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Reforming aqueous

Now, contrary to popular opinions, this method need not be conducted in a sealed pipe bomb. Secondary amination by substitution is as much a reaction of opportunity as it is of brute force and heat. In fact, heating can tend to cause the reformation of safrole and isosafrole. So the simplest way to do this would be to use 500mL of ammonium hydroxide or alcoholic ammonia or, for those wishing to make MDMA or meth, 40% aqueous methylamine or alcoholic methylamine (to tell you the truth, methylamine is preferable in this method because it is more reactive that ammonia so yield will increase). This 500mL is placed in a flask and into it is poured a solution of 35g bromosafrole (30g phenylisopropyl-bromide) mixed with 50mL methanol. The flask is stoppered and stirred at room temperature for anywhere from 3 to 7 days. The chemist could also reflux the same mixture for 6-12 hours or she could throw the whole mix into a sealed pipe bomb (see How to Make section) and cook it for 5 hours in a 120-130°C oil bath. [Pg.157]

Reactions. Heating an aqueous solution of malonic acid above 70°C results in its decomposition to acetic acid and carbon dioxide. Malonic acid is a useful tool for synthesizing a-unsaturated carboxyUc acids because of its abiUty to undergo decarboxylation and condensation with aldehydes or ketones at the methylene group. Cinnamic acids are formed from the reaction of malonic acid and benzaldehyde derivatives (1). If aUphatic aldehydes are used acryhc acids result (2). Similarly this facile decarboxylation combined with the condensation with an activated double bond yields a-substituted acetic acid derivatives. For example, 4-thiazohdine acetic acids (2) are readily prepared from 2,5-dihydro-l,3-thiazoles (3). A further feature of malonic acid is that it does not form an anhydride when heated with phosphorous pentoxide [1314-56-3] but rather carbon suboxide [504-64-3] [0=C=C=0], a toxic gas that reacts with water to reform malonic acid. [Pg.465]

Water-in-oil microemulsions (w/o-MEs), also known as reverse micelles, provide what appears to be a very unique and well-suited medium for solubilizing proteins, amino acids, and other biological molecules in a nonpolar medium. The medium consists of small aqueous-polar nanodroplets dispersed in an apolar bulk phase by surfactants (Fig. 1). Moreover, the droplet size is on the same order of magnitude as the encapsulated enzyme molecules. Typically, the medium is quite dynamic, with droplets spontaneously coalescing, exchanging materials, and reforming on the order of microseconds. Such small droplets yield a large amount of interfacial area. For many surfactants, the size of the dispersed aqueous nanodroplets is directly proportional to the water-surfactant mole ratio, also known as w. Several reviews have been written which provide more detailed discussion of the physical properties of microemulsions [1-3]. [Pg.472]

The ionization is reversible. The anion (acting as a weak base) can recombine with the hydrogen ion to reform neutral HA. Both reactions occur continuously in solution, with the extent of ionization dependent on the strength of the acid. Strong acids, such as HC1, ionize completely in dilute aqueous solution. Thus a 0.01 molar (10-2 molar) solution has a pH of 2. Weak acids, such as acetic and other organic acids, ionize only slightly in solution and form solutions with pH from 4 to 6. [Pg.794]

Both THP and THPP are stable in aqueous solution, as the only potential product of hydrolysis is the reformation of the hydroxymethyl groups. It is unusual for an amine-reactive functional group to have long-term stability in water or buffer, which makes these reagents uniquely suitable for creating reactive surfaces or reactive molecules for subsequent... [Pg.344]

Shabaker, J. W. Davda, R. R. Huber, G. W. Cortright, R. D. Dumesic, J. A., Aqueous-phase reforming of methanol and ethylene glycol over alumina-supported platinum catalysts. Journal of Catalysis 2003, 215, 344. [Pg.225]

Extraction of the highly acidic cobalt hydrocarbonyl by aqueous base then phase separation from product, followed by acidification to reform the hydrocarbonyl catalyst. [Pg.46]

Dumesic has reviewed the aqueous-phase reforming of polyols to H2 and CO2 under milder conditions, i.e., 200-250 °C [43], He also showed the possibility to divert the reaction towards to production of alkanes by using an acidic support for the Pt or Pd reforming catalyst. [Pg.37]


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See also in sourсe #XX -- [ Pg.44 ]




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