Phil Andrews Research Group

Anthony R. Auxilio PhD student (Commenced: May 2004) Phone: +61 3 9905 5511 Fax: +61 3 9905 4597 Anthony.Auxilio@sci.monash.edu.au anthonyauxilio@mpsc.ph tonyaux@yahoo.com

Educational qualifications

• BSc in Chemistry (1993) – Xavier University, Cagayan de Oro City, Philippines
• MScT in Physical Sciences (2003) – Mindanao Polytechnic State College, Cagayan de Oro City, Philippines.

Research Areas

Title of the current project(1): Adsorption and Intercalation of Acid Blue 9 on Mg-Al Layered Double Hydroxides with Variation in the Metal Ratio.

Summary: Layered double hydroxides (LDHs) of the type [Mg1-XAlX(OH)2]X+(CO32-)X/2•mH2O with variable Mg/Al ratios have been prepared by co-precipitation of Mg2+ and Al3+ ions at constant pH. The effect on the adsorption ability of these compounds with Acid Blue 9 has been evaluated by UV-Visible spectrophotometry, powder X-ray diffraction analysis, N2 adsorption/desorption analysis, scanning electron microscopy, energy-dispersive X-ray analysis, X-ray photoelectron spectroscopy and atomic absorption spectroscopy. Optimum adsorption of Acid Blue 9 was achieved for LDHs with Mg/Al ratios of 3.2 – 4.4. LDHs with such compositions giving an equilibrium binding constant (Ka) of ca. 1.2 x 105 M-1 with a maximum monolayer coverage (Cm) of ca. 7.6 x 10-2 mmol.g-1. This observation was correlated to the surface area, pore size and volume, crystallite size, particle size, phase purity of the material, interlayer spacing and the surface morphology of the LDHs. Powder XRD analysis after adsorption of 1.85 mM Acid Blue 9 in 20% (v/v) glycerol-H2O solvent system indicated that the dye was not intercalated between the brucite-like layers as no change was evident in the d(003) spacing. This indicated that the adsorption of the dye at this concentration was most likely due to outer surface binding. However, powder XRD analysis revealed that intercalation was achieved at 76 mM dye concentration in the same solvent system at Mg:Al ratios between 3.2 to 5.6. This results to the expansion of the interlayer spacing from ca. 8 Å to 19 Å to accommodate the Acid Blue 9 anion.

Title of the current project(2): Surface Modification of Aluminium Monohydroxides (AlOOH)

Summary: The synthesis of organic-inorganic materials is achieved through the coupling of both organic and inorganic moieties to offer a material with certain properties. This project will focus on producing particles with an overall cationic surface. This is achieved by reacting aluminium monohydroxides with L-lysine. The static and dynamical properties of L-lysine adsorbed onto the AlOOH were modelled by using semi-empirical quantum mechanics and force field techniques.

Project carried out previously: Antioxidant Activity Screening of Some Philippine Edible Leaves

Summary: This study investigated the antioxidant activities of selected local edible plant leaves using the modified thiocyanate method. The findings of the study showed that all extracts from the selected edible plant leaves have antioxidative activities with the following average Protective Values (PVs): Pisonia alba Span. (lettuce tree), 5.594; Capsicum anuum Linn. (green-hot pepper), 3.065; Ipomoea aquatica (kangkong), 2.344; Cucurbita maxima Duch (squash), 2.162; Momordica charantia L. (ampalaya), 1.988; Ipomoea batatas Linn. (camote), 1.892; Moringa oleifera Lam. (malunggay), 1.800; Basella rubra Linn. (alugbati), 1.690. These values are significantly higher compared to a PV of 1.000 which is considered devoid of antioxidative potential. According to the conditions utilized in the study and disregarding any interaction, only the solvent type and kind of plant showed significant effect on the PVs; leaf freshness was not signficant.

Conferences Attended

• 17th Philippine Chemistry Congress (May 23-25, 2001), Xavier Sports and Country Club, Cagayan de Oro City, Philippines
• CRC Smartprint Conference (July 6-7, 2004), Monash University, Australia
• CRC Smartprint Conference (October 19, 2005), Hilton Hotel, Melbourne, Australia.
• 20th Philippine Chemistry Congress held on April 11-13, 2005 at the Baguio Country Club, Baguio City, Philippines; Oral presentation: Adsorption and Intercalation of Acid Blue 9 on Mg-Al Layered Double Hydroxides with Variation in the Metal Ratio.

Publication

• Auxilio, A.R. Philippine Association for Graduate Education - Region 10, 2003, 3, 78.

Work Experience

• Xavier University (1994 – 1997) General Chemistry, Chemical Thermodynamics
• Mindanao Polytechnic State College (1998 – 2003) General Chemistry, Chemical Thermodynamics, Materials Science, Basic Inorganic Chemistry

Teaching commitments

• CHM 1042 – World of Chemistry - Practicals
• CHM 2911 – Molecular Design and Reactivity - Practicals
• CHM 3960 – Environmental Chemistry -Practicals
• CHM 3911 – Spectroscopy, synchrotron and structure - Practicals
• Experience Monash
• Victorian Certificate of Education (VCE) Workshop.

Hobbies & Interests

Practice playing tennis and drinking red wines and beers.