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The effect of the tungsten oxide content in Pt/WO3-ZrO2 catalysts over the range of 10–35 wt.% on hydroisomerization of the heptanebenzene mixture (80/20, wt.%) was studied. The catalysts with the WO3 content of 15–25 wt.% were shown to have the highest fraction of the tetragonal zirconia phase (t-ZrO2, 87–96%), which allows achieving the highest yield of the sum of heptane isomers, particularly high-octane di- and trimethyl substituted isomers (DTMS), the yield of which reaches 69.4–76.7 and 24.5–27.9 wt.%, respectively. In the presence of such catalysts, the yield of methylcyclopentane is 52.1–61.3 wt.% at the 72.6–90.9 % selectivity of cyclohexane isomerization to methylcyclopentane.

The isomerization of n-heptane on BEA supported platinum catalysts with the addition of chlorine and fluorine as promoters was studied. The use of the halides decreased the operating temperature of the n-heptane conversion. The samples prepared at the stage of peptization showed an increase in the total conversion accompanied by a decrease in the yield of heptane isomers of 6 for chlorine and 27 wt.% for fluorine. Promotion by the halides at the stage of platinum application led to an increase in the catalyst activity without decrease in the selectivity values.

Textural characteristics, phase composition, and acidic properties of Pt/WO3/ZrO2 catalysts for C7-alkanes isomerization were studied. It was shown that the most active and selective catalysts are samples with WO3 content of 15–25 wt.% with a fraction of the active tetragonal phase of ZrO2 of 73–94 wt.%. It was found that an increase in the number of Bronsted acid sites contributes to an increase in the activity of tungstated zirconia catalysts in the isomerization of n-heptane.

Изомеризация парафиновых углеводородов является одним из важнейших процессов нефтеперерабатывающей промышленности, направленный на получение высокооктановых экологичных компонентов современных бензинов. Актуальным направлением в изомеризации является переработка фракции, содержащей С7-алканы. Обзор посвящен современным представлениям о закономерностях формирования активной поверхности вольфраматсодержащего диоксида циркония, который представляет собой высокоактивную каталитическую систему для реакции изомеризации гептанов. В обзоре рассматриваются вопросы по влиянию способа синтеза вольфраматсодержащего диоксида циркония, его химического состава, фазового строения и кислотных свойств на формирование активной поверхности систем WO3/ZrO2 и их каталитическую активность. Рассмотрена роль платины в каталитических системах WO3/ZrO2 для реакции изомеризации С7-алканов.

Comparative study of Pt-loaded tungstated zirconia and sulfated zirconia catalysts in the isomerization of n-heptane and n-hexane was carried out. According to the FTIR-spectroscopy of adsorbed pyridine, it was found that the Pt/SZ catalyst is characterized by the presence on the surface of stronger Lewis acid sites (a.b. 1448 cm−1) and Bronsted acid sites (a.b. 1543 cm−1) in comparison with the Pt/WZ catalyst (a.b. 1445 and 1538 cm-1, respectively). Moreover, the catalysts are characterized by a different distribution of acid sites: for Pt/SZ, the amount of LAS is five times higher than the number of BAS; for the Pt/WZ catalyst, on the contrary, the number of Bronsted sites exceeds the fraction of LAS by about two times. The difference between the tungstated and sulfated zirconia systems in terms of strength and the number of acid sites explains various regularities of C6-C7 alkane isomerization.

The paper shows the possibility of processing benzene and toluene containing a gasoline fraction obtained under conditions of fuzzy rectification of the reforming product in the process of hydroisomerization. The octane loss caused by the presence of toluene in the feed can be made up by saturating the product with butane. The Pt/Al2O3-BEA catalyst showed steady and stable operation in the resource tests on this fraction.

