Pongamia, a leguminous, oilseed-bearing tree, is a potential resource for renewable fuels in general and sustainable aviation fuel in particular. The present work characterizes physicochemical properties of reproductive materials (seeds and pods) from pongamia trees grown in different environments at five locations on the island of Oahu, Hawaii, USA. Proximate and ultimate analyses, heating value, and elemental composition of the seeds, pods, and de-oiled seed cake were determined. The oil content of the seeds and the properties of the oil were determined using American Society for Testing and Materials and American Oil Chemist's Society methods. The seed oil content ranged from 19 to 33 wt % across the trees and locations. Oleic (C18:1) was the fatty acid present in the greatest abundance (47 to 60 wt %), and unsaturated fatty acids accounted for 77 to 83 wt % of the oil. Pongamia oil was found to have similar characteristics as other plant seed oils (canola and jatropha) and would be expected to be well suited for hydroprocessed production of sustainable aviation fuel. Nitrogen-containing species is retained in the solid phase during oil extraction, and the de-oiled seed cake exhibited enrichment in the N content, ∼5 to 6%, in comparison with the parent seed. The pods would need further treatment before being used as fuel for combustion or gasification owing to the high potassium and chlorine contents.

Proteasomes of pathogenic microbes have become attractive targets for anti-infectives. Coevolving with its human host, Mycobacterium tuberculosis (Mtb) has developed mechanisms to resist host-imposed nitrosative and oxidative stresses. Genetic deletion or pharmacological inhibition of the Mtb proteasome (Mtb20S) renders nonreplicating Mtb susceptible to reactive nitrogen species in vitro and unable to survive in the lungs of mice, validating the Mtb proteasome as a promising target for anti-Mtb agents. Using a structure-guided and flow chemistry-enabled study of structure-activity relationships, we developed phenylimidazole-based peptidomimetics that are highly potent for Mtb20S. X-ray structures of selected compounds with Mtb20S shed light on their selectivity for mycobacterial over human proteasomes.

The effects of processing conditions (closed versus open reactor, pressure, temperature, soaking time, biomass loading, heating rate, and fuel particle size) on product yields and char properties from constant-volume carbonization are reported. Increasing the pretest, inert-gas, system pressure from 0 to 2.17 MPa did not significantly affect product yields or char proximate analysis results. Increasing the reaction time from 30 to 190 min and the temperature in the 300-550 degrees C range improved fixed-carbon contents and reduced volatile matter while maintaining or slightly increasing the fixed-carbon yields. In contrast to flash carbonization or traditional carbonization observations where larger particles produce beneficial effects, constant-volume carbonization produced equal or higher fixed-carbon contents and yields from smaller biomass particles. This offers possibilities that smaller-sized, lower-grade biomass can be used to produce high, fixed-carbon yield charcoal. Under certain processing conditions, the particulate biomass underwent a transient plastic phase transition that produced a single solid piece of final char. The roles of processing conditions in the formation of this transient plastic phase are also discussed.

There is increasing interest in developing biobased alternative jet fuels to meet rising aviation demand and address environmental concerns. Uncertainty of oil prices, issues of energy security, and rising greenhouse gas concentrations have spurred the development and acceptance of alternative, economically viable, environmentally sustainable production pathways. The objectives of this study were to review alternative jet fuel feedstock candidates and relevant conversion data to provide a baseline of information to be accessed and built upon in developing production scenarios in Hawai'i and other tropical regions bounded by the Tropic of Cancer in the northern hemisphere and the Tropic of Capricorn in the southern hemisphere. Seventeen plants that produce oil, fiber, and sugar feedstocks were identified, and information on cultural practices, yield ranges, invasiveness, and mechanization status was assembled. Available data on pretreatment requirements and conversion processes for the 17 feedstocks, including mass and energy balances, product and byproduct yield and quality, and scale requirements/unit sizes, were reviewed. This effort seeks to inform the development and design of alternative jet fuel production along regional supply chains in Hawai'i and other locations in the tropics.

A good understanding of the mechanisms for non-catalytic depolymerization of lignin via transfer hydrogenation is essential in order to achieve process optimization.

A novel carbonization process that realizes near-theoretical fixed-carbon yields in similar to 3 h is presented. Norwegian spruce and birch sawdusts were carbonized in a hermetically sealed reactor at an initial nitrogen pressure of 0.1 MPa. During a carbonization test, the reactor vessel retained all pyrolytic products inside the hot reaction zone invoking high pressures as the temperature was raised. Given the elevated partial pressures of volatiles and their extended residence times, secondary, heterogeneous, char-forming reactions between the hot solid and the tarry vapors appeared to be promoted. This resulted in charcoals with a remarkably high fixed-carbon yield, noncondensable gases mainly composed of CO, and negligible amount of free tars. This work presents a reproducibility study on the experimental method and explores the effects of heat-treatment temperature, particle size, mass loading, and immersion time on product distributions and charcoal properties. Proximate and elemental analyses, heating values, and scanning electron microscopy images of charcoal are presented. Higher heat treatment temperatures (from 300 degrees C to 400 degrees C), smaller grains (from <2 mm to <0.2 mm), longer immersion times (from 30 min to 190 min), and greater mass loadings (from 130 g of biomass per liter of reactor to 165 g of biomass per liter of reactor) intensified wood devolatilization without losing charcoal fixed-carbon yields. Final charcoal products had lower volatile matter contents and improved fixed-carbon contents. Temperature produced the strongest effect, transforming the virgin spruce with a fixed-carbon content of 15% to charcoals with fixed carbon contents of 52% at 300 degrees C and 73% at 400 degrees C. The increase in temperature resulted in a transient plastic phase that changed the char appearance from loose, particulate matter to a smooth, shiny solid product with the appearance of coke.

