Catalytic conversion of c3 aliphatics to higher hydrocarbons

Catalytic conversion of C8 aliphatics to higher hydrocarbons

This invention relates to a catalytic process for butanes and C5 aliphatic⁺for the production of hydrocarbons from propane. In particular, it relates to a technique for improving the reaction rate of a propane feedstock for the catalytic conversion of a feedstock to an acidic medium pore size above a zeolite.

Propane, a naturally occurring material and a by-product of many petroleum refining processes, has little economic value and is often burned as a fuel gas or used as a component in liquefied petroleum gas (LPG). Efforts have been made to convert propane to more valuable hydrocarbons such as butanes, higher aliphatics, isoalkanes and aromatics. The isobutane product is a valuable material in the alkylation of lower molecular weight olefins to hydrocarbons in the boiling range of gasoline. The aromatic product and normal butane can be blended with gasoline to increase the octane number or used as a petrochemical feedstock.

Numerous methods and process conditions for refining a propane feedstock have been proposed in the art in the past. Many of these methods provide a mixture of propane and olefin as a feedstock for the catalytic conversion process.

U.S. Patent No. 3,775,501 (Kaeding, et al.) Discloses a process for improving the yield of aromatics from a hydrocarbon such as propane (claim 21) using a crystalline aluminosilicate zeolite catalyst. There is no indication that a mixed feed of propane and olefin would be used. The reaction is carried out at a temperature of about 260-270 ° C.

U.S. Patent No. 3,845,150 (Yan et al.) Discloses a process for preparing aromatic hydrocarbons above a ZSM-5 type catalyst from a mixed feed containing n.

20-65% by weight of saturated hydrocarbons and about 20-50% by weight of olefins. Saturated hydrocarbons may consist of C3 hydrocarbons and olefins may consist of propylene. The mixed feed makes it possible to carry out the process under substantially heat-balanced conditions. It does not reveal any increased reactivity of the saturated hydrocarbon portion of the feed due to the presence of added olefin. Likewise, the liquid product obtained from the process contains substantially insignificant amounts of butanes and almost entirely aromatics (e.g. 90% aromatics in Example II).

U.S. Patent No. 3,960,978 (Givens et al.) Discloses a process for preparing a liquid hydrocarbon product consisting primarily of higher olefins and up to about 20% by weight of aromatics using 20 C 1 -C 5 paraffins and C 2 -C 5 a mixed feed of olefins and a ZSM5-type catalyst having an alpha value of about 0.1-120. The yield of butanes in the process is negligible.

It has now been found that when a controlled amount of monoolefin is mixed with propane, it is efficiently converted with an unexpectedly high selectivity to a mixture rich in normal butane, isobutane, pentanes and Cg⁺aliphatics when contacted with certain medium pore size zeolites 30 under a specified set of operating conditions. In particular, this invention relates to method C4⁺to produce hydrocarbons from a mixture of propane with an amount of lower molecular weight monoolefin sufficient to increase the reaction rate of propane. In a preferred process, preferably, without added hydrogen and above n. 3400 at a pressure of kPa, a feed consisting essentially of propane and a monoolefin, in contact with a catalyst consisting of a crystalline aluminosilicate alloy having a silica to alumina ratio of at least 12 and a control index of 1-12, which process is carried out at a temperature, pressure and volume flow rate of effective to convert at least 10% of propane to a mixture of hydrocarbons containing butanes in an amount corresponding to at least wt% of the converted propane.

The total effluent from the catalytic reactor contains unreacted propane, which can be separated and recycled to the solid bed reaction zone in an amount sufficient to maintain about 60-90% propane in the mixed feed assembly. The effluent separation step results in a heavier hydrocarbon product containing aliphatic C4⁺hydrocarbons from which isobutanes can be obtained, which is useful for conversion into an alkylate blending feedstock for gasoline. Normal butanes are also obtained for gasoline blending. Only a small amount of C1-C2 hydrocarbons are formed.

In fact, the process of the present invention provides a petroleum refiner with a process for converting a propane by-product of low economic value, often burned as a fuel, to a much more valuable high octane alkylate blended with gasoline. The method of the present invention is advantageous because it requires a very simple process structure.

Propane can be continuously fed to the reactor mixed with a controlled amount of C 2 -C 15 monoolefin, preferably a C 2 C 4 olefin such as propylene. The catalyst layer may be a simple solid layer, although a fluidized bed may be used. The life of the cycle has been shown to be long, so frequent catalyst regeneration is not required.

In the drawings, Figure 1 is a comparison between a pure propane feed and a mixed feed of propane (90 wt%) and propylene (10 wt%) in the propane conversion reaction.

Figure 2 is a graphical representation of the effect of temperature on propane conversion using the mixed feed of Figure 1.

Figure 3 is a graphical representation of product selectivity as a function of reaction temperature using the mixed feed of Figure 1.

Figure 4 is a graphical representation of the amount of converted propane as a function of reaction temperature when using a 20/80 C3 / C3 · mixed feed.

Figure 5 is a graphical representation of both the predicted equilibrium conversions and the experimental results with a propane / propylene15 mixed feed.

Figure 6 is a graphical representation of the absolute amount of converted propane (in percent) as a function of conversion reaction temperature at four different propane / propylene mixed feeds.

This invention relates to an improved process for converting an aliphatic C3 hydrocarbon feed to predominantly aliphatic C4⁺to produce hydrocarbons by contacting a C3 feed containing propane and about 10-40% by weight of a monoolefin with an acidic, shape-selective, medium pore size zeolite catalyst having a control index of 1-12 at about 200-400 ° C. at a temperature of more than about 3400 kPa under reaction conditions to convert at least 10% of the amount of propane, and recovering a product rich in 30 aliphatic C4⁺hydrocarbons such as butane, isobutane and pentane and up to 10% by weight of methane and ethane in total. Metric units and parts by weight are used in this specification unless otherwise indicated.

The feed to the process of this invention consists essentially of a hydrocarbon mixture with a certain amount of propane. Suitable sources of propane feed include petroleum refining streams, such as the C3 fraction from catalytic fluidized bed (FCC) exhaust gas, and wet natural gas.

