Graphic web–apps for teaching ternary diagrams and liquid–liquid extraction

Recent years have seen a rapid development in e-learning technologies. Specific topics; however, may require additional teaching tools created particularly for their unique characteristics. It is important that these tools are developed with learning outcomes in mind, and if possible are in a format easily accessible. We have developed graphic web applications for the teaching of liquid–liquid equilibria, single– and multi–stage liquid–liquid extraction using ternary phase diagrams. These applications allow students to draw liquid–liquid 2-phase equilibrium curves, calculate phase separation for a given mixture and graphically determine equilibrium stages; the correct results are then produced with hints for the students if they get stuck. Student usage figures and opinions have been collected for the application during trial use on a combined full-time taught and distance learning course in Engineering Separations at The University of Manchester. The current students have found these applications useful for developing their understanding of liquid–liquid equilibria.