Chemical recycling of polystyrene with microwave pyrolysis, Pilippe Leclerc
Production of Value-Added Chemicals Biomass-Based, Sherif Farag
Upgrading of oils from household waste Microwave Pyrolysis, Soumaya Benzennou
|Investigation of the solid-state reaction of Li4Ti5O12 for lithium-ion batteries anode material|
|Spinel lithium titanium oxide (Li4Ti5O12) is regarded as the most promising anode material for lithium-ion batteries due to its long cycling life, high safety performance, and fast charging property. Although Li4Ti5O12 possesses many excellent properties, the higher price of nano-spinel Li4Ti5O12 not only rises the cost of battery systems, but limits its application as well. The main reasons for its high cost are attributed to the high synthesis temperature and complicated processes of solid-state reaction synthesis which is considered as the most suitable method for the large-scale production. Clear understanding of the fundamentals of the synthesis process is very important to control production conditions, minimize the energy consumption and lower synthesis cost. We investigated the kinetics of solid-state reaction between TiO2 and Li2CO3 and found that tailoring the particle size of TiO2 could decrease the synthesis temperature.|
|Catalytic Pyrolysis of Biomass and waste for the Production of Value-added Chemicals|
|Thermochemical decomposition is the most promising technique can deal with the huge amount of biomass and wastes produced worldwide. In the scientific literature, noticeable efforts have been made to enhance the yield of the pyrolysis oil since bio-oil is the most valuable product compared to bio-char and bio-gas. However, improving its quality is still facing many technical and economic limitations. Developing an active catalytic agent that can improve the composition and the chemical structure of the pyrolysis oil and, at the same time, does not negatively impact the obtained yield would avoid many issues in the current technologies.Herein, the applied methodology includes investigating the influence of several catalysts, different in the physical and chemical properties, on the yield and composition of the pyrolysis products. To do so, a strategic plan to reveal the effect of the process parameters in the presence of each catalyst is designed and, then, performed to discover the most effective catalytic agent and its optimum pyrolysis conditions. A chemical process to convert biomass and wastes to an end-product is also developed, and eventually, its technical and economic aspects are evaluated.
Indeed, such a research project would lead in improving the understanding of many complex reactions that have taken place during the decomposition of such complex feedstocks. This aspect, consequently, would provide insights for better controlling reaction mechanisms and, in turn, enhance product selectivity. Moreover, the key findings of this trial can significantly contribute to necessary areas of chemicals from biomass and wastes, waste-to-energy, renewable energy, and greenhouse gas emission reduction in the interest of many countries in the world. The last and not least, the applied approach herein can deal with the current challenges, address the growing list of environmental concerns, and take advantage of the rapid increase in price and demand of fossil fuel-based energy and products.
Microwave-assisted pyrolysis of E-waste for precious metals recovery and production of value-added bio-products
|MOHAMED SHERIF KHALIL|
|Management of the rapidly growing and highly hazardous electronic waste stream is one of the main environmental challenges currently facing Canada, and most other countries. According to the United Nations Environment Programme (UNEP), between 20 and 50 million metric tons of e-waste are disposed of globally every year, and this is predicted to increase to between 40 and 70 million tons per year by 2015. Within Canada, volumes of e-waste are reportedly increasing by 4% each year. One source has estimated that more than 5 million computers and monitors alone are thrown away annually by Canadian households and businesses. These form only part of a much larger e-waste stream that includes mobile phones, televisions, office equipment and white goods.
The safe and efficient management of the e-waste stream presents particular challenges due to the complex nature of most e-products, which typically include high levels of hazardous substances such as lead, mercury and cadmium. Environmental hazards such as toxic emissions also arise as a by-product of e-waste disposal or recycling processes. However, many e-waste products also contain valuable and scarce materials such as gold, silver, platinum and copper, and their effective recovery for resale and reuse represents a potentially lucrative business activity.
