Renewable resources approaches

Kaplan DL (ed) (1998) Biopolymers from Renewable Resources Macromolecular Systems-Materials Approach. Springer, Berlin Heidelberg New York... 

The Non-renewable Resource Assessments (NRAs) are part of step 5 in an 8-step process that may ultimately result in (partial or limited) protection of certain areas from development. Phase 1 of an NRA is a desktop exercise that evaluates all existing mineral deposit and survey data for an area from all sources, determines knowledge gaps of the mineral potential, and suggests an approach for Phase 2 follow-up work. Phase 2 of the NRA typically involves field and analytical work designed to lead to a better understanding of the resource potential for a candidate protected area. 

Until recently, synthesis of nanostructured carbon materials was usually based on very harsh conditions such as electric arc discharge techniques [1], chemical vapor deposition [2], or catalytic pyrolysis of organic compounds [3]. In addition (excluding activated carbons), only little research has been done to synthesize and recognize the structure of carbon materials based on natural resources. This is somewhat hard to understand, as carbon structure synthesis has been practiced from the beginning of civilization on the base of biomass, with the petrochemical age only being a late deviation. A refined approach towards advanced carbon synthesis based on renewable resources would be significant, as the final products provide an important perspective for modern material systems and devices. 

Being convinced of the value of the renewables approach for the industrial world, as well as for developing countries, I was myself delighted to collaborate on this series of books focusing on different aspects of renewable resources. I hope that readers become aware of the complexity, the interaction and interconnections, and the challenges of this field and that they will help to communicate on the importance of renewable resources. 

Recently, we reported that the rhodium/BIPHEPHOS-catalyzed hydroformylation of trans-4-octene (Scheme 6) provides an interesting approach for the synthesis of n-nonanal [23]. In this context trans-4-octene can also be seen as a model substance for hydroformylation of internally unsaturated fatty acid esters. This could open up access to the use of renewable resources for the synthesis of valuable n-aldehydes. 

There are several examples of dehydrations of chemicals derived by renewable resources by use of heteregeneous catalytic approaches in the literature. These can be categorized into three types of reactions (a) reactions in which one (or more) molecule(s) of water is eliminated from a single substrate molecule, (b) reactions in which one (or more) molecule(s) of water is generated as the result of an esterification reaction between an alcohol and a carboxylic acid or carboxylic acid derivative and (c) reactions in which one (or more) molecule(s) of water is generated due to an etherification reaction between two alcohol functionalities. 

One approach to addressing the measurement of the use of renewable resources would be to develop mass metrics that record the amount or proportion of renewable resources used in a process, for example, a renewables intensity analogous to mass intensity. 

While this reaction is substantially exothermic (6), it provides an intriguing approach to the production of fuels from renewable resources, as the required acids (including acetic acid, butyric acid, and a variety of other simple aliphatic carboxylic acids) can be produced in abundant yields by the enzymatic fermentation of simple sugars which are, in turn, available from the microbiological hydrolysis of cellulosic biomass materials ( ] ) These considerations have led us to suggest the concept of a "tandem" photoelectrolysis system, in which a solar photoelectrolysis device for the production of fuels via the photo-Kolbe reaction might derive its acid-rich aqueous feedstock from a biomass conversion plant for the hydrolysis and fermentation of crop wastes or other cellulosic materials (4). 

Cellulose is the most abundant renewable resource available for con- version to fuel, food, and chemical feedstocks. It has been estimated by Ghose (11) that the annual worldwide production of cellulose through photosynthesis may approach 100 X 109 metric tons. As much as 25% of this could be made readily available for the conversion processes. A significant fraction of the available cellulose, i.e., 4-5 X 109 t/year, occurs as waste, principally as agricultural and municipal wastes. Cellulose must be viewed, therefore, as an important future source of fuel, food and chemicals (see Table I). 

On the other hand, some renewable resources like PV systems remain costly when compared to traditional energy. Flowever, the cost gap is expected to continue to decrease, and, to the extent deployment is accelerated, the gap should close even faster taking into account new approaches as for instance PV/thermal combined systems. Other renewable resources, such as biomass, small hydro, and wind can successfully compete with traditional resources. This is especially true if value (or cost) is assigned to the security attributes. 

A major aspect of research and development in industrial catalysis is the identification of catalytic materials and reaction conditions that lead to effective catalytic processes. The need for efficient approaches to facilitate the discovery of new solid catalysts is particularly timely in view of the growing need to expand the applications of catalytic technologies beyond the current chemical and petrochemical industries. For example, new catalysts are needed for environmental applications such as treatment of noxious emissions or for pollution prevention. Improved catalysts are needed for new fuel cell applications. The production of high-value specialty chemicals requires the development of new catalytic materials. Furthermore, new catalysts may be combined with biochemical processes for the production of chemicals from renewable resources. The catalysts required for these new applications may be different from those in current use in the chemical and petrochemical industries. 

Recent attempts aim at the controlled transformation of cellulose, hemicellulose, and lignin to platform molecules for a potential future biorefinery scenario. In this regard, the U.S. Department of Energy has published studies on potential future platform molecules that could be derived from renewable resources [35, 36]. Tailored transformation of biomass to these platform chemicals could serve as a starting point for biofuel production. This would allow the development of comprehensive biorefinery approaches that incorporate both the production of biofuels and chemicals. The... 

Encouraging results on the bonding of plastics to wood using tailor-made cellulose-polystyrene graft polymers as compatibilizers or interfacial agents may offer a new approach to the engineering of wood-plastic products with improved mechanical and physical properties for a variety of applications. It also holds the potential of opening up new markets for renewable resources in the form of woody materials. For example, polystyrene production is currently 3.9 billion... 

An additional approach to environmentally responsible inks is to source the raw materials from renewable resources. In this approach solvents are based mainly on alkyl lactates and binders such as cellulose or nitrocellulose. ... 

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