Sains Malaysiana 47(6)(2018): 1085–1091


Oxidation of p-Cresol by Ozonation

(Pengoksidaan p-Cresol oleh Pengozonan)




School of Environmental Engineering, Universiti Malaysia Perlis (UniMAP), Kompleks Pusat Pengajian Jejawi 3, 02600 Arau, Perlis Indera Kayangan, Malaysia


Diserahkan: 22 Disember 2017/Diterima: 7 Februari 2018



Oxidation of p-Cresol was investigated by using ozonation process. The aim of this research is to assess the effectiveness of ozonation on oxidation of micropollutant such as p-Cresol. Ozonation performance was evaluated based on p-Cresol concentration reduction and chemical oxidation demand (COD) reduction. It was found ozonation at pH11 achieved the highest p-Cresol degradation, with 95.8% of p-Cresol reduced and 96.0% of COD reduced, for an initial 50 mgL-1 of p-Cresol. The degradation of p-Cresol could be expressed by second-order of kinetic model. The second-order rate constant k increases as the initial pH increased, but decreases with the increasing of initial p-Cresol concentrations. Besides, the absorption spectra of p-Cresol over ozonation time were analyzed by spectrophotometry. The evolution of absorption spectra of p-Cresol degradation suggests that the oxidation of p-Cresol follows three stages mechanisms with cycloaddition as the first step to produce aromatic intermediates followed by ring-opening reactions, degradation of the intermediates, and subsequently achieved mineralization.


Keywords: Absorption spectra; mechanism; micropollutant; ozonation; p-Cresol



Pengoksidaan p-Cresol dikaji dengan menggunakan proses pengozonan. Tujuan penyelidikan ini adalah untuk menilai keberkesanan pengozonan terhadap pengoksidaan pencemar mikro seperti p-Cresol. Prestasi pengozonan dinilai berdasarkan pengurangan kepekatan p-Cresol dan pengurangan permintaan oksigen kimia (COD). Didapati pengozonan pada pH11 mencapai kemerosotan p-Cresol tertinggi, dengan 95.8% p-Cresol dikurangkan dan 96.0% COD dikurangkan, untuk awalan 50 mgL-1 p-Cresol pada suhu bilik. Degradasi p-Cresol boleh dinyatakan oleh model kedua kinetik. Pesanan laju pesanan kedua k meningkat apabila pH awal meningkat, tetapi berkurangan dengan peningkatan kepekatan p-Cresol awal. Selain itu, spektrum penyerapan p-Cresol ke atas masa pengozonan dianalisis spektrofotometri. Evolusi spektrum penyerapan degradasi p-Cresol menunjukkan bahawa pengoksidaan p-Cresol mengikuti tiga peringkat mekanisme dengan pensiklotambahan sebagai langkah pertama untuk menghasilkan perantara aromatik diikuti oleh reaksi pembukaan cincin, kemerosotan perantaraan dan seterusnya pemineralan.


Kata kunci: Mekanisme; pencemar mikro; pengozonan; p-Cresol; spektrum penyerapan


Abdollahi, Y., Abdullah, A.H., Zainal, Z. & Yusof, N.A. 2012. Photocatalytic degradation of p-cresol by zinc oxide under UV irradiation. International Journal of Molecular Sciences 13(1): 302-315.

Agency for Toxic Substances and Disease Registry (ATSDR). 2008. Toxicological Profile for Cresols. Atlanta, GA: U.S. Department of Health and Human Services, Public Health Service.

Atkinson, R. 1986. Kinetics and mechanisms of the gas-phase reactions of the hydroxyl radical with organic compounds under atmospheric conditions. Chemical Reviews 86(1): 69-201.

Bello, I.A., Oladipo, M.A., Giwa, A.A. & Adeoye, D.O. 2013. Adsorptive removal of phenolics from wastewater: A review. International Journal of Basic and Applied Science 2(1): 79-90.

Buxton, G.V., Greenstock, C.L., Helman, W.P. & Ross, A.B. 1988. Critical review of data constants for reactions of hydrated electrons, hydrogen atoms and hydroxyl radicals (.OH/.O-) in aqueous solution. Journal of Physical and Chemical Reference Data 17(2): 513-886.

Centers for Disease Control and Prevention (CDC). 2007. Centers for Disease Control and Prevention. niosh/ipcsneng/nengicsc.html. Accessed on 11 November 2014.

