Sélection de la langue

Search

Sommaire du brevet 1300544 

Énoncé de désistement de responsabilité concernant l'information provenant de tiers

Une partie des informations de ce site Web a été fournie par des sources externes. Le gouvernement du Canada n'assume aucune responsabilité concernant la précision, l'actualité ou la fiabilité des informations fournies par les sources externes. Les utilisateurs qui désirent employer cette information devraient consulter directement la source des informations. Le contenu fourni par les sources externes n'est pas assujetti aux exigences sur les langues officielles, la protection des renseignements personnels et l'accessibilité.

Disponibilité de l'Abrégé et des Revendications

L'apparition de différences dans le texte et l'image des Revendications et de l'Abrégé dépend du moment auquel le document est publié. Les textes des Revendications et de l'Abrégé sont affichés :

  • lorsque la demande peut être examinée par le public;
  • lorsque le brevet est émis (délivrance).
(12) Brevet: (11) CA 1300544
(21) Numéro de la demande: 1300544
(54) Titre français: METHODE DE CATALYSE NON OXYDATIVE POUR L'ADOUCISSEMENT D'UNE FRACTION D'HYDROCARBURE ACIDE
(54) Titre anglais: NON-OXIDATIVE CATALYTIC METHOD OF SWEETENING A SOUR HYDROCARBON FRACTION
Statut: Durée expirée - après l'octroi
Données bibliographiques
(51) Classification internationale des brevets (CIB):
  • C10G 29/20 (2006.01)
  • C10G 29/06 (2006.01)
  • C10G 29/16 (2006.01)
  • C10G 29/28 (2006.01)
(72) Inventeurs :
  • IMAI, TAMOTSU (Etats-Unis d'Amérique)
  • BRICKER, JEFFERY C. (Etats-Unis d'Amérique)
(73) Titulaires :
  • UOP
(71) Demandeurs :
  • UOP (Etats-Unis d'Amérique)
(74) Agent: MACRAE & CO.
(74) Co-agent:
(45) Délivré: 1992-05-12
(22) Date de dépôt: 1988-09-23
Licence disponible: S.O.
Cédé au domaine public: S.O.
(25) Langue des documents déposés: Anglais

Traité de coopération en matière de brevets (PCT): Non

(30) Données de priorité de la demande: S.O.

Abrégés

Abrégé anglais


"A NON-OXIDATIVE CATALYTIC METHOD
OF SWEETENING A SOUR HYDROCARBON FRACTION
ABSTRACT
A sour hydrocarbon fraction is sweetened by
treating the sour hydrocarbon fraction containing mercaptans
with sufficient unsaturated hydrocarbons in the presence of
an acid-type catalyst at non-oxidative reaction conditions
selected to convert said mercaptans to thioethers. Acid
type catalysts which may be used include polymeric sulfonic
acid resins, intercalate compounds, solid acid catalysts and
acidic inorganic oxide catalysts.

Revendications

Note : Les revendications sont présentées dans la langue officielle dans laquelle elles ont été soumises.


17
CLAIMS:
1. A non-oxidative process for sweetening a
sour hydrocarbon fraction containing mercaptans which
comprises reacting the mercaptans contained in said sour
hydrocarbon fraction and an unsaturated hydrocarbon with
an acid catalyst selected from the group consisting of an
acidic inorganic oxide, a polymeric sulfonic acid resin,
an intercalate compound, a boron halide dispersed on
alumina, and an aluminum halide dispersed on alumina,
under a non-oxidizing atmosphere at reaction conditions
selected to convert said mercaptans to thioethers and
recovering said sweetened hydrocarbon fraction.
2. The process of Claim 1 where said
unsaturated hydrocarbon is present as a component of said
sour hydrocarbon fraction in an amount at least equal to
the molar amount of mercaptans present in said fraction.
3. The process of Claim 1 where said
unsaturated hydrocarbon is added to said sour hydrocarbon
fraction in a concentration of at least the molar amount
of the mercaptans in said sour hydrocarbon fraction to
about 20 weight percent of the sour hydrocarbon fraction
prior to contacting said sour hydrocarbon with said acid-
type catalyst.
4. The process of Claim 1 where said
unsaturated hydrocarbon contains a tertiary carbon atom.
5. The process of Claim 1 further characterized
in that said reaction conditions comprise a temperature in
the range of from about 25° to about 350°C, a pressure in
the range of from about 0.01 to about 25 atmospheres and a
LHSV in the range of from about 1 to about 10.
6. The process of Claim 1 where said acidic
inorganic oxide is selected from the group consisting of
alumina, silica-alumina, mordenite, L-zeolite, omega-
zeolite, X-zeolite, Y-zeolite and phosphoric acid
dispersed on alumina.

