 °C. On the other hand, at 500 °C, a sharp OH− stretching band at
3621 cm− 1 was observed. From FTIR spectroscopy studies, it was concluded that between 300 °C to 500 °C the relative intensities of CO32− absorption bands decreased and the intensity of OH− absorption band increased. 3.3. SEM analysis The surface morphologies of freshwater snail shell for outer and inner surfaces were observed by a scanning electron microscope and the results are shown in Fig. 3 (a) and (b), respectively. However, some voids were also observed at these surfaces. The grain size tended to increase from the inner surface to the outer surface. 4. Conclusion In this study, the XRD, EDX, SEM and FTIR analyses are used for the characterization of the effects of temperature on freshwaters snail shell samples. The heat treatment of
N. Udomkan, P. Limsuwan / Materials Science and Engineering C 28 (2008) 316–319
319
the PLC powder samples has caused an irreversible phase transformation from aragonite to calcite within the CaCO3 lattice. We conclude that P. canaliculata Lamarck crystal structure is pure calcite (CaCO3) when heated at a temperature above 500 °C in air atmosphere for 2 h. Acknowledgements N. Udomkan wishes to thank the University Development Committee (UDC) from Srinakharinwirot University for the financial support to make this research possible. References
Fig. 3. The surface morphologies of freshwater snail shell (a) outer surface and (b) inner surface.
[1] N.E Pingitore Jr., M.P. Eastman, M. Sandidge, K. Oden, B. Freiha, Mar. Chem. 25 (1988) 107. [2] C.P. Lakshmi Prasuna, K.V. Narasimhulu, N.O Gopal, J. Lakshmana Rao, T.V.R.K Rao, Spectrochim. Acta A 60 (2004) 2305. [3] H.S. Sullasi, M.B Andrade, W.E.F. Ayta, M. Frade, M.D Sastry, S. Watanabe, Nucl. Instrum. Methods Phys. Res., B Beam Interact. Mater. Atoms 213 (2004) 756. [4] B. Hasse, H. Eherenberg, J.C. Marxen, W. Becker, M. Epple, Chem. Eur. J. 6 (2000) 3679. [5] G.T. Faust, Am. Mineral. 35 (1950) 207. [6] J. Perić, M. Vučak, R. Krstulovič, Lj. Brečević, D. Kralj, Thermochim. Acta 277 (1996) 175. [7] R.N. Clark, AGU Handbook of Physical Constant, 1995, p. 178. [8] K. Suito, J. Namba, T. Horikawa, Y. Taniguchi, N. Sakurai, M. Kobayashi, A. Onodera, O. Shimomura, T. Kikegawa, Am. Mineral. 86 (2001) 997. [9] N. Passe-Coutrin, Ph. N'Guyen, R. Pelmard, A. Quensanga, C. Bouchon, Thermochim. Acta 265 (1995) 135. [10] V. Michel, Ph. Ildefonse, G. Morin, Palaeogeography 126 (1996) 109.
Materials Science and Engineering C 28 (2008) 316 – 319 www.elsevier.com/locate/msec
Temperature effects on freshwater snail shells: Pomacea canaliculata Lamarck as investigated by XRD, EDX, SEM and FTIR techniques N. Udomkan a,⁎, P. Limsuwan b a
b
Department of Physics, Faculty of Science, Srinakharinwirot University, Sukhumvit 23, Bangkok 10110, Thailand Department of Physics, Faculty of Science, King Mongkut's University of Technology Thonburi, Bangkok 10140, Thailand Received 11 February 2006; received in revised form 28 February 2007; accepted 1 March 2007 Available online 12 March 2007
Abstract In this study, the XRD, EDX, SEM and FTIR analyses are used for the characterization of the thermal decomposition process of Pomacea canaliculata Lamarck (PCL) samples. All these shells are abundant in Thailand. The shell was ground into fine powders. A set of four samples each was then separately annealed for 2 h in air atmosphere at 300 °C, 400 °C, 450 °C and 500 °C, respectively. The PCL shell mainly consists of aragonite and a fraction of calcite. If the PCL powder samples were annealed at a temperature higher than 450 °C, it resulted in an irreversible phase transformation from aragonite to calcite. The FTIR spectra analyses of PCL show that, after an annealing, the relative intensities of CO2− 3 absorption bands and the intensities of OH− absorption band increased. © 2007 Elsevier B.V. All rights reserved. Keywords: Freshwater snails; Aragonite; Calcite
1. Introduction As it has been reported earlier elsewhere, the CaCO3 minerals have recently taken much of interest since the carbonate minerals are the major constituent found in aquatic invertebrate exoskeletons (shells) [1–5]. Two common polymorphs of CaCO3 are aragonite (orthorhombic) and calcite (trigonal). Aragonite with a structure is less common and less stable than calcite, while calcite with trigonal symmetry is the most thermodynamically stable form of pure CaCO3 at room temperature and atmospheric pressure [6]. Apparently, metallic ions incorporated into the mineral reflect environmental factors which affected biomineralization process while the shell formation occurred. Owing to the sensitivity of Fourier transform infrared (FTIR) spectroscopy, it becomes a versatile tool to study trace of radical species, attributed to the organic matter [7] such as phase transition [8]. Since no structural analyses and