The monoolefin co-feed contains one or more unsaturated C2-C18 hydrocarbons. In a preferred embodiment, the monoolefin is a C2-C4 hydrocarbon and most preferably propylene. The location of ethylenic unsaturation in the aliphatic molecule may be in the middle or at the ends. Under the reaction conditions, the C2-C15 olefins are converted to each other to give a corresponding series of unsaturated hydrocarbons.

It has been found that the beneficial effects of olefin addition to the propane feedstock are optimized over a range of operating conditions. In a preferred embodiment, the mixed feed contains about 80 wt% propane and 20 wt% propylene at a temperature of about 285-370 ° C and a pressure above about 2020 kPa. Although it is preferred to exclude the added hydrogen from the reaction, inert diluents such as nitrogen may be mixed into the feed.

The preferred process minimizes the formation of methane and ethane. In a typical solid bed reaction under elevated temperature and pressure conversion conditions, a mixed feed containing n. 60-90% by weight of propane and a lower molecular weight monoolefin or olefin precursor, is contacted with a porous, crystalline, acidic metal silicate zeolite catalyst having a control index of 1-12 and an acid cracking activity (alpha) of more than 100, at least 10 p- % to convert the amount of propane to produce hydrocarbons containing up to 10% by weight of light C 2 -C 2 products such as methane and / or ethane.

The process can be optimized at a pressure of at least about 800 kPa using a catalyst consisting of a crystalline zeolite having a silica / alumina ratio of at least 12 and a containment index of 1-12 under a combination of temperature, pressure and volume flow rate (WHSV) conditions effective to convert n. 10-45% by weight of propane feed; to improve this process, sufficient C2-C15 monoolefin is added to the propane feed to increase the reaction rate of the propane feed; and a product containing at least 50% by weight of butanes is obtained

5 463 and up to 10% by weight of methane and ethane in total, calculated on the conversion of propane alone.

Instead of adding a C2-C18 mono-olefin to the propane, the alternative is to incorporate the olefin precursor into the feedstock. Examples of olefin precursors that generate the desired olefins in situ under the reaction conditions include oxidized hydrocarbons such as methanol or other C 1 -C 4 heterosubstituted organic compounds.

Advances in zeolite technology have resulted in a group of medium pore size silicon-containing materials with similar pore geometry. The most promising of these medium pore size zeolites is ZSM-5, which is usually synthesized to contain active Bronsted acid sites by attaching a tetrahedral coordinated metal such as Al, Ga or Fe to the zeolite backbone. These medium pore size zeolites are preferred for acid catalysis; However, the advantages of ZSM-5 structures can be exploited by using highly silicon-containing materials or crystalline metal silicate with one or more tetrahedral compounds with varying degrees of acidity. The crystal structure of ZSM-5 is easily identified from its X-ray diffraction pattern described in U.S. Patent No. 3,702,866 to Argauer et al.

The metal silicate catalysts useful in the process of this invention may contain a silicon-containing zeolite commonly known as the shape-selective ZSM-5 type. Members of the class of zeolites useful for such catalysts have an effective pore size, which is generally about 5-8 Å, so it freely sorbs normal hexane. In addition, the structure must provide delayed entry for larger molecules. Sometimes it is possible to deduce from a known crystal structure whether such a delayed entry exists. For example, if the only pore windows of the crystal are formed by 8-membered rings of silicon and aluminum atoms, then the entry of mole7 channels with a cross section larger than normal hexane is excluded and the zeolite is not of the desired type. The windows of 10-membered rings are preferred, although in some cases ring corrugation or pore clogging may render these zeolites ineffective.

Although 12-membered rings would not theoretically provide sufficient retardation to produce favorable conversions, it is observed that the corrugated 12-ring structure of TMA offset indeed shows some retarded input. There may be other 12-ring structures that may function for other reasons, and therefore the present invention does not fully evaluate the utility of a particular zeolite solely on the basis of theoretical structural considerations.

A suitable measure of the amount to which a zeolite causes various porous molecules to be prevented from entering its internal structure is the zeolite containment index. Alloys that provide very limited entry into and exit from the internal structure have a high containment index value, and such soles usually have small pore sizes, e.g., less than 5 Å. On the other hand, zeolites that provide relatively free entry into the inner structure of the zeolite have a low containment index value and usually have large pores, e.g., greater than 8 A. The method for determining the containment index is fully described in U.S. Patent No. 4,016,218 (Haag et al. ). It is noted that the containment index is determined using the hydrogen form of the zeolite, but that the property is thought to be a hallmark of the crystal structure.

The restraint index (CI) values ​​for some typical materials are shown in Table 1.

table 1

<td></td><td>zeolite</td><td>CI</td><td>(at the test temperature</td>

<td> 5</td><td>ZSM-5</td><td> 6-8,3</td><td>(371 ° C-316 ° C)</td>

<td></td><td>ZSM-11</td><td> 5-8,7</td><td>(371 ° C-316 ° C)</td>

<td></td><td>ZSM-12</td><td> 2,3</td><td>(316 ° C)</td>

<td></td><td>ZSM-20</td><td> 0,5</td><td>(371 ° C)</td>

<td></td><td>ZSM-22</td><td> 7,3</td><td>(427 ° C)</td>

<td> 10</td><td>ZSM-23</td><td> 9,1</td><td>(427 ° C)</td>

<td></td><td>ZSM-35</td><td> 4,5</td><td>(454 ° C)</td>

<td></td><td>ZSM-38</td><td> 2</td><td>(510 ° C)</td>

<td></td><td>ZSM-48</td><td> 3,5</td><td>(538 ° C)</td>

<td></td><td>ZSM-50</td><td> 2,1</td><td>(427 ° C)</td>

<td> 15</td><td>TMA-offretite</td><td> 3,7</td><td>(316 ° C)</td>

<td></td><td>Zeolite beta</td><td> 0,6-2,0</td><td>(316 ° C-399 ° C)</td>

The containment index described above is an important and even critical definition of those ZSM-5 type zeolites that are useful in this invention. However, the true nature of this parameter and the technique described to determine it allow a given zeolite to be tested to some extent under different conditions and therefore have different containment indices. The Hill25 full index appears to vary somewhat depending on the severity of the operations (conversion) and the presence or absence of binders. Likewise, other variables such as the crystal size of the zeolite, the presence of adsorbed impurities, etc. can affect the containment index. Therefore, it can be appreciated that it may be possible to select the experimental conditions, e.g., temperature, to provide more than one value for the containment index of that zeolite. This explains the range of variation indices of zeolites such as ZSM-5, ZSM-II, and beta.