18
7. The process of Claim 1 where said
intercalate compound is antimony pentafluoride on graphite
or zirconium halide on graphite.

Description

Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.


~3(~S~
"A NON-OXIDATIVE CATYALYTIC METHOD
OF SWEETENING ~ SOUR HYDROCARBON FRACTION"
FIELD OF THE INVENTION
The present invention relates to a unique non-
oxidative method of sweetening sour hydrocarbon streams
using an unsaturated hydrocarbon and an acid catalyst
together with appropriate thioether producing conditions.
BACKGR~UND OF THE INV:ENTION
Processes for the treatment of a sour
hydrocarbon fraction wherein the fraction is treated by
contacting said fraction with an oxidation catalyst in the
presence of an oxidizing agent and an alkaline component
have become well-known and widely practiced in the
petroleum refining industry. Said processes are typically
designed to effect the oxidation of offensive mercaptans
contained in a sour hydrocarbon fraction with the
formation of innocuous disulfides--a process commonly
referred to as sweetening. The oxidizing agent is most
often air. Gasoline, including natural, straight run and
cracked gasolines, is the most frequently treated sour
hydrocarbon fraction. Other sour hydrocarbon fractions
include the normally gaseous petroleum fractions as well
as naphtha, kerosene, iet fuel, fuel oil, lube oil, and
the like.
A commonly used continuous process for treating
a sour hydrocarbon fraction entails treating the
distillate in contact with a metal phthalocyanine catalyst
dispersed in an aqyeous caustic solution to yield a doctor
sweet product. The sour hydrocarbon fraction and the
catalyst containing aqueous caustic solution provide a
liquid-liquid system wherein mercaptans are converted to
disulfides at the interface of the immiscible solutions in
the presence of an oxidizing agent--usually air. Sour

~3~S~
hydrocarbon fractions containing more difficult to oxidize
mercaptans are more effectively treated by contacting with
a metal chelate catalyst disposed vn a high surface area
adsorptive support--usually a metal phthalocyanine on an
activated charcoal. The sour fraction is treated by
contacting with the supported metal chelate catalyst at
oxidation conditions in the presence of an alkaline agent.
One such process is described in U.S. Patent No.
2,988,500. The oxidizing agent is most often air admixed
with the hydrocarbon fraction to be treated, and the
alkaline agent is most often an aqueous caustic solution
charged continuously to the process or intermittently as
required to maintain the catalyst in the caustic-wetted
state.
Heretofore, the practice of catalytical}y
treating mercaptan containing sour hydrocarbon fractions
has involved the introduction of alkaline agents~ usually
sodium hydroxide, into the sour petroleum distillate prior
to or during the treating operation. (U.S. Patent Nos.
3,108,081 and 4,156,641). These patents along with
several others which teach improvements of the basic
process all deal with an oxidative method of treating
mercaptans in a sour hydrocarbon fraction.
U.S. Patent 3,894,107 teaches the conversion of
heteroatom compounds to higher hydrocarbons over a
particular type of aluminosilicate molecular sieve at
temperatures of 300C - 500C, in the gas phase. Thus, if
mercaptans are used in this process, the resultant
products would be higher hydrocarbons and H2S. The
formation of H2S would present a disposal problem.
Therefore, because of the H2S disposal problem and the
high temperatures involved, this process is not useful as
a hydrocarbon sweetening process.
The present invention discloses a non-oxidative
method of sweetening a sour hydrocarbon fraction
comprising contacting a mercaptan containing sour

