(132e) Teaching Chemical Product Design

More graduating chemical engineers work on product design than process design, so many faculty are expanding their teaching to include a discussion of products. Our efforts on this expansion have centered on the template of ?needs, ideas, selection, and manufacture,? suggested in our book Chemical Product Design. This sequence has usually worked well with industrial audiences but has been less successful with undergraduates, who have trouble with product manufacture. This paper discusses why and suggests ways to improve the undergraduate experience. The problems with the current sequence depends on the type of product chosen. Three types of product are common. The first type includes commodity chemicals, which are judged by price. In many cases, this implies a process design not that different from that usually developed. Some interesting projects involve scaling down current processes; one good example is a process to make NH₃ from CH₄ made on a family farm. Our students handle this type of design challenge well. A second type of product is high, value-added molecules, which are often judged on time to market. Because product volumes are small, manufacture is usually effected in batch, using generic equipment. Kinetics commonly are only qualitative, because the major issue is whether a reaction takes less time than one shift. Adsorption and crystallization are more important separations than distillation and absorption. Our students need more help on batch reactor design and on these alternative separations to be effective on this design challenge. The third type of product depends on microstructure to provide a particular function. Here, manufacture is not unlike that of high, value-added molecules, using batch equipment. However, product quality is frequently assessed by a combination of objective and subjective methods. Students need help regarding identification of product attributes, scaling of consumer reactions, and use of test panels. With this additional help, undergraduates can do good designs on all three types of chemical products.