Sains Malaysiana 45(3)(2016): 477–487

Photocatalytic Degradation of Some Charges Aqueous Phase Pollutants using Nafion and Silica Modified TiO2

(Kemusnahan Fotomangkinan Beberapa Pencemar Tercas Fasa Akueus menggunakan TiO2 Terubahsuai Nafion dan Silika)

 

CHOWDHURY, M.M.I. & VOHRA, M.S.*

 

Department of Civil and Environmental Engineering, King Fahd University of Petroleum and Minerals, Dhahran, Kingdom of Saudi Arabia 31261

 

Received: 25 December 2014/Accepted: 26 August 2015

 

ABSTRACT

The present study investigated the use of modified titanium dioxide (TiO2) based photocatalytic degradation (PCD) process for the removal of some critical charged aqueous phase pollutants. First of all, the use of Nafion TiO2 (Nf-TiO2) and silica TiO2 (Si-TiO2) for the removal of aqueous phase ammonia (NH4+/NH3) species employing near UV lamp as energy source was studied. The use of Nf-TiO2 enhanced NH4+/NH3 PCD with optimum removal noted for 1 mL of Nafion solution coating per g of TiO2 and respective overall NH4+/NH3 removal was about 1.7 times higher compared to plain TiO2 at 6 h reaction time. Similarly the 0.5 mL silica solution coating per g TiO2 sample, also enhanced NH4+/NH3 removal with optimum efficiency similar to Nf-TiO2. The results from effect of ammonia concentration on to its PCD using Nf-TiO2 indicated that overall mass based NH4+/NH3 removal was higher at greater NH4+/NH3 amounts indicating high efficiency of Nf-TiO2. Similar trends were noted for Si-TiO2 as well. Furthermore, the results from modified TiO2 and mixed NH4+/NH3 and cyanide (CN-) systems indicated successful removal of co-pollutant CN- along with simultaneous degradation of NH4+/NH3 species at rates that were still higher than plain TiO2. Nevertheless application of Nf-TiO2 for the treatment of cationic dye methylene blue (MB) indicated slower MB removal compared to plain TiO2 though significant MB degradation using Nf-TiO2 could still be achieved at pH3. Additionally the results from solar radiation energized PCD process indicated positive role of solar radiation for the removal of NH4+/NH3 species under a varying set of conditions.

Keywords: Cationic pollutants; Nafion TiO2; photocatalysis; solar energy; silica TiO2

 

ABSTRAK

Penyelidikan ini mengkaji tentang penggunaan titanium dioksida terubah suai (TiO2) berasaskan proses pemusnahan fotomangkinan (PCD) untuk sesetengah bahan pencemar tercas fasa akueus kritikal. Pertama ialah penggunaan semua TiO2 Nafion (Nf-TiO2) dan TiO2 silika (Si-TiO2) untuk penyingkiran ammonia fasa akueus spesies (NH4+/NH3) yang menggunakan lampu dekat UV sebagai sumber tenaga telah dikaji. Penggunaan Nf-TiO2 mempertingkatkan NH4+/NH3 PCD dengan penyingkiran optimum bagi 1 mL salutan penyelesaian Nafion untuk setiap g TiO2 dan keseluruhan penyingkiran NH4+/NH3 adalah 1.7 kali lebih tinggi berbanding dengan TiO2 plain pada masa tindak balas 6 jam. Lapisan larutan silika 0.5 mL untuk setiap g sampel TiO2, juga mempertingkatkan penyingkiran NH4+/NH3 dengan kecekapan optimum menyerupai Nf-TiO2. Hasil daripada kesan kepekatan ammonia kepada PCD dengan menggunakan Nf-TiO2 menunjukkan bahawa jisim keseluruhan berasaskan penyingkiran NH4+/NH3 adalah lebih tinggi daripada jumlah NH4+/NH3 yang menunjukkan kecekapan tinggi Nf-TiO2. Trend serupa dilihat pada Si-TiO2. Selain itu, hasil daripada TiO2 diubah suai dan campuran NH4+/NH3 dan sistem sianida (CN-) menunjukkan penyingkiran berjaya bersama pencemar CN- bersama-sama dengan kemerosotan serentak spesies NH4+/NH3 pada kadar yang telah masih lebih tinggi daripada TiO2 biasa. Walau bagaimanapun, aplikasi Nf-TiO2 untuk rawatan kationik pencelup metilena biru (MB) menunjukkan penyingkiran MB lebih perlahan berbanding TiO2 plain walaupun kemerosotan MB secara bererti menggunakan Nf-TiO2 masih boleh dicapai pada pH3. Tambahan pula keputusan daripada sinaran suria yang mengecas proses PCD menunjukkan peranan positif radiasi solar untuk penyingkiran spesies NH4+/NH3 di bawah satu set keadaan yang berbeza.