~3C~:IS~
hydrocarbon fractions with an acid type catalyst in the
presence of an unsaturated hydrocarbon, thereby converting
said mercaptans to thioethers. Th~ ins~an~ invention has
the advantage over the oxidative method of the prior art
in that no alkaline agent is involved in the present
invention and therefore the problem of disposing of the
spent alkaline agent is eliminated.
SUMMARY OF THE INVENTION
It is a broad objective of this invention to
present a novel non-oxidative process for treating a sour
hydrocarbon fraction. Specifically, one embodiment of the
invention is a process for sweetening a sour hydrocarbon
fraction containing mercaptans which comprises contacting
said sour hydrocarbon fraction containing at least a
concentration of an unsaturated hydrocarbon e~lal to the
molar amount of mercaptans present in said sour
hydrocarbon fraction with an acid-type catalyst at non-
oxidative reaction conditions selected to convert said
mercaptans to thioethers and recovering said sweetened
hydrocarbon fraction.
In a specific embodiment of this invention a
sour hydrocarbon fraction which contains mercaptans and
unsaturated hydrocarbons in appropriate amounts is
continuously contacted with an acidic resin at conditions
selected to convert the mercaptans to thioethers and
recovering the sweetened hydrocarbon fraction.
Other objects and embodiments of this invention
will become apparent in the following detailed
description.

~3~35~L
BRIEF DESCRIPTION OE THE DRAWINGS
Figure 1 i5 a graphical representation of the
performance of one of the catalysts of the present
invention, catalyst A. The amount of residual mercaptan
in the hydrocarbon fraction is plotted versus time on
stream.
Fiyure 2 is a graphical comparison of the
durability of catalyst A when it is used o treat an acid
washed sour hydrocarbon stream versus when it is used to
treat an unwashed sour hydrocarbon stream. The conversion
of mercaptans to thioethers is plotted versus time on
stream.
DETAILED DESCRIPTION OF THE INVENTION
The reaction of thiols with olefins possessing
electron withdrawing functions is known (A.N. Glazer,
Annual Rev. Biochem., 39, 108 (1970); W. L. Baker, J.
Chem. Tech. Biotechnol., 34A, 227-236 (1984).
RSH + fH = CH ~ RS--CH--fH2
O = C C = O O = C f = O
ET ET
However, this is a stoichiometric reaction which
is not useful as a catalytic sweetening agent due to a low
reaction rate. This invention describes a catalytic
method for converting mercaptans through reaction with
unsaturated hydrocarbons in the presence of an acid

~3~154~
catalyst and thereby provides a non-oxidati~e method of
sweetening a sour hydrocarbon fraction. The generalized
reaction can be written as follows:
R R R R
~+
R'SH + C = C ~ C - C
R R R H S R
R'
where each R is individually selected from the group
consisting of hydrogen, an alkyl hydrocarbon, a cycloalkyl
hydrocarbon, an aryl hydrocarbon, an alkaryl hydrocarbon
and an aralkyl hydrocarbon. If R is any of the
hydrocarbonc listed above, the hydrocarbon may contain up
to about 25 carbon atoms. It is preferable to choose each
R such that the unsaturated hydrocarbon contains a
tertiary carbon atom. R'SH represents any mercaptan
compound where R' is a hydrocarbon radical containing up
to about 25 carbon atoms and is selected from the group
consisting of alkyl, cycloalkyl, aryl, alkaryl, and
aralkyl.
The above equation shows that an acid type
catalyst can catalyze the reaction of mercaptans with an
unsaturated hydrocarbon to give thioethers which are
acceptable products. Typical catalysts which were found
to be effective in promoting the thioetherification
reaction include but are not limited to acidic reticular
polymeric resins, intercalate compounds, solid acid
catalysts, acidic inorganic oxides and metal sulfates.
More specifically, examples of acidic polymeric resins are
resins which contain a sulfonic acid group. Although both
macro- and microreticular polymeric sulfonic acid resins
may be used, it is preferred to use macroreticular
polymeric sulfonic acid resins. These types of resins are
well known in the art and are available commercially.

