U.S. patent application number 12/733074 was filed with the patent office on 2010-09-16 for catalyst composition and process for converting aliphatic oxygenates to aromatics.
This patent application is currently assigned to Saudi Basic Industries Corporation. Invention is credited to Naif Al- Otaibi, Khalid Karim, Syed Zaheer.
Application Number | 20100234658 12/733074 |
Document ID | / |
Family ID | 39247321 |
Filed Date | 2010-09-16 |
United States Patent
Application |
20100234658 |
Kind Code |
A1 |
Karim; Khalid ; et
al. |
September 16, 2010 |
Catalyst Composition and Process For Converting Aliphatic
Oxygenates to Aromatics
Abstract
The invention relates to a novel catalyst composition
La-M/zeolite, which consists essentially of from 0.0001 to 20 mass
% of La (lanthanum); from 0.0001 to 20 mass % of at least one
element M selected from the group consisting of molybdenum (Mo),
cerium (Ce) and caesium (Cs); a zeolite of the 10-ring structure
type; and optionally a binder (mass % based on total catalyst
composition). The invention also relates to the use of the catalyst
composition according to the invention in various reactions, for
examples in making aromatics from aliphatic hydrocarbons or
oxygenated hydrocarbons with good selectivity and activity. The
invention further relates more specifically to a process for
converting a feed stream comprising oxygenated lower aliphatic
hydrocarbon compounds, especially methanol, to a product stream
comprising aromatic hydrocarbons and olefins, especially BTX, which
process comprises a step of contacting said feed with the catalyst
composition according to the invention.
Inventors: |
Karim; Khalid; (Riyadh,
SA) ; Al- Otaibi; Naif; (Riyadh, SA) ; Zaheer;
Syed; (Riyadh, SA) |
Correspondence
Address: |
SABIC AMERICAS, INC.
1600 INDUSTRIAL BLVD.
SUGAR LAND
TX
77478
US
|
Assignee: |
Saudi Basic Industries
Corporation
Riyadh
SA
|
Family ID: |
39247321 |
Appl. No.: |
12/733074 |
Filed: |
August 13, 2008 |
PCT Filed: |
August 13, 2008 |
PCT NO: |
PCT/EP2008/006659 |
371 Date: |
April 7, 2010 |
Current U.S.
Class: |
585/469 ;
502/73 |
Current CPC
Class: |
C07C 2529/48 20130101;
C07C 2529/40 20130101; B01J 29/48 20130101; C07C 1/20 20130101;
B01J 29/46 20130101; C07C 1/20 20130101; B01J 29/405 20130101; Y02P
20/52 20151101; B01J 2229/42 20130101; C07C 15/02 20130101; B01J
29/7057 20130101 |
Class at
Publication: |
585/469 ;
502/73 |
International
Class: |
B01J 29/46 20060101
B01J029/46; B01J 29/40 20060101 B01J029/40; C07C 1/00 20060101
C07C001/00 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 13, 2007 |
EP |
07015872.0 |
Claims
1. A La-M/zeolite catalyst composition comprising of from 0.0001 to
20 mass % of La (lanthanum); from 0.0001 to 20 mass % of at least
one element M selected from the group comprising molybdenum (Mo),
cerium (Ce) and caesium (Cs); a zeolite of the 10-ring structure
type; and optionally a binder (mass % based on total catalyst
composition).
2. The catalyst composition according to claim 1, wherein the
zeolite is a crystalline aluminosilicate.
3. The catalyst composition according to claim 2, wherein the
aluminosilicate is selected from the group consisting of ZSM-5,
ZSM-11, ZSM-23, ZSM-48 and ZSM-57.
4. The catalyst composition according to claim 1 containing 0.01-10
mass % of La.
5. The catalyst composition according to claim 1 containing 0.01-10
mass % of at least one element M selected from the group consisting
of Mo, Ce or Cs.
6. The catalyst composition according to claim 1 containing at
least two elements selected from the group consisting of Mo, Ce,
and Cs.
7. The catalyst composition according to claim 1 further containing
copper (Cu) and/or Zinc (Zn).
8. A process for converting a feed stream comprising oxygenated
C1-C10 aliphatic hydrocarbon compounds to a product stream
comprising aromatic hydrocarbons, which process comprises a step of
contacting said feed with a La-M/zeolite catalyst composition
comprising from 0.0001 to 20 mass % of La (lanthanum); from 0.0001
to 20 mass % of at least one element M selected from the group
consisting of molybdenum (Mo), cerium (Ce) and caesium (Cs); a
zeolite of the 10-ring structure type; and optionally a binder
(mass % based on total catalyst composition).
9. The process according to claim 8, wherein the feed stream
comprises C1-C4 alcohols and/or their derivatives.
10. The process according to claim 8, wherein the feed stream
comprises methanol and/or its derivatives.
