Acrylic acid Catalytic reactors

The surface transformations of propylene, allyl alcohol and acrylic acid in the presence or absence of NHs over V-antimonate catalysts were studied by IR spectroscopy. The results show the existence of various possible pathways of surface transformation in the mechanism of propane ammoxidation, depending on the reaction condition and the surface coverage with chemisorbed NH3. A surface reaction network is proposed and used to explain the catalytic behavior observed in flow reactor conditions. 

Alternatively, acrylic acid can be obtained in a two-step reactor in which glycerol is catalytically dehydrated with an acid catalyst like H3PO4 on a-alumina [67]. The obtained acrolein is then oxidized with a commercially available oxidation catalyst, viz. Mo/V/W/Cu-oxide on a-alumina, yielding up 55% polymerization grade acrylic acid (Scheme 11.8) [68]. 

Option 3 (Figure 1) which contains all basic and additional processing units can be described as follows. Acrylic acid is produced by partial oxidation of propylene in a fluidized-bed catalytic reactor. To prevent any side reaction, a cold recycle quench is used immediately after reactor. Deionized water in the off-gas absorber absorbs off-gas from the quench tower, containing acetic acid, acrylic acid, unreacted propylene, and byproducts. In the next step, an acid extractor is used for liquid-liquid extraction to... 

Ethylene and synthesis gas are used to produce propionaldehyde and formaldehyde. These aldehydes then are reacted in the presence of a catalyst to form methacrolein. The methacrolein reacts with atmospheric oxygen to form meth-acrylic acid in a catalytic multitubular reactor. The methacrylic acid is separated from water (a byproduct) and purified it then reacts with methanol to form MMA. The byproducts are incinerated on-site to recover the energy in the process [41]. 

A multi-bed catalytic reactor is also claimed for the production of acrylic acid in which propene, glycerol and air are co-fed to the reactor. The first bed serves for the dehydration of glycerol to acrolein, the second bed for the oxidation of propene to acrolein, and the third bed for the oxidation of acrolein to acrylic acid [108c, e]. 

On the other hand, it can be mentioned as a curious novelty that an electrochemical membrane reactor using Bi4Cuo.2Vi.sOn- as a solid electrolyte membrane has been recently reported to enhance the catalytic behavior of a MoVo.3Teo.17Nbo.12Oj catalyst with respect to the use of a conventional fixed-bed reactor, achieving 42% propane conversion with selectivity to acrylic acid of 80% at 380°C. ... 

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