~30~JSL9~
An intercalate compound is defined as a material
which has a layer of cations between the planes of a
crystal lattice. Only intercalate compounds which are
acidic are contemplated as within the scope of this
invention. Examples of acidic intercalate compounds are
antimony halides in graphite, aluminum halides in
graphite, and zirconium halides in graphite. A preferred
intercalate compound is antimony pentafluoride in
graphite. Again these compounds are commercially
available.
Solid acid catalysts have also been found to
catalyze the conversion of mercaptans to thioethers.
Examples of one type of solid acid catalysts are
phosphoric acid, sulfuric acid or boric acid supported on
an inorganic oxide support such as silica, alumina,
silica-aluminas, kieselguhr or clays. These acid
catalysts are usually prepared by reacting the desired
liquid acid with the desired support and drying. Examples
of another type of solid acid catalysts are acidic
inorganic oxides. Acidic inorganic oxide catalysts which
may be used in this invention may be selected from the
group consisting of aluminas, silica-aluminas, natural and
synthetic pillared clays, and natural and synthetic
zeolites such as faujasites, mordenites, L, omega, X and Y
zeolites. Many of these oxides can either be synthesized
or preferably can be obtained from commercial sources.
A subgroup of acidic inorganic oxides which are
within the scope of the invention are aluminas or silica-
aluminas which have been impregnated with aluminum halides
or boron halides. A preferred catalyst of this type is
boron trifluoride deposited on alumina. Finally, metal
sulfates such as zirconium sulfate, nickel sulfate,
chromium sulfate, cobalt sulfate, etc. can also be used in
this invention.
Regardless of what type of catalyst is employed
in the present invention, it is preferred that the

~3(~
catalyst be in particulate form, which particles have an
average diam~ter of less than 4.0 mm. Additionally, it is
preferred that the average particle size (average
diameter) be in the ran~e of about 105 microns to about
4.0 mm. If the catalyst particle size is smaller than 105
microns, excessive backpressure is created in the treating
zone.
Examples of sour hydrocarbon fractions which can
be treated using the process of the present invention
includes FCC gasoline, kerosene, thermally cracked
gasoline, straight run naphtha, LPG and fuel oil. It is
pref~rred that the sour hydrocarbon fraction contain an
unsaturated hydrocarbon. In principle, any unsaturated
hydrocarbon may be used and may be selected from the group
consisting of olefins, diolefins, alkynes, etc. However,
it is preferable to utilize an unsaturated hydrocarbon
which is capable of forming a tertiary carbonium ion in
the presence of an acid catalyst. Examples of
hydrocarbons which have an unsaturated carbon-carbon bond
with one of said unsaturated carbons also being a tertiary
carbon atom are isobutylene, 3-methyl-1-butene,
2-methyl-2-butene, 2-methyl-1-butene, 2-methyl-1-pentene,
etc. bond and a tertiary carbon atom are particularly
preferred.
The concentration of the unsaturated hydrocarbon
necessary to carry out the process of the instant
invention can vary considerably. However, a concentration
of unsaturated hydrocarbon of at least equal to the molar
amount of the mercaptans present in said sour hydrocarbon
fraction is necessary to effectively carry out the
process. In the event that the sour hydrocarbon fraction
- does not contain an unsaturated hydrocarbon, one can be
added to the sour hydrocarbon fraction prior to contact
with the fixed bed catalyst. When the unsaturated
hydrocarbon is added to the sour hydrocarbon fraction, it
i5 desirable that it b~ added in a concentration of at

