Malaysian Journal of Analytical Sciences Vol 24 No 1 (2020): 1 - 10

 

 

 

PREPARATION AND CHARACTERISATION OF pH PROBE MEMBRANE FOR DETERMINATION OF TOTAL ALKALINITY IN SEAWATER

 

(Penyediaan dan Pencirian Membran Prob pH bagi Penentuan Jumlah Kealkalian dalam Air Laut)

 

Noor Sheryna Jusoh, Azrilawani Ahmad*, Marinah Mohd Ariffin, Hafiza Mohamed Zuki

 

Faculty of Science and Marine Environment,

Universiti Malaysia Terengganu, 21030 Kuala Nerus, Terengganu, Malaysia

 

*Corresponding author:  azrilawani.ahmad@umt.edu.my

 

 

Received: 20 November 2019; Accepted: 16 January 2020

 

 

Abstract

A pH probe membrane was successfully synthesised using polyvinyl chloride (PVC), chromoionophore I (CI), different additives (KTFPB and ETH500), plasticiser 2-nitrophenyl octyl ether (NPOE) and tetrahydrofuran (THF). Membrane casting method was applied during the preparation of the membrane. In order to evaluate the performance of the functional PVC membrane, physical characterisation such as scanning electron microscopy (SEM), attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), ultraviolet-visible spectroscopy (UV-Vis), fluorescence spectroscopy and tensile strength were conducted. Electrochemical characterisation was carried out using glassy carbon (GC) and gold (Au) electrodes, in order to identify the presence of electroactive species and to examine the behaviour of the membrane under electrochemical environment. The voltammetric measurement was conducted in 2.5 mM ferricyanide/ferrocyanide in 0.1 M KCl redox probe, at potential range of -0.2 - +0.6 V with the scan rate of 50 mV/s. The performance of PVC membrane using different additives was compared and analysed.

 

Keywords:  polymeric functional membrane, PVC, voltammetry, total alkalinity

 

Abstrak

Membran prob pH telah berjaya disintesis menggunakan polivinil klorida (PVC), kromoionofor I (CI), aditif yang berbeza (KTFPB dan ETH500), pemplastik 2-nitrofenil oktil eter (NPOE) dan tetrahidrofuran (THF). Kaedah penuangan membran telah diaplikasi semasa penyediaan membran. Bagi menilai prestasi membran PVC berfungsi, pencirian fizikal seperti mikroskopi elektron pengimbasan (SEM), pantulan keseluruhan dikecilkan-spektroskopi inframerah jelmaan Fourier (ATR-FTIR), spektroskopi ultralembayung-nampak (UV-Vis), spektroskopi pendafluoran dan kekuatan tensil telah dijalankan. Pencirian elektrokimia telah dilakukan menggunakan elektrod karbon berkaca (GC) dan emas (Au), untuk menentukan kehadiran spesis elektroaktif dan menguji tindakan membran di bawah persekitaran elektrokimia. Pengukuran voltametri telah dilakukan dalam 2.5 mM ferisianida/ferosianida dalam 0.1 M KCl prob redoks, pada julat keupayaan -0.2 V - +0.6 V dengan kadar imbasan 50 mV/s. Prestasi membran PVC menggunakan aditif yang berbeza telah dibandingkan dan dianalisa.

 

Kata kunci:  membran polimerik berfungsi, PVC, voltametri, jumlah kealkalian

 

References

1.       Lohbeck, K. T., Riebesell, U. and Reusch T. B. H. (2012). Adaptive evolution of a key phytoplankton species to ocean acidification. Nature Geoscience, 5: 346-351.

2.       Anthony, K. R. N., Kleypas, J. A. and Gattuso, J. P. (2011). Coral reefs modify their seawater carbon chemistry- implications for impacts of ocean acidification. Global Change Biology, 17(12): 3655-3666.

3.       Dickson, A. G., Sabine, C. L. and Christian, J. R. (2007). Guide to best practices for ocean CO₂ measurement. North Pacific Marine Science Organization, Sidney, British Columbia: pp. 191.