Isomerization of heptane, hexane and their mixture in the presence of Pt/WO3-ZrO2 catalysts was studied. The content of tungsten oxide in the catalysts was varied from 15 to 30 wt.%. It was shown that C6-C7 alkane hydrocarbons are efficiently isomerized in the presence of Pt-containing tungstated zirconia catalysts, both in the case of individual components (heptane and hexane) and their mixture (heptane/hexane=70/30 (wt.%)). Simultaneous isomerization of heptane and hexane over Pt/WO3-ZrO2 catalysts with the tungsten oxide content 15-20 wt.% at 220°C provided the conversion of heptane 91.4-91.5% and hexane 76.6-77.4% at the yield of stable catalyzate 79.3-82.2 wt.%. Therewith, the yields of high-octane dimethyl and trimethyl substituted isomers of heptane (DTMS) and isomers of hexane – dimethylbutanes (DMB) were 25.4-26.9 and 19.7-20.3 wt.% as referred to individual components (heptane and hexane, respectively).

The effect of aromatic hydrocarbons (benzene, toluene) on the isomerization of n-heptane over Pt/MOR/Al2O3 and Pt/WO3/ZrO2 catalysts is studied. It is shown that the presence of aromatic hydrocarbons results in a need to raise the reaction temperature by 20–30°C to achieve n-heptane conversion at the same level as for individual n-heptane. It is established that the yield of heptane isomers falls in 1.5 times (from 60.1 to 39.9 wt %) during the isomerization of n-heptane mixed with aromatic hydrocarbons over Pt/MOR/Al2O3 catalyst and remains at the same level (60.4–68.0 wt %) over Pt/WO3/ZrO2 catalyst. The developed catalysts can be used in industry to isomerize the C7 fraction separated from straight-run and catalytic reforming gasolines. The presence of aromatic hydrocarbons in feedstocks is undesirable when Pt/MOR/Al2O3 catalyst is used, as it reduces the yield of isomers.

The influence of aromatic hydrocarbons (benzene, toluene) on isomerization of n-heptane over Pt/MOR/Al 2 O 3 and Pt/WO 3 /ZrO 2 catalysts was studied. The presence of aromatic hydrocarbons was shown leads to the necessary temperature elevation by 20–30 °C in order to provide the conversion identical to that of individual n-heptane. In the mixture of n-heptane with aromatic hydrocarbons, the yield of heptanes isomers was established to be 1.5 times less (from 60.1 to 39.9 wt %) in the presence of Pt/MOR/Al 2 O 3 but to remain at the same level (60.4–68.0 wt %) in the presence of Pt/WO 3 /ZrO 2 . The developed catalysts can be used in industry for isomerization of C7 fraction isolated from straight-run gasoline and from catalytic reforming gasoline, the presence of aromatic hydrocarbons in the feedstock being undesirable.

Effect of cyclohexane and benzene on the isomerization of n-heptane on Pt/BEA-Al2O3 and Pt/MORAl2O3 catalysts was studied. In the presence of catalysts with platinum deposited from a [Pt(NH3)4]Cl2 solution, cyclohexane and benzene inhibit the conversion of n-heptane. At the same time, the presence of cycloalkanes and aromatic hydrocarbons leads to an increase in the isomerization selectivity due to the suppression of side reactions of hydrocracking. Samples based on the BEA zeolite were found to be more active as compared with similar samples based on mordenite.

Pt/BEA–Al2O3 catalysts for the hydroisomerization of benzene-containing gasoline fractions are studied using a model feedstock (20% benzene and 80% n-heptane). The catalysts are prepared by varying the zeolite content from 5 to 70 wt % at a constant Pt loading of 0.3 wt % in all samples, with an aqueous H2PtCl6 solution being used as the Pt precursor. The acid properties of the samples are studied by means of temperature-programmed desorption (TPD). The effect of the support’s zeolite/binder ratio on the activity of the catalysts is determined: an increase in the zeolite content raises the system’s acidity and shifts the range of the reaction toward lower temperatures. The optimum zeolite/binder ratio is found to be 30% BEA/70% Al2O3. Changing the SiO2/Al2O3 ratio of the zeolite from 25 to 40 is shown to have no noticeable effect on catalyst activity. The use of the catalysts supported on 30% BEA/70% Al2O3 in the hydroisomerization of benzenecontaining gasoline fractions can be recommended for improving environmental performance.

