US2885347A - Hydroforming in presence of recycled pentane and heart cut fractions - Google Patents

Hydroforming in presence of recycled pentane and heart cut fractions Download PDF

Info

Publication number
US2885347A
US2885347A US377607A US37760753A US2885347A US 2885347 A US2885347 A US 2885347A US 377607 A US377607 A US 377607A US 37760753 A US37760753 A US 37760753A US 2885347 A US2885347 A US 2885347A
Authority
US
United States
Prior art keywords
fraction
catalyst
hydroforming
reactor
line
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US377607A
Other languages
English (en)
Inventor
Charles E Hemminger
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
ExxonMobil Technology and Engineering Co
Original Assignee
Exxon Research and Engineering Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority to BE531363D priority Critical patent/BE531363A/xx
Application filed by Exxon Research and Engineering Co filed Critical Exxon Research and Engineering Co
Priority to US377607A priority patent/US2885347A/en
Application granted granted Critical
Publication of US2885347A publication Critical patent/US2885347A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
    • C10G35/00—Reforming naphtha
    • C10G35/04—Catalytic reforming
    • C10G35/10—Catalytic reforming with moving catalysts
    • C10G35/14—Catalytic reforming with moving catalysts according to the "fluidised-bed" technique

Definitions

  • the present invention relates to improvements in the hydroforming of naphthas. More particularly, the present invention relates to the hydroforming of naphthas in a process whereby not only is the octane number or value of the said stock improved but also the product is improved as to volatility characteristics.
  • Hydroforming is an operation in which virgin naphtha, cracked naphtha, or Fischer naphtha, or a mixture of two or more of these naphthas is treated at elevated temperatures and pressures in the presence of a solid catalytic material and hydrogen whereby the said naphtha is converted into a product of improved octane value.
  • the main reaction involved in hydroforming is the dehydrogenation of naphthenes.
  • other reactions occur during hydroforming such as isomerization of normal paraffins to form iso-parafiins, cyclization of parafiins such as normal heptane, followed by dehydrogenation to yield aromatics, and some hydrocracking of heavier or higher boiling paraflins to form lower boiling products.
  • the catalysts most commonly employed in hydroforming are platinum group metals supported on active alumina or group VI metal oxides such as molybdenum oxide or chromium oxide similarly supported.
  • the present invention involves treating a feed naphtha under conditions which will not only yield a product of improved octane rating in good yields but will also possess the desired volatility required in a premium gasoline.
  • the present invention involves treating the naphtha in a first stage, preferably in the presence of a fluidized bed of catalyst under hydroforming conditions, withdrawing the product from the first hydroforming stage and subjecting the product to fractional distillation to recover separately the following fractions:
  • a high boiling fraction namely, a fraction boiling above about 300 P. which also is recovered from said distillation for product.
  • Another feature of the present invention involves feeding with the naphtha, which normally boils within the range of about 200 to 350 F., a virgin or natural C fraction which may contain, for example, 75% normal pentane and 25% isopentane, the purpose here being to isomerize a substantial portion of the normal C fraction to isopentanes.
  • Another feature of the present invention involves charging the hydrogen-containing gas to the reaction zone at a point located downstream from the bottom of the bed at about the mid-point of the bed of catalyst or at a point below the mid-point of the bed of catalyst.
  • so operating is to carry out a greater portion of the dehydrogenation in the lower portion of the bed in low concentrations of recycle hydrogen-containing gas and the final portion of the dehydrogenating reaction in the upper portion of the bed in the presence of larger quantities of recycle hydrogen-containing gas.
  • the main object of the present invention is to provide a hydroforming process adapted to produce a hydroformed naphtha of good anti-detonation quality in good yields and at the same time to produce a hydroformate improved as to volatility characteristics.
  • Another object of the present invention is to provide a process adapted to hydroform naphthas to produce a product suited for blending in premium motor gasoline.
  • Another object of the present invention is to hydroform naphtha to yield hydroformed product possessing the following characteristics when blended to form a premium motor fuel, namely, (1) quick starting; (2) a volatility which, although it permits quick starting, is not over-volatilized to the extent that it may cause vapor lock; (3) the hydroformed product of the present invention has a relatively low final boiling point, namely, about 350 F.
  • Another object of the present invention is to produce a hydroformate which is a substantial portion of a premium motor fuel possessing the valuable properties of substantially complete saturation of hydrocarbons and the further valuable property of being substantially free of sulfur.
  • 1 represents a hydroforming reactor which, in a preferred modification, contains a fluidized bed of catalyst C which extends from a grid G to an upper dense phase level or interface L.
  • Gasiform material including naphtha vapors are fed to the reactor 1, as will subsequently appear, and the superficial velocity of these gases and vapors in reactor 1 are controlled so as to provide the dense fluidized bed previously referred to.
  • Above L in reactor 1 there is a light phase suspension of catalyst and gasiform material. That is to say, the concentration of catalyst in the gasiform material in reactor 1 in the space above L is much lower than the concentration of catalyst and gasiform material in the dense fluidized bed C.
  • the space in reactor 1 above L serves as a catalyst disengaging space wherein the main bulk of the catalyst is separated from the gases and vapors.
