Biomass development, survey

Human activity, particularly in the developing world, continues to make it more difficult to sustain the world s biomass growth areas. It has been estimated that tropical forests are disappearing at a rate of tens of thousands of hm per year. Satellite imaging and field surveys show that Brazil alone has a deforestation rate of approximately 8 x 10 hm /yr (5). At a mean net carbon yield for tropical rain forests of 9.90 t/hm yr (4) (4.42 short ton /acreyr), this rate of deforestation corresponds to a loss of 79.2 x 10 t/yr of net biomass carbon productivity. 

This chapter surveys different process options to convert terpenes, plant oils, carbohydrates and lignocellulosic materials into valuable chemicals and polymers. Three different strategies of conversion processes integrated in a biorefinery scheme are proposed from biomass to bioproducts via degraded molecules , from platform molecules to bioproducts , and from biomass to bioproducts via new synthesis routes . Selected examples representative of the three options are given. Attention is focused on conversions based on one-pot reactions involving one or several catalytic steps that could be used to replace conventional synthetic routes developed for hydrocarbons. 

Ouwens, C.D., Boerrigter, H., (2001) New developments in the field of tri-generation from biomass waste A survey. In these proceedings. 

Hydrothermal liquefaction is a process for the conversion of biomass into an organic product oil. It has been widely studied in the early 1980 s (see the recent extensive literature survey in [1]), Starting in 1983 Shell Research performed process development based on experiments in autoclaves and a continuous bench scale unit. This resulted in a conceptual design for the HTU process including cost estimate [2,3]. The work was discontinued in 1988. 

For all of these reasons, there has been a rapid intensification of efforts in recent years to develop processes that will allow us to utilise a variety of plant materials, biomass, as a source of chemicals and liquid fuels. Ionic liquids have been widely investigated as solvents for these processes because of some of the unique properties that they possess. The goal of this overview therefore, is to survey and discuss recent developments in the use of ionic liquids in this extremely important field of biomass processing. 

We can only speculate on the true size of the total timber resource of the United States. To date, all of the inventories and surveys on a national scale have been based on volume measurements of the merchantable parts of trees. Tables I, II, and III reflect this. Merchantable volume is a vague term, particularly since merchantability limits are rapidly changing. The concept of whole-tree utilization has reinforced this confusion. With the development of whole-tree harvesting methods, previously non-merchantable parts of the tree are chipped and used for pulp and paper, composite products, and fuel. These new concepts of utilization make the whole tree the basic unit of measurement. Since accurate volume determination is difficult on irregular shaped objects, weight of biomass is the new standard of measure for all tree components. 

There have been numerous estimates made on the total biomass and biomass potential of our forests 3,1Q). The inventory procedure used is based on estimates and averages, and is fully described by Wahlgren and Ellis (U). Forest surveys based on biomass measurement techniques are needed to accurately determine the quantities and location of our wood resource. Many studies on measuring the weight of individual trees, and to a lesser extent forest stands, have been made. This work has been summarized by Keays (12). and Hitchcock and McDonnell (12)- As work in forest biomass measurement is refined, regional weight tables can be developed and accurate biomass inventories compiled. 

The first part of this chapter is intended to survey recent literature on new catalytic materials because the development of new types of metal oxides and layered- and carbon-based materials with different morphologies opens up novel acid-base catalysis that enables new type of clean reaction technologies. Mechanistic considerations of acid- and base-catalyzed reactions should result in new clean catalytic processes for Green and Sustainable Chemistry, for example, transformations of biorenewable feedstock into value-added chemicals and fuels [21-35]. The latter part of this chapter, therefore, focuses on biomass conversion using solid acid and base catalysts, which covers recent developments on acid-base, one-pot reaction systems for carbon-carbon bond formations, and biomass conversion including synthesis of furfurals from sugars, biodiesel production, and glycerol utilization. 

The advent of easy access to the satellite-based global positioning system (GPS) and availability of off-the-shelf portable probes and rapid analyzers for a number of water quality determinants have enabled the development of systems that can be carried on small survey vessels to map water quality conditions. Rapid data acquisition is now practical using probes and sondes for measuring temperature, conductivity, turbidity, pH, and dissolved oxygen fluorometric technologies for chlorophyll biomass and phytoplankton composition flow injection and loop flow analysis for some nutrient species and acoustic Doppler-based devices for current profiling. 

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