Isomerization of n-heptane and its mixture with methylcyclohexane (MCH) taken in a ratio of 2/1, 1/1 and 1/2 on the Pt/WO3/ZrO2 catalyst was studied. It was found that octane number of the catalyzate increases with the MCH content in the initial feed over the temperature range of 170-270 °C. The isomerization selectivity of n-heptane and the yield of isomers do not depend on the composition of the initial feed. The yield of C5+ catalyzate with a fixed octane number also increases with the MCH content in the feed.Isomerization of n-heptane and its mixture with methylcyclohexane (MCH) taken in a ratio of 2/1, 1/1 and 1/2 on the Pt/WO3/ZrO2 catalyst was studied. It was found that octane number of the catalyzate increases with the MCH content in the initial feed over the temperature range of 170-270 °C. The isomerization selectivity of n-heptane and the yield of isomers do not depend on the composition of the initial feed. The yield of C5+ catalyzate with a fixed octane number also increases with the MCH content in the feed.

The effect of fluorine additives (1.5–3 wt.%) in Pt/WO3−ZrO2−Al2O3 catalysts on n−hexane isomerization was studied. The best performance was obtained in the presence of catalyst with the fluorine content 2.5 wt.% at 240°C: conversion – 80.0 %, selectivity – 88.5%, yield of stable catalyzate – 93.2 wt.%, yield of the sum of hexane isomers – 70.8 wt.%, and yield of high-octane dimethylbutanes (DMB) – 16.1 wt.%. Fluorine additives were shown to change the unit cell parameter a of tetragonal zirconia due to the substitution of oxygen atoms by fluorine atoms.The effect of fluorine additives (1.5–3 wt.%) in Pt/WO3−ZrO2−Al2O3 catalysts on n−hexane isomerization was studied. The best performance was obtained in the presence of catalyst with the fluorine content 2.5 wt.% at 240°C: conversion – 80.0 %, selectivity – 88.5%, yield of stable catalyzate – 93.2 wt.%, yield of the sum of hexane isomers – 70.8 wt.%, and yield of high-octane dimethylbutanes (DMB) – 16.1 wt.%. Fluorine additives were shown to change the unit cell parameter a of tetragonal zirconia due to the substitution of oxygen atoms by fluorine atoms.

Hydroisomerization of a benzene/heptane mixture over platinum catalysts supported on BEA zeolite with alumina addition was studied. The catalyst activation conditions – temperatures of its oxidative calcination and reduction with hydrogen as well as the conditions of hydroisomerization reaction were examined. It was shown that the catalyst should be reduced in flowing hydrogen at 350°C without precalcination in an air flow. The operating temperature of the process and the catalyst selectivity to target products can be controlled by varying the liquid hourly space velocity. A decrease in the H2/feed ratio to 1/1 mol/mol leads to a substantial drop in the yield of heptanes with isomeric structure and methylcyclopentane.

The paper deals with the modifying effect of tin, iron and manganese, which are introduced at different stages of the synthesis, on the reaction of n-hexane isomerization in the presence of supported Pt/SZ/Al2O3 catalysts. The addition of a modifier was shown to affect the catalytic performance in isomerization reaction. The activity of modified catalysts increases due to redistribution of Broensted and Lewis acid sites with the preferential increase in the LAS content. The deposition of iron and manganese on alumina or the introduction of tin, iron and manganese in aluminum hydroxide increases the yield of the sum of hexane isomers to 80-85 wt.%, and the yield of the sum of dimethylsubstituted isomers to 28-33 wt.%.

Stability of the Pt/Al2O3-BEA catalyst in hydroisomerization of the model heptane/benzene mixture was studied. It was shown that the investigated system is highly stable and does not deactivate for 53 hours of operation, retaining its acidic characteristics and pore structure.

