Interactive Data Visualization Tool to Analyze Word Count Frequencies Over Time

This research project will be able to display word frequencies through data visualizations. By accessing the internet, a user will be able to load in a document or text and the program will parse through and figure out the frequencies of words. The program will then provide the user with several graphical interpretations of the word frequencies. Some data visualizations models that will be used are trend lines, stack lines, and other forms. A goal of this project is to create a useful interactive interface that allows for the user to draw evidence about word trends over time. The program will be used by a researcher who is interested in word usage in educational legislation

Crystallisation of bis(2-hydroxyethylene) terephthalate as a part of a bottle-to-bottle recycling concept for poly(ethylene terephthalate)

The chemical recycling of poly(ethylene terephthalate (PET) is very attractive as PET bottle waste provides an abundant clean material with low levels of additives. One of the most promising processes is glycolysis, which depolymerises PET in the presence of ethylene glycol. For this process, it is necessary to think through the whole concept from the waste material to the newly polymerised virgin polymer. Most research ends with determining the yield of bis(2-hydroxyethyl)terephthalate (BHET) after glycolysis. Some research includes anti-solvent crystallisation with water to separate BHET from ethylene glycol. However, the subsequent separation of water and ethylene glycol is an energy intensive process. Therefore, this work aims at the direct crystallisation of BHET from ethylene glycol. For this reason, the crystallisation of BHET was investigated experimentally. Crystallisation was simulated using gPROMS Formulated Products with aim of estimating kinetic parameters and using these to optimise an industrial process. Kinetic parameters were determined by model validation including primary and secondary nucleation and crystal growth. The best fitting set of kinetic parameters was used to optimise BHET crystallisation in batch and continuous mode by minimising equipment costs. Impeller parameters were found to have a great influence on crystallisation performance. Ultimately, the continuous and batch processes gave comparable results in terms of equipment cost, with the batch process giving larger crystals and higher yields, but the continuous process requiring a smaller crystalliser

Organocatalytic Glycolysis of Polyethylene Terephthalate and Product Separation by Membrane Filtration

In recent years, researchers have developed metal-free ionic organocatalysts for PET depolymerisation that have exhibited good catalytic activity, thermal stability and low environmental toxicity. This work aims to study the scalability, reaction kinetics and product separation of the chemical recycling reaction as a step towards developing a scalable process. An ionic organocatalyst comprising 1,8-diazabicyclo(5.4.0)undec-7-ene (DBU) and para-toluene sulfonic acid (pTSA) was selected as a potential glycolysis catalyst. The process was successfully scaled by a factor of 40, with complete conversion of PET achieved in 72 minutes (10g PET, 25 mol% catalyst, 180 oC, 20 equiv. ethylene glycol) in a batch reactor. The glycolysis kinetics were found to obey a modified shrinking core model, in which PET ester bonds are cleaved at the surface of the PET particles and the activation energy was experimentally calculated to be 61-66 kJ mol-1. The kinetic model was adapted to account for product inhibition, where hydrolysis of bis-hydroxyethyl terephthalate (BHET) by extraneous water led to the formation of carboxylate moieties which were found to deactivate the catalyst and inhibit the glycolysis reaction. Furthermore, DBU:pTSA can be separated from ethylene glycol by nanofiltration using a commercial TS40 membrane at elevated temperatures between 80 and 120 °C. A rejection of 93% can be achieved at 2.24 MPa independent of temperature, while the highest flux of 17.7 kg m-2 s-1 was obtained at 120 °C. The presence of BHET only slightly reduced the catalyst rejection, but the flux dropped to 7.4 kg m-2 s-1. As BHET only resulted in a rejection of 41%, nanofiltration offers the possibility of separating both catalyst and BHET at elevated temperatures

“Control-Alt-Delete”: Rebooting Solutions for the E-Waste Problem

A number of efforts have been launched to solve the global electronic waste (e-waste) problem. The efficiency of e-waste recycling is subject to variable national legislation, technical capacity, consumer participation, and even detoxification. E-waste management activities result in procedural irregularities and risk disparities across national boundaries. We review these variables to reveal opportunities for research and policy to reduce the risks from accumulating e-waste and ineffective recycling. Full regulation and consumer participation should be controlled and reinforced to improve local e-waste system. Aiming at standardizing best practice, we alter and identify modular recycling process and infrastructure in eco-industrial parks that will be expectantly effective in countries and regions to handle the similar e-waste stream. Toxicity can be deleted through material substitution and detoxification during the life cycle of electronics. Based on the idea of "Control-Alt-Delete", four patterns of the way forward for global e-waste recycling are proposed to meet a variety of local situations