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Collaborating Authors
7th World Petroleum Congress
Abstract In the last fifteen years, by-product gasolines produced by thermal cracking to make light olefins have been an attractive source of aromatics and high octane number motor fuel. For motor fuel production, only the contained diolefins need be hydrogenated, When aromatics are the desired product, complete desulfurization, denitrification and olefin saturation are required, generally necessitating at least two stages. The contained diolefins are hydrogenated in the first stage so that the material may be further heated and completely hydrotreated in following stages. Recent developments, both engineering and catalytic, have brought changes in processing technology which will be discussed. INTRODUCTION Résumé Au cours des quinze dernières années, les essences apparaissant comme sous-produits de la fabrication par craquage thermique des oléfines légères ont été une source intéressante d'aromatiques et de carburants à haut indice d'octane. Pour la production des carburants, il suffit d'hydrogéner les dioléfines. Pour obtenir les aromatiques il faut en outre réaliser une désulfuration, une dénitrification et la saturation des oléfines ce qui demande généralement deux phases de traitement. La première phase consiste à hydrogéner les dioléfines et préparer les phases suivantes ou la charge est portée à température plus élevée et soumise à une hydrogénation complète. On expose les progrès de la technologie de fabrication résultants des derniers développements à la fois dans le domaine des méthodes d'application et en matière de catalyseurs. The production of ethylene has experienced an enormous growth during the past 15 years. In billions of pounds per year, ethylene production outside the East-Bloc countries has increased from 1.5 in 1950 to 3-0 in 1956l and to 12 in 1965; present predictions are 29 billion pounds by 197019. These values are shown in Table I. In the United States the principal charge stocks are ethane and propane while outside the U.S. the usual charge stock is naphtha. In addition to ethylene, many by-products are formed. Some typical pyrolysis products and yields are shown in Table I120. Ethane gives the highest yield of ethylene (82 % wt) and the lowest yield of by-product gasoline (2% wt). Propane gives an intermediate yield of ethylene (44 % wt) and five times as much gasoline as does ethane. Yields from naphtha depend upon the paraffin, naphthene and aromatic contents, as well as severity of cracking, but yields from a typical naphtha are 32% wt ethylene and 22 % wt by-product gasoline. On a billion pound of ethylene per year basis, 35,000 bd of propane or 32,800 bd of naphtha are required. The difference in by CHARLES H. WATKINS, Universal Oil Products Company, Des Plaines, Illinois, U. S. A. TABLE I ETHYLENE CAPACITY BiIlions pounds per year from: Ethane-propane*
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During the previous congress at Frankfurt considerable attention was devoted to hydrogenation processes. The discussions in Panel No. 7 of the Frankfurt Congress then comprised both hydrorefining processes-i.e. procedures aiming at quality improvement of petroleum fractions as such-and conversion processes, of which hydrocracking is the most important representative. The decision to organize the present congress in panel discussions of a more limited scope immediately posed the problem how to deal with the vast area of hydrogenation processes, which also embraced such procedures as the production of naphthenes from the corresponding aromatic hydrocarbons. After consultation of all parties concerned it was decided to concentrate into the Panel the processes in which no major destruction of hydrocarbons takes place. The contributions on hydrocracking and catalytic reforming are incorporated in the previous Panel called "Advances in Conversion Processes in Refining". It was further agreed that such processes as hydrogenation of aromatics would be dealt with under the aegis of the Panel for Hydrotreating. In close and frequent consultation with your Vice-Chairmen, I have tried to cover the field of this panel by inviting survey papers on six important types of application. The reaction of the organizations/individuals invited was generally favourable and we are confident to have found authors well qualified for the task envisaged. The following general principles for the preparation of the papers were suggested:The paper should adequately cover contributions not only of the authors' company or organization, but