Biodiesel Production from Waste Cooking Oil Catalyzed by a Bifunctional Catalyst

Abstract

The objective of this study was to prepare bifunctional catalysts based on iron and CaO and test them in the biodiesel production using waste cooking oil (WCO) as feedstock. Two iron precursors were studied, Fe2O3 and Fe­(NO3)3·9H2O. The identified crystalline phases were Ca2Fe2O5 and CaFeO3. Surface morphology and textural properties (distribution of active species, specific surface area, size, and pore volume) were also analyzed. Additionally, thermal stability was studied and 800 °C was established as the optimum calcination temperature. The density of both acidic and basic sites was higher with the catalyst prepared with Fe2O3 than with that prepared with Fe­(NO3)3·9H2O. The latter, however, leads to reach equilibrium in half of the time than with the former. This was ascribed to the ratio of acidic to basic sites, which is higher with the catalyst prepared with the precursor salt. This ratio not only affects the overall cost of the process by affecting the time at which equilibrium is reached but also by dictating the methanol/oil molar ratio at which the equilibrium is reached sooner. The prepared bifunctional catalyst allowed us to produce biodiesel with 90% of methyl ester content at atmospheric pressure, reaction temperature of 60 °C, reaction time of 2 h, with 12:1 M ratio of methanol/WCO, 10 wt % of Fe over CaO, and a catalyst loading of 5 wt %. This catalyst can be used at least 3 times. The so-obtained biodiesel met the European norm EN-14214 regarding viscosity and density.

Thermally modified nanocrystalline snail shell adsorbent for methylene blue sequestration: equilibrium, kinetic, thermodynamic, artificial intelligence, and DFT studies

“…This shows that the adsorbent is crystalline in nature. The nding of this study is in agreement with previous studies, 53,55 thereby corroborating the results obtained in the SEM-EDX and FTIR analysis.…”

Current advances and future outlook of heterogeneous catalytic transesterification towards biodiesel production from waste cooking oil

“…308 Metals and their oxides can be mixed to provide bifunctional catalysts that can perform the acid-catalyzed esterification of FFA and base-catalyzed transesterification of triglycerides in a single step, reducing the reaction time and cost on a commercial scale. 309 The majority of current research focuses on enhancing stability or regeneration methods such as solvent washing or recalcination. Lee et al have reported the catalytic activity of various mixed metal oxides, like CaO–MgO, CaO–ZnO, CaO–La 2 O 3 , and MgO–ZnO, with Jatropha oil, and found that their activity as compared to their oxides enhanced in the order CaO–ZnO > CaO ∼ CaO–MgO ∼ CaO–La 2 O 3 > MgO–ZnO > MgO > ZnO > La 2 O 3 .…”

Biodiesel from Avocado Seed Oil with CaO and CaO Super Basa Catalyst from Egg Shell Waste

“…Reaksi trans-esterifikasi memerlukan katalis untuk mendapatkan rendemen biodiesel yang lebih banyak dan lebih berkualitas. Katalis basa heterogen lebih baik digunakan dalam proses reaksi trans-esterifikasi biodiesel dibandingkan dengan katalis basa homogen, karena dapat menghasilkan rendemen proses trans-esterifikasi lebih tinggi (Elliyanti et al, 2017) dan (Enguilo Gonzaga et al, 2021). Pada penelitian ini digunakan katalis basa heterogen yaitu katalis CaO dari limbah cangkang telur ayam broiler.…”

“…Penelitian (Oko & Feri, 2019) menghasilkan rendemen 96,073% dari minyak jarak. Hal tersebut dapat terjadi karena proses reaksi transesterifikasi dipengaruhi oleh beberapa faktor, yaitu kandungan asam lemak bebas dan kelembaban minyak, katalis, perbandingan molar alkohol dengan minyak, suhu reaksi dan waktu reaksi (Enguilo Gonzaga et al, 2021;Erchamo et al, 2021).…”