JPS6240396B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention comprises unbranched paraffins and C ₅
Paraffins 10% by weight or more, C ₆ paraffins 10
_C5 and C6, consisting of at least 90% by weight of C5 and _C6 paraffins and up to 2% by weight of _benzene ;
This invention relates to a method for increasing the octane number of a gasoline fraction consisting of _C6 hydrocarbons. Unbranched paraffins have low octane numbers, resulting in an unfavorable effect on the octane numbers of light gasoline cuts produced from them. In order to increase the octane number of such light gasoline cuts, the unbranched paraffins present in them can be converted by isomerization into branched paraffins of the same number of carbon atoms having a higher octane number. In the isomerization of C ₅ and C ₆ paraffins, _the objective ^is to
The aim is to obtain the highest possible yields of hydrocarbons as well as the highest possible octane numbers of these hydrocarbons. The appropriate quantity to evaluate the effect of isomerization is
It is the product of the yield of C ₅ ⁺ hydrocarbons and the octane number of these hydrocarbons, and this product is referred to as P in this specification. It is generally said that high values of P must be targeted in isomerization. In the isomerization of C ₅ and C ₆ paraffin mixtures over catalysts containing one or more group noble metals on the support, a minimum hydrogen/feed molar ratio is required to prevent rapid catalyst deactivation. is required. The hydrogen/feed molar ratio applied in the isomerization is designated A in this specification. From the point of view of the costs involved in gas recirculation, it is advisable to carry out the isomerization at the lowest possible value of A. The lowest value of A at which isomerization can still occur depends on the stability of the catalyst. By isomerization at elevated temperatures and pressures in the presence of hydrogen and a fixed catalyst bed, the catalyst comprising one or more group noble metals on mordenite as a support, _C5
Extensive research has been carried out to increase the octane number of gasoline fractions of the above composition consisting of C6 and _C6 hydrocarbons. First of all, these catalysts are 1.0
We found that it has such high stability that it can be easily used with the following values of A (approximately 0.5
The value of A is considered to be the lowest value desired for practical use of these catalysts). Therefore, from the above cost perspective, including gas recirculation, A should be 1.0
If there is no special reason to choose a larger size, at least
0.5 It is preferred to use these catalysts with a value of A of at most 1.0, preferably as close as possible to 0.5.
In addition, at a certain space velocity and total pressure, the operating temperature reaches a maximum value of P (denoted by P _M )
It was found in the study that there is a special value for each feed (denoted A _M ). The highest value of P _{that can be reached at a given space velocity and total pressure and A=0.5 is denoted by P 0.5 .} From the above cost point of view, including gas recirculation, at a given space velocity and total pressure and at an associated value of A, the highest value of P, denoted by P _A , is very high, and the requirement P _A −P _{0.5 0.3} and P _{A −P 0.5}
1.0 only when 3/4 (P _M - P _0.5 ) is satisfied _.
It appears economically attractive to apply A that is larger and at most equal to A _M. If A _M
is at least 2.24, and if we choose A by A _M : a If A _M is at least 2.24 and less than 2.40, then A satisfies the relation A _M A2265・A _M ^-8 . ⁶ and if b A _M is at least 2.40, then A is the relation A _M
It was found that the above requirements are _met . In all cases where A _M is less than 2.24, it is preferred to apply an A of at least 0.5 and at most 1.0. A _M is expressed by the formula: A _M =340·B ⁰ . ⁴・C ⁴・(1-3D)/1
+ ^100C4 (where B=weight fraction of _C6 paraffins in the feed calculated for _C5 + _C6 paraffins C=8510.5.BE/22(1+B) D=C in the feed weight fraction of components other than ₅ and C ₆ paraffins, and E = octane number of C ₅ + C ₆ paraffins in the feed. The present invention therefore comprises unbranched paraffins and contains at least 10% by weight of _C5 paraffins, at least 10% by weight of _C6 paraffins, at least 90% by weight of _C5 and _C6 paraffins, and at most 2% by weight of benzene. NaruC ₅
and a gasoline fraction consisting of C ₆ hydrocarbons,
Hydrogen/feed molar ratio (A) based on A _M below: a If A _M is less than 2.24, then A is at least
0.5 and at most 1.0. b If A _M is at least 2.24 and less than 2.40, then A is greater than 1.0, and A satisfies ^the following relationship: A _M A2265·A _M ^-8.6 , and C A _M is at least 2.40, then A is greater than 1.0, and A satisfies the following relationship: A _M A0.5A _M , (A _M is as above), and at elevated temperature and pressure, Contact with a fixed catalyst bed in the presence of hydrogen (working temperature 150-280
C), the catalyst relates to a process for increasing the octane number of light gasoline cuts, the catalyst comprising one or more group noble metals on mordenite as a support. If the process according to the invention is applied to feeds of composition such that A _M is less than 2.24, it is preferably done with an A of less than 0.75. The process of the invention is carried out at elevated temperature and pressure and in the presence of hydrogen and a catalyst. Suitable reaction conditions are a temperature of 150-280°C, a pressure of 3-50 bar and a space velocity of 0.5-10 kg of feed per kg of catalyst per hour.