also contributions of others. Recent scientific and/or engineering developments should be emphasized. In view of competitive aspects, process economics are to be discussed only in the broadest sense. I believe that these principles should also guide the following discussions. In addition to the survey papers invited, a contribution was submitted dealing with the kinetics of distillate desulphurization. It was found difficult to incorporate its contents into the relevant survey paper and therefore, it is presented separately as an individual paper. Further it was decided to discuss the papers in two sessions, one dealing with processes in which desulphurization plays the major role, the other containing a group of papers discussing the application of hydrogenation for rather varied purposes. Accordingly the papers were presented as follows :Advances in desulphurization of distillates, by P. Docksey and R. J. H. Gilbert. Advances in desulphurization of residual fractions and asphalts, by W. F. Arey, Jr., N. E. Blackwell, III and A. D. Reichle. Kinetics of high-sulphur distillate hydrotreating, by R. M. Massagutov, G. A. Berg, G. M
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Résumé PROGRES REALISES DANS L'HYDROGENATION DES HYDROCARBURES AROMATIQUES La première partie de cet article traite de l'hydrogénation des hydrocarbures aromatiques purs en phase liquide sur catalyseurs pulvérulents au Nickel. Les données de base permettant d'optimiser ce type d'opération y sont exposées: données thermodynamiques, données cinétiques, influence des impuretés dont l'oxyde de carbone, l'eau et le thiophène, influence de la nature du catalyseur. La deuxième partie relate les derniers résultats obtenus dans l'hydrogénation des aromatiques contenus dans les distillats légers ou moyens en vue d'améliorer leur point de fumée. Les résultats présentés montrent qu'à température élevée sur catalyseurs à base de sulfures métalliques des groupes VI A et VI11 de la classification périodique, il n'est pas suffisant d'avoir une bonne activité hydrogénante mais qu'il faut également que le catalyseur puisse isomériser les cyclanes de la charge pour déplacer l'équilibre thermodynamique de l'hydrogénation. D'autres résultats montrent qu'une deuxième façon d'éviter ce frein thermodynamique consiste à hydrogéner à basse température sur métaux du groupe VI11 (Nickel ou Platine) des charges préalablement désulfurées, de façon plus ou moins poussée, suivant le catalyseur que l'on envisage d'utiliser dans l'hydrogénation subséquente. Abstract The first part of this paper deals with hydrogenation of pure aromatic hydrocarbons in liquid phase with powdered nickel catalysts. Basic data permitting optimization of this type of operation are given as: thermodynamic data, kinetic data, effect of impurities such as carbon monoxide, water and thiophene; influence of catalyst type. The second part refers to the latest results obtained in hydrogenation of aromatic hydrocarbons contained in light or middle distillates in order to improve their smoke-point. The results show that at higher temperatures and with catalysts based on metallic Sulfides of groups VI A and VI11 of the periodic table, a good hydrogenation activity is not sufficient; it is also necessary that the catalyst should isomerize the cycloparaffins of the feed in order to displace the thermodynamic equilibrium of the hydrogenation reaction. Another way to avoid this thermodynamic limitation consists in realizing hydrogenation at low temperatures with metal catalysts such as nickel or platinum. In this case, the feed has to be desulphurized more or less severely depending on the catalyst used in the hydrogenation step. Durant les quatre dernières années, de nombreux articles ont été publiés concernant l'hydrogénation des aromatiques mono ou polynucléaires; ces divers articles sont généralement très spécialisés et ne traitent qu'un point particulier du processus d'hydrogénation: études de chimisorption, études de cinétique, études de mécanismes, études, des modes
- Materials > Chemicals > Specialty Chemicals (1.00)
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Kinetics of High-Sulphur Distillate Hydrotreating
Massagutov, R. M. (Bashkirian Scientific Research Institute of Petroleum Refining BashNII NP, U.S.S.R.) | Berg, G. A. (Bashkirian Scientific Research Institute of Petroleum Refining BashNII NP, U.S.S.R.) | Kulinich, G. M. (Bashkirian Scientific Research Institute of Petroleum Refining BashNII NP, U.S.S.R.) | Kirillov, T. S. (Bashkirian Scientific Research Institute of Petroleum Refining BashNII NP, U.S.S.R.)