  • reactor 1 is provided with two gas distributors, namely, G and G These are foraminous members such as screens or grids.
  • G and G are foraminous members such as screens or grids.
  • a naphtha enters the system through line 2 and thus passes into a furnace 3 wherein the naphtha is vaporized and superheated to a temperature of about 950 to 1025 F. Care must be taken in preheating the naphtha to avoid thermal cracking of naphthenes contained in the feed naphtha.
  • a C hydrocarbon fraction namely, one which may contain say normal pentane and 25 isomers thereof. This hydrocarbon enters the present system through line 4.
  • the preheated naphtha and C fraction are with covered from the product purification system as will sub.-
  • the crude product in line 7 passes through a heatexchanger 8 wherein it is cooled by heat interchange with say some of the feed naphtha wherein the latter is preheated.
  • the cooled naphtha is withdrawnfrom heat exchanger 8 through line 9 and thence passed into a second cooler 10 wherein it is cooled to a temperature of about 100 F. In other words, to a temperature sufficiently low to condense the major portion of the clear liquid constituents.
  • From condenser 10 the product passes via line 11 into a separation drum 12 wherein gaseous material is separated from liquid product.
  • the latter is withdrawn from separation drum 12 through line 13 and passed to a fractional distillation column 14.
  • a side stream comprising fraction boiling within the range of from about 140 to 225 F. is passed directly to product receiving drum16.
  • a high boiling fraction namely, one boiling fro-m about 300 to 350 F., is withdrawn as bottoms from fractionator 14 and also delivered to product receiving drum 16.
  • a fraction is taken overhead through line 17 from this drum, thence passed via line 18 into a scrubber or absorber 19.
  • An absorbing oil boiling substantially in the range of about 225 to 300 F. is withdrawn from fractional distillation column 14 through line 20, thence passed via l ne 21 into a point near the top of absorption drum 19 wherein it flows downwardly against the upflowing gasiform material charged to a point near the bottom of said drum as shown whereby normal liquid constituents are dissolved out of said charged gasiform material.
  • the absorber oil and the dissolved constituents are withdrawn from absorber 19 through line 22 and charged to line 13 and thence passed to fractional distillation column 14 with the mate rial in line 13.
  • the material in line 23 may be rejected from the system or it may be treated in known manner to recover the said C -hydrocarbons.
  • a light fraction namely one boiling from C hydrocarbons to'about 225 F.
  • a heavy bottom fraction is takenofi from fractionator14 via line .15,,and also passed to product storage :16, this particular fraction being the one boiling about..-300 F.
  • the intermediate fraction that is, the fraction boiling substantially within the range of about 4 225 to 300 F., is withdrawn from fractionator 14 through line 48 and passed to product storage 16. This is the fraction which has been recycled for further treatment in reactor 1, as previously stated, to produce a premium gasoline of improved volatility for a given octane rating.
  • fractional distillation column 14 a cut or fraction is taken off overhead from said distillation column 14 through a line 26.
  • This fraction is passed to a fractional distillation column 27 which may contain as many as 60 plates wherein C and C hydrocarbons are separated from C and C hydrocarbons.
  • the C and C hydrocarbons are withdrawn overhead from 27 through line 28, and these hydrocarbons may be processed in any known manner as where, for example, the C hydrocarbons after separation from the C hydrocarbons may be converted to, say, butadiene or other chemicals by conventional processes.
  • the C hydrocarbons may'also be blended intomotor fuel to improve the Reid vapor pressure of said fuel.
  • the C hydrocarbons may be used as a fuel or treated in known manner to form chemicals by known means.
  • the bottoms fraction from fractionator 27 is withdrawn through line 29 and fed to the middle of fractional distillation column 30 wherein isopentanes are separated from the normal pentane and recovered overhead through line 31 and delivered to product storage 16.
  • the higher boiling normal pentane is withdrawn from fractional distillation column 30 through line 32 and delivered to line 25 and thereafter recycled with the said heart cut material in that line via lines 2 and 6 to reactor 1 wherein these normal paraffins, which may be mixed with some C hydrocarbons, undergo isomerization to form theiso derivatives possessing higher anti-detonation qualities than the normal parafiins.
  • the overhead gasiform material in line 17 is in part recirculated via line 33 and reheat furnace 34 and line 35 to line 37 from which it is passed into line 6 for return to the bottom portion of reactor 1.
  • a portion of the gas in line 35 may be passed via line 38 into reactor 1 at a point above grid G
  • a portion of the recycle gas in line 33 which is a cold gas, is passed via branch line 36 into line 38 and flows with the hot gas in this line into reactor 1 as shown in the drawing. It will be noted that only a portion of this recycle hydrogencontaining gas is charged to the bottom of reactor 1.
  • the purpose of so operating is to provide an atmosphere in reactor 1 which contains lesshydrogen in the lower portion of reactor 1 than is contained in the portion above G
  • the catalyst in reactor 1 acquires carbonaceous deposits and perhaps also deposits containing sulfur. It is necessary to regenerate the catalyst to remove such deposits and to restore the catalyst activity.
  • catalyst is withdrawn from reactor I through a stripping zone 40, the catalyst entering said stripping zone through an opening or orifice 39. Steam is charged to the bottom of said stripping zone 40 through a pipe 41, which steam passes upwardly against the downflowing catalyst, and dislodges volatile hydrocarbons therefrom, which hydrocarbons are carried upwardly with the steam into the reactor at a point above the dense phase level L, thus avoiding contacting steam with the main body of catalyst C.
  • the catalyst from stripper 40 is charged into a stream of air flowing in pipe 42 wherein it is formed into a suspension and carried into regenerator 43.
