One-Step conversion of high FFA Crude Karanja oil (Pongamia pinnata) to Bio-diesel Using Portland cement as excellent heterogeneous catalyst

Abstract

Heterogeneous catalyst was prepared from Portland cement. The prepared heterogeneous catalyst was tested for catalytic activity in the transesterification of non-edible, high free fatty acid feedstock, such as crude karanja oil (CKO), for biodiesel production, at methanol reflux temperature. Gas chromatographic (Gc) analysis technique was used to determine the fatty acid methyl ester yield. The preparation of heterogeneous catalyst from low-cost sources, and the use of non-edible feedstock, only at methanol reflux temperature, were all aimed at reducing the cost of biodiesel production. Insight into the catalytic activities of catalyst was obtained by characterizations for their textural properties, using Brunnear-Emmet-Teller (BET) analysis technique, surface scanning electron microscopy (SEM) and electron dispersive x-ray (EDX) for microstructure, surface morphology and chemical composition; x-ray diffraction (XRD) and Fourier-Transform Infra-Red (FTIR) spectroscopy for structural and functional groups analyses, respectively. Differential thermal and thermogavimetric (DTA/TGA) analyses were performed to determine the proper temperature ranges for the dehydration, decomposition, desorption and oxidation of sample via the TGA curves and their melting points and changes in crystal structures via the DTA curves, for effective determination of calcination temperature. The application of Portland Cement-derived heterogeneous catalyst in the transesterification reaction revealed excellent activity in the transesterification of crude karanja oil, with excellent fatty acid methyl ester yield of over 97.87 %. Operational conditions such as methanol/oil mole ratio (1:3 - 18), catalyst loading (3 - 9 % by wt) and reaction time (0.5 – 7 hours), were investigated to obtain the optimum reaction conditions for the feedstock, while the reaction temperature was kept constant at methanol reflux temperature, to minimise cost of production, in line with the objective of this investigation. Calcined heterogeneous catalysts gave over 80% fatty acid methyl ester yields than the raw counterpart, which were attributed to changes in crystal structures and phases of catalysts, observed in the characterization of catalysts, after calcination. Keywords: Portland cement, heterogeneous catalyst, Crude Karanja oil, transesterification reaction, Feedstock

Potential Heterogeneous Catalysts from Three Biogenic Residues toward Sustainable Biodiesel Production: Synthesis and Characterization

“…The crystalline phases of microcline, KAlSi 3 O 8 (JCPDS 00‐001‐0705) and anorthite, CaAl 2 (SiO 4 ) 2 , (JCPDS 00‐002‐0523) were also identified at $${2\theta }$$ of 3$${3.64^\circ{}}$$ , $${38.83^\circ{}}$$ , $${46.66^\circ{}}$$ and $${45.58^\circ{}}$$ respectively. Ekeoma et al [36] . has identified this compound in clay formulation catalyst for biodiesel production, which is one of the most commonly heterogeneous catalysts as reported by Etim et al.…”

“…Also, the crystalline phase of anorthite, CaAl 2 (SiO 4 ) 2 , (JCPDS reference code 00‐002‐0523), which is also one of the mineral forms of carbonate, was found at $${2\theta =49.12^\circ{}}$$ and $${49.12^\circ{}}$$ . Ekeoma et al [36] . also identified this mineral in clay formulation catalyst for biodiesel production.…”

“…Also, the crystalline phase of anorthite, CaAl 2 (SiO 4 ) 2 , (JCPDS reference code 00-002-0523), which is also one of the mineral forms of carbonate, was found at 2q ¼ 49:12 � and 49:12 � . Ekeoma et al [36] also identified this mineral in clay formulation catalyst for biodiesel production. Therefore, the formation of anorthite at this peak might be due to the precipitation of clay material during periwinkle shell formation.…”

“…At 2q ¼ 14:99 � , Quart (SiO 2 ) phase was also discovered. Akpenpuun et al [41] and Olubajo et al [23] [36] has identified this compound in clay formulation catalyst for biodiesel production, which is one of the most commonly heterogeneous catalysts as reported by Etim et al. [28] The formation of microcline (KAlSi 3 O 8 ) and anorthite (CaAl 2 (SiO 4 ) 2 ) may be due to the heat application at this temperature (600 °C).…”

Engineering the Band Gap of a g-C3N4 Catalyst by the Incorporation of Organic Acid for Efficient Biodiesel Production

“…Over the past few decades, there has been a notable surge in scientific studies focusing on the construction of heterogeneous catalysts with precise morphological and textural qualities. − Their catalytic activity, which is related to the number of active sites and their accessibility for reactant molecules, is mainly influenced by these structural characteristics . Solid nitrogen-doped carbon materials, including graphitic carbon nitride (g-C 3 N 4 ), carbon nanotubes, and fullerenes, have been effectively used as heterogeneous supports to immobilize catalytically active components, thereby facilitating the selective production of desired products .…”