Examples of the class of high silicon zeolites defined herein include ZSM-5, ZSM-11, ZSM-12, ZSM-22, ZSM23, ZSM-35, ZSM-38, ZSM-48, and the like. ZSM-5 is described in U.S. Patent No. 3,702,886 (Argauer et al.). ZSM-II is described in U.S. Patent No. 3,709,979 (Chu). ZSM-12 is described in U.S. Patent No. 3,832,449 (Rosinski et al.). ZSM-22 is described in U.S. Patent No. 4,046,859 (Plank et al.). ZSM-23 is described in U.S. Patent No. 4,077,842 (Plank et al.). ZSM-35 is described in U.S. Patent No. 4,016,245 (Plank et al.). ZSM-38 is described in U.S. Patent No. 4,046,859 (Plank et al.). ZSM-48 is described in U.S. Patent No. 4,397,827 (Chu). In a preferred example, the catalyst of this invention consists of aluminosilicate alloy H-ZSM-5.

In the present invention, it is desirable to use zeolite variants having at least a reasonable amount of Bronsted acid activity. A zeolite with a low silica / alumina ratio (e.g., 20: 1 to 100: 1) is usually preferred because the cracking activity of the previous acid, as measured by alpha, is higher, typically about 100-500. An alpha experiment that provides a measure of the relative rate constant of a zeolite for the cracking of normal hexane (i.e., alpha value) have been described by Miale et al., Journal of Catalysis, Vol. 6, No. 2, October 1966 and are incorporated herein by reference as if fully presented.

The zeolite component of the catalyst may be the only component, i.e. it may have been formed into granules using known methods, and in such a shaped form it may serve as an effective catalyst in the process of this invention. The zeolite can be mixed with a binder, such as alumina, to form catalyst particles by extrusion or other methods known in the art. Compression particles containing approx. 65 wt% zeolite and 35 wt% alumina binder are examples of a catalyst suitable for use in the process of this invention.

Although the process of this invention can be carried out without a hydrogenation component, in some cases the presence of such a component results in an increase in activity and / or selectivity. Platinum metal works this way. Other metals that may facilitate hydrogenation dehydration or olefin disproportionation, such as Group VIII Fe or Pt metals of the Periodic Table (IUPAC), Group Hb metals, titanium, vanadium, chromium, molybdenum, tungsten, rhenium and gallium, may be useful. .

For purposes of this invention, catalytic conversion is accomplished by a combination of feed composition (propane / olefin ratio), temperature, pressure, and volume flow rate (WHSV) conditions that are effective in converting at least wt% of the propane feed and effective in providing selectivity to aliphatic C4.⁺-carbohydrates of at least

35 wt% and preferably between about 45-95 wt%. The remainder is converted mainly to aromatic C5⁺hydrocarbons, as described by way of example below. Since many combinations of feed configuration, temperature, pressure, and WHSV produce conversion and selectivity in the desired range, it is apparent that under such conditions it becomes difficult to define very simply usable ranges for four individual parameters that are independent of each other. Preferably, the reaction is carried out at about 200-400 ° C, and most preferably at about 200-370 ° C, above about.

2850 at a pressure of kPa, at a volume flow rate per hour of about 0.01-5, with a feed composition having a propane: olefin ratio of about 1.5: 1-9: 1 and substantially without added hydrogen. The described conditions achieve useful aliphatic C4⁺hydrocarbon yields in a single run without experiencing rapid aging of the catalyst.

This invention includes the step of fractionally distilling a hydrocarbon product of isobutane, a C3-C4 hydrocarbon stream rich in unreacted propane, a C2 hydrocarbon stream, and

C5^_to obtain a hydrocarbon stream. Unconverted propane can be separated and recycled to a solid bed reaction zone packed with HZSM-5 catalyst.

In a preferred embodiment of the process, in a fixed bed reaction zone, under mixed conditions, a mixed feed containing propane and a monoolefin or olefin precursor is contacted with a porous, crystalline acidic metal silicate zeolite catalyst having a decomposition index of at least 20 to convert a percentage by volume of propane, the hydrocarbon product is removed from the reaction zone, containing up to 10% by weight of cracked products consisting of methane and ethane and separating a hydrocarbon stream consisting essentially of unreacted propane, a hydrocarbon product and circulating the stream to the solid bed reaction zone in an amount sufficient to maintain a propane content of about 60-90% by weight in a mixed feed. An improvement over the prior art is a new aspect of the present invention which results in the addition of valuable aliphatic C4⁺-increased yields of hydrocarbons such as butanes and pentanes comprises separating the product to obtain a first fraction consisting essentially of unreacted propane and a second fraction consisting of aliphatic and aromatic C4⁺hydrocarbons; recycling the first propane-rich fraction to be mixed with the olefin-rich feed stream to maintain a combined feed stream containing about 80-90 wt% propane and about 10-40 wt% propylene; and introducing a combined feed stream into the reaction zone for catalytic conversion.

It is an object of the present invention to produce valuable hydrocarbons such as butanes and pentanes and to limit the formation of undesirable by-products such as methane and ethane. In a preferred embodiment, the product contains at least 10% C4 aliphatic⁺hydrocarbons. The cracking of propane into methane and ethane is kept to a minimum, preferably at most 10% by weight of the final product in this process. This is achieved by adjusting the reaction parameters including the feed composition.

It is also an object of the present invention to limit the production of aromatic hydrocarbons and to obtain a higher aliphatic C₄⁺hydrocarbon yield than previously achieved.

Preferably, the liquid product of the solid bed catalytic reaction contains up to 40% by weight of aromatics.

Figure 1 shows a comparison of substantially pure propane and a 9: 1 mixture of propane and propylene when used as feedstocks in the catalytic conversion reaction of this invention. Feeding propylene together with propane improves the rate of propane conversion, especially in a short volume time (1 / WHSV). The increased reactivity of propane caused by the presence of limited amounts of added olefin allows for high propane conversion at higher volume flow rates than is achieved when propane alone is converted. The operation of a high volume flow rate results in greater propane conversion throughout and smaller, more economical reactors. In addition, product selectivities are improved at higher volume flow rates, as cracking reactions that produce undesirable light products such as methane and / or ethane are minimized.