The effect of the mordenite acidic modulus (SiO2/Al2O3, 20 and 30) of Pt/MOR/Al2O3 catalysts on the heptane isomerization reaction is investigated. The content of zeolite in the catalysts is varied from 10 to 50 wt %, with platinum applied to the samples from solutions of different precursors: H2PtCl6 and [Pt(NH3)4]Cl2. It is established via the TPD of ammonia and FTIR spectroscopy (the adsorption of NH3 and СО) that the total acidity of zeolite falls as the modulus grows: the number of Bronsted (BAC) and Lewis (LAC) acidic sites is reduced, accompanied by an increase in the strength of their acidity. The catalysts are tested in the n-heptane isomerization reaction. It is shown that the selectivity of n-heptane isomerization falls substantially when the acidic mordenite modulus is increased from 20 to 30.

The effect of concentration of the metallic component – platinum (0.1-2 wt.%) – and its electronic state in Pt/WO3/ZrO2 catalysts on characteristics of n-heptane isomerization was studied. It was found that a rise in the platinum concentration to 1.5 wt.% increases the yield of the target products of n-heptane isomerization – high-octane di- and trimethyl-substituted isomers (DTMS). Calcination of the catalyst in flowing air was shown to facilitate the formation of charged platinum, the presence of which enhances the catalyst activity.

Isomerization of n-heptane over platinum catalysts supported on Y, BEA, MOR and ZSM-5 zeolites with different SiO2/Al2O3 ratio in a mixture with alumina was studied. A platinum precursor was represented by aqueous solutions of H2PtCl6 and [Pt(NH3)4]Cl2. The use of hexachloroplatinic acid was shown to increase selectivity of the reaction. Samples containing Y and BEA zeolites demonstrated the highest selectivity and yields of the target products – di- and trimethyl- substituted heptane isomers.

The effect of Pt and Pd concentration in WO3/ZrO2 catalysts on their acidic and catalytic properties in isomerization of n-heptane has been studied. It was found that the highest yield of the target products of the reaction – di- and trimethyl substituted (DTMS) high-octane heptane isomers – is reached on the samples with the platinum content of 1.0–1.5 wt.% and is equal to 29.2–29.3 wt.%. When Pd is used as a metallic component, the DTMS yield of ca. 29.1 wt.% is attained at a palladium content of 0.1 wt.%. Pt(Pd)/WO3/ZrO2 catalysts were subjected to thermal treatment in a hydrogen medium and effect of the treatment conditions on isomerization of n-heptane was investigated. The reduction of the catalysts at temperatures above 300°C was shown to reduce tungsten atoms with the formation of Lewis acid sites (LAS), thus promoting the side reactions leading to cracking of heptanes.

The modifying effect of tin introduced at different steps from various tin precursors on characteristics of n-hexane isomerization in the presence of supported Pt/SZ/Al2O3(Sn) catalysts was studied. The addition of Sn was shown to substantially affect the porosity characteristics of the catalysts and dispersion (particle size) of the active phase of tetragonal zirconia. The use of Sn(IV) hydroxide as an additive to the initial aluminum hydroxide allowed obtaining the supported catalyst with the particle size of the t-ZrO2 active component 3.2 nm and specific surface area of zirconia 294 m2/g. At a zirconia content of ca. 20 wt.% the catalytic performance of the catalyst in n-hexane isomerization approached the performance of the bulk samples in which ZrO2 content attained 70-75 wt.%.The modifying effect of tin introduced at different steps from various tin precursors on characteristics of n-hexane isomerization in the presence of supported Pt/SZ/Al2O3(Sn) catalysts was studied. The addition of Sn was shown to substantially affect the porosity characteristics of the catalysts and dispersion (particle size) of the active phase of tetragonal zirconia. The use of Sn(IV) hydroxide as an additive to the initial aluminum hydroxide allowed obtaining the supported catalyst with the particle size of the t-ZrO2 active component 3.2 nm and specific surface area of zirconia 294 m2/g. At a zirconia content of ca. 20 wt.% the catalytic performance of the catalyst in n-hexane isomerization approached the performance of the bulk samples in which ZrO2 content attained 70-75 wt.%.

