Dual mode plasma UV microreactor for ozonolysis and hydrogenation green chemistry

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Ozone is a powerful oxidizing agent but is conventionally expensive to produce, requiring high voltage operation with high power draw, typically produced under vacuum with pure oxygen, cryogenically stored, and unspent, poorly mixed ozone is a hazard that requires expensive, dedicated plant room to destroy. Consequently, ozone is only used when there is no reasonable alternative.We have developed a method for producing ozone at room temperature, atmospheric pressure, from air feedstock, with low voltage operation, high yield, and low power consumption (approximately 1/10th the power draw of conventional plasma reactors with the same throughput), using plasma microreactors. In order to increase the volumetric flow rate, we have multiplexed the microreactors in a dosing lance that delivers the ozone directly into aqueous solution, with dispersal by microbubbles. We are developing this technology for use in the water sector, for applications in water purification and wastewater treatment, where energy efficiency in the production and dispersal of ozone is a strong driver. Our microbubble approach for dispersal should also improve dispersal rates by an order of magnitude, thus minimizing wastage and associated hazards - the level of dosing can be tuned so that all the ozone or intermediates in the production of ozone can be dissolved and consumed in reaction.Plasmolysis formation from steam has always been viewed as an expensive route to hydrogen production, with estimates of 50% efficiency with conventional plasma reactors, trailing behind electrolysis and about on par with thermochemical cycles. In laboratory trials with plasma microreactors, we generated hydrogen from steam with the same conditions as the ozone reaction: room temperature, atmospheric pressure, with low voltage operation,, and low power consumption. Given that it is impossible to achieve a tenfold energy efficiency savings over conventional plasmolysis, the logical conclusion is that some of the heat of reaction is drawn from the steam, and the remainder is the electricity draw. This suggests the potential for substantial energy savings wherever there is a source of waste steam or waste heat to raise steam.Of course, plasmolysis produces H2 and O2 simultaneously and with no space segregation, as in electrolysis. Hence there is a need to separate the products so as to use them separately. Microbubbles provide a sufficient separation due to the fact that hydrogen is practically insoluble in water - oxygen is 25-fold more soluble at room temperature. Hence microbubbles with a tall enough head of water will be practically stripped of oxygen, thus hydrogen rich when they burst at the gas-liquid interface upon rising through a column of water. Since aeration of many wastewaters is a desired processing step, there is every possibility that the hydrogen separation can be achieved while integrated with other processing operations on an industrial plant.With a cheap source of ozone for ozonolysis reactions and hydrogen for hydrogenation reactions, the dosing lance has the potential to yield co-products from biomass processing economically - precursors for bioplastics, nutraceuticals, fine chemicals and pharmaceuticals - from the waste products of agriculture, pulp and paper processing, algal biofuels and biodiesel production, for instance. Although currently petroleum production is highly profitable for the fuel, historically, the introduction of petrochemicals from the bottom of the barrel enormously enhanced the profitability of petrol refining. In order to make bioprocessing to biofuels profitable (and hence sustainable) a similar set of profitable co-products may be necessary. This proposal aims to construct the robust prototype for industrial scale processing of the dosing lance and assess its economic potential for producing co-products.