Table 2 shows the product selectivities obtained in the reactions of Figure 1, assuming that in the case of a mixed feed, all added olefin is converted to Cg.⁺hydrocarbons. The results in Table 2 show that the addition of olefin to the propane feed improves the selectivity of pentane, reduces the cracking of propane to methane and ethane, and improves the rate of propane conversion by one order of magnitude. The product selectivities of each feed at 312 ° C and 6184 kPa and 20% propane conversion above ZSM-5 catalyst are as follows:

Table 2

<td>Pass 5</td><td>WHSV</td><td>^C1</td><td>c₂</td><td>iC₄</td><td>nC₄</td><td>c₅⁺</td><td>c₆⁺liquid</td>

<td>propane</td><td> 0,1</td><td> 6,4</td><td>Well</td><td> 30,1</td><td> 39,3</td><td> 10,9</td><td> 2,4</td>

<td>propane / propylene (90:10)</td><td> 2,0</td><td> 0,0</td><td> 0,4</td><td> 25,4</td><td> 34,5</td><td> 23,8</td><td> 15,8</td>

Figure 2 compares the amount of propane conversion as a function of temperature. The propane feed has been diluted with 10 wt% propylene. The pressure is kept constant at 6184 kPa. At 230 ° C, the conversion of the mixed feed is limited to less than 20% by weight, while at higher temperatures (e.g., 300 ° C and above) the conversion of propane increases to more than 20% by weight.

The product selectivity curves for a mixed hydrocarbon feed containing 90 wt% propane and 10 wt% propylene are plotted in Figure 3. The feed volume flow rate per hour (WHSV) is 0.8 and the pressure is kept constant at 6184 kPa. The maximum point of production of normal and isobutanes is at about 312oC. At this temperature there is also a minimum point on the curve corresponding to the aliphatic and aromatic Cg⁺the amount of hydrocarbons in the product. The amount of cracked products, methane and ethane in the total product yield increases as the temperature rises.

Figure 4 shows the relationship between the amount of reacted propane and the reaction temperature when the feed composition contains

20 wt% propane and 80 wt% propylene. The conversion of propane decreases as the reaction temperature rises when the feed contains n.

p-% monoolefin. This effect is most dramatically observed in the case of lower volume flow rates e.g.

when the olefin-rich feed (20 wt% propane, 35 80 wt% propylene) has a volumetric flow rate per hour (WHSV) of

0.1. In such a case, at temperatures of about 285 ° C and higher, a negative conversion of propane occurs, i.e., propane is actually formed in the reaction. Table 3 shows the product selectivities obtained in the reaction of Figure 4 at 230 ° C and a WHSV of 0.1 assuming that all olefins are converted to Cg.⁺hydrocarbons.

Table 3 WHSV Οχ C of propane₂ iC ^ n-C4 C5 · * · conversion,%

43,4 0,1 0,0 0,0 29,6 12,1 58,2

Figure 5 shows a comparison between the experimental results of mixed feed propane conversion and the equilibrium predictions. When the molar fractions of propane are 0.5 or less, a negative conversion of the propane feed occurs when the reaction produces propane. These results indicate the importance of the propane / propylene feed ratio 15 in the control of propane conversion. Propane conversion is greatest when the propane / propylene feed ratio is greater than about 1.5: 1.

Figure 6 shows the optimum temperature range for the conversion of four different propane / propylene mixed feeds. For feedstocks containing about 80-90 wt% propane and about 10-20 wt% propylene, the optimum temperature range for propane conversion is about 315-400 ° C.

In a general example, this invention is useful in refining the C3 fraction from FCC25 exhaust gas units. The C3 fraction containing substantially about 40% by weight of propane and 60% by weight of propylene is contacted under conversion conditions in a solid bed reaction zone with a crystalline, acidic metal silicate catalyst to partially convert the propane to higher molecular weight hydrocarbons. The effluent from the reaction zone is recovered and then distilled to an isobutane stream, C5⁺to a hydrocarbon stream, C₂“-K: as a gas stream and as a C3-C4 hydrocarbon stream. Propane is separated from the C3-C4 stream and recycled to the solid bed reaction zone. This recycle stream is used to maintain a propane content of about 60-90% by weight in the mixed feed composition.

The following examples are included to illustrate the advantages of this invention.

Example 1

The liquid feed, which consists of propane, is charged to a continuous tubular packed bed reactor containing about 11 g of crushed HZSM-5 catalyst. The silica / alumina ratio of the catalyst is 70 and the acid cracking (alpha) value is 194. The liquid propane is evaporated by a heating device in a state above the catalyst bed. The gas and vapor products are analyzed by an in-line gas chromatograph. Liquid products are collected and analyzed separately from the line by gas chromatography. This is a comparative example and as such does not form part of this invention. The results of the experiment are shown in Table 4 below.

Table 4

Driving 1__________ Driving 2

<td>operating time (B)</td><td> 8</td><td> 25</td><td> 31</td><td> 19</td><td> 25</td><td> 42</td><td> 48</td><td> 66</td>

<td>temperature (° C)</td><td> 312</td><td> 312</td><td> 312</td><td> 312</td><td> 367</td><td> 367</td><td> 367</td><td> 367</td>

<td>pressure (kPa)</td><td> 2060</td><td> 2060</td><td> 6181</td><td> 6181</td><td> 6181</td><td> 6181</td><td> 2060</td><td> 2060</td>

<td>WHSV</td><td> 0,5</td><td> 0,1</td><td> 0,5</td><td> 0,1</td><td> 0,5</td><td> 0,1</td><td> 0,5</td><td> 0,1</td>

<td>propane conversion,%</td><td> 4</td><td> 12</td><td> 5</td><td> 19</td><td> 43</td><td> 57</td><td> 33</td><td> 44</td>

Table 4 (continued)

Driving 1__________ Driving 2

<td rowspan="2"> 5</td><td colspan="2">Product yield (wt%)</td><td rowspan="2"> 0,8 1,3</td><td rowspan="2"> 0,3 0,4</td><td rowspan="2"> 1,2 2,1</td><td rowspan="2"> 3,4 7,9</td><td rowspan="2"> 9,3 23,9</td><td rowspan="2"> 1,8 3,6</td><td rowspan="2"> 3,7 11,3</td>