~3~5~
least the molar concentration of the mercaptans in said
sour hydrocarbon fraction to about 20 weight percent of
the sour hydrocarbon fraction. The upper limit is imposed
more by economic considerations rather than any practical
S limitations of the process. A recommended concentration
range of unsaturated hydrocarbon is about 0.01 weight
percent to about 20 weight percent.
The process of the instant invention is carried
out by passing the sour hydrocarbon fraction over a fixed
bed acid-catalyst which is installed in a reaction zone.
The fixed bed catalyst can be placed in either a vertical
or a horizontal reaction zone. If a vertical reaction
zone is chosen, the sour hydrocarbon fraction can be
passed upwardly or downwardly through the fixed bed. The
methods of supporting beds of solid material in reaction
20nes are well known and need not be described in detail
herein.
The sour hydrocarbon fraction is introduced into
the reaction æone by a feed line and the flow is
controlled by means well known in the art. The flow of
the hydrocarbon fraction is controlled to give a contact
time in the reaction zone so that the desired conversion
of mercaptans to thioethers is achieved. Specifically,
contact times equivalent to a liquid hourly space velocity
(LHSV) of about 0.5 to about 10 are effective to achieve a
desired conversion of mercaptans to thioethers.
Additional~y, treatment of the sour hydrocarbon
fraction in the reaction zone is generally effected in a
temperature range of about 25 to about 350C with a
preferred temperature range of about 25C to about 200C.
The reaction is carried out at a pressure of abolt 0.01 to
about 25 atmospheres with a pressure in the range of about
1 to about 10 atmospheres being preferred.
; Since thioetherification is a non-oxidative
reaction, it is preferred that the contact of hydrocarbon
fraction with the acid catalyst take place under a non-
8-

~3~5~
oxidative atmosphere. The prevention of contact between
oxygen and hydrocarbon under the refinery conditions is
easily accomplished using standard operating procedures.
If it is necessary to add an unsaturated
hydrocarbon to the reaction zone to effect the
thioetherification reaction, the unsaturated hydrocarbon
can be added to the sour hydrocarbon fraction at the start
of the reaction zone but well before the fixed bed acid
catalyst. This will ensure that the unsaturated
hydrocarbon is well dispersed in ~he sour hydrocarbon
fraction. It is contemplated that any unreacted
unsaturated hydrocarbon could be separated at the reactor
outlet and recycled to the inlet of the catalyst bed.
For example, the sweetening of high molecular
weight petroleum fractions (kerosene, fuel oil) might be
accomplished by addition of excese isobutylene to the
hydrocarbon feed over an acid catalyst. The separation
and recycle of unreacted isobutylene could be employed to
increase sweetening rate and minimize the use of
isobutylene.
Alternatively, the entire process can be carried
out in a batch process. The pressure conditions,
temperature conditions and unsaturated hydrocarbon
concentration employed for the flow type process can be
used for a batch process. However, the contact time in
the reaction zone will depend on the amount of catalyst,
the size of the reaction zone, and the amount cf sour
hydrocarbon in the reaction zone. Based on these
considerations, an appropriate conversion of mercaptan to
thioether is accomplished with a contact time in the range
of from about 0.05 to about 2 hours.
In some instances the acid catalyst can be
deactivated by basic nitrogen compounds present in the
sour hydrocarbon fraction. Thus, in order to minimize
catalyst deactivation, it is desirable to treat the sour
hydrocarbon fraction to remove the basic nitrogen

