The development of biomass pyrolysis oil refineries is a very promising path for the production of biofuels and bioproducts from lignocellulosic materials. Given that bio-oil is a complex mixture of organic compounds, the production of valuable bioproducts may imply the use of different separation processes, such as distillation, selective condensation, crystallization based on melting points, liquid−liquid extraction or adsorption, and/or upgrading treatments, such as catalytic cracking or hydrodeoxygenation. In this context, the main objectives of this work are (1) to propose a simple but representative composition of the bio-oil, which can be used as a bio-oil surrogate, and (2) to determine selected thermodynamic, physical, and molecular properties of the organic compounds included in the bio-oil surrogate using different estimation methods and calculation procedures. These properties are critical temperature, critical pressure, critical volume, normal boiling point, enthalpy of vaporization, vapor pressure curves, normal melting point, enthalpy of fusion, heat capacities of gas, liquid, and solid, gas and liquid standard enthalpy of formation, gas standard Gibbs free energy of formation, Hansen solubility parameters, molecular volume, and molecular diameter. This group of properties has been selected for their possible application in the simulation or design of thermochemical, separation, and upgrading processes. Additionally, the suitability of the estimated thermodynamic properties and the proposed surrogate composition has been assessed by comparing experimental and literature data with the apparent enthalpy of formation of the bio-oil predicted from the weight-averaged contributions of the compounds as well as the heat required for the pyrolysis process at 500 °C.

The possibility of using ammonia (NH 3 ), as a fuel and as an energy carrier with low pollutant emissions, can contribute to the transition to a low-carbon economy. To use ammonia as fuel, knowledge about the NH 3 conversion is desired. In particular, the conversion of ammonia under pyrolysis conditions could be determinant in the description of its combustion mechanism. In this work, pyrolysis experiments of ammonia have been performed in both a quartz tubular flow reactor (900−1500 K) and a non-porous alumina tubular flow reactor (900−1800 K) using Ar or N 2 as bath gas. An experimental study of the influence of the reactor material (quartz or alumina), the bulk gas (N 2 or Ar), the ammonia inlet concentration (1000 and 10 000 ppm), and the gas residence time [2060/T (K)−8239/T (K) s] on the pyrolysis process has been performed. After the reaction, the resulting compounds (NH 3 , H 2 , and N 2 ) are analyzed in a gas chromatograph/thermal conductivity detector chromatograph and an infrared continuous analyzer. Results show that H 2 and N 2 are the main products of the thermal decomposition of ammonia. Under the conditions of the present work, differences between working in a quartz or non-porous alumina reactor are not significant under pyrolysis conditions for temperatures lower than 1400 K. Neither the bath gas nor the ammonia inlet concentration influence the ammonia conversion values. For a given temperature and under all conditions studied, conversion of ammonia increases with an increasing gas residence time, which results into a narrower temperature window for NH 3 conversion.

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The hydrodeoxygenation (HDO) of bio-oil at 350 °C and 200 bar in a batch reactor over a Ru/C catalyst has been studied experimentally with the aim of contributing to the understanding of the HDO reaction and its effect on the physicochemical properties of the organic liquid fraction obtained. Moreover, the effect of the catalyst loading ratio used in the HDO treatment and a previous stabilization stage carried out at 250 °C have also been assessed. Under the studied operational conditions, reactions of decarboxylation, HDO, polymerization, decarbonylation, methanation, demethylation, and pyrolytic lignin depolymerization took place during the HDO process. In these experiments, O was removed from the bio-oil mainly in the form of CO 2 (15−26 g of CO 2 •100 g −1 of dry bio-oil) and also as H 2 O (1.8−5.8 g of H 2 O•100 g −1 of dry bio-oil). The consumption of H 2 was between 0.75 and 1.0 g•100 g −1 of dry bio-oil. A comparison of the physicochemical properties of the raw bio-oil and the HDO organic phases shows that the major effects of HDO are a reduction in the O content from 34 to 13 wt %, an increase in the higher heating value (dry basis) from 24.3 to 35.5 MJ•kg −1 , lower polarity of the organic compounds determined by the significant increase in the hexane solubility, lower corrosiveness evidenced by the smaller total acid number and acid concentrations, and a marked change in the gas chromatography−mass spectrometry detectable compounds, increasing the presence of monophenols and cyclic ketones and decreasing the presence of levoglucosan, methoxyphenols, and furans. Electrospray ionization(±)−FTMS analyses of the raw bio-oil and the HDO liquid fractions show a widespread reduction of the O/C molar ratio of the compounds, an efficient deoxygenation and depolymerization of pyrolytic lignin, and a nondesirable increase in the range of molecular weights of the organic molecules after the HDO treatment.

This paper describes the architecture and implementation of a high-speed decompression engine for embedded processors. The engine is targeted to processors where embedded programs ure stored in compressed form, and decompressed at runtime during instruction cache rejill.The decompression engine uses a unique asynchronous variable decompression rate architecture to process Huffman-encoded instructions. The resulting circuit is significantly smaller than comparable synchronous decoders, yet has a higher throughput rate than almost d l existing designs. The 0 . 8~ layout is all full-custom and contains predominantly dynamic domino logic. The top-level control, as well as several small state machines, are implemented using asynchronous logic. The design operates without a user-supplied clock. Simulations using Lsim show average throughput of 32 bits/45 ns on the output side, corresponding to about 480 Mbit/sec on the input side. The chip has been m,anufactured by MOSIS; tests show that the asynchronous implementation operates correctly, with an average throughput exceeding simulations: 32 bits/39 ns on the output side, corresponding to about 560 Mbit/sec on the input side. This speed is acceptable for our application. The area of the design (excluding the pad-frame overhead) is only 0.75 mm2. The design is the first fabricated chip for an instruction decompression unit for embedded processors.