  • the bottom of standpipe or stripper 40 is provided with a valve V to control the flow of catalyst into the air stream in 42.
  • the quantity of air in line 42 is about 10% of the total air required in regenerator 43 to consume the deposits on the catalyst.
  • Supplemental air is added to regenerator 43 through line 44.
  • Regencrator 43 may be of the same construction as reactor 1 but very much smaller. As usual, it is provided with gas distributing means G through which the suspension and the air pass into the regenerator to form a fluidized mass extending from G to an upper dense phase level L formed by controlling the superficial linear velocity of the gasiform material in regenerator 43.
  • regenerator 43 The space above L in regenerator 43 is a catalyst disengaging space wherein the main bulk of the catalyst is separated from the gas.
  • regenerator 43 In the top of regenerator 43 there is disposed one or more cyclones S or dust separators which separate entrained catalyst which is returned to the main fluidized bed C through one or more dip pipes al.
  • the fumes pass from the regenerator through exit pipe 45, and since they contain appreciable quantities of sensible heat and also some potential chemical heat, the heat content thereof may be utilized in the present system, according to conventional means.
  • the conditions under which the regeneration is carried out will be described in detail hereinafter.
  • the regenerated catalyst is withdrawn from regenerator 43 through line 46 and returned to reactor 1 at a point in close proximity to but above the grid G at a point spaced from stripper pipe 40.
  • the freshly regenerated hot catalyst is not charged to the lower portion of the hydroformer 1 for the reason that hot vapors and gas enter at the bottom of the reactor supplying heat.
  • catalyst above G passes downwardly through a downcomer 47 into a bed of catalyst between G and G and catalyst passes upwardly from this region through grid G into the upper portion of the catalyst bed C.
  • a fed was hydroformed using a catalyst consisting of about 10% molybdenum oxide and 90% aluminum oxide, the foregoing percentages being by weight.
  • a naphtha containing 10% aromatics, 45% naphthene and 45 paraffins with 55 research octane number and the natural C fraction containing 75% normal pentane and 25% isopentane were mixed and fed to the hydroforming zone.
  • barrel of the said components derived from natural gas was fed to the reaction zone.
  • the hydroforming operation was carried out at a temperature of 935 F. in the lower portion of the bed and 905 F. in the upper portion of the bed.
  • the oil was fed to the reaction zone at a rate of 0.6 lb. of oil per hour per lb.
  • a heart out boiling substantially within the range of 225 to 300 F. from the previously hydroformed naphtha was also fed to the reaction zone as recycled material.
  • the amount of the said heart cut with respect to the fresh oil feed was 0.3 barrel per barrel of fresh feed.
  • the amount of normal C hydrocarbons recycled to the hydroforming zone, with respect to the fresh naphtha feed, was 0.6 barrel per barrel of fresh 1 Exclusive 01 extraneous 0 added to system.
  • the present invention involves a hydroforming process preferably using a fluidized bed of hydroforming catalyst characterized in that a middle fraction of the reformed naphtha is recycled to the reforming zone.
  • This recycling effects a distinct improvement in the volatility, at a given octane rating, of the reformed naphtha which is an important factor in the manufacturing of preminum quality gasoline.
  • the present invention is not limited to the use of a molybdenum oxide catalyst but rather a platinum group metal catalyst may be used.
  • a platinum group metal catalyst may be used.
  • an alumina-platinum group metal catalyst containing 0.05 to 5 weight percent platinum or 1.5 weight percent palladium may be used.
  • the operating conditions in the case of these catalysts would be: temperature of catalyst bed-800900 F., pressure in hydroformer 100700 p.s.i.g.; hydrogen charged to reactor per barrel of oil feedl0005000 standard cubic feet; residence time of oil in reactor as represented by oil feed rate-1 to 10 lbs. of oil per hour per lb. of catalyst in reactor.
  • the method of hydroforming hydrocarbon fractions boiling in the naphtha boiling range which comprises contacting the naphtha vapors at elevated temperatures and pressures with a bed of a hydroforming catalyst in the presence of hydrogen in a hydroforming zone for a suflicient period of time to effect the desired conversion, withdrawing crude product from the hydroforming zone, subjecting the hydroformate to fractional distillation to separate the 125225 F. fraction, the C fraction, a 225 300 F. heart cut fraction and a 300 F.+ fraction, passing the entire 125-225 F. fraction and the entire 300 F.+ fraction to product, passing a portion of the 225 to 300 F.
  • a continuous method for hydroformig hydrocarbon fractions boiling in the naphtha boiling range which comprises charging the naphtha vapors to a hydroforming zone containing a fluidized bed of a hydroforming catalyst which bed of catalyst is disposed, in part, in the lower portion of a hydroforming zone and, in part, in another portion disposed immediately above the firstnamed portion, the two portions being separated and in communication with each other, charging preheated naphtha and a hydrogen-containing gas to the hydroforming zone, permitting contact between the said naphtha vapors and the portions of said bed of catalyst at hydroforming conditions of temperature and pressure for a sufficient period of time to effect the desired conversion, withdrawing a product from said hydroforming zone, subjecting the hydroformate to fractional distillation to separate the -225 F.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Production Of Liquid Hydrocarbon Mixture For Refining Petroleum (AREA)
US377607A 1953-08-31 1953-08-31 Hydroforming in presence of recycled pentane and heart cut fractions Expired - Lifetime US2885347A (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
BE531363D BE531363A (zh) 1953-08-31
US377607A US2885347A (en) 1953-08-31 1953-08-31 Hydroforming in presence of recycled pentane and heart cut fractions