<td>methane ethane</td><td> 0,2 0,3</td>

<td> 10</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td>

<td></td><td>propane</td><td> 96</td><td> 88</td><td> 95</td><td> 81</td><td> 57</td><td> 43</td><td> 67</td><td> 56</td>

<td></td><td>propylene</td><td> 0</td><td> 0</td><td> 0</td><td> 0</td><td> 0,1</td><td> 0</td><td> 0</td><td> 0</td>

<td> 15</td><td>isobutane</td><td> 1</td><td> 4</td><td> 2</td><td> 6</td><td> 9</td><td> 58</td><td> 8</td><td> 7</td>

<td></td><td>n-butane</td><td> 1</td><td> 5</td><td> 2</td><td> 7</td><td> 12</td><td> 7</td><td> 11</td><td> 11</td>

<td> 70</td><td>^c5</td><td> 0,3</td><td> 1,0</td><td> 0,5</td><td> 2</td><td> 7</td><td> 4</td><td> 5</td><td> 6</td>

<td></td><td>c₆⁺</td><td> 0,5</td><td> 0,6</td><td> 0,5</td><td> 0,7</td><td> 4</td><td> 7</td><td> 4</td><td> 6</td>

Selektllvisyys

<td> 25</td><td colspan="9">(Wt%)</td>

<td></td><td>methane</td><td> 5</td><td> 7</td><td> 5</td><td> 6</td><td> 8</td><td> 16</td><td> 5</td><td> 8</td>

<td> 30</td><td>ethane</td><td> 7</td><td> 11</td><td> 9</td><td> 11</td><td> 18</td><td> 42</td><td> 11</td><td> 26</td>

<td></td><td>isobutane</td><td> 32</td><td> 30</td><td> 29</td><td> 30</td><td> 21</td><td> 10</td><td> 23</td><td> 16</td>

<td></td><td>n-butane</td><td> 36</td><td> 41</td><td> 39</td><td> 39</td><td> 28</td><td> 13</td><td> 33</td><td> 24</td>

<td> 35</td><td>^c5</td><td> 7</td><td> 8</td><td> 10</td><td> 11</td><td> 16</td><td> 7</td><td> 15</td><td> 13</td>

<td></td><td>c₆⁺</td><td> 13</td><td> 5</td><td> 9</td><td> 4</td><td> 9</td><td> 12</td><td> 13</td><td> 13</td>

Example 2

A liquid feed consisting of a mixture of propane (88 wt%) and propylene (12 wt%) is charged to a continuous tubular packed bed reactor containing about 11 g of the catalyst described in Example 1. The liquid mixed feed is evaporated by a heater located in the part above the catalyst bed. The results of the experiment are shown in Table 5 below.

5 4 63

Table 5

<td></td><td>operating time</td><td colspan="3">Driving 1 Driving 2</td>

<td> 5</td><td>(B)</td><td> 17</td><td> 23</td><td> 7</td>

<td></td><td>temperatures ° C)</td><td> 312</td><td> 312</td><td> 312</td>

<td></td><td>pressure (kPa)</td><td> 6181</td><td> 6181</td><td> 6181</td>

<td> 10</td><td>WHSV</td><td> 0,1</td><td> 0,5</td><td> 0,8</td>

<td></td><td>propane conversion,%</td><td> 28</td><td> 19</td><td> 17</td>

<td> 15</td><td>Product yield (wt%)</td><td></td><td></td><td></td>

<td> 20</td><td>methane</td><td> 1,2</td><td> 0,3</td><td> 0,2</td>

<td></td><td>ethane</td><td> 3</td><td> 0,7</td><td> 0,4</td>

<td> 25</td><td>propane</td><td> 63</td><td> 72</td><td> 73</td>

<td></td><td>propylene</td><td> 0</td><td> 0,1</td><td> 0,1</td>

<td></td><td>isobutane</td><td> 10</td><td> 8</td><td> 7</td>

<td> 30</td><td>n-butane</td><td> 11</td><td> 10</td><td> 10</td>

<td></td><td>^c5</td><td> 7</td><td> 4</td><td> 4</td>

<td> 35</td><td>c₆⁺</td><td> 5</td><td> 5</td><td> 5</td>

<td></td><td colspan="2">Selectivity</td><td></td><td></td>

<td></td><td>(Wt%)</td><td></td><td></td><td></td>

<td> 40</td><td>methane</td><td> 3,2</td><td> 1,0</td><td> 0,6</td>

<td></td><td>ethane</td><td> 8</td><td> 2,4</td><td> 1,7</td>

<td> 45</td><td>isobutane</td><td> 28</td><td> 27</td><td> 27</td>

<td></td><td>n-butane</td><td> 31</td><td> 36</td><td> 37</td>

<td></td><td>^c5</td><td> 18</td><td> 15</td><td> 16</td>

<td> 50</td><td>c₆⁺</td><td> 12</td><td> 18</td><td> 18</td>

<td colspan="2">Driving 3</td><td colspan="4">Driving 4</td>

<td> 7</td><td> 25</td><td> 31</td><td> 6</td><td> 24</td><td> 29</td>

<td> 312</td><td> 312</td><td> 312</td><td> 230</td><td> 230</td><td> 367</td>

<td> 2060</td><td> 2060</td><td> 2060</td><td> 6181</td><td> 6181</td><td> 6181</td>

<td> 0,8</td><td> 0,1</td><td> 0,5</td><td> 0,8</td><td> 0,1</td><td> 0,8</td>

<td> 15</td><td> 20</td><td> 15</td><td> 0,4</td><td> 7</td><td> 41</td>

<td> 0,1</td><td> 0,7</td><td> 0,3</td><td> 0</td><td> 0</td><td> 2</td>

<td> 0,3</td><td> 2</td><td> 0,6</td><td> 0</td><td> 0</td><td> 5</td>

<td> 75</td><td> 70</td><td> 75</td><td> 88</td><td> 82</td><td> 52</td>

<td> 0</td><td> 0</td><td> 0</td><td> 0</td><td> 0,1</td><td> 0</td>

<td> 7</td><td> 10</td><td> 7</td><td> 2</td><td> 3</td><td> 10</td>

<td> 9</td><td> 11</td><td> 10</td><td> 1</td><td> 2</td><td> 12</td>

<td> 4</td><td> 5</td><td> 4</td><td> 2</td><td> 3</td><td> 7</td>

<td> 5</td><td> 3</td><td> 4</td><td> 8</td><td> 10</td><td> 14</td>

<td> 0,3</td><td> 2,4</td><td> 1</td><td> 0</td><td> 0</td><td> 4</td>

<td> 1,2</td><td> 6,4</td><td> 2,4</td><td> 0</td><td> 0</td><td> 11</td>

<td> 27</td><td> 32</td><td> 29</td><td> 13</td><td> 15</td><td> 19</td>

<td> 35</td><td> 36</td><td> 38</td><td> 4</td><td> 10</td><td> 24</td>

<td> 18</td><td> 15</td><td> 15</td><td> 16</td><td> 17</td><td> 14</td>

<td> 19</td><td> 8</td><td> 15</td><td> 68</td><td> 57</td><td> 29</td>

5 4 63

Table 5 (continued)

