Effect of Ce–Fe oxides additives on performance of VPO catalyst for n-butane oxidation to maleic anhydride in the absence of gas-phase oxygen

Shen, Shubao; Jiping, Zhou; Zhang, Fengsheng; Zhou, Ling; Li, Ranjia

doi:10.1016/s0920-5861(01)00528-4

Cited by 22 publications

(10 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Therefore it seems that the size of the molecule plays a role in determining the maximum amount of glycol which can be trapped in the interlayer spacing of the precursor, in agreement with literature data obtained using other types of alcohols [54,72]. The Improvement of redox properties [47] Fe, Fe/V 0.08 Increase of catalytic activity Fe replaces V 4+ in (VO) 2 P 2 O 7 . The re-oxidation rate is increased [48,49] Ga, Ga/V 0.10 C 22 fi 73% and S 55 fi 51% Increase of surface area + increase of intrinsic activity (electronic effect) [50] Nb, 0.25 wt% C 20 fi 17% and S 35 fi 53% Increase of surface acidity promotes desorption of MA [44] Nb, Nb/V 0.01 C 58 fi 75% and S 70 fi 70% Nb concentrates at the surface, where defects are generated.…”

Section: Other Options For Modifications Of Vpp Chemical-physical Prosupporting

confidence: 85%

VPO catalyst for n-butane oxidation to maleic anhydride: A goal achieved, or a still open challenge?

et al. 2006

View full text Add to dashboard Cite

A Partner of Concorde CA and of Idecat NoE, 6FP of the EU) b Lonza SpA, via E. Fermi 51, 24020 Scanzorosciate (BG), ItalyThis review describes recent findings in the oxidation of n-butane to maleic anhydride. The process is commercial since the 80's, but yet the yield is far from being optimised. Therefore, it represents an emblematic example of how several scientific disciplines, from solid-state science to reactor technology, can contribute to the improvement of the process performance.KEY WORDS: Vanadyl pyrophosphate; n-butane; selective oxidation; maleic anhydride 1. The oxidation of n-butane catalysed by VPO: How to improve process performance?The activation of light alkanes by high-temperature contact with a redox catalyst represents one way to transform these hydrocarbons to valuable chemicals (a few reviews and books dealing with this topic, published after 1998, are refs [1-18]). The most successful example is the oxidation of n-butane to maleic anhydride (MA), catalysed by a V/P/O-based catalyst (VPO), which starting from the 80's has been replacing in part the commercial synthesis from benzene. This reaction, and the unique chemical-physical properties of the vanadyl pyrophosphate (VO) 2 P 2 O 7 (VPP), the active and selective phase for this reaction, are amongst the most studied topics in catalysis during the latest decades, initially with the aim of understanding which catalyst peculiarities make this complex transformation possible, and later on with the aim of improving the process performance.MA finds its major use in the production of unsaturated polyesters and of butanediol. The yearly world consumption exceeds 1.3 · 10 6 metric tons [19]. Approximately 70% is produced by n-butane oxidation, the remaining still being obtained from benzene. There are several reactor technologies available, including fixed-bed (Scientific Design, Huntsman, BASF, Pantochim), fluidised-bed (Lonza, BP, Mitsubishi), and transported-bed (DuPont). Best process performances reported in patent literature range from 53 to 65% molar yield to MA [20][21][22][23][24][25], with a conversion of the hydrocarbon not higher than 85-86%. An excellent result of more than 70% yield is reported [26], which however refers to a recycle process. In lab reactors best yields reported are lower than 50%.The best performance for a fixed-bed reactor does not exceed 65% per-pass yield, while that in a fluidised-bed is typically somewhat lower; in fact, back-mixing phenomena are responsible for the consecutive combustion of MA. Moreover, with fluidised-bed operation n-butane-richer conditions can be used (up to 5 molar % in feed); under the latter conditions, a worsening of selectivity is expected, which however is compensated by a considerable improvement in MA productivity. In the fluidised-bed process developed by Lonza and Lummus (shown in figure 1), the loss of selectivity is also compensated by the higher amount of high-pressure steam produced, due to the more efficient removal of the reaction heat and to the more CO x produced.The maximu...

show abstract

Section: Other Options For Modifications Of Vpp Chemical-physical Prosupporting

confidence: 85%

VPO catalyst for n-butane oxidation to maleic anhydride: A goal achieved, or a still open challenge?

et al. 2006

View full text Add to dashboard Cite

show abstract

“…is negligible in this system. According to previous reports [23][24][25][26], reduction of V 5? and V 4?…”

Section: H 2 -Tpr Studiesmentioning

confidence: 72%

Partial Oxidation of Isobutane over Vanadium Phosphorus Oxides

Guan

Wang

et al. 2008

Catal Lett

View full text Add to dashboard Cite

A series of vanadium phosphorus oxides (VPO) were prepared by using dodecyl amine as surfactant and tested for the partial oxidation of isobutane and isobutene. Characterization results showed that their structure and properties depend on the content of dodecyl amine. Catalytic tests showed that relatively high isobutane conversion and desired product selectivity can be achieved over a proper dodecyl amine doping VPO catalyst. It is also found that higher isobutane conversion can be achieved over V 4? -containing phases as compared to V 5? -containing phases, while proper surface V 5? /V 4? ratio may be propitious to obtain high selectivity to methacrylic acid for the selective oxidation of isobutane. In addition, the content of dodecyl amine in the preparation of the VPO catalysts appears to be more important in determining the surface P/V ratio of the catalysts.

show abstract

“…These catalysts gave only the characteristic reflections of (VO) 2 P 2 O 7 with peaks observed at 2θ = 22.9º, 28.5ºand 30.0º which are corresponding to the reflection of (020), (024) and (221) planes, respectively. It is general believed that (VO) 2 P 2 O 7 is the active phase of VPO catalysts and the active crystal plane for selective oxidation of n-butane is the (020) plane 11 . Interestingly, the catalysts synthesized via VPD method shows higher crystalline structure as the calcinations duration increased.…”

Section: X-ray Diffraction (Xrd)mentioning

confidence: 99%

Effect of Different Calcination Duration on Physicochemical Properties of Vanadium Phosphate Catalysts

Taufiq‐Yap

Lee²,

Wong³

et al. 2012

Journal of Chemistry

View full text Add to dashboard Cite

Vanadium phosphate catalysts have been prepared by calcining VOHPO44·0.5H2O which were prepared via two methods i.e. organic (VPO method) and dihydrate (VPD method) routes for different duration under anaerobic atmosphere. Increasing the calcinations duration led to a decrease in total surface area. It is also promote the formation of V5+phase in the catalysts. Scanning electron microscopy clearly revealed that the morphologies of all catalysts composed of plate-like crystallites that were arranged into the characteristic of rosette cluster. However, by increasing the pretreatment duration in an inert environment, the rosette-shape of the clusters which normally obtained in reaction condition was collapsed. Prolong the duration of N2calcination also resulted in an increment in the amount of oxygen desorbed (from O2-TPD) and removed (obtained from H2-TPR).

show abstract

Effect of Ce–Fe oxides additives on performance of VPO catalyst for n-butane oxidation to maleic anhydride in the absence of gas-phase oxygen

Cited by 22 publications

References 13 publications

VPO catalyst for n-butane oxidation to maleic anhydride: A goal achieved, or a still open challenge?

VPO catalyst for n-butane oxidation to maleic anhydride: A goal achieved, or a still open challenge?

Partial Oxidation of Isobutane over Vanadium Phosphorus Oxides

Effect of Different Calcination Duration on Physicochemical Properties of Vanadium Phosphate Catalysts

Contact Info

Product

Resources

About