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US377607A US2885347A (en) 1953-08-31 1953-08-31 Hydroforming in presence of recycled pentane and heart cut fractions

Publications (1)

Publication Number Publication Date
US2885347A true US2885347A (en) 1959-05-05

Family

ID=23489793

Family Applications (1)

Application Number Title Priority Date Filing Date
US377607A Expired - Lifetime US2885347A (en) 1953-08-31 1953-08-31 Hydroforming in presence of recycled pentane and heart cut fractions

Country Status (2)

Country Link
US (1) US2885347A (zh)
BE (1) BE531363A (zh)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20100018899A1 (en) * 2008-07-24 2010-01-28 Krupa Steven L Process and apparatus for producing a reformate by introducing isopentane
US20120012504A1 (en) * 2009-03-27 2012-01-19 Hideki Minami Method for producing aromatic hydrocarbons

Citations (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2349045A (en) * 1939-09-18 1944-05-16 Standard Oil Co Dehydro-aromatization
US2374095A (en) * 1942-07-27 1945-04-17 Phillips Petroleum Co Process for the catalytic treatment of hydrocarbons
US2380938A (en) * 1941-01-14 1945-08-07 Standard Oil Co Process of inhibiting cracking in re-forming of hydrocarbons
US2389342A (en) * 1942-08-10 1945-11-20 Phillips Petroleum Co Catalytic dehydrogenation
US2472844A (en) * 1942-06-25 1949-06-14 Standard Oil Dev Co Maintenance of catalyst activity in hydrocarbon conversion processes
US2484381A (en) * 1947-07-26 1949-10-11 California Research Corp Purification of carbonyl sulfide contaminated hydrocarbon gases
US2596145A (en) * 1948-12-21 1952-05-13 Universal Oil Prod Co Method of catalytically reforming hydrocarbons
US2697684A (en) * 1951-11-28 1954-12-21 Standard Oil Dev Co Reforming of naphthas
US2718535A (en) * 1952-03-18 1955-09-20 Gulf Research Development Co Hydroisomerization of hydrocarbons
US2736684A (en) * 1952-09-05 1956-02-28 Kellogg M W Co Reforming process
US2740751A (en) * 1952-02-23 1956-04-03 Universal Oil Prod Co Reforming of both straight run and cracked gasolines to provide high octane fuels
US2776247A (en) * 1951-09-24 1957-01-01 Gulf Research Development Co Fluid catalytic hydroreforming with carbonized catalyst
US2781298A (en) * 1952-03-14 1957-02-12 Universal Oil Prod Co Combined operation for catalytically upgrading gasoline

