**5. Conclusions**

This design project covers all four stages of experiential learning (experience, reflect, think, and act); the five differentiation principles; and both LOT and HOT from Bloom's taxonomy. Bare minimums have been built into the written report, where students must demonstrate their skill in the required calculations and explanations of observations. In DP5 where students explore the scale-up process, they have a choice in which unit operation to investigate. Depending on operational thinking level, students may choose an "easier" unit operation that requires less explanation than others, and will not be penalized. There is no upper limit to the depth in which students explore this project. The final requirement of the verbal presentation provides opportunities for students to learn oral communication skills, and importantly promotes independence as they explain their proj-

It is worth completing this discussion with a brief explanation of experiential activities that can be performed in a theory class. Remembering that experiential learning requires reflecting, thinking, and acting after an experience, a common activity employed by an educator is a thinking experiment. This requires the students to imagine a particular unit operation, and think about how it might work. Others might include practical demonstrations, real-life scenarios, or "story-telling" particularly in the form of analogies, which enables the learners

The author has previously introduced a very successful thinking experiment into ChE417: Separation Processes, at UM on fixed bed adsorbers. This is preceded by a theory lesson outlining the basic terminology of adsorption processes, typical adsorbents, and applications, followed by the various adsorption isotherms commonly discussed in the literature. This helps to build knowledge and creates an "experience" (although theoretical) of how adsorbers work and their typical applications. The thinking experiment begins in the following class, where the students are asked to think about how the concentration of solute in the fluid would vary as it travels over the length of a fixed bed adsorber. They draw their thoughts on a concentration vs. length graph. This is followed by a class discussion on mass transfer zones, and then students are asked to think about whether a narrow or wide mass transfer zone is better, with justification. They then need to discuss in groups what types of factors might affect the length and the rate of movement of this mass transfer zone, and are challenged to come up with at least 10 different factors. The thinking experiment continues where students are asked to draw on a concentration vs. time graph what the breakthrough situation may look like. With further discussion, they come to the realization that integrating such a curve will represent the amount of solute adsorbed for a given time. This exercise is highly engaging for the students, and enables them to fully "experience" the workings of a fixed bed adsorber, with considerable reflection and cognitive developmental opportunities. Acting on this new knowl-

edge is subsequently gained with calculation questions for fixed bed adsorber design.

ect in a realistic scenario.

**4. Non-experimental experiential activities**

16 Laboratory Unit Operations and Experimental Methods in Chemical Engineering

to access the complexities of a topic using more familiar situations.

A differentiation framework for higher education has been introduced and discussed, which extends the framework commonly used in K-12 education systems. This framework has been built on existing ideas of post-Piagetian thinking levels, and has mapped each thinking level to five broad differentiation principles. The framework has also been linked to Bloom's taxonomy of lower and higher order thinking skills.

Using this differentiation framework and experiential learning theories, a model for experimental classes in undergraduate chemical engineering unit operations has been developed. This model has been demonstrated using some pre-existing experimental activities described at ASEE 2016 [32, 34]. Its full capacity has been shown with a freshman chemical engineering design project currently operational at the University of Mississippi, providing examples of how all aspects of a differentiated activity can be developed, meeting the requirements of both thinking and learning skill development.