Driving 5

<td></td><td colspan="4">operating time</td>

<td> 5</td><td>(B)</td><td> 5</td><td> 24</td><td> 29</td>

<td></td><td>Temp (° C)</td><td> 367</td><td> 367</td><td> 367</td>

<td></td><td>Pressure (kPa)</td><td> 6181</td><td> 6181</td><td> 6181</td>

<td> 10</td><td>WHSV</td><td> 0,5</td><td> 0,1</td><td> 0,2</td>

<td></td><td>propane conversion,%</td><td> 25</td><td> 57</td><td> 47</td>

<td> 15</td><td>Product yield (wt%)</td><td></td><td></td><td></td>

<td> 20</td><td>methane</td><td> 1,6</td><td> 7</td><td> 7</td>

<td></td><td>ethane</td><td> 4</td><td> 19</td><td> 18</td>

<td></td><td>propane</td><td> 66</td><td> 38</td><td> 47</td>

<td> 25</td><td>propylene</td><td> 1,3</td><td> 0</td><td> 0</td>

<td></td><td>isobutane</td><td> 7</td><td> 5</td><td> 7</td>

<td> 30</td><td>n-butane</td><td> 7</td><td> 6</td><td> 8</td>

<td></td><td>^c5</td><td> 5</td><td> 4</td><td> 4</td>

<td></td><td rowspan="2">c₆⁺</td><td> 8</td><td> 21</td><td> 8</td>

<td> 35</td><td></td><td></td><td></td>

<td></td><td colspan="2">Selectivity</td><td></td><td></td>

<td></td><td>(Wt%)</td><td></td><td></td><td></td>

<td> 40</td><td>methane</td><td> 5</td><td> 11</td><td> 14</td>

<td></td><td>ethane</td><td> 13</td><td> 31</td><td> 34</td>

<td></td><td>isobutane</td><td> 20</td><td> 8</td><td> 13</td>

<td> 45</td><td>n-butane</td><td> 22</td><td> 10</td><td> 16</td>

<td></td><td>C5</td><td> 16</td><td> 6</td><td> 8</td>

<td> 50</td><td>c₆⁺</td><td> 24</td><td> 34</td><td> 16</td>

<td> 48</td><td> 53</td><td> 72</td><td> 77</td><td> 96</td><td> 102</td>

<td> 422</td><td> 422</td><td> 422</td><td> 312</td><td> 312</td><td> 312</td>

<td> 6181</td><td> 6181</td><td> 6181</td><td> 6181</td><td> 6181</td><td> 6181</td>

