Conversion processes integration

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. 

For the total integrated biomass production—conversion system, the arithmetic product of the efficiencies of biomass production and conversion is the efficiency of the overall system. An overall conversion efficiency near 45% would thus be produced by integrating the biomass plantation illustrated in Table 30 with a conversion process that operated at an overall efficiency of 50%. Every operation in the series is thus equally important. 

Fluid catalytic cracking (FCC) continues to play a key role in an integrated refinery as the primary conversion process. For many refiners, the cat cracker is the key to profitability in that the successful operation of the unit determines whether or not the refiner can remain competitive in today s market. 

If the PBR is less than unity, the oxide will be non-protective and oxidation will follow a linear rate law, governed by surface reaction kinetics. However, if the PBR is greater than unity, then a protective oxide scale may form and oxidation will follow a reaction rate law governed by the speed of transport of metal or environmental species through the scale. Then the degree of conversion of metal to oxide will be dependent upon the time for which the reaction is allowed to proceed. For a diffusion-controlled process, integration of Pick s First Law of Diffusion with respect to time yields the classic Tammann relationship commonly referred to as the Parabolic Rate Law ... 

The other master data elements for which an integration process is required are recipes. Recipes used within the PP/DS module are tightly integrated with the recipes in the ERP system. For complexity reduction in master planning, as outlined in the SNP section above, simplified recipes are used in SNP. These are derived from the PP/DS recipes by a flexible, automated conversion process. 

Full exploitation of cascade conversions by the true integration of biocatalytic and chemocatalytic procedures requires merging human s chemistry with nature s reaction conditions the latter impose a much stricter constraint with respect to reaction temperature, pressure and medium (Fig. 13.16). Consequently, a renaissance in the field of synthetic organic chemistry and catalysis is necessary to develop novel conversion processes that meet biocatalytic conditions. 

A biorefinery is a facility that integrates biomass conversion processes and eqtrip-ment to produce fuels, power, and value-added chemicals from biomass. Biorefinery is the co-production of a spectram of bio-based products and energy from biomass. The biorefinery concept is analogous to today s crude oil refinery. Biorefinery is a relatively new term referring to the conversion of biomass feedstock into a host of valuable chemicals and energy with minimal waste and emissions. 

Like all other retroviruses, human immunodeficiency virus type 1 (HIV-1) contains the multifunctional enzyme reverse transcriptase (RT). Retroviral RTs have a DNA polymerase activity that can use either an RNA or a DNA template and an RNase H activity. HIV-1 RT is essential for the conversion of single-stranded viral RNA into a linear double-stranded DNA that is subsequently integrated into the host cell chromosomes [1-4]. In this conversion process HIV-1 RT catalyzes the incorporation of approximately... 

Recently, the CO-EXtraction (COEX) process was proposed by AREVA-France (104). The COEX process initially coextracts all of the U and Pu, and subsequently splits them into a U stream and a Pu stream containing an equal amount of U. In addition, a hydrometallurgical co-conversion process is coinstalled in an integrated recycling plant, which produces homogenous mixed actinide oxides (105, 106). Thus, the PR is enhanced. 

In some cases, a replacement system will be installed which can access the data records from the previous system, including historical data, to enable such data to be available in the format used by the new system. If necessary, a data conversion process must be carried out. Where system obsolescence forces the need to convert electronic records from one system or format to another, the conversion process must be qualified and its integrity verified. The electronic copies of electronic record files can be considered to be electronic record files provided that the data transfer processes have been verified. Services such as Digital Notary expedite the verification of the conversion process. 

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