Synthesis of diethyl carbonate from ethanol and CO 2 over ZrO 2 catalysts
- PDF / 1,504,232 Bytes
- 11 Pages / 595.276 x 790.866 pts Page_size
- 15 Downloads / 184 Views
ORIGINAL PAPER
Synthesis of diethyl carbonate from ethanol and CO2 over ZrO2 catalysts Felipe Girondi Denardin1 · Gustavo Paim Valença1 Received: 2 March 2020 / Revised: 6 October 2020 / Accepted: 10 October 2020 © Associação Brasileira de Engenharia Química 2020
Abstract Diethyl carbonate (DEC) is a versatile chemical with several commercial uses. The synthesis of DEC from carbon dioxide and ethanol is both environmentally friendly and can be integrated into the ethanol biorefinery. A thermodynamic evaluation was made to predict the amount of DEC produced at equilibrium at the reaction conditions used in this work. Zirconium oxide solids were prepared using sol–gel methodology and were loaded with Na, Mg or PO4−3 using the incipient wetness impregnation method. Catalytic tests were carried out in a 500 mL stainless steel Parr reactor at 423 K. The DEC yield decreased as the Na or Mg load increased, while increasing the yield of acetaldehyde. However, DEC yield and selectivity increased as the PO4−3 load increased, while the acetaldehyde yield decreased. Lower overall acid site density and lower than 2.8 µmol-CO2/m2 basic site density resulted in a higher DEC yield. Keywords Ethanol · CO2 · Diethyl carbonate · Zirconia List of symbols Cp Specific heat (kJ mol−1 K−1) ∆rCp Specific heat of the reaction (kJ mol−1 K−1) DBJH BJH desorption diameter (nm) ∆Gof,i Gibbs free energy of formation (kJ mol−1) ∆rGo298 Reaction Gibbs free energy at 298 K (kJ mol−1) ∆rGoT Reaction Gibbs free energy at temperature T (kJ mol−1) o ∆H f,i Standard formation enthalpy (kJ mol−1) ∆rHo298 Reaction enthalpy at 298 K (kJ mol−1) ∆rHoT Reaction enthalpy at temperature T (kJ mol−1) vi Stoichiometric coefficients Keq Reaction equilibrium constant (cm3 mol−1) pv Pore volume (cm3 g−1) R Universal gas constant (kJ mol−1 K−1) [EtOH]0 Ethanol concentration in the liquid phase (mol L−1) SBET B.E.T. surface area (m2 g−1) Vl liquid Molar volume (cm3) Vg gas Molar volume (cm3) Vt Total pore volume (cm3) * Gustavo Paim Valença [email protected] 1
Faculdade de Engenharia Química, Universidade Estadual de Campinas, Av. Albert Einstein 500, Campinas, SP 13083‑852, Brazil
Greek letters λ X-ray wavelength (nm) 2θ Incidence peak angle in XRD (o)
Introduction Diethyl carbonate, also called ethyl carbonate or diethyl ester, is a colorless transparent liquid under normal conditions. Diethyl carbonate has some unique applications; it is used in lubricants, cosmetics, as plasticizers, in pharmaceutical applications and as electrolyte in lithium-ion batteries (Prymak et al. 2015). Diethyl carbonate is being increasingly used as a carbonylation and ethylation agent in the place of hazardous, waste-generating compounds (Huang et al. 2013). In addition, DEC has a higher oxygen content compared to methyl tert-butyl ether (MTBE) and has been proposed as a replacement for MTBE as an oxygen-containing fuel additive (Ma et al. 2003). Diethyl carbonate is biodegradable and it decomposes to C O2 and ethanol, which is another adv
Data Loading...