FTIR observations have been done for the freshwater Thai snail shells from the Mae Moh basin, Pomacea canaliculata Lamarck, the authors have taken up for the present investigation. P. canaliculata Lamarck have been called as pond snail or river snails which are found widespread in shallow freshwater and light saline water in Thailand such as ponds or brooks, coastal areas, gulfs and basins where the sediment is mud or sandy mud. The freshwater univalves have a single shell which spirals outward and to one side as it grows. This aquatic mollusk has been served as a nutrition protein source for people and animals, mainly, in the countryside. The purpose of the present study was to investigate in detail the effect of temperature on freshwater snail shells using the following techniques: X-ray diffraction (XRD), Fourier transform infrared (FTIR), Energy dispersive X-ray fluorescence (EDX) and Scanning electron microscopy (SEM) of freshwater snail shells in the temperature range of 300–500 °C. 2. Experimental procedure
⁎ Corresponding author. E-mail address: [email protected] (N. Udomkan). 0928-4931/$ - see front matter © 2007 Elsevier B.V. All rights reserved. doi:10.1016/j.msec.2007.03.001
The present-day exoskeletons of freshwater snail, P. canaliculata Lamarck (PCL) living in the freshwater habitat in
N. Udomkan, P. Limsuwan / Materials Science and Engineering C 28 (2008) 316–319
317
Fig. 1. Powder XRD patterns of Pomacea canaliculata Lamarck samples (a) unannealed, (b) annealed at 400 °C and (c) annealed at 500 °C (⁎referred to calcite phase.).
Thailand, were obtained through a reliable agent. The specimens were cleaned by soaking in dilute sodium hydroxide solution for several hours, followed by washing thoroughly with distilled water to wash out of the soft part remains in the shell including stains and other impurities on the shells' surface. The PCL samples are now called as untreated PCL denoted by PCL-00. The cleaned samples were then ground into fine powder and used as received. The effects of heat treatment on the crystal structure of the PCL shells were investigated by annealing separately four powder samples in an air atmosphere at 300 °C, 400 °C, 450 °C and 500 °C for 2 h; the series of samples are denoted by PCL-300, PCL-400, PCL-450 and PCL-500, respectively. The effects of heat treatment on the crystal structure of PCL shells were investigated by X-ray powder diffractrometer (XRD). The X-ray diffraction patterns were recorded at room temperature using a Bruker diffractometer, Model D8 Advanced [CuKα (Ni-filtered) with scintillation detector; 2θ range 20–70°; step size 0.0194°; data collection time 12 h]. The FTIR spectra were performed on Perkin Elmer FTIR spectrometer, Model PE 2000 in the wavenumber region 400–4000 cm− 1. All FTIR measurements were carried out at room temperature using the KBr pellet technique. Meanwhile, microstructures of unheated products were obtained by using a scanning electron microscope (SEM), (Jeol-LMS-6400 with 300 EDX facilities). The as-sintered samples were fixed on the brass stubs, coated with Pt and Pd by sputtering for ohmic contact and viewed under the SEM. The sintered samples were cut into thin discs of about 1 mm thick and 1 cm in diameter. They were polished by SiC paper and alumina powder to obtain smooth surface and cleaned discs were electroded by screening paste on both sides.
3. Results and discussions 3.1. X-ray diffractograms Fig. 1 displays the powder X-ray diffraction patterns of P. canaliculata Lamarck before and after heat treatments at different temperatures. For the heat treatment at a temperature higher than 400 °C, the XRD patterns show the phase transition from aragonite to calcite. At an annealed temperature of 500 °C, it is a pure calcite phase only, suggesting that the phase transition is complete. By sintering at 900 °C, the fluffy, very white powder, pure phase CaO was formed, which resulted from the well known decomposition of carbonate at high temperature [9]. Meanwhile, five samples of P. canaliculata Lamarck were chosen to determine trace elements and the results are shown in Table 1. It is clear that on average, these samples contain CaCO3, MgO, Al2O3 and SiO2, 92.68, 1.68, 1.04 and 4.29% wt, respectively. Furthermore, the heat treatment will also improve the crystal clarity and at the same time the phase transforms from aragonite to calcite. Table 1 EDX analysis of P. canaliculata Lamarck by weight percent Samples
CaCO3
MgO
Al2O3
SiO2
PCL-1 PCL-2 PCL-3 PCL-4 PCL-5 Average
92.4 92.80 92.90 92.80 92.50 92.68
1.60 1.80 1.70 1.70 1.60 1.68
1.05 1.01 1.03 1.10 1.02 1.04
4.29 4.25 4.30 4.28 4.31 4.29
318
N. Udomkan, P. Limsuwan / Materials Science and Engineering C 28 (2008) 316–319
Fig. 2. FTIR spectra of freshwater snail shell; (a) PCL-500, (b) PCL-450, (c) PCL-400, (d) PCL-300 and (e) PCL-00.
