On the simultaneous effect of temperature, pressure, water content and space–time on acrylic acid production from propane

Discerning the Metal Doping Effect on Surface Redox and Acidic Properties in a MoVTeNbOx for Propa(e)ne Oxidation

“…Once vaporized at 150 °C, water was blended with a stream containing propane or propene, oxygen, as well as nitrogen, and the resulting mixture was then directed to the reactor. To determine the composition of the reactor effluent after commencing the reaction, periodic online analyses were carried out in an Agilent 7890A Gas Chromatograph with a configuration comprising three detectors, to wit, two flame ionization detectors (FID) and a thermal conductivity detector (TCD), two multiport valves, and four capillary columns (vide ref ( 27 ) for details).…”

“…The flow rates of gaseous species at the reactor entrance were obtained from the volumetric flow rates quantified by the MFCs. The carbon-based reactor outlet flow rate of species i was quantified indirectly via the so-called internal standard method incorporating the number of carbon atoms in the molecule as well as the atomic mass of carbon, as explained in detail in ref ( 27 ).…”

“…So far, Mo-V-based catalysts, which contain other transition metals such as Te, Nb, or Sb and are constituted of two principal crystalline phases, i.e., M1 and M2, are identified as the most successful catalysts to oxidize propane to acrylic acid. − Containing V 5+ as paraffin activating species, orthorhombic phase M1 is involved in activity and selectivity, while, lacking V 5+ species, phase M2 would improve selectivity. Although catalysts containing only phase M1 exhibit a good combined performance in propane conversion and acrylic acid selectivity, , they perform better when phases M1 and M2 operate synergistically. − Acrylic acid selectivity can be further enlarged by adjusting reaction conditions, e.g., adding water to the reaction mixture, − or by recycling unconverted propane…”

Investigating the high‐shear mixed catalytic esterification of lauric acid with methanol using central composite design

“…3 k factorial designs are suitable to estimate factors' quadratic effects but result impractical for sake of time and economy for three or more factors. 29,30 Thereby, using central composite design (CCD) is a convenient option to quantify separately factor's linear as well as quadratic effects, to identify the interaction between factors and to be able to apply the response surface methodology for prediction and optimization purposes; all this with a reasonable number of experiments. 31,32 In this work, the simultaneous influence of five key reaction variables, that is, time, mixing speed, temperature, methanol:LA ratio and catalyst mass, on the batch HSM-assisted liquid acid esterification of LA with methanol to ML is investigated.…”

“…2 k factorial designs with multiple replicates at the central point only provide information to determine main effects, two‐way interactions and overall curvature but fail to give information on the pure quadratic effect of factors. 3 k factorial designs are suitable to estimate factors' quadratic effects but result impractical for sake of time and economy for three or more factors 29,30 . Thereby, using central composite design (CCD) is a convenient option to quantify separately factor's linear as well as quadratic effects, to identify the interaction between factors and to be able to apply the response surface methodology for prediction and optimization purposes; all this with a reasonable number of experiments 31,32 .…”