The extended form of the Gibbs phase rule can be used to determine the degrees of freedom possessed by a system consisting of several species which partake in one or more chemical reactions. Discusses the use of the rule, considering the number of system components, stoichiometric/special constraints, and applications. (JN)

Studies in relation to the silver complexes of porphyrins, corroles and carbaporphyrins are presented especially with relation to silver in the oxidation states II and III. It is seen that the Ag(sub III) complex was electrochemically readily and reversibly reduced to the corresponding Ag(sub II) complex, thus indicating that the complex could be…

Students frequently confuse and incorrectly apply the several "deltas" that are used in chemical engineering. The deltas come in three different flavors: "out minus in", "big minus little" and "now versus then." The first applies to a change in a stream property as the stream flows through a process. For example, the "[delta]H" in an energy…

Solid-liquid and liquid-liquid mixing experiments have been developed to provide students with a practical experience on suspension and emulsification processes. The laboratory focuses on the characterization of the process efficiency, specifically the influence of the main operating parameters and the effect of the impeller type. (Contains 2…

Examples of conceptests and suggestions for preparing them for use in an undergraduate, chemical engineering thermodynamics course are presented. Conceptests, combined with hand-held transmitters (clickers), is an effective method to engage students in class. This method motivates students, improves their functional understanding of…

The Onsager reciprocal relations are essential to multicomponent transport theory. A discussion of the principles that should be used to derive flux laws for coupled diffusion is presented here. Fluctuation theory is employed to determine the reciprocal relation for transport coefficients that characterize coupled mass and heat transfer in binary…

Ask a graduating chemical engineering student the following question: What makes one reactor different from the next? The answers received will often be unsatisfactory and will vary widely in scope. Some may cite the difference between the basic design equations, others may point out a PFR is "longer," and still others may state that it…

The publicly available free computer program, "SimChemistry," was used as an active learning tool in the chemical engineering curriculum at the University College of Boras, Sweden. The activity involved students writing their own simulation programs on topics in the area of molecular structure and interactions. Evaluation of the learning…

A batch distillation apparatus has been designed and built for use in the undergraduate unit operations laboratory course. The column is fully automated and is accompanied by data acquisition and control software. A mixture of 1­-propanol and 2-­propanol is separated in the column, using either a constant distillate rate or constant composition…

The chemical engineering profession is in the midst of a significant evolution, perhaps a revolution. As the profession moves toward product development and design and away from petroleum and chemical process development and design, a new paradigm for chemical engineering education is evolving. Therefore, a new generation of capstone design…

Particle production and solids processing are essential components of the contemporary process industries. Crystalline solids represent a large and important segment of this manufacturing sector. Chemical engineers, especially in the United States, have historically abandoned this subject, leaving it to pharmacists, physical chemists, material…

Described is recent history related to polymer science and engineering. Developments from 1920 to the current time are discussed. (RH)

Addresses pros and cons of the current accreditation system in chemical engineering. Includes a review of the organizational structure of the accreditation process, accreditation criteria, and the author's opinions on the process. (JN)

Degrees of freedom analysis, the nature of Sorel's equations and sparsity patterns, equation-tearing strategies, simple and complex separation operations, and the complete tearing method are among the topic areas addressed in this discussion of equilibrium-stage operations, with and without computer applications. (JN)