It is. The reaction is preferably carried out under the following conditions: temperature 230-280 DEG C., pressure 10-40 bar and space velocity 1.0-5.0 Kg/Kg catalyst per hour. The process according to the invention uses a catalyst consisting of one or more noble metals of the Group on mordenite as a support. For this purpose, H-type mordenite is preferred, meaning that the metal cations originally present in mordenite are replaced by hydrogen ions. This substitution is suitably carried out by treating the mordenite with an acid or an ammonium compound. Preferably, mordenite is treated with an acid,
In particular, treatment is carried out successively with an aqueous solution of hydrochloric acid and with an aqueous solution of an ammonium compound, especially ammonium nitrate. It is further preferred to repeat the acid treatment or the treatment with an ammonium compound or both several times. After treatment with ammonium compounds, mordenite is in the ammonium form. By sintering the ammonium mordenite, the nitrogen atoms introduced during the treatment are removed from the mordenite, yielding H-type mordenite. Group noble metals that can be present on mordenite are platinum, palladium, rhodium, ruthenium, iridium and osmium. Platinum is preferred. Optionally, the catalyst consists of two or more Group noble metals. The amount of group noble metal present on the prepared catalyst is between 0.01 and 5% by weight, especially
Preferably it is 0.1-1.5% by weight. Group noble metals can be prepared by well-known methods such as impregnation,
Place it on mordenite by ion exchange, precipitation, etc. Preferably, the group noble metal is loaded onto the mordenite from an aqueous solution in which the metal is present in cationic form. Particular preference is given to ammonia solutions in which the group noble metals are present in the form of cationic complexes.
For the production of catalysts that can be used in the present invention, the support material does not necessarily have to consist entirely of mordenite. Mixtures of mordenite and inert binder substances are likewise suitable as supports for the catalysts of the invention. The invention is further illustrated in the following examples. Example Production of Pt/H mordenite catalyst Sodium mordenite (NORTON
A mixture of 20 g of ZEOLON powder and 200 ml of 1.5N hydrochloric acid was boiled under reflux for 1 hour. The solid material was filtered and washed with water. The solid material was then boiled under reflux with 200 ml of 1.0 molar ammonium nitrate solution for 1 hour. This ammonium nitrate treatment was repeated twice with fresh nitrate solution each time. After each treatment, the solid material was filtered and washed with water. Finally, the solid substance
It was mixed with 100 ml of an aqueous solution containing 0.07 g of Pt(NH ₃ ) ₄ Cl ₂ and stirred for 2 hours at room temperature. The solid material was filtered, dried at 120°C, pelletized and ground at 50 tons of pressure. A portion with a particle size of 0.2-0.6 mm was isolated from the ground material using a sieve. 500
The catalyst was converted to a Pt/H mordenite catalyst by calcination at ℃ for 3 hours. Increasing the octane number of light gasoline fractions consisting of C ₅ and C ₆ hydrocarbons in a cylindrical reactor with a fixed bed of catalyst prepared as described above.
Several isomerization experiments were conducted to increase the octane number of the seed light gasoline fraction (feed~). All isomerization experiments were carried out at a pressure of 15 bar and a space velocity of 21·1 ^-1 ·h ^-1 . With the exception of Feed V, which contained 6.5% by weight of other non-aromatic hydrocarbons apart from _C5 and _C6 paraffins, all other feeds consisted entirely of _C5 and _C6 paraffins.