Abstract Résumé Hydrogenation processes are in general use for processing high-sulphur crude oils and petroleum products, oil refiners experience serious difficulties when producing marketable products from the above feed stocks without employment of these processes. In spite of the considerable value of hydrotreating processes, few investigations devoted to kinetic studies of the petroleum product hydrodesulphurization were available up to now. In the present report are given the results of tests checking the applicability of available kinetic equations for describing the authors' experimental data on hydrodesulphurization of several high-sulphur petroleum distillates. It is the interdependence of changes of some hydrogenate properties (density, sulphur, and metal content, coking capacity, etc.) which is shown. The established mathematical correlations describe with sufficient accuracy the reported experimental data of the authors as well as of other investigators obtained under operating conditions varying over a wide range. Dans le traitement des pétroles et des produits pétroliers riches en soufre les procédés d'hydrogénation sont en usage extensif. La production de produits marchands à partir des charges ci-dessus est très difficile sans l'emploi de ces procédés. Malgré que des procédés d'hydrotraitement sont de haute importance, il y a peu d'investigations consacrées à l'analyse cinétique de l'hydrodésulfuration des produits pétroliers. Le rapport présente des résultats obtenus par l'étude de I'applicabilité de certaines équations cinétiques pour la description des données expérimentales des auteurs sur l'hydrodésulfuration de certains distillats riches en soufre. On a montré l'interdépendance de certaines propriétés d'un produit obtenu par hydrogénation (densité, teneur en soufre, métaux, capacité de cokéfaction, etc.). Les correlations mathématiques établies décrivent avec une précision satisfaisante les données expérimentales obtenues par les auteurs ainsi que par les autres investigateurs en régimes variables dans une large région. INTRODUCTION In recent years the hydrocracking and hydrotreating processes for heavy petroleum distillate fractions have been under extensive development. To obtain better results when introducing them commercially, it is essential therefore to know as much as possible about the regularities of these processes. A major part of available investigations have been devoted to studying process variables influence on process results, to testing new catalysts, and developing process technology. We think however that too little consideration has been given to a kinetic study of hydrodesulphurization, to the establishment of mathematical correlations to show petroleum distillate properties versus operating conditions, and to the interdependence of changes of various properties variables. These data
Abstract Résumé The rate of growth of hydrotreatment of catalytic cracking feedstocks appears to be increasing. In part, this may be due to the ability to analyze catalytic cracking feedstocks in more detail and hence determine more precisely the need for and value of hydrogenation. The newer hydrotreating catalysts result in higher hydrogen consumption and, when consideration is given to the kinetics and thermodynamic equilibria of the system, it is possible to operate in a manner such that the hydrogen is used to convert selectively those components most deleterious to catalytic cracking and to produce those which yield the most desirable components from catalytic cracking. The Aromatics Formation Reaction, a phenomenon in catalytic cracking, accentuated by hydrotreatment of catalytic cracking feed, undoes some of the potential benefit of hydrotreatment of catalytic cracking feed. The new zeolitic cracking catalysts are, somewhat surprisingly, very responsive to hydrotreatment of catalytic cracker feed. Both conversion and gasoline yield show greater improvement with depth of hydrogenation using zeolitic catalysts than when using conventional amorphous catalytic cracking catalysts. L'application de l'hydrotraitement aux charges de craquage catalytique est discutée en fonction des divers aspects de la chimie de chacun des deux procédés. L'opération d'hydrotraitement peut être conduite de manière à détruire les composés les plus nuisibles pour le craquage catalytique et à obtenir les produits les plus désirables. Les considérations d'équilibre et de ciné- tique sont ensuite commentées pour le traitement par hydrogénation et pour le craquage catalytique. Considering that both catalytic cracking and hydrotreating are well-established processes, it must be considered remarkable that the hydrotreating of catalytic cracker feed has not shown until recently much sign of being applied on a substantial scale. From the data' shown below, one observes that through 1964 catalytic cracker feed hydrotreating represented only about 1 % of the installed hydrotreating capacity in the United States but as of 1966 it has grown to about 5 %: in these statistics since some hydrotreatment of feed to catalytic cracking comes about in units designated differently (e.g., the first section of a hydrocracker*. The reasons for the slow initial growth are not entirely clear since the process has been described in a laudatory fashion many times during the past ten years3, 4, 5, 6. The more rapid rate of growth of catalytic cracker feed hydrotreating in the last few years may be attributable to the development of new and improved hydrotreating Year 1967 1963 1964 1965 1966 (Estimated) Cat. Cracker Feed Hydrotreating, bbl/D. .. ... 16,300 26,800 95,300 111,100 186,100 Total U.S. Hydrotreating Capacity. .. .. ... 2,536,690 2,748,930 2,929,465
