Maximization of propylene in an industrial FCC unit

YesThe FCC riser cracks gas oil into useful fuels such as gasoline, diesel and some lighter products such as ethylene and propylene, which are major building blocks for the polyethylene and polypropylene production. The production objective of the riser is usually the maximization of gasoline and diesel, but it can also be to maximize propylene. The optimization and parameter estimation of a six-lumped catalytic cracking reaction of gas oil in FCC is carried out to maximize the yield of propylene using an optimisation framework developed in gPROMS software 5.0 by optimizing mass flow rates and temperatures of catalyst and gas oil. The optimal values of 290.8 kg/s mass flow rate of catalyst and 53.4 kg/s mass flow rate of gas oil were obtained as propylene yield is maximized to give 8.95 wt%. When compared with the base case simulation value of 4.59 wt% propylene yield, the maximized propylene yield is increased by 95%

Modeling solubilities of gases in the ionic liquid 1-ethyl-3-methylimidazolium tris(pentafluoroethyl)trifluorophosphate using the Peng-Robinson equation of state

In this paper, vapor–liquid equilibrium (VLE) data of binary mixtures containing gases such as carbon dioxide (CO2), methane, ethane, propane, or butane in the ionic liquid 1-ethyl-3-methylimidazolium tris(pentafluoroethyl)trifluorophosphate ([emim][FAP]) have been modeled using the Peng–Robinson equation of state (PR-EoS), combined with quadratic mixing rules. The calculations were performed at various temperatures. All calculations were performed with only one adjustable binary interaction parameter except in the system with CO2. In that case, two adjustable binary interaction parameters were used. The results showed a temperature dependence of the adjustable parameters. In all cases, the calculated results have been found to be in good agreement with the experimental data. A total absolute average deviation in the bubble-point pressures of less than 3% was established over a wide temperature range (293–363 K) and pressures up to 11 MPa

Effect of additives on the CO2 absorption in aqueous MDEA solutions

The use of antifoaming and corrosion inhibitor agents to prevent foaming and corrosion, respectively, is widely used in the carbon dioxide (CO2) absorption process using alkanolamines. However, the effect of these agents on the capacity of the alkanolamine solutions to absorb CO2 is unknown. We present a study on the phase equilibria and solubility of CO2 in mixtures of aqueous methyldiethanolamine (MDEA) solutions with and without these additives and show how the liquid phase properties and CO2 loading capacity is affected

High pressure phase equilibria of binary mixtures of light hydrocarbons in the ionic liquid 1-hexyl-3-methylimidazolium tetracyanoborate

Ionic liquids have been proposed as alternative solvents for several chemical processes, including organic reactions and separations. Their well-known negligible volatility makes them perfect candidates for gas separations as no solvent losses are expected. 1-Hexyl-3-methylimidazolium tetracyanoborate ([hmim][TCB]) is a low viscosity ionic liquid with high capacity for carbon dioxide (CO2) absorption. In order to study whether the selected ionic liquid [hmim][TCB] is an appealing solvent for CO2 absorption, it is equally important that other constituents in the gas mixture will have a low absorption in [hmim][TCB]. In case we are dealing with CO2 removal from natural gas, low absorption in the ionic liquid of the light hydrocarbons like methane (CH4), ethane (C2H6) and propane (C3H8) is a prerequisite. In this paper, the solubility of CH4, C2H6 and C3 has been determined at temperatures ranging from 280 K to 370 K and pressures up to 12 MPa using a synthetic method. The CO2/CH4 selectivity has been found to be very high and a liquid–liquid partial immiscibility has been found for ethane and propane in [hmim][TCB]. The phase behavior of the system has been discusse