The development of low-volume continuous processes for the pharmaceutical industry requires a greater understanding of mixing in microreactors. In this paper, numerous commercially available micromixers are evaluated using the Villermaux–Dushman reaction scheme and the interaction by exchange with the mean (IEM) mixing model to quantify the mixing time. The work presents the mixing times as a function of flow rate and energy dissipation for mixers including T-mixers, Ehrfeld Mikrotechnik BTS micromixers, and Syrris Asia microchips.

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Phragmites australis (PHA) is a grass-type biomass, commonly known as reed grass, which has the potential to be a valuable energy and chemical feedstock due to its high yield (4.5-7 kg biomass m −2 year −1 ). It is demonstrated that the physicochemical properties and composition of phragmites can be altered by subjecting the feedstock to a combined acid hydrolysis at various level of acid concentrations and torrefaction pre-treatment processes. In this paper, we conducted fast pyrolysis on pretreated PHA, resulting in bio-oil with significantly higher selectivity towards levoglucosenone and appreciably reduced amounts of ketones and aldehydes being produced. The experiments demonstrated that 4% H 3 PO 4 acid hydrolysis and 220 • C torrefaction combined pretreatments prior to fast pyrolysis resulted in 17 times increase of relative selectivity to levoglucosenone in the bio-oil portion along with a reduction of ketones and aldehydes relative concentrations from 23% to 13%. Pyrolysis of pretreated PHA produced higher amount of biochar. The phosphorus-enriched biochar offers a potential usage for soil amendment or sorbent material. This study presents an opportunity to convert this underutilized feedstock into valuable bio-based products. Additional in-depth investigation is essential to gather more data for assessing the economic and sustainability features of the proposed process.

Fast pyrolysis is a thermochemical process which converts biomass into intermediate bio-oil and biochar products, which can be further processed to produce end products. Bio-oil is an organic liquid containing myriads of organic chemicals derived from the decomposition of cellulose, hemicellulose, and lignin components in lignocellulosic biomass. There are chemicals in bio-oil which are highly valuable as specialty chemicals, such as furfural, levoglucosan and levoglucosenone. Unfortunately, the amounts of these chemicals are typically too small, which makes it uneconomical to extract them from bio-oil. This work is focused on fast pyrolysis of pinewood, a well-known softwood used in paper industry. In this work, it was demonstrated that bio-oil containing higher fractions of furfural and levoguclosenone can be produced by treating pinewood feedstock with zinc chloride prior to pyrolysis. The batch pyrolysis studies by using a micropyrolyzer, a batch tubular reactor, and a thermogravimetric analyzer showed that the amounts of zinc chloride impregnated to pinewood feedstock significantly affect the yields of bio-oil and biochar products and the composition of chemicals in bio-oil. Increasing the concentration of zinc chloride solution used for pretreating the feedstock resulted in higher yields of biochar containing higher amount of the salt. Optimum concentrations of furfural and the two sugars in bio-oil product seemed to be obtained from pyrolysis of pinewood that was pretreated with 5wt% zinc chloride solution. Pretreatment with higher salt concentration reduced the concentration of levoglucosan but did not affect the other two valuable chemicals.