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Continuous feeding, processing, and handling of biomass powders is pivotal to the economic viability of integrated biorefineries. However, current challenges associated with the operational reliability of bulk solids handling and transport greatly impact the process economics and ultimately the widespread commercialization of integrated biorefineries. In this work, we examine the effect of moisture and feedstock variability on the flow behavior of corn stover biomass particles. The total flow energy, compressibility, shear properties, and wall friction angles were measured for corn stover samples A and B containing 0%, 15%, 25%, 50%, and 75% (mass fraction) moisture contents using a FT4 powder rheometer. In general, the flowability of both A and B was reduced when moisture was present as indicated by the stability and variable flow rate, compressibility, and shear tests. The 15% moisture sample had the highest flow energy, revealing the interplay between the increased surface tension and looser packing both of which were caused by liquid bridging. The 75% moisture sample had the highest compressibility and the lowest flowability factor (ffc). The trend in wall friction angle was found to be dependent upon the surface hydrophobicity of the wall material. The wall friction angle on the hydrophilic, stainless-steel surface increased with moisture and therefore poses additional handling challenges. On the other hand, the wall friction angle on the hydrophobic polymer surfaces were the lowest for samples with intermediate moisture contents. Sample B had greater bulk density, smaller compressibility, and greater flowability than the sample A, as suggested by the compressibility and shear tests. The wall friction angle of sample B was higher than or equal to that of sample A depending on both the type and the surface roughness of the wall material.

Sugar upgrading to commodity chemicals has become prevalent over the last decades, owing in part to the potential of Lewis acid catalysts, in particular Sn-Beta zeolites. Sn-Beta has shown to possess high activity for the conversion of glucose to fructose as well as smaller molecules such as α-hydroxy esters (methyl lactate and methyl vinyl glycolate) and trioses (dihydroxyacetone, glyceraldehyde, pyruvaldehyde). Despite its promising kinetic potential, drawbacks that hinder it from being an industrially-used catalyst include the relatively low amount of Sn capable of being incorporated and the requirement of fluoride media to successfully synthesise Sn-Beta. Thus, top-down methods such as solid-state incorporation (SSI) has been of great interest for hard-to-incorporate heteroatoms such as Sn at higher wt. %. With this in mind, this thesis begins with an in-depth mechanistic study in the SSI of Sn-Beta, observing the acetate-zeolite interaction/evolution from the initial mechanochemical step to the ramp rate, both in inert gas flow and air using in situ spectroscopic techniques (Chapter 3). Furthermore, an optimised protocol for the heat treatment is obtained, having no negative impact in the kinetic performance of the zeolite. Chapter 4 investigates the influence of using different initial precursor (B, Fe, Ga, Al) for the zeolites’ subsequent SSI. Tests were done with glucose isomerisation as well as retro-aldol fragmentation in continuous flow. Following this, Chapter 5 demonstrates the application of a different type of Lewis acid catalyst: metal-organic frameworks (MOFs). The MOFs i.e., UiO-66(Zr) were studied in different polar solvents under continuous flow to understand their stability and were subsequently tested for disaccharide (lactose) isomerisation, a substrate which would typically not be possible to upgrade using conventional zeolites. Lactose isomerisation was done using binary mixtures of alcohol/water to successfully carry out the reaction. Chapter 6 sets out to carry out the SSI protocol, conventionally done in hydroxide-assisted zeolites, in fluoride-assisted zeolites. Tests were conducted firstly in a commercial, hydroxide-assisted zeolite using an alkaline media along with a pore directing agent at various temperatures. Thereafter, SSI protocol was conducted for three fluoride zeolites (Hf-, Sn-, Zr-) using the same conditions. Lastly, Chapter 7 discusses the results acquired as well as any pertaining challenges which might have been left open due to aforementioned results.