 

Kata kunci: Bahan pencemar kationik; fotomangkinan; tenaga solar; TiO2 Nafion; TiO2 silika

REFERENCES

 

Asahi, R., Morikawa, T., Ohwaki, T., Aoki, K. & Taga, Y. 2001. Visible-light photocatalysis in nitrogen-doped titanium oxides. Science 293(5528): 269-271.

Berne, F. & Cordonnier, J. 1995. Industrial Water Treatment: Refining, Petrochemicals, and Gas Processing Techniques. Houston: Gulf Professional Publishing.

Bonsen, E.M., Schroeter, S., Jacobs, H. & Broekaert, J.A.C. 1997. Photocatalytic degradation of ammonia with TiO2 as photocatalyst in the laboratory and under the use of solar radiation. Chemosphere 35(7): 1431-1445.

Chao, Y.M., Tseng, I.C. & Chang, J.S. 2006. Mechanism for sludge acidification in aerobic treatment of coking wastewater. Journal of Hazardous Materials 137(3): 1781- 1787.

Choi, W. 2006. Pure and modified TiO2 photocatalysts and their environmental applications. Catalysis Surveys from Asia 10(1): 16-28.

Chen, K.T., Lu, C.S., Chang, T.H., Lai, Y.Y., Chang, T.H., Wu, C.W. & Chen, C.C. 2010. Comparison of photodegradative efficiencies and mechanisms of Victoria Blue R assisted by Nafion-coated and fluorinated TiO2 photocatalysts. Journal of Hazardous Materials 174(1-3): 598-609.

Collazzo, G.C., Foletto, E.L., Jahn, S.L. & Villetti, M.A. 2012. Degradation of direct black 38 dye under visible light and sunlight irradiation by N-doped anatase TiO2 as photocatalyst. Journal of Environmental Management 98: 107-111.

Ding, Z., Lu, G.Q. & Greenfield, P.F. 2000. A kinetic study on photocatalytic oxidation of phenol in water by silica-dispersed titania nanoparticles. Journal of Colloid & Interface Science 232(1): 1-9.

Hasnat, M.A., Siddiquey, I.A. & Nuruddin, A. 2005. Comparative photocatalytic studies of degradation of a cationic and an anionic dye. Dyes & Pigments 66(3): 185-188.

He, H.Y. 2009. Comparison study of photocatalytic properties of SrTiO3 and TiO2 powders in decomposition of methyl orange. International Journal of Environmental Research 3(1): 57-60.

Hoffmann, M.R., Martin, S.T., Choi, W. & Bahnemann, D.W. 1995. Environmental applications of semiconductor photocatalysis. Chemical Reviews 95(1): 69-96.

Kannan, N. & Sundaram, M.M. 2001. Kinetics and mechanism of removal of methylene blue by adsorption on various carbons - a comparative study. Dyes & Pigments 51(1): 25-40.

Kim, S. & Choi, W. 2002. Kinetics and mechanisms of photocatalytic degradation of (CH3)nNH4-n+ (0 = n = 4) in TiO2 suspension: The role of OH radicals. Environmental Science & Technology 36(9): 2019-2025.

Lakshmi, S., Renganathan, R. & Fujita, S. 1995. Study on TiO2-mediated photocatalytic degradation of methylene blue. Journal of Photochemistry & Photobiology A: Chemistry 88(2-3): 163-167.

Lee, J., Choi, W. & Yoon, J. 2005. Photocatalytic degradation of N-nitrosodimethylamine: Mechanism, product distribution, and TiO2 surface modification. Environmental Science & Technology 39(17): 6800-6807.

Lee, J., Park, H. & Choi, W. 2002. Selective photocatalytic oxidation of NH3 to N2 on platinized TiO2 in Water. Environmental Science & Technology 36(24): 5462-5468.