<td> 0,2</td><td> 0,8</td><td> 0,1</td><td> 0,8</td><td> 0,2</td><td> 0,8</td>

<td> 69</td><td> 62</td><td> 86</td><td> 18</td><td> 25</td><td> 19</td>

<td> 14</td><td> 7</td><td> 21</td><td> 0,1</td><td> 0,2</td><td> 0</td>

<td> 28</td><td> 18</td><td> 36</td><td> 0,2</td><td> 0,6</td><td> 0,2</td>

<td> 28</td><td> 38</td><td> 14</td><td> 74</td><td> 69</td><td> 72</td>

<td> 0</td><td> 0</td><td> 0,1</td><td> 0</td><td> 0</td><td> 0,1</td>

<td> 3</td><td> 4</td><td> 1</td><td> 5</td><td> 7</td><td> 5</td>

<td> 5</td><td> 6</td><td> 1,5</td><td> 7</td><td> 9</td><td> 7</td>

<td> 3</td><td> 4</td><td> 1</td><td> 5</td><td> 4</td><td> 5</td>

<td> 20</td><td> 28</td><td> 27</td><td> 11</td><td> 12</td><td> 12</td>

<td> 19</td><td> 11</td><td> 24</td><td> 0,2</td><td> 0,6</td><td> 0,2</td>

<td> 38</td><td> 27</td><td> 41</td><td> 0,8</td><td> 1,6</td><td> 0,6</td>

<td> 5</td><td> 6</td><td> 1</td><td> 18</td><td> 22</td><td> 17</td>

<td> 6</td><td> 9</td><td> 2</td><td> 25</td><td> 28</td><td> 24</td>

<td> 4</td><td> 5</td><td> 1</td><td> 18</td><td> 13</td><td> 18</td>

<td> 28</td><td> 41</td><td> 31</td><td> 39</td><td> 36</td><td> 41</td>

Table 5 (continued) Run 6 operating time

<td>(B)</td><td> 7</td><td> 25</td><td> 31</td><td> 49</td>

<td>temperature (° C)</td><td> 312</td><td> 312</td><td> 422</td><td> 422</td>

<td>pressure (kPa)</td><td> 6181</td><td> 6181</td><td> 6181</td><td> 6181</td>

<td>WHSV</td><td> 0,5</td><td> 0,11</td><td> 0,25</td><td> 0,1</td>

<td>propane conversion,%</td><td> 15</td><td> 20</td><td> 69</td><td> 84</td>

The product

<td colspan="5">to (wt%)</td>

<td>methane</td><td> 0,1</td><td> 0,4</td><td> 15</td><td> 21</td>

<td>ethane</td><td> 0,2</td><td> 0,9</td><td> 31</td><td> 37</td>

<td>propane</td><td> 75</td><td> 71</td><td> 27</td><td> 14</td>

<td>propylene</td><td> 0,1</td><td> 0</td><td> 0</td><td> 0,1</td>

<td>isobutane</td><td> 6</td><td> 8</td><td> 3</td><td> 1</td>

<td>n-butane</td><td> 8</td><td> 10</td><td> 4</td><td> 2</td>

<td>^c5</td><td> 5</td><td> 4</td><td> 2</td><td> 1</td>

<td>c₆⁺</td><td> 6</td><td> 6</td><td> 19</td><td> 24</td>

Selectivity

<td colspan="5">(Wt%)</td>

<td>methane</td><td> 0,3</td><td> 1,3</td><td> 20</td><td> 24</td>

<td>ethane</td><td> 1</td><td> 3</td><td> 42</td><td> 43</td>

<td>isobutane</td><td> 23</td><td> 28</td><td> 4</td><td> 2</td>

<td>n-butane</td><td> 33</td><td> 33</td><td> 5</td><td> 2</td>

<td>^c5</td><td> 20</td><td> 15</td><td> 3</td><td> 1</td>

<td>c₆⁺</td><td> 23</td><td> 21</td><td> 26</td><td> 28</td>

Example 3

A liquid feed consisting of propane (78 wt%) and

5463 from a mixture of propylene (22% by weight) is charged to a continuous, tubular packed bed reactor containing about 11 g of the catalyst described in Example 1. The liquid mixed feed is vaporized by a heating device located in the part above the catalyst bed. The results of the experiment are shown in Table 6 below.

Table 6

Driving 1 Driving 2

<td>operating time (h)</td><td> 7</td><td> 7</td><td> 25</td><td> 31</td><td> 49</td><td> 55</td><td> 73</td><td> 79</td>

<td>temperatures ° C)</td><td> 24</td><td> 312</td><td> 312</td><td> 312</td><td> 367</td><td> 367</td><td> 367</td><td> 422</td>

<td>pressure (kPa)</td><td> 6181</td><td> 6181</td><td> 6181</td><td> 6181</td><td> 6181</td><td> 6181</td><td> 6181</td><td> 6181</td>

<td>WHSV</td><td> 0,2</td><td> 0,8</td><td> 0,1</td><td> 0,2</td><td> 0,2</td><td> 0,8</td><td> 0,2</td><td> 0,8</td>

<td>propane conversion,%</td><td> -1,7</td><td> 25</td><td> 27</td><td> 29</td><td> 42</td><td> 36</td><td> 42</td><td> 59</td>

The product

<td colspan="9">to (wt%)</td>

<td>methane</td><td> 0</td><td> 0,1</td><td> 0,9</td><td> 0,6</td><td> 5</td><td> 1</td><td> 5</td><td> 8</td>

<td>ethane</td><td> 0</td><td> 0,4</td><td> 3</td><td> 2</td><td> 15</td><td> 4</td><td> 13</td><td> 21</td>

<td>propane</td><td> 81</td><td> 60</td><td> 59</td><td> 57</td><td> 46</td><td> 51</td><td> 47</td><td> 33</td>

<td>propylene</td><td> 12</td><td> 0,1</td><td> 0</td><td> 0,1</td><td> 0</td><td> 0,1</td><td> 0</td><td> 0,1</td>

<td>isobutane</td><td> 0,7</td><td> 9</td><td> 10</td><td> 11</td><td> 7</td><td> 9</td><td> 7</td><td> 4</td>

<td>n-butane</td><td> 0</td><td> 12</td><td> 11</td><td> 12</td><td> 8</td><td> 12</td><td> 9</td><td> 6</td>

<td>c₅</td><td> 0</td><td> 6</td><td> 7</td><td> 7</td><td> 5</td><td> 7</td><td> 5</td><td> 3</td>

<td>C₆⁺</td><td> 6</td><td> 13</td><td> 11</td><td> 11</td><td> 14</td><td> 17</td><td> 15</td><td> 26</td>

Table 6 (continued)

Table 6

Run 1 Run 2 (continued)

Selectivity (p- *)

<td>methane</td><td> 0</td><td> 0,3</td>

<td>ethane</td><td> 0, 5</td><td> 1</td>

<td>isobutane</td><td> 11</td><td> 23</td>

<td>n-butane</td><td> 0</td><td> 29</td>

<td>c₅</td><td> 0,6</td><td> 15</td>

<td>C₆⁺</td><td> 88</td><td> 32</td>

<td> 2,2</td><td> 1,3</td><td> 10</td><td> 2,5</td><td> 9</td><td> 12</td>

<td> 6</td><td> 4</td><td> 28</td><td> 7</td><td> 24</td><td> 31</td>

<td> 23</td><td> 25</td><td> 13</td><td> 18</td><td> 14</td><td> 6</td>

<td> 25</td><td> 29</td><td> 15</td><td> 24</td><td> 17</td><td> 8</td>

<td> 16</td><td> 16</td><td> 8</td><td> 13</td><td> 9</td><td> 5</td>

<td> 27</td><td> 25</td><td> 25</td><td> 34</td><td> 28</td><td> 39</td>

Example 4

A liquid feed consisting essentially of a mixture of propane (20 wt%) and propylene (80 wt%) is charged to a continuous tubular packed bed reactor containing about 11 g of the catalyst described in Example 1. The liquid mixed feed is vaporized by a heating device located in the part above the catalyst bed. The results of the experiment are shown in Table 7.

<td rowspan="2"></td><td rowspan="2">Driving</td><td colspan="8">Table 7</td>

<td colspan="4"> 1</td><td colspan="4">Driving 2</td>

<td>operating time (h)</td><td> 6</td><td> 24</td><td> 29</td><td> 48</td><td> 53</td><td> 72</td><td> 77</td><td> 7</td><td> 25</td>

<td>temperatures ° C)</td><td> 202</td><td> 230</td><td> 230</td><td> 257</td><td> 257</td><td> 312</td><td> 312</td><td> 257</td><td> 257</td>

<td>pressure (kPa)</td><td> 6181</td><td> 6181</td><td> 6181</td><td> 6181</td><td> 6181</td><td> 6181</td><td> 6181</td><td> 2060</td><td> 2060</td>

<td>WHSV</td><td> 0,8</td><td> 0,1</td><td> 0,8</td><td> 0,1</td><td> 0,8</td><td> 0,1</td><td> 0,8</td><td> 0,8</td><td> 0,1</td>

