There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

1.0. Introduction 4044 2.0. Biomass Chemistry and Growth Rates 4047 2.1. Lignocellulose and Starch-Based Plants 4047 2.2. Triglyceride-Producing Plants 4049 2.3. Algae 4050 2.4. Terpenes and Rubber-Producing Plants 4052 3.0. Biomass Gasification 4052 3.1. Gasification Chemistry 4052 3.2. Gasification Reactors 4054 3.3. Supercritical Gasification 4054 3.4. Solar Gasification 4055 3.5. Gas Conditioning 4055 4.0. Syn-Gas Utilization 4056 4.1. Hydrogen Production by Water−Gas Shift Reaction 4056

/pdf/synthesis-of-transportation-fuels-from-biomass-chemistry-3sckhzoqoz.pdf

Synthesis of transportation fuels from biomass: chemistry, catalysts, and engineering.

Sustainable production of renewable energy is being hotly debated globally since it is increasingly understood that first generation biofuels, primarily produced from food crops and mostly oil seeds are limited in their ability to achieve targets for biofuel production, climate change mitigation and economic growth. These concerns have increased the interest in developing second generation biofuels produced from non-food feedstocks such as microalgae, which potentially offer greatest opportunities in the longer term. This paper reviews the current status of microalgae use for biodiesel production, including their cultivation, harvesting, and processing. The microalgae species most used for biodiesel production are presented and their main advantages described in comparison with other available biodiesel feedstocks. The various aspects associated with the design of microalgae production units are described, giving an overview of the current state of development of algae cultivation systems (photo-bioreactors and open ponds). Other potential applications and products from microalgae are also presented such as for biological sequestration of CO 2 , wastewater treatment, in human health, as food additive, and for aquaculture.

/pdf/microalgae-for-biodiesel-production-and-other-applications-a-54vmwufrsu.pdf

Microalgae for biodiesel production and other applications: A review

Biomass is an important feedstock for the renewable production of fuels, chemicals, and energy. As of 2005, over 3% of the total energy consumption in the United States was supplied by biomass, and it recently surpassed hydroelectric energy as the largest domestic source of renewable energy. Similarly, the European Union received 66.1% of its renewable energy from biomass, which thus surpassed the total combined contribution from hydropower, wind power, geothermal energy, and solar power. In addition to energy, the production of chemicals from biomass is also essential; indeed, the only renewable source of liquid transportation fuels is currently obtained from biomass.

The Catalytic Valorization of Lignin for the Production of Renewable Chemicals

Biofuels produced from various lignocellulosic materials, such as wood, agricultural, or forest residues, have the potential to be a valuable substitute for, or complement to, gasoline. Many physicochemical structural and compositional factors hinder the hydrolysis of cellulose present in biomass to sugars and other organic compounds that can later be converted to fuels. The goal of pretreatment is to make the cellulose accessible to hydrolysis for conversion to fuels. Various pretreatment techniques change the physical and chemical structure of the lignocellulosic biomass and improve hydrolysis rates. During the past few years a large number of pretreatment methods have been developed, including alkali treatment, ammonia explosion, and others. Many methods have been shown to result in high sugar yields, above 90% of the theoretical yield for lignocellulosic biomasses such as woods, grasses, corn, and so on. In this review, we discuss the various pretreatment process methods and the recent literature that...

http://ucce.ucdavis.edu/files/datastore/234-1388.pdf

Methods for Pretreatment of Lignocellulosic Biomass for Efficient Hydrolysis and Biofuel Production

Role of side‐chain hydroxyl groups in pyrolytic reaction of phenolic β‐ether type of lignin dimer was studied with several regiospecifically methylated dimers under the pyrolysis conditions (N2/400°C/1 min). Methylation of both Cα‐ and Cγ‐hydroxyl groups reduced the Cβ‐O cleavage reactivity up to the level of the non‐phenolic type. To maintain the high reactivity of guaicylglycerol‐β‐guaiacyl ether, at least one hydroxyl group was required in the side‐chain. These results indicate that one hydroxyl group at Cα‐ or Cγ‐position acts as a hydrogen donor during pyrolysis. Influence on the product formation also indicated that the hydrogen bond types affect the reaction sequences between the Cγ‐elimination followed by the Cβ‐O cleavage and the Cβ‐O cleavage via quinone methide intermediate.

Role of Side‐Chain Hydroxyl Groups in Pyrolytic Reaction of Phenolic β‐Ether Type of Lignin Dimer

https://repository.kulib.kyoto-u.ac.jp/dspace/bitstream/2433/203653/1/j.fuel.2015.10.117.pdf

Renewable diesel production from rapeseed oil with hydrothermal hydrogenation and subsequent decarboxylation

Softwood (Cryptomeria japonica) and hardwood (Fagus crenata) were treated in supercritical water (380°C, 100 MPa) for 8 s. The treated woods were fractionated to the water-soluble portion, methanol-soluble portion, and methanol-insoluble residues. For the methanol-soluble portion, which mainly consisted of lignin-derived products, gel permeation chromatography (GPC) and gas chromatographic-mass spectrometric (GC-MS) analyses were conducted to clarify the molecular weight distribution and to identify the monomeric products, respectively. GPC analysis revealed that the methanol-soluble portion contains monomeric and some oligomeric products. GC-MS analysis identified 19 guaiacyl compounds in the methanol-soluble portion from softwood, and 15 syringyl monomeric compounds in the methanol-soluble portion from hardwood. The structures of identified products included not only phenyl propane (C6—C3) units but also C6—C2 and C6—C1 units. In addition, the infrared spectra suggested that the methanol-soluble portion maintains the typical structure of lignin, although it is rich in condensed-type linkages with some changes in the propyl side chain. These results indicate that the supercritical water treatment cleaves not only ether linkages but also part of the propyl chains in lignin to give various aromatic compounds.

GC-MS and IR spectroscopic analyses of the lignin-derived products from softwood and hardwood treated in supercritical water

https://repository.kulib.kyoto-u.ac.jp/dspace/bitstream/2433/240781/1/j.carres.2006.06.014.pdf

Thermal stabilization of levoglucosan in aromatic substances.

http://repository.kulib.kyoto-u.ac.jp/dspace/bitstream/2433/87776/1/j.fuel.2009.01.002.pdf

Shiro Saka

Papers

Role of Side‐Chain Hydroxyl Groups in Pyrolytic Reaction of Phenolic β‐Ether Type of Lignin Dimer

Renewable diesel production from rapeseed oil with hydrothermal hydrogenation and subsequent decarboxylation

GC-MS and IR spectroscopic analyses of the lignin-derived products from softwood and hardwood treated in supercritical water

Thermal stabilization of levoglucosan in aromatic substances.

Effect of CO2/N2 addition to supercritical methanol on reactivities and fuel qualities in biodiesel production