11. The process according to claim 8, wherein the feed stream
further comprises C1-C5 hydrocarbons.
12. The process according to claim 8, wherein temperature is from
250 to 750.degree. C., pressure is from atmospheric to 3 MPa, and
WHSV is from 0.1 to 500 h.sup.-1.
13. A La-M/zeolite catalyst composition consisting essentially of
from 0.0001 to 20 mass % of La (lanthanum); from 0.0001 to 20 mass
% of at least one element M selected from the group consisting of
molybdenum (Mo), cerium (Ce) and caesium (Cs); a zeolite of the
10-ring structure type; and optionally a binder (mass % based on
total catalyst composition).
Description
[0001] The invention relates to a catalyst composition comprising a
lanthanum-containing zeolite. The invention also relates to the use
of the catalyst composition according to the invention in various
reactions, for example in making aromatics from oxygenated
aliphatic hydrocarbons. The invention further relates to a process
for converting a feed stream comprising oxygenated lower aliphatic
hydrocarbon compounds to a product stream comprising aromatic
hydrocarbons, which process comprises a step of contacting said
feed with the catalyst composition according to the invention.
[0002] More specifically, the invention relates to a catalyst
composition and a process for converting a feed stream comprising
C1-C4 oxygenates to a product stream comprising C6-C8
aromatics.
[0003] Such a catalyst composition is known from patent publication
U.S. Pat. No. 4,156,698, wherein a feed comprising C1-C4 monohydric
alcohol is converted to a mixture of aliphatic and aromatic
hydrocarbons by contacting said feed with a composite catalyst
consisting of a crystalline aluminosilicate zeolite, for example
ZSM-5, and an aluminium matrix, modified with a mixture of rare
earth metals, including lanthanum (La). A catalyst composition
based on ZSM-5/alumina and containing 0.26 mass % of La is used to
convert a methanol feed into gasoline boiling range hydrocarbons.
Rare-earth modification of the alumina matrix would reduce
decomposition of alcohol into carbon monoxide and hydrogen, and
increase conversion to aromatics.
[0004] Aromatic hydrocarbon compounds like benzene, toluene and
xylenes, together often referred to as BTX, are important building
blocks in nowadays petrochemical industries. The general source of
these compounds traditionally is refining of petroleum. Given the
limitations in fossil petroleum resources, alternative sources for
these aromatics are being developed.
[0005] Aliphatic oxygenates, which can be obtained from various
carbon sources via for example synthesis gas, can be converted into
a mixture containing aromatics like BTX; for which reaction various
catalysts have already been proposed. For example, in U.S. Pat. No.
3,894,103 aromatisation of a lower oxygenate compound like methanol
by contacting with a crystalline aluminosilicate zeolite of
specific constraint index and Si/Al ratio is described. In U.S.
Pat. No. 4,724,270 it is taught that in the conversion of methanol
to hydrocarbon the selectivity to aromatics improves if the acidity
of the crystalline aluminosilicate zeolite of specific constraint
index and Si/Al ratio of at least 12 is reduced by a thermal
treatment of said catalyst.
[0006] U.S. Pat. No. 4,822,939 teaches to use a Ga-containing ZSM-5
type zeolite, having a Si/Al ratio of 5000-35000 before
Ga-exchange, to catalytically convert C1-C4 aliphatic oxygenates
into C2-C5 olefins with improved yields and reduced formation of
C1-C5 paraffin. It is indicated that at least part of the Ga should
be present in the zeolite framework in tetrahedral coordination to
provide Bronsted acid sites, and the zeolite should be
substantially free of aluminium in the framework.
[0007] In WO 03/089135 a pentasil-type aluminosilicate containing
sodium, zinc and a mixture of rare-earth metals including La is
disclosed; this catalyst is used to make a mixture comprising
liquid hydrocarbons from lower aliphatic hydrocarbon oxygenates.
Advantage of said catalyst is indicated to be high yield of
high-octane hydrocarbons with a low aromatics content.
[0008] A steamed La-modified ZSM-5/silica/kaolin catalyst
composition is disclosed in WO 99/51549. This catalyst is used to
make a mixture comprising C2-C4 olefins from methanol; but showed
only 2% methanol conversion.
[0009] A La--Cu/ZSM-5 composition is disclosed in U.S. Pat. No.
6,126,912, and used as catalyst for reducing NO.sub.x to
NO.sub.2.
[0010] U.S. Pat. No. 5,866,741 discloses a La--Mo/betazeolite
composition, which is applied as catalyst in converting C9+
aromatics into C6-C8 aromatics.
[0011] In WO 20005/080532 a La--Mo--Zn/Y-zeolite composition is
disclosed, and shown to be useful as catalyst for converting C6+
hydrocarbons into linear C1-C5 alkanes.