3.2. FTIR spectra The infrared spectra of P. canaliculata Lamarck powder are shown in Fig. 2. It is seen that, the absorption bands of CO32− are observed at the wavenumber 1797, 1799, 1416, 1032, 874, 876, 712 and 535 cm− 1 which are the common feature of the CO32− ions in CaCO3. The bands in the range of 874–876 cm− 1 can be assigned to ν2(A2) mode. The absorption bands in the range of 1390–1416 cm− 1 is assigned to ν3(E) mode of CO32− ion and the absence of infrared inactive mode ν1(A1). The bands in the range of 3585–3697 cm− 1 suggest that these bands are due to the presence of water content. The band at 1032 cm− 1 corresponds to ν1(A1) mode of the CO32− ions in aragonite group. The appearance of a doubly degenerate band at 712 cm− 1, can be assigned to ν1(E) mode of CO32−. The absorption band around 3400–3600 cm− 1 arises from stretching vibration of structure water molecules [10]. The absorption band of water molecules decreases with increasing temperature and disappears at 400 °C. On the other hand, at 500 °C, a sharp OH− stretching band at
3621 cm− 1 was observed. From FTIR spectroscopy studies, it was concluded that between 300 °C to 500 °C the relative intensities of CO32− absorption bands decreased and the intensity of OH− absorption band increased. 3.3. SEM analysis The surface morphologies of freshwater snail shell for outer and inner surfaces were observed by a scanning electron microscope and the results are shown in Fig. 3 (a) and (b), respectively. However, some voids were also observed at these surfaces. The grain size tended to increase from the inner surface to the outer surface. 4. Conclusion In this study, the XRD, EDX, SEM and FTIR analyses are used for the characterization of the effects of temperature on freshwaters snail shell samples. The heat treatment of
N. Udomkan, P. Limsuwan / Materials Science and Engineering C 28 (2008) 316–319
319
the PLC powder samples has caused an irreversible phase transformation from aragonite to calcite within the CaCO3 lattice. We conclude that P. canaliculata Lamarck crystal structure is pure calcite (CaCO3) when heated at a temperature above 500 °C in air atmosphere for 2 h. Acknowledgements N. Udomkan wishes to thank the University Development Committee (UDC) from Srinakharinwirot University for the financial support to make this research possible. References
Fig. 3. The surface morphologies of freshwater snail shell (a) outer surface and (b) inner surface.
[1] N.E Pingitore Jr., M.P. Eastman, M. Sandidge, K. Oden, B. Freiha, Mar. Chem. 25 (1988) 107. [2] C.P. Lakshmi Prasuna, K.V. Narasimhulu, N.O Gopal, J. Lakshmana Rao, T.V.R.K Rao, Spectrochim. Acta A 60 (2004) 2305. [3] H.S. Sullasi, M.B Andrade, W.E.F. Ayta, M. Frade, M.D Sastry, S. Watanabe, Nucl. Instrum. Methods Phys. Res., B Beam Interact. Mater. Atoms 213 (2004) 756. [4] B. Hasse, H. Eherenberg, J.C. Marxen, W. Becker, M. Epple, Chem. Eur. J. 6 (2000) 3679. [5] G.T. Faust, Am. Mineral. 35 (1950) 207. [6] J. Perić, M. Vučak, R. Krstulovič, Lj. Brečević, D. Kralj, Thermochim. Acta 277 (1996) 175. [7] R.N. Clark, AGU Handbook of Physical Constant, 1995, p. 178. [8] K. Suito, J. Namba, T. Horikawa, Y. Taniguchi, N. Sakurai, M. Kobayashi, A. Onodera, O. Shimomura, T. Kikegawa, Am. Mineral. 86 (2001) 997. [9] N. Passe-Coutrin, Ph. N'Guyen, R. Pelmard, A. Quensanga, C. Bouchon, Thermochim. Acta 265 (1995) 135. [10] V. Michel, Ph. Ildefonse, G. Morin, Palaeogeography 126 (1996) 109.