Preparation, characterization and testing of newly developed titania supported VPO catalysts

Overbeek, R.A.; Warringa, P.A.; Crombag, M.J.D.; Visser, L.M.; Dillen, A.J. van; Geus, J.W.

doi:10.1016/0926-860x(95)00242-1

Cited by 57 publications

(17 citation statements)

References 12 publications

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“…These catalysts gave a significant gain in MA yield when used in a fixed-bed reactor, because of the better control of the catalyst surface temperature. Moreover, the chemical inertness of the support did not modify the reactivity properties of the precursor and of VPP, which instead is what happens with conventional supports [88]. In the case of the b-SiC-supported VPO (30 wt% of active phase), the selectivity to MA at high n-butane conversion was higher than that obtained with the unsupported catalyst.…”

Section: The Use Of Highly-heat-conducting Supportsmentioning

confidence: 89%

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

et al. 2006

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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...

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Section: The Use Of Highly-heat-conducting Supportsmentioning

confidence: 89%

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

et al. 2006

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“…Available informations on VOP-supported catalysts are rather scarce [39,40] and essentially related to their application to the oxidation of n-butane to maleic anhydride as well as to the oxidative dehydrogenation of ethane to ethylene [41][42][43][44]. The catalysts are usually prepared by impregnation of the support with an aqueous solution of VOP [34].…”

Section: Fructose Dehydration To Hmf By Different Supported Catalystsmentioning

confidence: 99%

Heterogeneous catalysts based on vanadyl phosphate for fructose dehydration to 5-hydroxymethyl-2-furaldehyde

Carlini

Patrono

Galletti

et al. 2004

Applied Catalysis A: General

162

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“…A strong interaction of the V/P/O with titania surface led to the dispersion of the former over the support, with development of an amorphous active phase, more reducible than bulk VPP. This led to a more active but less selective catalyst [11]. In our case, no apparent modification in the crystallinity of VPP occurred, but any change in active phase properties might be due to the formation of mixed V/Al/P/O solid solutions.…”

Section: The Effect Of Dilution On Catalytic Performancementioning

confidence: 60%

“…Several papers describe attempts to impregnate the active phase precursor, VO-HPO 4 AE 0.5H 2 O, on conventional supports such as titania, alumina or silica [4][5][6][7][8][9][10][11], or on less conventional ones, such as Al phosphate [12,13]. In most cases, however, the intrinsic characteristics of the VPP are worsened due to the chemical interaction, which develops between the active phase and the support.…”

Section: Introductionmentioning

confidence: 99%

The dilution of vanadyl pyrophosphate, catalyst for n-butane oxidation to maleic anhydride, with aluminum phosphate: unexpected reactivity due to the contribution of the diluting agent

et al. 2006

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This paper describes the preparation, characterization and reactivity in n-butane oxidation of catalysts made of vanadyl pyrophosphate (VPP) diluted in aluminum phosphate. Catalysts were prepared by synthesizing at the same time the VPP precursor and AlPO 4 , in order to develop mixed systems, suitable for the conglomeration into fluidizable particles by spray-drying. Al phosphate was chosen due to its presumed chemical inertness towards the active phase and towards n-butane. No evidence was obtained for the formation of mixed V/Al phosphates; an homogeneous reciprocal dispersion of the two compounds developed. However, Al phosphate showed an unexpected activity in n-butane oxidation; specifically, in the temperature range comprised between 340 and 400°C, the hydrocarbon was converted to formaldehyde and carbon monoxide by radical-like reactions. The activity of Al phosphate became negligible above 400°C, in the temperature range where instead VPP was active in hydrocarbon oxidation and selective to maleic anhydride. Moreover, Al phosphate was also responsible for the consecutive oxidative degradation of maleic anhydride, at high temperature.

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Preparation, characterization and testing of newly developed titania supported VPO catalysts

Cited by 57 publications

References 12 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?

Heterogeneous catalysts based on vanadyl phosphate for fructose dehydration to 5-hydroxymethyl-2-furaldehyde

The dilution of vanadyl pyrophosphate, catalyst for n-butane oxidation to maleic anhydride, with aluminum phosphate: unexpected reactivity due to the contribution of the diluting agent

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