Supported Pt/SZ/Al2O3 catalysts prepared via the thermolysis of zirconium sulfate in support pores are studied. The content of the active component (sulfated zirconia) in the catalysts is 25–30 wt %, 2–2.5 times lower than in massive catalysts equivalent in their catalytic characteristics. Tests in the isomerization of n-hexane are performed. It is shown that the total yields of 2,2- and 2,3-dimethylbutanes (DMB) on the supported catalysts at temperatures of 140–160°C are 34–36 wt % at a stable C5+ catalyzate yield of 96–98 wt %, comparable to the results obtained on industrial isomerization catalysts based on sulfated zirconia. The results indicate that the supported Pt/SZ/Al2O3 catalysts can be used in the isomerization of C5-C6 fractions to synthesize environmentally friendly high-octane gasoline components.

Researches of catalysts Pt/WO 3 /ZrO 2 (Pt content is 1 wt.%) at varying WO 3 concentrations (10-35% wt.) are carried out in the isomerization reaction of n-heptane, under the following conditions: temperature range is 140-220°C, pressure is 1.5 MPa, the ratio H 2 /n-heptane is 3 (mol.), heptane volume velocity is 1h-1. X-ray analysis, N 2 adsorption-desorption, infrared spectroscopy, temperature-programmed desorption of ammonia are used to characterize the physical and chemical properties of the prepared catalysts, atomic emission spectrometry with inductively coupled plasma is for WO 3 analysis. Maximum catalysts activity and selectivity in the isomerization reaction of n-heptane is obtained at the reaction temperature of 170°C on the catalyst with a content of 25% wt WO 3 .: conversion of n-heptane is 84%, the selectivity to the heptane isomers sum is 71.9%, dimethyl and trimethyl heptane isomers yield is 22.8% wt.

The effect of zirconia precursor in Pt-containing WO3/ZrO2 catalysts on isomerization of n-heptane was studied. Samples synthesized with zirconium sulfate as a ZrO2 precursor were shown to be more ...

Pt/MOR/Al2O3 catalysts with mordenite zeolite contents of 10 to 50 wt % are prepared. Solutions of H2PtCl6 and [Pt(NH3)4]Cl2 are used as precursors of Pt. It is shown by means of transmission electron microscopy (TEM) that the localization of platinum on a MOR/Al2O3 mixed support depends directly on the nature of the metal’s precursor. The catalysts are tested in the isomerization of n-heptane. It is shown that the best samples of catalysts provide yields of the target products (dimethyl and trimethyl substituted isomers of heptanes) on the level of 21 wt % at a temperature of 280°C, while those of a C5+ stable catalyzate are on the level of 79–82 wt %. The catalysts can be used to improve the environmental friendliness of gasolines by employing them in the isomerization of the 70–105°C fraction of directly distilled gasoline.

Samples of SO4/ZrO2/Al2O3 and Pt/Al2O3 Pt/Al2O3 catalysts and their physical mixtures are prepared, and the catalytic properties of the samples in n-hexane isomerization are studied. The considerable effect of the state of platinum on the catalytic performance of the samples is revealed. IR spectroscopy (COads), oxygen chemisorption, and oxygen-hydrogen titration show that the reduced catalysts contain ionic forms of platinum capable of adsorbing up to three hydrogen atoms per each surface atom of platinum. By means of H/D isotopic exchange, it is found that specific properties of ionic platinum are apparent in the formation of the hydride form of adsorbed hydrogen. It is speculated that the activity and stability of catalysts based on sulfated zirconia in n-hexane isomerization can be attributed to the involvement of ionic and metallic platinum in the activation of hydrogen. The results can be used to develop effective catalysts for the isomerization of C5–C6 gasoline fractions in order to obtain the isomerizate as a high-octane additive for modern gasolines.