~3~5'~
compounds prior to contacting the sour hydrocarbon
fraction with the acid catalyst.
Removal of the basic nitrogen compounds can be
accomplished by several methods known in the art,
including an acid wash or the use of a guard bed
positioned prior to the aci~ catalyst. Examples of
~fective guard beds include A-zeolite, Y-zeolite,
L-zeolite, mordenite and acidic r~ticular polymeric
resins. If a guard bed technique is employed, it is
contemplated that dual guard beds ba placed prior to the
reactor such that regeneration of one guard bed ~ay be
conducted while the alternate guard bed is functioning.
In this manner continuous operation of the unit may be
achieved. When an acid wash is desired, the sour
hydrocarbon fraction can be treated with an aqueous
solution of the acid. The concentration of said acid in
said aqueous solution is not critical, but is conveniently
chosen to be in the range of about 0.5 to about 30 weight
percent. The acid which can be used to treat the sour
hydrocarbon fraction may be chosen from the group
consisting of hydrochloric, sulfuric, acetic, etc., with
hydrochloric acid being preferred.
One method of effecting the acid wash involves
introducing a sour hydrocarbon stream into the lower
portion of an extraction column. The sour hydrocarbon
stream rises upward through contactin~ plates or trays
toward the top of the extractor counter-current to a
descending stream of an aqueous acid solution. Upon
contact of the aqueous acid solution with the sour
hydrocarbon fraction, the basic nitrogen compounds
contained in said sour hydrocarbon fraction are extracted
into the aqueous acid solution. The sour hydrocarbon
fraction continues upward past the point in the upper
portion of the column at which the a~ueous acid solution
is introduced and then is removed. The resultant basic

:3L30(~5~9~
11
nitrogen compound containing aqueous acid solution is
removed from the bottom of the reactor and disposed.
This acid wash treatment is usually done at
ambient tempera$ure and atmospheric pressure, although
temperatures in the range of about 20 to about 70C and
pressure in the range of about 1.0 to about 17.2
atmospheres can be used. The rate of flow of the acid
solution will be about 0.1 times to about 3.0 times of the
rate of flow of the sour hydrocarbon feed. Carrying out
the acid wash under the above conditions will generally
result in the removal of about 60-95~ weight percent of
the basic nitrogen compounds.
In order to more fully illustrate the advantages
to be derived from the instant invention, the following
examples are provided. It is to be understood that the
examples are by way of illustration only and are not
intended as an undue limitation on the broad scope of the
invention as set forth in the appended claims.
EXAMPLE T
A macroreticular polymeric sulfonic acid resin
was obtained from ~he Rohm and Haas Co. This resin is
sold under the TM Amberlite XE-372 and comes in the
shape of spheres about 16-50 U.S. mesh size (1.19 mm to
297 micron diameter). The resin was used as received and
was designated catalyst A.
EXAMPLE II
A macroreticular polymeric sulfonic acid resin
was obtained from the Rohm and Haas Co. ~his resin is
sold under the TM Amberlyst 15 and comes in the shape of
spheres about 16-50 U.S. mesh size (1.19 mm to 297 micron
diameter). The resin was used as received and was
designated catalyst B.

~3~J~S44
12
EXAMPLE III
A macroreticular polymeric sulfonic acid resin
was obtained from the Rohm and ~aas Co. This resin is
sold under the TM Amb~rlite 252 and comes in the shape
of spheres about 16-50 U.S. mesh size (3.19 mm to 297
micron diameter). The resin was used aE; received and was
designated catalyst C.
EXAMPLE IV
An intercalate compound consisting of antimony
pentafluoride on graphite was obtained from Alfa Chemical
Co. This catalyst was used as received and was designated
catalyst D.
EXAMPLE V
A solid phosphoric acid catalyst was prepared by
adding kieselguhr powder to an 85% polyphosphoric acid
solution and mixing for 3-7 minutes. After formation of a
consistent mixture the material was extruded, sized and
dried at 380~C. This catalyst was designated catalyst E.
EXAMPLE VI
Catalyst F was prepared by passing BF3 gas at an
hourly space velocity of 700 hr 1 over an anhydrous gamma
alumina support for two hours. The catalyst was loaded
into the reactor under a nitrogen atmosphere.
The catalysts of Example I to VI were studied in
a test designed to evaluate the activity and durability of
these catalysts.
;; A