Das, L., Kolar, P., Classen, J.J. & Osborne, J.A. 2013. Adsorbents from pine wood via K2CO3-assisted low temperature carbonization for adsorption of p-Cresol. Industrial Crops & Products 45: 215-222.

Escudero, C.J., Iglesias, O., Dominguez, S., Rivero, M.J. & Ortiz, I. 2017. Performance of electrochemical oxidation and photocatalysis in terms of kinetics and energy consumption.

New insights into the p-cresol degradation. Journal of Environmental Management 195: 117–124.

Hoigne, J. & Bader, H. 1976. The role of hydroxyl radical reactions in ozonation processes in aqueous solutions. Water Research 10(5): 377-386.

Hoigne, J. & Bader, H. 1983. Rate constants of reaction of ozone with organic and inorganic compounds in water - II: Dissociating organic compounds. Water Research 17(2): 185-194.

Hsu, Y.C., Yang, H.C. & Chen, J.H. 2005. The effects of preozonation on the biodegradability of mixed phenolic solution using a new gas-inducing reactor. Chemosphere 59: 1279-1287.

Kavitha, V. & Palanivelu, K. 2005. Destruction of cresols by Fenton oxidation process. Water Research 39(13): 3062-3072.

Kurniawan, T., Lo, W. & Chan, G. 2006. Radicals-catalyzed oxidation reactions for degradation of recalcitrant compounds from landfill leachate. Chemical Engineering Journal 125: 35-57.

Lewis, R.J. 2001. Cresols. Hawley’s Condensed Chemical Dictionary 14: 306-307. New York: John Wiley and Sons.

O’Neil, M.J., Smith, A. & Heckelman, P.E. 2001. Cresols. An Encyclopedia of Chemicals, Drugs, and Biologicals. Whitehouse Station, NJ: Merck & Co.

Olariu, R.I., Klotz, B., Barnes, I., Becker, K.H. & Mocanu, R. 2002. FT-IR study of the ring-retaining products from the reaction of OH radicals with phenol , o - , m - , and p -cresol. Atmospheric Environment 36(22): 3685-3697.

Rattabal, K. & Grisdanurak, N. 2016. Mechanism pathway and kinetics of p-cresol photocatalytic degradation over titania nanorods under UV-visible irradiation. Chemical Engineering Journal 296: 420-427.

Singh, R.K., Kumar, S., Kumar, S. & Kumar, A. 2008. Development of parthenium based activated carbon and its utilization for adsorptive removal of p-cresol from aqueous solution. Journal of Hazardous Materials 155(3): 523-535.

Sun, Y., Ren, X. & Cui, Z. 2012. The degradation mechanism of phenol induced by ozone in wastes system. Journal of Molecular Modeling 18(8): 3821-3830.

Surkatti, R. & El-Naas, M.H. 2014. Biological treatment of wastewater contaminated with p-cresol using Pseudomonas putida immobilized in polyvinyl alcohol (PVA) gel. Journal of Water Process Engineering 1: 84-90.

Tehrani-Bagha, A.R., Mahmoodi, N.M. & Menger, F.M. 2010. Degradation of a persistent organic dye from colored textile wastewater by ozonation. Desalination 260(1-3): 34-38.

Turhan, K. & Uzman, S. 2008. Removal of phenol from water using ozone. Desalination 229 (1–3): 257-263.

Valsania, M.C., Fasano, F., Richardson, S.D. & Vincenti, M. 2012. Investigation of the degradation of cresols in the treatments with ozone. Water Research 46(8): 2795-2804.

Wang, Y., Yang, W., Yin, X. & Liu, Y. 2016. The role of Mn-doping for catalytic ozonation of phenol using Mn/_-Al2O3 nanocatalyst: Performance and mechanism. Journal of Environmental Chemical Engineering 4(3): 3415-3425.

Wojnárovits, L., Földiák, G., D’Angelantonio, M. & Emmi, S.S. 2002. Mechanism of OH radical-induced oxidation of p- cresol to p- methylphenoxyl radical. Research on Chemical Intermediates 28(4): 373-386.

Wu, P., Li, J., Li, S. & Tao, F.M. 2012. Theoretical study of mechanism and kinetics for the addition of hydroxyl radical to phenol. Science China Chemistry 55(2): 270-276.



*Pengarang untuk surat-menyurat; email: