The science of catalytic reaction engineering studies the catalyst and the catalytic process in the laboratory in order to predict how they will perform in production-scale reactors. Surprises are to be avoided in the scaleup of industrial processes. The laboratory results must account for flow, heat and mass transfer influences on reaction rate to be useful for scaleup. Calculated performance based on these results must also be useful to maximization of profit and safety and minimization of pollution.
The realm of aqueous organometallic catalysis incorporates many more reactions and catalysts than discussed in the preceeding chapters. However, these were not investigated in so much detail as, for instance, hydrogenation or hydroformylation; some of them are mentioned only here and there. An attempt is made to give a representative sample of these studies.
Problem 1.1a: For a reaction AB (rate expression: rA = kCA ) , taking place in an isothermal tubular
reactor, starting with the mass balance equation and assuming plug flow, derive an expression for calculating
the reactor volume in terms of the molar flow rate of reactant ‘A’.
Chemical reaction engineering (reaction engineering or reactor engineering) is a specialty in chemical engineering or industrial chemistry dealing with chemical reactors. Frequently the term relates specifically to catalytic reaction systems where either a homogeneous or heterogeneous catalyst is present in the reactor.
Chemical reaction engineering is concerned with the exploitation of chemical reactions on a commercial scale. It's goal is the successful design and operation of chemical reactors. This text emphasizes qualitative arguments, simple design methods, graphical procedures, and frequent comparison of capabilities of the major reactor types. Simple ideas are treated first, and are then extended to the more complex.
This book is an introduction to the quantitative treatment of chemical reaction engineering.
The level of the presentation is what we consider appropriate for a
one-semester course. The text provides a balanced approach to the understanding
of: (1) both homogeneous and heterogeneous reacting systems and (2) both chemical
reaction engineering and chemical reactor engineering. We have emulated the teachings
of Prof. Michel Boudart in numerous sections of this text.
Polymers present a class of materials that play a role of importance growing in catalysis. Polymeric catalysts based on polypropylene-polyacrylic acid (PP-APA) were prepared by the two methods: co-polymerization in the presence of transition metal ions (Cu(II), Fe(III), Co(II), Mn(II)…) and soaking method. Their catalytic activity was determined by oxidation reactions of ions S2- and hydroquinone by molecular oxygen in normal condition.
Catalytic oxidation of organic compounds is an extremely important field of chemistry, spanning the range from biological oxidations to large scale industrial production of commodity chemicals. However, many of these transformations can hardly be classified as organometallic reactions, since the catalysts (often simple metal salts) and the intermediates can be rather regarded as coordination complexes than organometallic compounds.
Most glucoamylases (a-1,4-d-glucan glucohydrolase, EC 126.96.36.199) have
structures consisting of both a catalytic and a starch binding domain. The
structure of a glucoamylase from Saccharomycopsis fibuligeraHUT 7212
(Glu), determined a few years ago, consists of a single catalytic domain.
The structure of this enzyme with the resolution extended to 1.1 A˚
of the enzyme–acarbose complex at 1.6 A˚
resolution are presented here.
We seek to design reaction vessels, i.e. chemical reactors, where a particular chemical reaction (or set of
reactions) is carried out. The first decision we take involves the configuration of the reactor and its mode of
operation. This means we must decide what reactor type (and reactor shape) to select and whether it would be
advantageous to operate in batch or continuous mode.
In this work, platinum nanoparticles were dispersed on SBA-15 mesoporous material by incipient wetness method and the synthesized materials were characterized by XRD, TEM, EDX spectroscopies and N2 adsorption-desorption isotherm measurement. The results indicated that 2D hexagonal ordered structure of SBA-15 was still maintained after grafting Pt on SBA-15 support and platinum nanoparticles existed both inside and outside the pore channels of SBA-15 material. Catalytic activity of these materials was tested in the aqueous phase D-glucose oxidation as a model reaction. ...
l-Rhamnose isomerase (l-RhI) catalyzes the reversible isomerization of
l-rhamnose to l-rhamnulose. Pseudomonas stutzeril-RhI, with a broad
substrate specificity, can catalyze not only the isomerization ofl-rhamnose,
but also that betweend-allose andd-psicose. For the aldose–ketose isomer-ization by l-RhI, a metal-mediated hydride-shift mechanism has been
proposed, but the catalytic mechanism is still not entirely understood.
The alternative fuels that are derived from non-fossil source are very promising fuels for the future. Catalytic cracking of vegetable oil sludge is an advanced method for obtaining of bio- fuels. The huge waste in the vegetable oil manufacture could be converted to bio-fuel. Cracking of vegetable oil sludge by HY catalyst using MAT5000 instrument is a precious method for studying this catalytic cracking reaction. By catalytic cracking, the LPG gas, gasoline product, LCO and HCO products are also formed of vegetable oil sludge.
Lecture Organic chemistry - Chapter 12: Reactions of alkenes. In this chapter, the following content will be discussed: Addition reactions of alkenes, catalytic hydrogenation, electrophilic additions, hydroboration-oxidation,...and other contents.
The hyperthermostable chitinase from the hyperthermophilic archaeon
Pyrococcus furiosushas a unique multidomain structure containing two chi-tin-binding domains and two catalytic domains, and exhibits strong crystal-line chitin hydrolyzing activity at high temperature.
Group I introns catalyze the self-splicing reaction, and their derived ribo-zymes are frequently used as model systems for the study of RNA folding
and catalysis, as well as for the development of non-native catalytic
The cold-active protein tyrosine phosphatase found in psychrophilicShewa-nellaspecies exhibits high catalytic efficiency at low temperatures as well as
low thermostability, both of which are characteristics shared by many cold-active enzymes.
The catalytic reaction mechanism and binding of substrates was investi-gated for the multisubstrateDrosophila melanogasterdeoxyribonucleoside
kinase. Mutation of E52 to D, Q and H plus mutations of R105 to K and
H were performed to investigate the proposed catalytic reaction mech-anism, in which E52 acts as an initiating base and R105 is thought to sta-bilize the transition state of the reaction.
The catalytic mechanism underlying the aminopeptidase fromStreptomyces
griseus (SGAP) was investigated. pH-dependent activity profiles revealed
the enthalpy of ionization for the hydrolysis of leucine-para-nitroanilide by
SGAP. The value obtained (30 ± 5 kJÆmol
) is typical of a zinc-bound
water molecule, suggesting that the zinc-bound water⁄hydroxide molecule
acts as the reaction nucleophile.