For each of the feeds ~, isomerization experiments were carried out at a hydrogen/feed molar ratio of 0.5 and a temperature such that the highest value of P (P _{0 .5} ) reached at this value of A was reached (Experiments 1 ~ 9). We thus found a dependent value _of P _0.5 for each feed. Experimentally determined values for B and E, values for C and values for D calculated by the formula: C=85-10.5.B-E/22(1+B) (feeds other than feed V with D=0.065) With the help of D=0), the formula: A _M =340·B ⁰ . ⁴・C ⁴・(1-3D)/1+
A _M was calculated for each of the feeds at ^100C4 . Isomerization experiments were carried out with each of the feeds ~ (runs 10-18) at hydrogen/feed molar ratios A _M and temperatures such that the highest value of P reachable at this value of A (P _M ) was reached. . We thus found a dependent value of P _M for each feed. The difference between P _M and _{P 0.5} is the highest achievable increase in P that can be reached by applying the value of A corresponding to A _M. A meets at least the requirements P _A - _{P 0.5 0.3} and P _A - _{P 0.5 3/4} (P _M
-P _0.5 ) is _the value that must satisfy formula A.
2265A _M ^-8.6 (if 2.40>A _M 2.24) ^and A
Calculated by the value found for A _M at 0.5 A _M (if A _M 2.40). Three isomerization experiments were performed for each of the feeds ~, each with a hydrogen/feed molar ratio of 1.0 (runs 19-27),
1.5 (Experiments 28-36) and 3.0 (Experiments 37-45) and the highest value of P that can be reached at the applied value of A (P
_A ). P _A and _{P 0.5}
is the increase in P reached in that experiment. Experimental results and values of feed B, C, E
The values of and A _M are shown in the table.

【table】

[Table] Regarding the experiments conducted (1 to 45), please note the following points. Experiments 1, 5-7, 9, 11-13, 17, 19, 23-
25, 27, 29, 30, 35 and 40 are experiments according to the present invention. Other experiments are outside the scope of the present invention and are for comparison purposes. Experiments 1, 5-7 and 9 (carried out with A=0.5) The requirement 1.0A0.5 was met in these experiments for feeds with A _M <2.24. Experiments 2-4 (Carried out with A=0.5) The requirement A0.5 A _M was not met in these experiments for feeds with A _M >2.40. Experiment 8 (Carried out with A = 0.5) In the experiment with a feed ^of 2.40 > A _M > 2.24, the requirement A2265 A _M ^-8.6 was not met. Runs 10, 14-16 and 18 (carried out with A=A _M ) The requirement A1.0 was not met in these experiments for feeds with A _M <2.24. Experiments 11-13 (Carried out with A=A _M ) The requirement A _M A0.5 A _M was fulfilled in these experiments for feeds with A _M >2.40. Experiment 17 (Carried out with A = A _M ) The requirement A _M A2265 ^A _M ^-8.6 was met in this experiment for a feed with 2.40 > A _M > 2.24. Runs 19, 23-25 and 27 (carried out with A=1.0) The requirement 1.0A _M 0.5 was met in these experiments for feeds with A _M <2.24. Runs 20-22 (Carried out with A=1.0) The requirement A0.5A _M was not met in these experiments for feeds with A _M >2.40. In these experiments, P _A -P _0.5 was less _than 3/4 ( _{P M} -P _0.5 ). Furthermore, in experiments 20 and 21, P _A −P _{0.5 is} 0.3
It was smaller. Experiment 26 (Carried out with A=1.0) The requirement A2265.A _M ^-8.6 was not met in this experiment for a feed with 2.40> ^A _M >2.24. In this experiment, P _A −P _0.5 is less _than 0.3, and P
_A −P _0.5 was less _than 3/4 (P _{M −P 0.5} ). Runs 28, 32-34 and 36 (carried out with A=1.5) The requirement A1.0 was not met in these experiments for feeds with A _M >2.24. Experiments 29 and 30 (carried out with A=1.5) The requirement A _M A0.5 A _M was met in these experiments for feeds with A _M >2.40. In these experiments, P _A −P _0.5 is greater than 0.3, and P _A −P 0.5 _is greater than 0.3;
_0.5 was greater than _3/4 (P _M −P _0.5 ) _. Experiment 31 (Carried out with A = 1.5) In this experiment for feeds with A _M >2.40 the requirement A _M
0.5A _M was not satisfied. In this experiment, P _A −P ₀ .