Recycling methods currently in use are not particularly efficient or cost-effective. The processes involved are still quite labour-intensive, involving dismantling products by hand to extract valuable components, or remove harmful substances before the waste is sent for end-processing using automated methods. New techniques may improve the efficiency of recycling and help ensure that the high-value outcomes of recycling outweigh the costs involved.
|Chemical recycling of polystyrene with microwave pyrolysis|
|According to the EPA , less than 10% of the plastic produced in the USA is recycled. The principal reason for this is the incapacity to reprocess the plastic waste in such way that the output can be re-used into virgin plastic applications, such as production of food and beverage containers or other consumer goods. Although technologies exist for PET where it can reintroduce PET into some FDA compliant applications , it is not the case for most of other post-consumer plastics, such as polystyrene, especially when they are contaminated, e.g., organic materials and paints. In the USA, 1.3% of the 2 270 thousand of ton of polystyrene generated was recovered in 2013 . My research wants to show how microwave pyrolysis can be applied for recycling post-consumer polystyrene and allow it to be re-used in FDA compliant applications. The mechanism of action is simple: the use of microwave pyrolysis breaks down the post-consumer polystyrene into monomers that are then re-introduced in the existing ecosystem of refining and polymerization industries. What differentiates microwave pyrolysis from other conventional pyrolysis processes is the heating rate which is fast because energy is transferred on a volumetric basis, whereas other conventional approaches are slower because the heating occurs on a conduction/convection basis. Also, the pyrolysis step allows handling of a broader amount of contaminants such as organics, fibres and minerals compared to mechanical/physical technologies.
 United States Environmental Protection Agency (EPA), 2015.
 United States Food and Drug Administration (FDA), 2015.
|Production of Value-Added Chemicals Biomass-Based|
|The forest industry in Canada is one of the cornerstones of the national economy at $80 billion per year, and provides 900,000 jobs across the country. Presently, however, this industrial sector is at a crossroads as it is facing unexpected challenges due to competition from low-cost sources of wood and a decline in demand. The production of value-added products, in addition to traditional commodity, is a path to ensure a sustainable future for the industry.
In the papermaking process, lignin is produced in huge quantities, mostly is combusted. Indeed, lignin is a complex, heterogeneous aromatic polymer that makes it looks suitable for the production of many products. Thus, providing a suite of technologies for developing high-value lignin-based products will benefit traditional paper mills by diversifying the range of products they can produce. This approach, consequently, addresses the challenges faced by the Canadian forest industry.
Thermo-chemical treatment is the most promising technique to convert lignin into high-value products, for it is the only technique that can deal with the huge quantity of lignin produced worldwide. In this regard, we have been conducting a series of investigations for the pyrolysis of lignin, covering the technical and economic aspects.
|Upgrading of oils from household waste Microwave Pyrolysis|
|Household waste is affecting everybody’s life. Therefore, more and more people are taking actions in order to reduce their debris while municipalities attempt to enhance their treatment processes. However, these efforts are not sufficient enough: only 17% of the waste is effectively recycled worldwide, compost does not take in charge all the waste (around 9%), and more than 75% ends up in landfills and incinerators. In our research group, we opt for an in-situ treatment of the waste: neighborhoods, restaurants, and even individuals are to be involved in the treatment of their own litter. We chose to build a microwave based apparatus to pyrolyse the waste. However, the yielded liquids are not competitive with the fossil fuels because of their high oxygen content, immiscibility with hydrocarbons, high viscosity, high acid tenor, aging, etc.
Hence, the objective of this project is to optimize the entire process in order to produce oils that would not require sophisticated post-treatment. We focus on lignocellulosic waste. The proposed method is to first work on the pre-pyrolysis by adding in the pyrolysis compartment (1) calcium oxide for further cracking of the long chain and acid capturing/ neutralization (2) HDPE to react as a hydrogen donor for hydrodeoxygenation. We will also treat the hot vapors online with the pyrolysis by adding a red mud based catalyst –developed in our lab –at the exit of the pyrolysis compartment, using microwaves to heat up the catalytic hydrogenation and the gases from the pyrolysis (hydrogen and hydrogen donors). And finally a post-pyrolysis procedure is planned to be executed where vapors are to be condensed at distinct time/ temperature/ pressure to separate water and water soluble components from added value chemicals.