EXPERIMENTS

1. Methanation in a fixed bed catalytic reactor CatReact TA: Torren Carlson This experiment studies the nickel catalyzed methanation from CO and H2. The catalyst can easily deactivate due to the formation of coke on the Ni. This occurs when CO is added in excess of stoichiometric. H2 at ca. 300C for several hours activates the catalyst and reverses coke formation. This semester we have two reactors in place, a CSTR and a PFR. The general kinetics (L-H kinetics), including activation energies for the rate controlling step, the regions for diffusion control, and catalyst deactivation (and regeneration) can be studied. We have a new surface analyzer (a single point BET system) in the lab by which you can measure the surface areas for the catalyst and thus to estimate a TOF, turn over frequency. There are several kinetic simulation packages for catalytic reactions that may be employed to represent the catalytic reactors. 2. Polymerization kinetics PolyKin TA: Vikram Daga Methyl-Methacrylate is polymerized with AIBN as the initiator in this batch polymerization in a dilatometer. The polymerization can be run in several ways: bulk, or in toluene, butanol, methanol, benzene and/or cyclohexane. In all cases, you are to focus on the differences between the results you find and those of prior studies in our labs or in the literature. In the case of literature results, you will most probably confirm their findings. Differences in the kinetics should be studied; specifically, the activation energies will differ for certain optional changes. In other cases, the differences will be most reflected in the nature of the polymer product that is produced. For polymer products, the first measure is the molecular weight distribution, which will be measured with GPC in the PSE department (you will need to understand the technique). We will work a protocol whereby this characterization data can be obtained for a limited number of samples (e.g., < 6 in two sets of four). You should be familiar with those kinetic and mechanistic components that control the molecular weight distribution. These experiments are typical in the development of a new polymer product(s) wherein the range of reaction variables are studied to optimize a polymer for specific applications based on the polymer properties, MWD being the first. 3. Binary Distillation Distill TA: Sumeet Pandey The purpose of this experiment is to introduce you to elementary aspects of the most widespread separation technique in the chemical industry – distillation. The assignments allow the important concepts of reflux and reboil to be demonstrated, and to examine how these variables influence the purity of the distillate and bottoms streams. Because the column is fitted with view ports on many trays, hydrodynamic effects such as flooding and weeping can also be observed. The primary control variables are the steam into the reboiler and the reflux flow. The dependant variables are the bottom and product compositions, respectively. Several variables dictate the dynamics and eventual control of product compositions. It is crucial that you present a proper energy analysis of this system. There are several options in the analysis of energy, depending on where you draw the boundaries. All involve measuring the rate of steam condensing in the reboiler. We will have a sight glass to monitor the level of liquid at the exit of the reboiler and you will need to work out a protocol to quantify the energy transferred from the steam. 4. BioDiesel BioDiesel TA: Torren Carlson The production of BioDiesel is one of the fastest growing processes to produce liquid fuels from renewable resources. Vegetable oils, fats and algae extracts are converted to Diesel fuels for use in home heating, Diesel engines and turbines (including jets and generators). The basic reaction is a trans-esterification process that converts the triglycerides of oil to FAMEs (look it up) by the base catalyzed reaction with methanol (or ethanol). However, current processes and plants are far from optimum. You will study the kinetics of these reaction and associated separation processes with the goal of understanding the opportunities for process improvement in BioDiesel plants from raw or waste vegetable oil. 5. Characterization/Control of a heat exchanger HeatEx TA: Sumeet Pandey The focus for this semester is heat exchange. One is first to estimate the various heat transfer coefficients for the system at the several interfaces in this system (inner and outer) and the changes that occur as a function of the various flows (water and steam). You should complete an energy balance on the system for different configurations. These options involve control of any of several temperatures (of the process or cooling water at various points) employing any of several variables (steam, cooling and process water). The process can be operated in co- or counter-current flow modes for the water-water heat exchanger. What are the differences? 6. Membrane separation by permeation Perm TA: Soumitra Choudhary 'Sam' The permeation experiments studies the enrichment of oxygen from binary and tertiary gas mixtures flowing in series or/in parallel into two permeation bundles. You can investigated separation of O2 from N2, Ar and He. You will have mixtures of O2 in He, N2 and Ar and O2 in CO2 as well as ternary mixtures of N2/O2/CO2 and N2/Ar/CO2, often with different mole fractions. You will propose to compare the enrichment of oxygen as a function of flow-rate/back-pressure from different feeds and to compare these to prior separations (employing different feed compositions). 7. Ion exchange IonEx TA: Soumitra Choudhary 'Sam' The Ion exchange experiments will compare a variety of ion-exchange resins for the removal of Copper Sulfate from an aqueous solution. There will be four new resins available, all strong acid cation resins produced by Dow. These represent different particle sizes for the same resin. Another represents a different degree of cross-linking. And, finally, there is a product called, “Marathon”. Each new group is to choose a resin to compare to the prior results and to show and explain the differences. It is obviously required to understand the differences based on their composition and morphology, as extracted from DOW. In addition we have a new surface analyzer in the lab by which you can measure the surface areas for the different resins. One will need to understand the basic theory as it relates to the potential differences. Finally, you will compare your results to the theory and to the results from prior research groups. The theory and the data from prior studies will be part of your proposal. 8. pH Reactor Control pHControl TA: Sumeet Pandey This experiment involves the control of a liquid-phase reactor to neutralize acid-base streams. As in all control situations, the initial approach is to understand and analyze the reactor dynamics followed by the design and implementation of a control scheme. A buffer stream can also be introduced into the reactor as a disturbance. You have potential control over several reactor parameters: Liquid flows (in and out), Reactor volume, Reactor stirring, … etc. There are any of several control schemes that can be implemented from simple PID to MIMO. You are to choose a scheme, collect appropriate data on dynamics, Implement the scheme and evaluate the resultant controlled dynamics. 9. Polymer Injection Molding InjMold TA: Vikram Daga The obvious purpose of polymer injection molding is to produce a part (plastic dogbone or spiral) with certain properties. These properties are subject to testing by an Instron mechanical testing instrument (an assigned TA in PSE will run these) or to other tests you can devise. Normally, the goal is to produce the strongest part but it could also be to produce a part that breaks within a given region of force. There are several variables that can be manipulated in this process that change the strength, uniformity and/or mechanical performance of the final part. These are ideally suited to experimental design to optimize this process. We will have several polymers to choose from for extrusion. You will study one of these in contrast to the other polymers to be studied by other groups. 10. Polymer Extrusion Extrusion TA: Vikram Daga A new extruder has been added to the laboratory that will be more automated than in the past. You can control many parameters such different temperatures along the barrel of the extruder. The purpose of polymer extrusion is to produce a continuous strand of polymer of uniform dimension from pellets. Several dies of varying dimension are available. The conditions throughout the extruder control the nature of the product strand. This experiment should first employ experimental design to optimize the production process and its influence on dimension and uniformity for different die sizes. You will have several choices of polymer and will need to characterize the product (dimension and uniformity). A protocol should be developed for this. Die-swell can be a complicating factor for certain polymers under specific conditions. We may be able to develop access to DTA, differential thermal analysis, to characterize differences in the polymer crystallinity which will depend on process conditions. By employing polymers of different colors, you may be able to quantify the uniformity of the mixing in the extrusion process. Do Not start the extruder until the barrel has been heat up… you would then brake the pin and loose a period for experiments.