Continuous heterogeneity

Figure 9 The increased complexity going from single particle in (A) to a continuous heterogeneous mixed conversion system in (I)...

This heterogeneous process may constitute an interesting alternative to the classical synthetic route. Catalyst deactivation can be slowed down by deliberately poisoning the acidic surface site with added pyridine in the reactant feed. A feasible operation mode for a continuous heterogeneous process consists of reaction and subsequent reoxidation cycles of the catalyst. 

A packed bed reactor is a continuous heterogeneous reactor. The gas or liquid phase obeys plug flow theory. The solids are considered batch, with even long-life catalyst beds losing activity over time. 

The trickle bed reactor allows for plug flow reactor assumptions even at extremely low liquid-flow rates. The trickle bed is classified as a continuous heterogeneous catalytic reactor. 

The stratum corneum is the outermost layer of the epidermis and has a thickness of 10-15 pm. It is the principal barrier for the transport of most solutes (except for very lipophilic compounds) across the skin. The stratum corneum is a continuous heterogeneous structure that consists of approximately 10-25 layers of closely packed dead keratinized cells (corneocytes) cemented together by intercellular lipids. The intercellular lipids in the stratum corneum are in the form of multiple lamellar bilayers composed mainly of ceramides, cholesterol, and fatty acids. Proteins in the stratum corneum are largely concentrated within the corneocytes as keratin fibrils. The transport of lipophilic compounds across the stratum corneum is related to the intercellular lipids (lipoidal or intercellular pathways). On the other hand, it is believed that the transport of polar and ionic compounds is related to pathways with aqueous properties (the polar or pore pathways) when the stratum corneum is under a hydrated state. ... 

For a continuous heterogeneity the expression for the overall complexation of protons with all the different site types is a multiple integral equation. A relevant more simple, but still complicated situation, is that of e.g. proton and metal ion adsorption on oxides. For such a situation and adsorption from an indifferent background electrolyte the integral proton adsorption equation is ... 

Continuous Heterogeneous Catalytic Hydrogenation of Organic Compounds in Supercritical CO2... 

Continuous heterogeneous reactors Packed-tower countercurrent reactors Fixed-bed catalytic reactors... 

Continuous heterogeneous catalysis by fixed microbial cells represents a new approach to established fermentation processes. Immobilization of isolated (and purified) enzymes and microbial cells mediating simple, monoenzyme reactions has already been reduced to industrial practice. However, the development of immobilized cell systems to carry out complex fermentation processes—characterized by multiple reactions cind complete reaction pathways involving coenzymes—is still in its infancy. Drawing upon our rather concerted effort in this area over the past several years, we are appraising the prospects and problems of such a technological advancement in this brief communication. 

Gas phase reactors Gaseous monomers, continuous heterogeneous solid cat. PE, PP fluidized beds horizontal with weirs rotating paddles helically stirred tanks. 

The application of microflow-through devices is of particular interest for continuous heterogeneous catalysis with nanoparticles. The advantages of nanoparticles are their special surface properties on the one hand and the high specific surface area on the other. 

Bersillon, J. -L., F. Villieras, F. Bardot, T. Corner, and J. -M. Cases. 2001. Use of the Gaussian distribution function as a tool to estimate continuous heterogeneity in adsorbing systems. Journal of Colloid and Interface Science 240, no. 2 400-411. doi 10.1006/ jcis.2001.7657. 

Here we generalize the harmonic rule for discrete cores having distinctly different rock properties, to single lineal cores having continuous heterogeneous properties. This is accomplished by considering... 

Examples like gibbsite are not the rule (i.e., in most cases, a single-site model does not correspond to what is actually expected). Therefore, a combination of Eqs. (9) and (10) is, in principle, required to account for the different distinct sites and their potential individual continuous heterogeneity. This results in... 

Another report of hydrogenation under SCF conditions from the patent literature includes claims for a continuous heterogeneously catalyzed hydrogenation reaction process by Subramaniam and Said (182,183). The primary focus of these patents is the in situ mitigation of coke buildup in porous catalysts, but an SCF-mediated hydrogenation process is a cited application (and claim). 

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