₅ was smaller than 3/4 (P _M - _{P 0.5 )} . Experiment 35 (Carried out with A=1.5) In this experiment for feeds with 2.40>A _M >2.24 ^the requirement A _M A2265 A _M ^-8.6 was met. In this experiment, P _A −P _0.5 is greater _than 0.3, and P _A
-P _0.5 was greater _than 3/4 (P _{M -P 0.5} ). Runs 37, 41-43 and 45 (carried out with A=3.0) The requirement A _M 1.0 was not met in these experiments for feeds with A _M <2.24. Experiments 38 and 39 (Carried out with A=3.0) The requirement AA _M was not met in these experiments for feeds with A _M >2.40. Experiment 40 (Carried out with A = 3.0) In this experiment for a feed with A _M >2.40 the requirement A _M
A0.5A _M was met. In this experiment, P _A −P ₀ .
₅ is greater than 0.3, and P _A −P _{0.5 is} 3/4
(P _M - _{P 0.5} ). Experiment 44 (Carried out with A=3.0) The requirement AA _M was not met in this experiment for a feed with 2.40>A _M >2.24.

Claims (1)

[Claims] 1. Contains unbranched paraffins and contains C ₅ and
A gasoline fraction containing C ₆ hydrocarbons is contacted in the presence of hydrogen at elevated temperature and pressure with a fixed catalyst bed of a catalyst containing one or more noble metals of the Group on modernite as a support. In the method of increasing the octane number of light gasoline fractions, the content of _C5 paraffins is 10% by weight or more, _C6 paraffins is 10% by weight or more, and _C5 and _C6 paraffins are 90% by weight.
The hydrogen/feed molar ratio (A) depending on A _M as follows: a If A _M is less than 2.24, then A is at least
0.5 and at most 1.0, b If A _M is at least 2.24 and less than 2.40, then A is greater than 1.0, and A satisfies the relationship: A _M A2265·A _M ^-8.6 . And if c A _M is at least 2.40, then A is greater than 1.0, and A satisfies ^the following relationship: A _M A0.5A _M (where A _M =340・B ^0.4・C ⁴・(1-3D)/1+
Weight fraction of _C6 paraffins in the feed calculated for ^100C4B = _C5 + _C6 paraffins C=85-10.5・BE/22(1+B) D=C5 and _C6 in the feed contact with the catalyst at a temperature of 150 to 280 °C, applying the weight fraction of components other than C ₆ paraffins, and E = octane number of C ₅ + C ₆ paraffins in the feed. , a method for increasing the octane number of light gasoline fractions. 2. Process according to claim 1, characterized in that it is applied to a feed of a composition such that A _M is less than 2.24 and carried out at an A of less than 0.75. 3 Pressure from 3 to 50 bar, preferably from 10 to 40 bar and space velocity per kg of catalyst per hour.
3. A method according to claim 1, characterized in that it is carried out with 0.5 to 10 kg, preferably 1.0 to 5.0 kg. 4 using mordenite of the H type prepared by successive treatment of mordenite with an aqueous solution of an acid, preferably hydrochloric acid and with an aqueous solution of an ammonium compound, preferably ammonium nitrate, and optionally one or both of these treatments. The method according to any one of claims 1 to 3, characterized in that the steps are repeated once or several times. 5 Group precious metals or more from 0.01
5. Process according to any one of claims 1 to 4, characterized in that a catalyst containing 5% by weight, preferably 0.1 to 1.5% by weight is used. 6 From an aqueous solution in which the metal is present in the form of a cation,
Claims 1 to 5 characterized in that a catalyst is used which is prepared by loading a group noble metal onto mordenite from an ammoniacal solution in which the metal is preferably present in the form of a cationic complex.
The method described in any of the paragraphs.