Chemical Engineering

STEFANO CERBELLI
MARIA ANNA MURMURA

The course builds on the basic concepts of Chemistry and Physycs and is aimed to provide
the students with the conceptual tools for modelling chemical and phase equilibria and chemical equilibrium problems.The students are expected to be able to analyse simple problems (low
pressure) by means of equilibrium conditions obtained fron the second
law of thermodynamics: in particular the students should be able to
reduce the equilibrium equations to the significant terms for a
specific situation,
by means of the order of magnitude analysis.

The objective of the course is to provide the knowledge required to study both chemical equilibria and phase equilibria for pure components and binary mixtures, under conditions of moderate deviation from ideality.

The course is based on knowledge acquired in Chemistry and Physics I

Material balances for non reacting systems
Total mass balance for multicomponent systems, Mass for each component, Stationary systems evaluation of degrees of freedom. Mass balance for simple non stationary systems.
Energy Balances
Internal energy and entalpy. First law of thermodynamics for closed systems. Constant volume or constant pressure heat capacity definitions. Standard heat formation definition. Heat reaction definition. Reference state and evaluation of internal energy or entalpy changes also for reacting systems. Energy balance for open systems: expansion of a fluid in a valve, compression power.
Second law of thermodynamics
Entropy definition. Evaluation of entropy changes for various tran sformations. Macroscopic entropy balance. Equilibrium condition for systems with different constraints. Fugacity and fugacity coefficient for a pure fluid: Poynting effect:
Equations of state
Two and tree parametrs corresponding state principle. Van der Waals and Redlich Kwuong cubic equations of state: equations: parameters evaluation. Vapor pressure evaluations by means of cubic equations of state. Virial equations Empirical equations for vapour pressure evaluation. Evaluation of thermodynamic properties with different EOS. State equations for mixtures: mixing rules definition.
Thermodinams of multicomponent systems
Fugacity and fugacity coefficient for a mixture and for a single component in the mixture. Lewis-Randall rule. Evaluation of fugacity coefficients by means of different EOS. Activity and activity coefficients. Raoult reference state. Definition of Henry constant and of Henry reference state. Variation of activity coefficients with temperature and pressure . Empirical models to represent the activity coefficients dependence on composition: Margules e Van Laar models. Evaluation of activity constants. Activity coefficients for ternary systems.
Equilibrium conditions for reacting or non reacting systems
Phase equilibrium in multicomponent systems. Chemical equilibrium criterion. Phase rule
Liquid-liquid equilibrium
Binary sistems: equilibrium conditions. Critical solution conditions. Symmetric systems. Changes of the composition of phases in equilibrium with temperature. Ternary liquid liquid equilibrium.
Vapor liquid equilibrium
Vapor liquid equilibrium condition: binary and multicomponents systems. Ideal systems: evaluation of boiling point and dew point at fixed pressure or temperature. Non ideal systems in liquid phase: evaluation of boiling point and dew point at fixed pressure or temperature. Azeotropic condition for omogeneous systems. Liquid-liquid vapour systems: evaluation of hetherogeneous azeotropy. LLV equilibria in systems showing complete immiscibility. Condensation curves.
Gas liquid equilibrium
General equilibrium condition. Solubility of a gas in a liquid: changes of solubility with pressure or temperature. Condensation of a vapor in the presence of a gas. Hunidity definition.
Chemical equilibrium
Definition and evaluation of the chemical equilibrium constant K, Variation of K with temperature. Omogeneous reacting systems: evaluation of equilibrium composition. Heterogeneous chemical reactions: evaluation of composition of different phases.

"Termodinamica per l’ingegneria chimica" di Fausto Gironi

In class lectures

Presence

Written exam: numerical problems
Oral exam: admission based on the results of the written exam, discussion of problems and questions on theoretical aspects

- Evaluation of equilibrium conditions for pure components and binary mixtures.
- Writing and solving mass and energy balance equations.
- Study of thermodynamic properties of pure components and mixtures.

• Thermodynamic properties
  • Books: "Termodinamica per l'Ingegneria Chimica I", F. Gironi


• Equations of state
  • Books: "Termodinamica per l'Ingegneria Chimica I", F. Gironi


• Fugacity and fugacity coefficients
  • Books: "Termodinamica per l'Ingegneria Chimica I", F. Gironi


• Activity and activity coefficients
  • Books: "Termodinamica per l'Ingegneria Chimica I", F. Gironi


• Model for evaluation of actiivty cofficients
  • Books: "Termodinamica per l'Ingegneria Chimica I", F. Gironi


• LL equilibria
  • Books: "Termodinamica per l'Ingegneria Chimica I", F. Gironi


• LV equilibria
  • Books: "Termodinamica per l'Ingegneria Chimica I", F. Gironi


• LG equilibria
  • Books: "Termodinamica per l'Ingegneria Chimica I", F. Gironi


• Chemical equilibria
  • Books: "Termodinamica per l'Ingegneria Chimica I", F. Gironi