Patent Citations (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2349045A (en) * 1939-09-18 1944-05-16 Standard Oil Co Dehydro-aromatization
US2380938A (en) * 1941-01-14 1945-08-07 Standard Oil Co Process of inhibiting cracking in re-forming of hydrocarbons
US2472844A (en) * 1942-06-25 1949-06-14 Standard Oil Dev Co Maintenance of catalyst activity in hydrocarbon conversion processes
US2374095A (en) * 1942-07-27 1945-04-17 Phillips Petroleum Co Process for the catalytic treatment of hydrocarbons
US2389342A (en) * 1942-08-10 1945-11-20 Phillips Petroleum Co Catalytic dehydrogenation
US2484381A (en) * 1947-07-26 1949-10-11 California Research Corp Purification of carbonyl sulfide contaminated hydrocarbon gases
US2596145A (en) * 1948-12-21 1952-05-13 Universal Oil Prod Co Method of catalytically reforming hydrocarbons
US2776247A (en) * 1951-09-24 1957-01-01 Gulf Research Development Co Fluid catalytic hydroreforming with carbonized catalyst
US2697684A (en) * 1951-11-28 1954-12-21 Standard Oil Dev Co Reforming of naphthas
US2740751A (en) * 1952-02-23 1956-04-03 Universal Oil Prod Co Reforming of both straight run and cracked gasolines to provide high octane fuels
US2781298A (en) * 1952-03-14 1957-02-12 Universal Oil Prod Co Combined operation for catalytically upgrading gasoline
US2718535A (en) * 1952-03-18 1955-09-20 Gulf Research Development Co Hydroisomerization of hydrocarbons
US2736684A (en) * 1952-09-05 1956-02-28 Kellogg M W Co Reforming process

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20100018899A1 (en) * 2008-07-24 2010-01-28 Krupa Steven L Process and apparatus for producing a reformate by introducing isopentane
US8753503B2 (en) * 2008-07-24 2014-06-17 Uop Llc Process and apparatus for producing a reformate by introducing isopentane
US20120012504A1 (en) * 2009-03-27 2012-01-19 Hideki Minami Method for producing aromatic hydrocarbons

Also Published As

Publication number Publication date
BE531363A (zh)

Similar Documents

Publication Publication Date Title
US2472844A (en) Maintenance of catalyst activity in hydrocarbon conversion processes
US2697684A (en) Reforming of naphthas
US2758062A (en) Two-stage hydroforming process
US3364134A (en) Black oil conversion and desulfurization process
US2780661A (en) Reforming followed by hydrodealkylation
US2736684A (en) Reforming process
US3230164A (en) Hydrocracking process to produce gasoline and turbine fuels
US3442792A (en) Process for improving motor octane of olefinic naphthas
US3026260A (en) Three-stage hydrocarbon hydrocracking process
US2320147A (en) Aromatization
US2270715A (en) Catalytic treatment of petroleum distillates
US2757128A (en) Low pressure hydrogenation and hydrogen regeneration of the catalyst
US3580837A (en) Hydrorefining of coke-forming hydrocarbon distillates
US2765264A (en) Reforming without recycle hydrogen
US3691059A (en) Hydrogen-cascade process for hydrocarbon conversion
US2758063A (en) Method of regenerating hydroforming catalysts
US3042196A (en) Catalytic conversion of hydrocarbon oils with the use of different types of feed oils
US2426870A (en) Process for simultaneously dehydrogenating naphthenes and hydrogenating olefins
US2934492A (en) Hydrogenation of heavy oils
US2710826A (en) Method for hydroforming naphthas
US2769769A (en) Two stage high octane gasoline product
US2885347A (en) Hydroforming in presence of recycled pentane and heart cut fractions
US3116232A (en) Process for upgrading cracked gasoline fractions
US2899380A (en) Charge oil
US3071536A (en) Hydrocarbon conversion process