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.