- Energy > Oil & Gas > Downstream (1.00)
- Materials > Chemicals > Commodity Chemicals > Petrochemicals (0.37)
Abstract ADVANCES IN THE HYDROGEN TREATING OF LUBRICATING OILS AND WAXES The present status of the use of hydrogen treating in the manufacture of lubricating oils and waxes is described giving particular emphasis to the advances made since the previous World Petroleum Congress in 1963. Two types of hydrogen treating processes, hydrofinishing and hydrotreating, are distinguished. These operations differ essentially in severity and in application. Hydrofinishing processes employ relatively mild conditions and are widely used in place of conventional mild acid and/or clay treating techniques for improving the quality of both untreated and solvent refined lubricating oils and waxes. Hydrotreating processes involve more severe hydrogenation conditions which enable high quality lubricating oils to be produced without the need for prior solvent extraction. High viscosity index oils may also be obtained by hydrotreating under conditions which favour hydrocracking as well as hydrogenation. Recent data are presented to illustrate the effect of hydrofinishing and hydrotreating on product quality and comparison is made with products refined by conventional methods. Investment and manufacturing costs for hydrogen treating are also considered. Although numerous catalysts are suitable for the hydrogen treatment of lubricating oils and waxes, cobalt molybdate and nickel tungsten sulphide catalysts are the most widely used. Résumé Une description de l'usage courant du raffinage à l'hydrogène des huiles lubrifiantes et des cires minérales est l'objet de cette communication. On fait surtout ressortir le progrès effectué depuis le Congrès Mondial du Pétrole en 1963. On distingue deux types de raffinage à l'hydrogéne; l'hydrofinissage et l'hydrotraitement. Ces deux procédés diffèrent essentiellement par les conditions operátoires et par l'application. Les procédés d'hydrofinissage emploient des conditions relativement peu rigoureuses. Ils remplacent fréquemment les techniques conventionnelles de traitement à l'acide dilué et à terre absorbante pour améliorer la qualité des huiles lubrifiantes et des cires préalablement traitées au solvant ou non. Les procédés d'hydrotraitement impliquent des conditions plus rigoureuses d'hydrogénation qui produisent des huiles lubrifiantes de haute qualité sans avoir recours à une extraction au solvant préalable. On peut aussi obtenir des huiles d'indice de viscosité élevé par l'hydrotraitement sous des conditions qui favorisent l'hydrocraquage aussi bien que l'hydrogénation. Des données récentes sont présentées pour illustrer l'effet de I'hydrofinissage et de l'hydrotraitement sur la qualité des produits. Une comparaison est faite avec des produits raffinés par des méthodes conventionnelles. Des coûts de construction et d'opération d'usine pour le raffinage à l'hydrogéne sont aussi considérés. Le molybdate
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Dr. RAWLINGS: Can the more expensive zeolite catalysts be justified when operating at a moderate conversion of, say, 60%? Have there been any recent advances in chemical systems for removing metal contaminants from catalysts? Mr. SMITH: The zeolites are more difficult to justify at the lower conversions. There are no new developments for the chemical removal of metals fromcatalysts. Mr. SCOTT: What is the relative performance of the zeolite catalysts with high boiling feedstocks ? Is there any evidence that the zeolitic catalysts have an increased tolerance for metal contaminants ? Mr. SMITH: The zeolitic catalysts differ from conventional catalysts less as the feed boiling point and aromaticity increases. There is no real information whether zeolites have an increased tolerance to metal contaminants. Dr. W. A. BAILEY (Shell Oil Co.): There is reason to believe that many large fluid cracking units are more severe with respect to catalyst deactivation than are smaller units. If so, what are the major factors responsible for this difference? Mr. SMITH: Larger units are not necessarily harder on catalysts if the type of operation is comparable; however, if there is a difference, this could be brought about by local overheating of the catalyst caused by less uniform contacting of the feedstock with the regenerated catalyst andlor poorer distribution of the air in the