Low, G.K.C., McEvoy, S.R. & Matthews, R.W. 1991. Formation of nitrate and ammonium ions in titanium dioxide mediated photocatalytic degradation of organic compounds containing nitrogen atoms. Environmental Science & Technology 25(3): 460-467.

Mangrulkar, P.A., Kamble, S.P., Joshi, M.M., Meshram, J.S., Labhsetwar, N.K. & Rayalu, S.S. 2012. Photocatalytic degradation of phenolics by N-doped mesoporous titania under solar radiation. International Journal of Photoenergy 2012: Article ID. 780562.

Mulvaney, P., Swayambunathan, V., Grieser, F. & Meisel, D. 1990. Effect of the potential on electron transfer to colloidal iron oxides. Langmuir 6(3): 555-559.

Ogata, Y., Tomizawa, K. & Adachi, K. 1981. Photo-oxidation of ammonia with aqueous hydrogen peroxide. Memoirs of the Faculty of Engineering, Nagoya University 33(1): 58-65.

Park, H. & Choi, W. 2005. Photocatalytic reactivities of Nafion-coated TiO2 for the degradation of charged organic compounds under UV or visible Light. The Journal of Physical Chemistry B 109(23): 11667-11674.

Sakthivel, S. & Kisch, H. 2003. Daylight photocatalysis by carbon-modified titanium dioxide. Angewandte Chemie International Edition 42(40): 4908-4911.

Sawyer, C.N., Mccarty, P.L. & Parkin, G.F. 2003. Chemistry for Environmental Engineering and Science. 5th ed. New York: McGraw-Hill.

Turchi, C.S. & Ollis, D.F. 1990. Photocatalytic degradation of organic water contaminants: Mechanisms involving hydroxyl radical attack. Journal of Catalysis 122(1): 178-192.

Vohra, M.S., Selimuzzaman, S.M. & Al-Suwaiyan, M.S. 2011. Aqueous phase thiosulfate removal using photocatalysis. International Journal of Environmental Research 5(1): 247-254.

Vohra, M.S., Selimuzzaman, S.M. & Al-Suwaiyan, M.S. 2010. NH4+-NH3 removal from simulated wastewater using UV-TiO2 photocatalysis: Effect of co-pollutants and pH. Environmental Technology 31(6): 641-654.

Vohra, M.S., Lee, J. & Choi, W. 2005. Enhanced photocatalytic degradation of tetramethylammonium on silica-loaded titania. Journal of Applied Electrochemistry 35(7-8): 757-763.

Vohra, M.S. & Tanaka, K. 2003. Photocatalytic degradation of aqueous pollutants using silica- modified TiO2. Water Research 37(16): 3992-3996.

Vohra, M.S. & Tanaka, K. 2001. Enhanced photocatalytic activity of Nafion-coated TiO2. Environmental Science & Technology 35(2): 411-415.

Wang, W.Y. & Ku, Y. 2007. Effect of solution pH on the adsorption and photocatalytic reaction behaviors of dyes using TiO2 and Nafion-coated TiO2. Colloids & Surfaces A: Physicochemical & Engineering Aspects 302(1-3): 261-268.

Wei, T.Y., Wang, Y.Y. & Wan, C.C. 1990. Photocatalytic oxidation of phenol in the presence of hydrogen peroxide and titanium dioxide powders. Journal of Photochemistry & Photobiology A: Chemistry 55(1): 115-126.

Zou, Z., Ye, J., Sayama, K. & Arakawa, H. 2001. Direct splitting of water under visible light irradiation with an oxide semiconductor photocatalyst. Nature 414(6864): 625-627.

Zhu, X., Castleberry, S.R., Nanny, M.A. & Butler, E.C. 2005. Effects of pH and catalyst concentration on photocatalytic oxidation of aqueous ammonia and nitrite in titanium dioxide suspensions. Environmental Science & Technology 39(10): 3784-3791.

Zhu, X., Nanny, M.A. & Butler, E.C. 2007.  Effect of inorganic anions on the titanium dioxide-based photocatalytic oxidation of aqueous ammonia and nitrite. Journal of Photochemistry & Photobiology A: Chemistry 185(2-3): 289-294.

 

 

*Corresponding author; email: vohra@kfupm.edu.sa

 

 

 

 

 

 

 

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