Isolate new microalgal strain for biodiesel production and using FTIR spectroscopy for assessment of pollutant removal from Palm Oil Mill Effluent (POME)

Abstract

In tropical countries, the palm oil industry discharges a large amount of wastewater. The wastewater can serve as an economical nutrient source or substrate that can support the cultivation of microalgae. This study aimed to identify the local species of microalgae potentially existing in the industrial wastewater of palm oil mill effluent (POME). POME was selected as the key source of waste due to its higher potential in producing lipids from microalgae as biofuel substrate. A novel green microalgal strain was isolated from POME of Kahang- Johor west palm oil mill in Malaysia and was identified as Chlamydomonas sp. and subsequently named UTM 98 with Catalogue No. of KR349061. This study emphasised the effectiveness of POME as the main carbon source to maintain the growth of microalgae and simultaneously to increase the lipid content. In this study, Fourier Transform Infrared spectroscopy (FTIR) and Gas Chromatography (GC-FID) were used to identify andquantify lipids in the freshwater microalgae. Cultivation of microalgae were initially carried out in 250 mL Erlenmeyer flask containing 100 mL medium at ± 30 °C with continuous illumination (± 14 µmol-1 m-2 s-1) andup to 20 d of cultivations. Results demonstrated that on the chromatogram, the highest retention achieved is belong to palmitic acid (C16:0). Chlamydomonas incerta (C. incerta) species is found to contain shorter chain fatty acids, mainly 16 - 18 carbon length, which is ideal for biodiesel production. FTIR spectrum of POME treated biomass displayed the shifting of peak at 591 cm-1 and also removal of C-Cl stretching. The spectrum of POME effluent treated biomass revealed broad peak at 3,430 cm-1. The results of SEM micrographs showed that, after treating POME with C. incerta, the cells became slightly rough and corrugated textures and some particles were found on the surface of the cell wall. Using POME as a rich carbon and nutrient source is also a promising approach either as natural environment treatment or as high-lipid-content raw material for production of biofuel.