Utilization of Chicken Eggshells as Catalyst in Biodiesel Synthesis from Waste Cooking Oil

Solid oxides are the most used catalyst for the synthesis of biodiesel, one of which is calcium oxide (CaO). This research reports the synthesis of CaO catalysts sourced from chicken eggshells through the calcination process. Chicken eggshells were cleaned and dried for 24 h at 120 oC. The eggshells were then calcined at temperatures varying from 600 oC to 900 oC for 6 h and the resulted sample were characterized by FTIR and XRD. The biodiesel synthesis was conducted at 65 ºC with a reaction time of 2 h and the concentration of catalyst was varied at 3 wt%, 6 wt%, and 9 wt%. The optimal biodiesel synthesis was obtained at a concentration of CaO catalyst formed at a calcination temperature of 900 ºC at 9 wt%. The yield of biodiesel conversion was obtained at 81.43 % and glycerol was produced as a by-product.

Prediction of Global Corrosion and Corrosion Products Behavior in the Primary Circuit of LBE Fast Reactor

For better understanding the corrosion and corrosion products behavior in the primary circuit of lead-bismuth eutectic (LBE) coolant reactor, the concentration distribution of soluble impurities and the transport of solid particles are investigated through finite-element method. An axisymmetric model of the primary circuit of LBE reactor was constructed to accelerate the calculation the thermal hydraulic filed of circuit. The saturation concentration of solute Fe, Cr and Ni in LBE coolant are identified through the equilibrium of their oxides and PbO. And the very different saturation concentrations of Fe/Cr/Ni in LBE will lead to significant element selective corrosion. The migration of solid oxides particles in the primary circuit is also investigated by the Euler-Lagrange tracing model. The simulation shows that driving force for the movement of particles >100 μm is buoyancy, which lets particles float on a free surface, while particles <10 μm tend to suspend in coolant. However, the behavior of particles also depends on the formation position, the particles formed above the core have the high possibility of re-entering in the core.

Comparison of Support Effects on Phillips and Metallocene Catalysts

Both metallocene and Phillips chromium catalysts are used in the commercial manufacture of polyethylene. Unlike most other commercial metallocene systems, the Chevron Phillips Chemical (CPC) platform does not use methylaluminoxane or fluoroorganic boranes. Instead, the support itself serves to activate (ionize) the metallocenes, which then polymerize ethylene at high activity. Most of these solid acid supports can also be used to anchor Cr to make a Phillips catalyst. This provides an interesting opportunity to compare the polymerization responses by these two disparate systems, Phillips Cr and CPC metallocene, when supported on the same solid acid carriers. In this study, both chromium oxide and several metallocenes were deposited onto a variety of solid oxides, under a variety of conditions, and the resulting support effects were observed and compared. Although using seemingly different chemistries, the two catalyst systems exhibited a surprising number of similarities, which can be attributed to the acidity and porosity of these diverse supports.

Maintaining pronounced proton transportation of solid oxides prepared with a sintering additive

Proton-conducting electrolytes (PCEs) have led to significant advances in the fields of solid-state ionics, energy conversion and high-temperature electrochemistry, providing the basis of various solid oxide devices that demonstrate outstanding...

Electrolytic iron production from alkaline suspensions of solid oxides: compared cases of hematite, iron ore and iron-rich Bayer process residues

Iron can be produced by the direct electrochemical reduction of hematite particles suspended in hot, concentrated NaOH solutions. Because various other iron sources can be considered, the present work was aimed at investigating the electrolytic treatment of the “red mud” generated by the Bayer process for alumina preparation from bauxite. Such sources contain very high amounts of impurities, in particular silicon and aluminium oxide-based minerals, in addition to other mineral phases. Electrolytic reductive treatment of the industrial red mud sample was shown to be possible but with both lower current density and current efficiency than for pure hematite. After deposition tests at a fixed current density, further experiments in simulation tests have been carried out for better understanding. In particular, hematite particles were tested with and without impurities introduced in the solution. Presence of little soluble impurities at the particle surface appear to hinder the reactivity of the suspended particles at the cathode surface, whereas side-hydrogen reaction still occurs.