~3~
The test involved loading a sample of the
catalyst (50 cc) to be evaluated into a 0.5" by 6.5"
(12.7 by 165.1 mm) catalyst reaction zone where it was
supported by screens. In the standard test method, the
reactor zone containing catalyst was purged with nitrogen
for a sufficient time to remove all gaseous oxygen from
the system. A sour hydrocarbon feedstock having ~;the
properties specified in Table 1 and containing
approximately 200 weight ppm of ~ercaptans sulfur was fed
under a nitrogen blanket to the catalyst zone in the
liquid phase at a rate of 100 cc/hr, equivalent to a
LHSV = 2.0 hr 1. The reactor zone inlet temperature was
controlled at 30C and the reactor pressure was one
atmosphere. Samples were taken for mercaptan analysis at
regular intervals of 1 hour utilizing a nitrogen-purged
sampling box. The temperature in the catalyst zone was
measured hourly to determine the extent of the exothermic
reaction versus time on stream. No addition of olefin was
made to the feedstock.
Table 1
SOUR FCC GASOLINE PROPERTIES
Mercaptan Sulfur, wppm 193
Total Sulfur, wt % 0.32
A.P.I. Gravity, 60F (15.6C) 56.8
Aromatic content, % 29.0
Olefin content, % 24.9
Paraffin content, % 46.1
End Pt., C 220C

~3~5~4
1~
Results of the activity test as described in
Example VII are presented in Table 2.
Table_2
Catalyst I.D. Mercaptan
Conversion,Percent
Catalyst A 88
Catalyst B 88
Catalyst C 18
Catalyst D 95
Catalyst E 93
Catalyst F 85
The results presented in the Table show that a
variety of acidic catalysts will convert mercaptans to
thioethers. Additionally, the data show that the antimony
intercalate compound is the preferred catalyst.
EXAMPLE VII
A silica-alumina catalyst was prepared by
binding mordenite zeolite in a gamma alumina binder. The
mordenite content was 90%. The catalyst was evaluated as
previously specified except as follows: 1) sour FCC
gasoline containing 192 wppm mercaptan sulfur; 2) liquid
hourly space velocity = 5; 3) temp - 50C; 4) pressure =
18 atm.; 5) 1.6% isobutylene added. The results indicate
that the mercaptan content was reduced by 20~ through 10
total hours on stream.

~3~S~
EXAMPLE VIII
A new portîon of catalyst A was evaluated
according to the procedure specified hereinbefore, except
for the following: 1) the sour hydrocarbon fraction was
an FCC gasoline containing 355 ppm of mercaptans; 2) the
liquid hourly space velocity (L~SV) was 5: 3) the reactor
temperature was 50C; 4) the pressure was 9.2 atm.; and 5)
13.6% weight percent of isobutylene added. The evaluation
was carried out for forty hours to determine the
durability of the catalyst~ The result of this evaluation
are presented in Figure 1. Figure 1 presents a graph of
the amount of mercaptan left in the treated hydrocarbon
fraction as a function of time. The results indicate that
the catalyst is converting at least 235 ppm (66%~ of the
mercaptans to thioethers for the duration of the test.
EXAMPLE IX
During the evaluation of particular acid
catalysts, it was found that deactivation of the catalyst
was occurring. Extensive tests were performed to
determine the causes of this deactivation and it was
concluded that the acid catalyst can be deactivated by
basic nitrogen compounds found in the sour hydrocarbon
fraction. It was also discovered that an acid wash could
remove most of the basic nitrogen compounds. This example
presents durability results of an acid catalyst ested
with an FCC gasoline that was given an acid wash and an
FCC gasoline that was not given an acid wash.
A portion of an FCC gasoline was given an acid
wash as follows. The acid wash of the FCC gasoline was
performed batchwise with a 10 weight percent solution of
aqueous HCl and an FCC gasoline/H2O volumetric ratio of
4/1. The acid wash removed 67% of the nitrogen compounds
(single-stage extraction) while reducing the thiol content
only slightly from 193 wppm to 171 wppm mercaptan sulfur.