New reforming catalysts PR-81 and SPR-81, which differ from their predecessors (PR-51 and PR-71) in enhanced mechanical strength (1.8–2.0 versus 1.2–1.5 kg/mm), are developed and brought into industrial-scale production by Institute of Problems of Hydrocarbons Processing, Siberian Branch, Russian Academy of Sciences. Four batches of catalysts with a total weight of 78 t are produced at JSC Angarsk Catalysts and Organic Synthesis Works Rosneft Oil Company for three industrial reformers operating in the gasoline and aromatic modes at Purnefteperarabotka LLC, OJSC Gazprom Neftekhim Salavat, and the JSC Gazprom Neft-Omsk Refinery. A comparative analysis of the performance of new catalysts and their predecessors is performed. It is shown that PR-81A catalyst, used in an LP-35-11/40 reformer over the period 2010–2013, is characterized by enhanced activity (the temperature of attaining the required process severity is 25–30°C lower than that of PR-71); here, the yield of the stable reformate was 2–3 wt % higher and the content of aromatic hydrocarbons was 5 wt % lower. The combined loading of an L-35-11/600 reformer with catalysts PR-81A/SPR-81 allowed the production of a gasoline component with a research octane number (RON) of 95–97 even with the poor quality of the raw material and operating conditions. Our results lead us to expect the large-scale use of the new catalysts at refineries in Russia, the CIS, and the Baltic countries.

Benzene hydroisomerization is among the promising processes converting benzene into methylcyclopentane (MCP), which is an environmentally friendlier, octane boosting component of motor fuels. Benzene hydroisomerization into MCP over the Pt/MOR/Al2O3 (MOR = mordenite) catalytic system is reported here. The dependence of the yield of the target product on the acidic properties of the support and platinum precursor ([Pt(NH3)4]Cl2 or H2PtCl6) have been investigated in order to optimize the catalyst composition. The acidic properties of the surface have been altered by introducing 30–95 wt % alumina into the support. Catalytic activity has been measured in the hydroisomerization of cyclohexane and a benzene (20 wt %) + n-heptane (80 wt %) mixture in a flow reactor at 250–350°C, 1.5 MPa, H2: CH = 3: 1, a cyclohexane LHSV of 6 h−1, a mixed feedstock LHSV of 2 h−1, a catalyst bed volume of 2 cm3, and catalyst pellet sizes of 0.25–0.75 mm. The most efficient catalyst for cyclohexane and n-heptane isomerization and benzene hydroisomerization is the platinum-containing catalyst (0.3 wt % Pt) whose support consists of 30 wt % MOR and 70 wt % Al2O3. The highest yield of the target products of isomerization in the presence of this catalyst is attained in the temperature range from 280 to 310°C, which is thermodynamically favorable for MCP formation from benzene. This indicates that this catalyst is promising for the hydroisomerization of benzene-containing gasoline fractions. Use of H2PtCl6, a readily available chemical, as the platinum precursor is favorable for commercialization of the catalyst and ensures price attractiveness in its industrial-scale manufacturing.

Supported platinum catalysts based on ferrierite type zeolite with Pt content in the range of 1.3–2.8 wt % are prepared. The localization of Pt in zeolite channels is studied for the first time. It is shown that the platinum localized in them increases the yield of products from the selective hydrocracking of n-hexane. Platinum on the outer surface of the zeolite crystals participates in the transformation of n-hexane in the direction of forming hydrocarbons with isomeric structure. The catalysts can be used to improve the octane rating of reformed gasoline, owing to the selective removal of low-octane n-paraffin hydrocarbons and the increase of the portion of high-octane isoparaffin hydrocarbons in the catalytic reforming gasolines.