This chapter describes analytical chemical methods used to characterize high-mass materials found in liquids and tars from coal processing in crude petroleum fractions such as asphaltenes and in liquids from the conversion of biomass into liquid fuels. Methods described include size exclusion chromatography with different solvents, mass spectrometric method including laser desorption, nuclear magnetic resonance, fractionation techniques, vapour pressure osmometry, UV-fluorescence and Fourier Transform infrared spectroscopy. Significant developments in these fields are described. Comparison with Fourier Transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) reveals significant shortcomings with that method in application to petroleum residues. The high-mass components of biomass tars have previously been ignored.

X-ray fluorescence (XRF) spectroscopy was usedto assess the effectiveness of various mild pretreatMent methods for improving the fuel quality of banagrass, a tropical grass. Three types of pretreatment were used with increasing levels of severity: (i) S1 involves dewatering (pressing) only, (ii) S2 where the sample is pressed and leached, and (iii) S3 where pressing-leaching-pressing process is used. In addition, the influence of particle size (2 or 60-80 mm), leaching water temperature (25 or 75 degrees C), and leaching time (1 or 3 min) On the extraction of inorganic elements was examined`. The results show that the S3 pretreatment is the most effective and that reducing the particle size has,a more significant effect than increasing leaching temperature Or time. Using a 2 Aim particle size at 75 degrees C for 3 min produced the greatest effect, removing 50-60 wt % of the Na, similar to 65 wt % Mg,similar to 90 wt % P,similar to 90 wt % wt % K, similar to 55 wt % S, and similar to 95 wt % Cl. USing dewatering alone (S1) to pretreat the banagrass was the least effective approach. The S2 pretreatment produced results that are midway between the S1 and S3 results. However, using small particle's with the S2 method gives similar results tolprocessing large particles using the =S3 approach.

This introductory chapter provides a brief outline of the material covered in this book. Two areas of research concerning the thermochemical processing of coal and lignocellulosic biomass have been described. The development of experimental methods for exploring the mechanics of thermal breakdown in lignocellulosic biomass and coal has been reviewed. The second area covers the development of methods for the analytical characterization of heavy hydrocarbon liquids, produced by the thermochemical reactions of solid fuels. The scope of the analytical work extends to the study of molecular mass distributions and the structural characteristics of petroleum-derived heavy fractions. The chapter provides a brief historical review of solid fuel utilisation and outlines recent trends in renewable and fossil fuel consumption.

Mechanical dewatering and leaching were used to process freshly harvested banagrass (Pennisetum purpureum X Pennisetum glaucum) and improve fuel properties relevant to thermochemical conversion. A factorial, 23 experiment determined the effects of process operating parameters: particle size (1 mm and 80 mm), rinse water temperature (25 degrees C and 75 degrees C), and rinse duration (1 min and 3 min). Characterization of the samples from the process included moisture and ash contents of solid samples, potassium (K) and chlorine (Cl) contents of solid and liquid samples, and chemical oxygen demand, total solids, and total suspended solids of liquid samples. These were used to assess the effectiveness of treatment on reducing K and Cl in the processed material, estimate material/energy losses associated with the processing, and identify further treatment requirements and opportunities for material recovery. The effects of particle size, rinse water temperature, and their interaction indicate that processing with low-grade hot water (75 degrees C) can improve K and Cl removal by over 10% compared to treatment using ambient temperature water for larger particles (80 mm). The former could result in reduced capital and operating costs for size reduction, as well as reduced material losses during processing. (C) 2017 Elsevier Ltd. All rights reserved.

This chapter describes reactor design methods that attempt to bridge the gap between bench-scale fuel-characterization tests and conditions prevailing in thermochemical fuel conversion processes. It focuses on high-pressure experiments in inert atmospheres (pyrolysis), in hydrogen (hydropyrolysis and hydrogasification), as well as gasification in steam-air and steam-oxygen atmospheres. Furthermore, it examines the effects of high-pressure on the morphologies and reactivities of the solid products—the chars. Gasification is a mature art and vast numbers of experiments have been done in the past, to investigate the pyrolysis and gasification of coals and biomass materials. Most modern gasifier designs are based on short residence time fluidized-bed or entrained flow reactors, where heating rates are high and exposure to reaction conditions is short. Mostly, solids exit from the reactors in a matter of seconds or, at most, tens of seconds. The requirements arising from the expanded use of fluidized and entrained flow designs have substantially changed the face of solid fuel characterization. The emerging designs of fuel characterization tests are driven by the necessity to match rapid processing requirements. Another critical factor is the recognition that the outcomes of these tests depend on reactor configuration and reaction conditions during prior thermal breakdown, as well as the original compositions of the fuels.

This chapter focuses on pyrolysis and gasification work at high pressure. The design of reactors for performing experiments under inert gas and hydrogen as well as gasification work in high-pressure CO2-steam-air (or oxygen) mixtures will be described. The need for discriminating between fundamental sample behaviour and effects due to sample and reactor configuration will be discussed in the framework of high-pressure reactor design. The work primarily aims to characterise the thermochemical reactions of biomass and coal. An attempt is also made to establish a level of comparability between reaction conditions in bench-top reactors and conditions prevailing in large-scale fuel processing plants. The second aim translates into designing bench-scale reactors that are capable of mimicking the time-temperature-pressure trajectories of individual fuel particles, within designated zones of pilot or plant scale equipment.