<td>propane conversion,%</td><td> 14</td><td> 47</td><td> 28</td><td> 22</td><td> 33</td><td> -53</td><td> 22</td><td> 27</td><td> -19</td>

5 463

Table 7 (continued)

Driving 1

Driving 2

<td colspan="5">The product</td>

<td> 5</td><td>to (wt%)</td><td></td><td></td><td></td>

<td></td><td>methane</td><td> 0</td><td> 0</td><td> 0</td>

<td></td><td>ethane</td><td> 0</td><td> 0</td><td> 0</td>

<td> 10</td><td>propane</td><td> 17</td><td> 11</td><td> 14</td>

<td></td><td>propylene</td><td> 0</td><td> 0</td><td> 0</td>

<td> 15</td><td>isobutane</td><td> 1</td><td> 3</td><td> 1</td>

<td></td><td>n-butane</td><td> 0,3</td><td> 1,1</td><td> 0,4</td>

<td> 20</td><td>^c5</td><td> 2</td><td> 4</td><td> 2</td>

<td></td><td>c₆⁺</td><td> 79</td><td> 81</td><td> 82</td>

<td> 25</td><td colspan="2">Selectivity (P-%)</td><td></td><td></td>

<td></td><td>methane</td><td> 0</td><td> 0</td><td> 0</td>

<td></td><td>ethane</td><td> 0</td><td> 0</td><td> 0</td>

<td> 30</td><td>isobutane</td><td> 2</td><td> 3</td><td> 1</td>

<td></td><td>n-butane</td><td> 0,4</td><td> 1</td><td> 0,4</td>

<td> 35</td><td>c₅</td><td> 2</td><td> 5</td><td> 2</td>

<td></td><td>C₆⁺</td><td> 96</td><td> 91</td><td> 96</td>

<td> 0</td><td> 0</td><td> 0,3</td><td> 0</td><td> 0</td><td> 0</td>

<td> 0,1</td><td> 0</td><td> 1,1</td><td> 0,1</td><td> 0</td><td> 0</td>

<td> 16</td><td> 13</td><td> 31</td><td> 16</td><td> 15</td><td> 24</td>

<td> 0,6</td><td> 1,0</td><td> 0,9</td><td> 2</td><td> 0,7</td><td> 1,5</td>

<td> 7</td><td> 2</td><td> 10</td><td> 7</td><td> 1</td><td> 5</td>

<td> 5</td><td> 0,3</td><td> 9</td><td> 4</td><td> 0,4</td><td> 1,2</td>

<td> 9</td><td> 4</td><td> 9</td><td> 11</td><td> 3</td><td> 7</td>

<td> 64</td><td> 80</td><td> 38</td><td> 60</td><td> 80</td><td> 62</td>

<td> 0</td><td> 0</td><td> 0,4</td><td> 0</td><td> 0</td><td> 0</td>

<td> 0,1</td><td> 0</td><td> 1,6</td><td> 0,1</td><td> 0</td><td> 0,1</td>

<td> 8</td><td> 2</td><td> 15</td><td> 9</td><td> 2</td><td> 7</td>

<td> 6</td><td> 0,4</td><td> 13</td><td> 4</td><td> 0,5</td><td> 2</td>

<td> 11</td><td> 4</td><td> 14</td><td> 14</td><td> 3</td><td> 9</td>

<td> 76</td><td> 94</td><td> 56</td><td> 73</td><td> 95</td><td> 83</td>

Example 5

The catalyst described in Example 1 is saturated with an aqueous solution containing platinum and then calcined in air. The platinum content of the sample is about 0.4% by weight. About 5 g of crushed Pt-HZSM-5 catalyst granules are charged to a continuous packed bed reactor and reduced in flowing hydrogen

At 400 ° C for 16 hours. The temperature is then lowered to 260 ° C, the hydrogen stream is stopped and a liquid mixture of propane (80 wt%) and propylene (20 wt%) is fed to the reactor. The liquid mixed feed is evaporated by a heating device in the part above the catalyst bed. The results of the experiment are shown in Table 8.

<td></td><td>Driving</td><td colspan="2">Table 8 1</td>

<td>operating time (h)</td><td> 7</td><td> 31</td><td> 55</td>

<td>temperature (° C)</td><td> 260</td><td> 260</td><td> 260</td>

<td>Pressure (kPa)</td><td> 6181</td><td> 6181</td><td> 6181</td>

<td>WHSV</td><td> 1,0</td><td> 0,5</td><td> 1,8</td>

<td>propane conversion,%</td><td> 17</td><td> 19</td><td> 8</td>

The product

<td colspan="4">to (wt%)</td>

<td>methane</td><td> 0</td><td> 0</td><td> 0</td>

<td>ethane</td><td> 0,1</td><td> 0,1</td><td> 0,1</td>

<td>propane</td><td> 64,4</td><td> 63,3</td><td> 71,8</td>

<td>propylene</td><td> 0,1</td><td> 0,1</td><td> 0,1</td>

<td>isobutane</td><td> 1,4</td><td> 1,5</td><td> 0,9</td>

<td>n-butane</td><td> 0,8</td><td> 0,9</td><td> 0,3</td>

<td>^c5</td><td> 3,0</td><td> 3,2</td><td> 1,7</td>

<td>c₆⁺</td><td> 30,2</td><td> 30,9</td><td> 25,2</td>

Selectivity

<td>(Wt%)</td><td></td><td></td><td></td>

<td>methane</td><td> 0</td><td> 0</td><td> 0</td>

<td>ethane</td><td> 0,2</td><td> 0,2</td><td> 0,2</td>

<td>isobutane</td><td> 3,9</td><td> 4,1</td><td> 3,2</td>

<td>n-butane</td><td> 2,3</td><td> 2,6</td><td> 0,9</td>

<td>^c5</td><td> 8,4</td><td> 8,6</td><td> 6,0</td>

<td>c₆⁺</td><td> 85,1</td><td> 84,5</td><td> 89,7</td>

The above examples show an improvement in the conversion of propane to valuable hydrocarbons above a ZSM-5 type catalyst when a smaller amount of olefin

8 5,463 is added to the propane feed. Favorable results such as an increase in isobutane production are obtained at minimal cost to the petroleum refiner.

Although the present invention has been described with reference to certain embodiments, it is not intended to limit the idea of ​​the invention other than as set forth in the following claims.