The state of surface Pt atoms in the Pt/SO4/ZrO2/Al2O3 catalyst and the effect of the state of platinum on its adsorption and catalytic properties in the reaction of n-hexane isomerization were studied. The Pt-X/Al2O3 alumina-platinum catalysts modified with various halogens (X = Br, Cl, and F) and their mechanical mixtures with the SO4/ZrO2/Al2O3 superacid catalyst were used in this study. With the use of IR spectroscopy (COads), oxygen chemisorption, and oxygen-hydrogen titration, it was found that ionic platinum species were present on the reduced form of the catalysts. These species can adsorb to three hydrogen atoms per each surface platinum atom. The specific properties of ionic platinum manifested themselves in the formation of a hydride form of adsorbed hydrogen. It is believed that the catalytic activity and operational stability of the superacid system based on sulfated zirconium dioxide were due to the participation of ionic and metallic platinum in the activation of hydrogen for the reaction of n-hexane isomerization.

The catalytic properties of model Pt/SiO2 and Pt/Al2O3 catalysts and their physical mixtures with SO4/ZrO2 in the reaction of n-hexane isomerization have been studied. Significant effects of the influence of the platinum state on the characteristics of isomerization on the catalysts and their physical mixtures with SO4/ZrO2 have been revealed. The observed changes in catalytic performance of the mixed catalysts have been explained from the position of a bifunctional mechanism with the participation of ionic platinum promoting the formation of hydride ions, which play an important role in the activation of transformations of intermediates in isomerization reactions.

The industrial operation experience of Russian PR reforming catalysts in Russian and Ukrainian refineries was summarized. The comparative industrial application efficiency analysis of developed PR reforming catalysts and their imported analogues was provided for different refineries. For the first time, the results showed the higher efficiency of the PR-71 catalyst used in radial reactors with alternated raw gas flow direction.

Modern models of the state of disperse platinum in low-percentage industrial catalysts for production of motor fuels (reforming catalysts) are considered. The state of surface platinum atoms was assessed by means of an original approach based on division of surface centers on metallic (Pt0) and ionic platinum (Ptσ). Physical and chemical properties of specific Pt0 and Ptσ centers and their role in basic catalytic reforming reactions are discussed.

Analysis of the modern state of catalytic reforming is performed. Comparative assessment of the efficiency of various technologies of the process is given and their distribution in Russia and abroad is shown. Experience of the modernization of reforming installations with periodic catalyst regeneration is summarized. The state of manufacture of reforming catalysts in our country and accumulated experience of the development of catalysts of the PR series are presented. Results of industrial exploitation of new domestic reforming catalysts are shown. On this basis comparative assessment of Russian and imported catalysts is given.

In 1977-1979, Ryazan' Oil Refinery was the first in the industry to convert all reforming units to KR-102, KR-104, and KR-106 polymetallic catalysts. The individual stages of the process were perfected, which allowed improving the technical and economic indexes of operation of the units in comparison to the indexes for the monometallic AP-64 catalyst [1–3]. KR-108 and KR-110 catalysts, primarily distinguished by high selectivity, were used in three reforming units in 1982-1983 [4]. These catalysts were the most widely used in the industry and were successfully used to the beginning of the 1990s [5].

Behavior of supported Pt in O2 chemisorption and (O2−H2) titration has been studied. In Pt/SiO2, Pt/α-Al2O3 and Pt/γ-Al2O3 Pto catalysts are characterized by the following stoichiometric coefficients of oxygen adsorption (X), hydrogen adsorption (Y) and oxygen-hydrogen titration (Z) X:Y:Z=1:1:1.5. The co-efficients differ for Pt−Cl/γ-Al2O3 reforming catalysts. This is explained by the presence of electron deficient platium (Ptσ) with a coefficient ratio of X:Y:Z=0.5:2:1.5.

Particular properties of metal (Pto) and electron deficient (Ptσ) platinum have been investigated by chemisorption and IR methods. Data about thermostability to sintering in hydrogen and to oxidizability are reported.

The paper presents the results of the carrier acidity impact studying on the Pt-Re/Al 2 O 3 catalytic properties in gasoline reforming. The Pt-Re/Al 2 O 3 catalyst preparation based on the superacidity carrier in consequence of the presence of promotor - the bayerite phase of aluminum hydroxide resulted in the H-C 7 predominat cracking to C 3 -C 6 light paraffins. The obtained catalyst allows to produce the reduced aromatics content reformed gasoline (55%wt).