regenerator. Dr. B. AMERICK (U.S.S.R.): Can you say some more about the role of hydrogenation, deasphalting, solvent extraction, coking and vacuum distillation for improving cracking feed stock quality ? What proportion of catalytic cracking installations uses feed stocks improved by hydrogenation, deasphalting and other processes ? Mr. SMITH: Most installations use some form of feedstock treatment. All the processes except the first are in common use. Hydrogenation is less widely used. Moving bed catalytic cracking Mr. VAN'T SPIJKER: No mention is made in the paper of how much catalyst activity is reduced by the "Treat0 Process". Mr. SCOTT: There is essentially no effect on catalyst performance, including catalyst activity. Mr. SMITH: Are the activity advantages of Durabead 6 over Durabead 5 maintained when using additives for effectively reducing abrasion and!or erosion ? Is less additive required than with the older Durabead 5? Mr. EASTWOOD: The additive seems to be about the same for both catalysts. Dr. F. G. CIAPETTA (W. R. Grace & Co.): I would be interested in comments on what has been observed on commercial equilibrium recycle operation concerning the difference in product yields when using Durabead 6 in place of Durabead 5. Also do these two catalysts show the same response to differences in feed stock properties such as increased boiling point, increased aromatic conte
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Abstract Résumé Hydrodesulfurization has been extensively used with lighter, more easily desulfurized petroleum fractions. Application to heavy, residual feeds has been deterred by the unique characteristics of such feeds and the resultant more severe and costly processing requirements. The two major characteristics of residua which distinguish them from distillates are that residua contain1 asphaltenes and other high molecular weight, aromatic structures which severely inhibit the rate of desulfurization by hydrotreating, and2 ash forming constituents such as metallo-organic compounds which result in catalyst contamination and interfere with catalyst regeneration. Investigations of various reactor systems have been in progress for some time. Both fixed and fluidized or ebullating catalyst beds have been developed for use in residuum hydrodesulfurization. Diffusional effects continue to be a subject of investigation. They are felt to be an important but somewhat imponderable factor which has not readily lent itself to quantitative assessment. Residuum desulfurization is generally treated as a first order or pseudo second order reaction with respect to sulfur. Simultaneous first order expressions for two sulfur species which exhibit different reaction rates may be a preferred treatment. Improved catalysts and catalyst modifications are being developed. Specially prepared alumina bases have been found to have superior characteristics with respect to both activity and activity maintenance. Colloidal dispersions of hydrodesulfurization catalysts has been found to be effective with asphaltene containing oils. Les procédés d'hydrodésulfuration ont été utilisés à grande échelle pour le traitement des fractions pétrolieres légères lesquelles sont plus aisément desulfurées. L'application de ces procédés aux produits résiduaires lourds a été rendue difficile par les propriétés uniques de ces produits qui demandent des traitements plus sévères et plus coûteux. Deux traits principaux distinguent les produits résiduaires des distillats: les produits résiduaires contiennent1 des bases asphaltiques et d'autres structures aromatiques de haut poids moléculaire qui diminuent beaucoup la vitesse de la réaction de traitement par l'hydrogène et2 des composés tels que les composés organométalliques qui donnent des cendres durant la combustion de ces produits. Ces composés empoisonnent le catalyseur et rendent plus difficile sa régénération. Différents types de réacteurs ont été étudiés depuis quelque temps. On a ainsi développé à la fois des réacteurs à lits fixes et à lits fluidisés pour l'hydrodésulfuration des produits résiduaires. Les effets diffusionnels continuent à être un sujet de recherches. On croit généralement que ce sont là des factors importants mais quelque peu difficiles à chiffrer quantitativement. La désulfuration des produits residuaires est gén
