Electro-oxidation of waste glycerol to tartronic acid over Pt/CNT nanocatalyst: study of effect of reaction time on product distribution

ABSTRACT

In this work, glycerol valorization into tartronic acid – one of the most valuable derivatives of glycerol – was reported over platinum supported on multi-walled carbon nanotubes (Pt/CNT) electrocatalyst. The nanocatalyst was synthesized using a chemical reduction method with hydrazine as a reducing agent. The physical analyses of catalyst were performed by BET, XRD, FESEM, EDX, and TEM. The XRD spectroscopy indicated a face-centered cubic crystalline structure with an average crystallite size of 4.2 nm. The field emission scanning electron microscopy analysis revealed that the particles were uniformly distributed over multi-walled carbon nanotubes, while EDX showed the elemental composition of Pt (17.52%) and C (82.48%). Electrochemical activity and stability of the catalyst were measured using cyclic voltammetry and chronoamperometry techniques. Electrochemical surface area (ECSA, 226.52 m²/g) and mass activity (MA, 5.74 mA/mg) were calculated in 0.5 M H₂SO₄ and 0.5 M glycerol/0.5 M KOH solution, respectively. The catalytic activity of Pt/CNT nanoparticles was analyzed from glycerol oxidation reaction (GOR), while the products distribution and selectivity were measured using high-performance liquid chromatography (HPLC). It was found that the tartronic acid was produced as a major product with a selectivity of 95.3% while small quantities (<1%) of mesoxalic acid, dihydroxyacetone, and glyceric acid were also produced. The higher activity and selectivity of Pt/CNT can be attributed to high electrochemical surface area and uniform distribution over support.

KEYWORDS:

• Electrochemical surface area
• glycerol oxidation reaction
• HPLC
• Pt/CNT
• tartronic acid

Acknowledgments

The authors would like to thank Universiti Malaysia Pahang for providing financial support from the grant PGRS 180335.

Additional information

Funding

This work was supported by the Universiti Malaysia Pahang [PGRS 180335].

Notes on contributors

Muhammad Sheraz Ahmad

Muhammad Sheraz Ahmad is a PhD scholar in the Faculty of Chemical and Natural Resources Engineering at Universiti Malaysia Pahang since October, 2016. His previous professional experience was with Education department (at Doha, Qatar), Attock Refinery Limited (ARL), Leads group of Pharmaceuticals and Atomic energy commission of Pakistan. His research interests encompass the field of catalysis mainly focusing on developing catalysts for biomass conversion to biofuel (by using electro-oxidation) and synthesis of medicinal important organic compounds. His research has published in quality indexed journals.

Chin Kui Cheng

Chin Kui Cheng is an Associate Professor in the Faculty of Chemical and Natural Resources Engineering at Universiti Malaysia Pahang. He joined the Faculty in August 2004. His research interests encompass the fields of Bioenergy, Reaction Engineering, Fuel Cell, Photocatalysis, Wastewater treatment. His research work focusing on developing catalysts for CO₂ conversion to fuel (by photocatalysis and photo-electrocatalysis), biodiesel production from Palm oil, wastewater treatment and power generation, dry reforming of hydrocarbons, and composite preparations. He is also an active reviewer for many high-impact journals published by ACS, Elsevier and Springer. His research profiler index is h-index 27 with more than 2000 citations.

Huei Ruey Ong

Huei Ruey Ong is working as a Senior Lecturer in DRB-HICOM University of Automotive Malaysia since Oct 2017. Concurrently, he also holds as Deputy Head (Consultancy) under Research Training and Consultancy (RTC). Prior to that, he was working as a postdoctoral fellow in University Malaysia Pahang (UMP). He is also a Professional Technologist (PTech) specialized in Chemical Technology field, awarded by Malaysia Board of Technologies (MBOT). His research interests encompass the fields of chemical reaction engineering, plastic and polymer synthesis, bio-/nano-composite making, energy and environment, nanofluids mainly focusing on the development of novel catalysts or material for different process or application. To date, his research profile is h-index 11 with 314 citations.

Hamidah Abdullah

Hamidah Abdullah is a Senior Lecturer in the Faculty of Chemical & Process Engineering Technology at Universiti Malaysia Pahang (UMP). She joined the UMP as a lecturer starting 2008. She graduated with a Bachelor Degree in Chemical Engineering and Master of Science from Unversiti Sains Malaysia. In 2018, she graduated in Doctor of Philosophy in Chemical & Process Engineering from Universiti Kebangsaan Malaysia. Her research interest is mainly focusing on developing catalysts for chemical reaction especially in photocatalytic reduction of CO₂ to hydrocarbon. She has published around 15 journal papers which have been cited for 153 times with h-index of 5.

Chi Shein Hong

Chi Shein Hong is an entrepreneur, actively involved in manufacturing industry and consultancy services. She received a bachelor degree in chemical engineering from Universiti Teknologi Malaysia in 2009 and master’s degree in chemical engineering from Universiti Malaysia Pahang, She also involved as co-author for a few research papers and reviewer for journal as well. In addition, she also worked as research officer and assistant for several industry and research projects. She obtained her professional technologist qualification from MBOT in 2018, associate member from IChemE in 2017 and graduate engineer from BEM in year 2016, after working for years in industry especially in manufacturing line.

Gek Kee Chua

Gek Kee Chua is currently an Associate Professor in the Faculty of Chemical and Process Engineering Technology, Universiti Malaysia Pahang. She received her PhD degree from Massey University, New Zealand in Bioprocess Engineering. She has co-authored more than 20 publications including Biotechnology Progress, Process Biochemistry, Chemical Engineering Research and Design, Chemical Engineering Communications. Dr Chua’s current research focus on enzymatic reaction and application of fermentation technology in waste valorization.

Puranjan Mishra

Puranjan Mishra studied Biotechnology at Himachal Pradesh University, India. He received his PhD degree from University Malaysia Pahang in 2018. Presently he is carrying out his Post-doctoral at University Malaysia Pahang, Malaysia. His current research interest is in the area of Enzymology, Nanomaterials synthesis, and Waste water treatment, mainly for Energetic applications (H₂ and CH₄, Biomass utilization). His scientific research work has been published in more than 25 quality indexed journals and has been cited more than 100 times with h-index 5.

Md. Maksudur Rahman Khan

Md. Maksudur Rahman Khan is a Professor in the Faculty of Chemical and Natural Resources Engineering at Universiti Malaysia Pahang. He joined the Faculty in August 2010. His previous professional experience was with Department of Chemical Engineering and Polymer Science at Shahjalal University of Science and Technology and Fuel Cell Centre, Yuan Ze University. His research interests encompass the fields of energy and environment mainly focusing on developing catalysts for CO₂ conversion to fuel (by photocatalysis and photo-electrocatalysis), biodiesel production from nonedible oils, simultaneous wastewater treatment and power generation by microbial fuel cells, dry reforming of hydrocarbons as well as biopolymer and composite preparations. He has published more than 150 journal papers which have been cited more than 2000 times with an h-index of 24. He is also an active reviewer for many high-impact journals published by ACS, Elsevier and Springer.