~3~S~
16
This acid washed sour hydrocarbon fraction was treated
using a new portion of catalyst B and the apparatus
described in Example VII. Specifically, the operating
conditions for this experiment were: 1~ LHSV = 5.0; 2)
Reactor temperature = 50C; 3) pressure - 9.2 atm.; and
4) 13.6 weight percent of isobutylene added.
A second portion of the same FCC gasoline was
treated without an acid wash using a new portion of
catalyst, but the same operating conditions as in the
above paragraph. The results from both these experiments
are presented in Figure 2. Figure 2 presents plots of
mercaptan conversion to thioethers versus time on stream.
The plots show that acid washing the sour hydrocarbon
fraction prior to contacting it with the acid catalyst
improves the durability of the catalyst. Thus, an acid
wash is a means to improve the durability of the acid
catalyst.

Dessin représentatif

Désolé, le dessin représentatif concernant le document de brevet no 1300544 est introuvable.

États administratifs

2024-08-01 : Dans le cadre de la transition vers les Brevets de nouvelle génération (BNG), la base de données sur les brevets canadiens (BDBC) contient désormais un Historique d'événement plus détaillé, qui reproduit le Journal des événements de notre nouvelle solution interne.

Veuillez noter que les événements débutant par « Inactive : » se réfèrent à des événements qui ne sont plus utilisés dans notre nouvelle solution interne.

Pour une meilleure compréhension de l'état de la demande ou brevet qui figure sur cette page, la rubrique Mise en garde , et les descriptions de Brevet , Historique d'événement , Taxes périodiques et Historique des paiements devraient être consultées.

Historique d'événement

Description Date
Inactive : Périmé (brevet sous l'ancienne loi) date de péremption possible la plus tardive 2009-05-12
Accordé par délivrance 1992-05-12

Historique d'abandonnement

Il n'y a pas d'historique d'abandonnement

Titulaires au dossier

Les titulaires actuels et antérieures au dossier sont affichés en ordre alphabétique.

Titulaires actuels au dossier
UOP
Titulaires antérieures au dossier
JEFFERY C. BRICKER
TAMOTSU IMAI
Les propriétaires antérieurs qui ne figurent pas dans la liste des « Propriétaires au dossier » apparaîtront dans d'autres documents au dossier.
Documents

Pour visionner les fichiers sélectionnés, entrer le code reCAPTCHA :



Pour visualiser une image, cliquer sur un lien dans la colonne description du document (Temporairement non-disponible). Pour télécharger l'image (les images), cliquer l'une ou plusieurs cases à cocher dans la première colonne et ensuite cliquer sur le bouton "Télécharger sélection en format PDF (archive Zip)" ou le bouton "Télécharger sélection (en un fichier PDF fusionné)".

Liste des documents de brevet publiés et non publiés sur la BDBC .

Si vous avez des difficultés à accéder au contenu, veuillez communiquer avec le Centre de services à la clientèle au 1-866-997-1936, ou envoyer un courriel au Centre de service à la clientèle de l'OPIC.


Description du
Document 
Date
(yyyy-mm-dd) 
Nombre de pages   Taille de l'image (Ko) 
Page couverture 1993-10-29 1 13
Dessins 1993-10-29 2 36
Abrégé 1993-10-29 1 45
Revendications 1993-10-29 2 47
Description 1993-10-29 16 599
Taxes 1997-04-16 1 88
Taxes 1996-04-16 1 66
Taxes 1995-04-20 1 70
Taxes 1994-04-17 1 70