4.       Crespo, G. A., Afshar, M. G. and Bakker, E. (2012). Direct detection of acidity, alkalinity and pH with membrane electrodes. Analytical Chemistry, 84(23): 10165-10169.

5.       Byrne, R. H. (2014). Measuring ocean acidification: New technology for a new era of ocean chemistry. Environmental Science & Technology, 48: 5352-5360.

6.       Riebesell, U. F., Victoria, J., Hansson, L. and Gattuso, Jean-Pierre (2011). Guide to best practices for ocean acidification research and data reporting. Office for Official Publications of the European Communities, Luxembourg: pp 258.

7.       Spaulding, R. S., DeGrandpre, M. D., Beck., J. C., Hart., R. D., Peterson, B., De Carlo, E. H., Drupp, P. S. and Hammar, T. R. (2014). Autonomous in situ measurements of seawater alkalinity. Environmental Science and Technology, 48(16): 9573-9581.

8.       Afshar, M. G., Waeber, M. L. T., Wehrli, B. and Bakker, E. (2017). Direct sensing of total alkalinity profile in a stratified lake. Geochemistry Perspectives Letters, 3: 85-93.

9.       Tan, X. M. and Rodrigue, D. (2019). A review on porous polymeric membrane preparation. Part 1: Production techniques with polysulfone and poly (vinylidene fluoride). Polymers, 11: 1-39.

10.    Ulbricht, M. (2006). Advances functional polymer membranes. Polymer, 47(7): 2217-2262.

11.    Ren, J. and Wang, R. (2010). Preparation of polymeric membranes. Membrane and Desalination Technologies, Handbook of Environmental Engineering, 13: 47-100.

12.    Vihali, C. and Vaum, N. (2012). Use of plasticizers for electrochemical sensors: Recent advances in plasticisers. Intech Open: pp. 125-140.

13.    Othman, M. A. F., Ahmad, A. and Zuki, H. M. (2016). Dithizone modified electrode for the determination of metals ion in aqueous solution. Malaysian Journal of Analytical Sciences, 20(1): 197-204.

14.    Carey, C. (2015). Plasticizer effects in the PVC membrane of the dibasic phosphate selective electrode. Chemosensors, 3: 284-294.

15.    Lalia, B. S., Kockodan, V., Hashaikeh, R. and Hilal, N. (2013). A review on membrane fabrication: Structure, properties and performance relationship. Desalination, 326: 77-95.

16.    Fadilah, N. I. M. and Hassan, A. R. (2016). Preparation, characterization and performance studies of active PVDF ultrafiltration-surfactants membranes containing PVP as additive. Malaysia Journal of Analytical Sciences, 20(2): 335-341.

17.    Zhang, Y.J., Lin, R., and Yuan, M.Y. (2013). Effects of Pore-Forming Additives on Structures and Properties of PVDF/Fe3+/Cu2+ Hollow Fiber Membranes. Desalination. Water Treat, 51: 3903–3908.

18.    Tooma, M. A., Najim, T. S., Alsalhy, Q. S., Marino, T., Criscuoli, A., Giorno, L. and Figoli, A. (2015). Modification of polyvinyl chloride (PVC) membrane for vacuum membrane distillation (VMD) application. Desalination, 373: 58-70.

19.    Ismayil, K. M. M., Manaf, O., Sujith, A. and Antony, R. (2019). Polymer thin films for chromatographic separation of plant pigments. Materials Letters, 252: 321-324.

20.    Yu, Q. and Selvadurai, A. P. S. (2005). Mechanical behaviour of plasticized PVC subjected to ethanol exposure. Polymer Degradation and Stability, 89: 109-124.

21.    Das, P. and Ray, S. K. (2016). Pervaporative recovery of tetrahydrofuran from water with plasticized and filled polyvinyl chloride membranes. Journal of Industrial and Engineering Chemistry, 34: 321-336.