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Abstract In 1950-1954, relatively cheap hydrogen became available from catalytic reforming and the use made of this hydrogen in refinery process is reviewed. Apart from integral feed desulphurization in catalytic reformers, by far the largest application in terms of installed plant capacity has been for the improvement of middle distillate quality, and this paper is primarily concerned with the application of hydroprocessing to refinery products distilling between 350" F and 650" F. Advances in hydrofining technology since the last World Petroleum Congress are reviewed and related to current plant designs and possible future design improvements. Résumé En 1950- 1954, le "reforming" catalytique permit d'obtenir de l'hydrogène à un prix de revient relativement modeste. Les utilisations de cet hydrogène dans les procédés de raffinage sont passées ici en revue. Mise à part la désulfuration intégrale de la charge dans les procédés de reformage catalytique, l'application de loin la plus importante, en ce qui concerne la capacité des installations de traitement en service, s'est trouvée dans l'amélioration de la qualité des distillats moyens. Le présent exposé traite tout particulièrement des applications de 1"'hydroprocessing" aux produits de raffinage distillant entre 350" F et 650" F. On retrace les progrès accomplis dans le domaine de 1"'hydrofining" depuis le dernier Congrès mondial du pétrole. On aboutit ainsi à la conception actuelle des installations et aux améliorations futures éventuelles. INTRODUCTION This paper does not attempt to present an exhaustive review of progress in distillate desulphurization but rather to pick out a few of the more interesting recent developments and analyse them against the authors' particular background. We hope in this way to promote a useful discussion. The paper is confined to distillates of lower boiling point than heavy gas oil (which is dealt with in another paper in this Panel) and primarily to middle distillates.' In the main the objective is desulphurizing, but the use of the process for the removal of instability in distillates is also briefly considered. Desulphurizing by hydrogenation under pressure is usually carried out over CoMo on alumina catalyst. Other catalysts (e.g. NiMo on alumina) are occasionally used and may show advantages in particular situations, but for a general discussion we have preferred to confine ourselves to CoMo. In the first section of the paper we attempt to assess by P. DOCKSEY and R. J. H. GILBERT, British Petroleum Company Ltd., Sunbury-on-Thames, Great Britain the scale on which it is desirable or necessary to use the process and to define the objectives for future development and design. The second section contains an examination of the bearing which the individual steps in the process have on the plant initial and operating c
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Abstract Résumé The evolution of processes for the isomerization of C4, C5 and c6 paraffins has been considered with particular emphasis on the catalyst developments which have dominated progress in this field. High activity dual-function catalysts have been developed which can operate at low temperatures under typical hydroprocessing conditions to give near equilibrium isomer yields. These new catalysts are particularly advantageous for the isomerization of pentane, hexane or mixed pentanelhexane feedstocks and selectivity is higher than with the Friedel-Crafts type of isomerization catalyst. Catalysts and processes for the isomerization of C8 aromatics are briefly discussed and the value of these processes in the preparation of p-xylene as a chemical feedstock is considered. The application of isomerization reactions in the processing of high molecular weight feedstocks plays little part in current refining operations. It is suggested that there is considerable potential for process development in the future. The hydro-isomerization of wax to produce high viscosity index lubricating oils appears to be a possible application. On a envisagé l'évolution des procédés d'isomérization des paraffines en C4, C5, et (26, en mettant tout particulièrement l'accent sur la mise au point des catalyseurs qui constitue le facteur essentiel des progrès accomplis dans le domaine considéré. On a mis au point des catalyseurs à double fonction et à activité élevée, permettant l'obtention des proportions d'isomères proches des proportions d'équilibre en opérant à basse température et dans les conditions caractéristiques du traitement d' "hydroprocessing"; Ces catalyseurs nouveaux sont particulièrement avantageux pour l'isomérization de lots de pentane, d'hexane ou de mélanges pentanelhexane et leur selectivité est supérieure à celle des catalyseurs d'isomérization du type Friedel-Crafts. On passe brièvement en revue les catalyseurs et les procédés pour l'isomérization des carbures aromatiques en C8 et on évalu leur intérêt pour la préparation du p-xylène destiné à servir de point de départ de synthèse chimique. L'application des réactions d'isomérization au traitement de fractions de masse moléculaire élevée joue un rôle limité dans les opérations de raffinage telles qu'on les pratique actuellement. On signale l'énorme potentiel de développement futur offert à de tels procédés. Une de leurs applications éventuelles semble résider dans l'isomérization de la cire de façon à obtenir des huiles lubrifiantes d'indice de viscosité élevée. INTRODUCTION Attention is concentrated mainly on light paraffin isomerization but some mention is made of xylene The purpose of this paper is not to provide a com- isomerization and the part that isomerization reactions prehensive review of isomerization reactions
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