[0012] There is a constant need in industry for catalysts and
processes with improved performance in terms of overall process
economics, and it is an object of the present invention to provide
a new catalyst composition, which catalyst can for example be
applied in a process for converting a feed stream comprising
oxygenated lower aliphatic hydrocarbon compounds to a product
stream comprising relatively high amounts of aromatic hydrocarbons,
especially BTX.
[0013] This object is achieved according to the invention with a
catalyst composition La-M/zeolite, which consists essentially of
from 0.0001 to 20 mass % of La (lanthanum); from 0.0001 to 20 mass
% of at least one element M selected from the group consisting of
molybdenum (Mo), cerium (Ce) and caesium (Cs); a zeolite of the
10-ring structure type; and optionally a binder (mass % based on
total catalyst composition).
[0014] The catalyst composition according to the invention
surprisingly shows high productivity in combination with good
selectivity in converting a feed stream comprising oxygenated lower
aliphatic hydrocarbon compounds to a product stream comprising
aromatic hydrocarbons. The catalyst also has the ability to convert
aliphatics or mixtures of methanol and hydrocarbons to aromatics
with a surprisingly high productivity and selectivity. The catalyst
composition also has a lower cost in terms of metals used to modify
zeolite.
[0015] Within the context of the present invention a zeolite, as
comprised in the catalyst composition, is understood to mean an
aluminosilicate, an aluminophosphate (AlPO) or a
silicoaluminophosphate (SAPO). These inorganic porous materials are
well known to the skilled man. An overview of their characteristics
is for example provided by the chapter on Molecular Sieves in
Kirk-Othmer Encyclopedia of Chemical Technology, Volume 16, p
811-853; in Atlas of Zeolite Framework Types, 5.sup.th edition,
(Elsevier, 2001), and also by above-cited patent publications. The
zeolite in the catalyst composition according to the invention is a
crystalline material with homogeneous pore size and channelling
framework structures, and its pores or channels are characterized
by a 10-ring structure. Such zeolites are also referred to as
medium pore size zeolites, with pore dimensions in the range of
from 5 to 7 .ANG.
Zeolites of the 12-ring structure type, like for example
betazeolite, are also referred to as large pore sized; and those of
the 8-ring structure type are called small pore size zeolites. In
the above cited Altlas of Zeolite Framework Types various zeolites
are listed based on ring structure.
[0016] Preferably, the zeolite is in the so-called hydrogen form,
meaning that its sodium or potassium content is very low,
preferably below 0.1, 0.05, 0.02 or 0.01 mass %; more preferably
presence of sodium is below detection limits.
[0017] Preferably, the zeolite in the catalyst composition
according to the invention is aluminosilicate. Any aluminosilicate
that shows activity in converting aliphatic oxygenates to
aromatics, before modifying with the specific metals of the
invention, may be applied. Aluminosilicate zeolites can be
characterized by the Si/Al ratio of the framework. This ratio may
vary widely in the catalyst composition according to the invention.
Preferably, the Si/Al ratio is from about 5 to 1000, more
preferably from about 8 to 500, or from 10 to 300. Examples of
suitable materials include the ZSM-series, or mixtures thereof.
Preferred materials are those known as ZSM-5, ZSM-11, ZSM-23,
ZSM-48 and ZSM-57.
[0018] Also aluminophosphates of medium pore size can be used as
zeolite, like AlPO-11 or AlPO-41 are used.
[0019] In another preferred embodiment, the zeolite in the catalyst
composition used in the process of the invention is a
silicoaluminophosphate (SAPO). SAPO materials have properties of
both aluminosilicates and aluminophopsphates. Any SAPO of medium
pore size that shows activity in converting aliphatic oxygenates to
aromatics, before modifying with the specific metals of the
invention, may be applied.
[0020] The catalyst composition according to the invention consists
essentially of a specific zeolite containing 0.0001-20 mass % of
lanthanum (La), based on total catalyst composition. A certain
minimum amount of lanthanum is needed to improve selectivity of the
catalyst to form aromatics from aliphatic oxygenates; preferably
the catalyst contains therefore at least 0.001, 0.005, 0.01, 0.05,
0.1, 0.2, 0.5, or even 1 mass % of La. If the zeolite would contain
too high an amount of metal, the pores of the zeolite might become
at least partly clogged, resulting in a masking effect. The
La-content of the catalyst thus preferably at most 15, 10, 8, 6, 5,
or even at most 4 mass %.
[0021] The catalyst composition according to the invention consists
essentially of a specific zeolite containing 0.0001-20 mass % of
lanthanum (La) and from 0.0001 to 20 mass % of at least one element
M selected from the group consisting of molybdenum (Mo), cerium
(Ce) and caesium (Cs), based on total catalyst composition.
Presence of one or more of these elements is found to increase
aromatics production from aliphatic oxygenates. Therefore, the
catalyst preferably contains at least 0.001, 0.005, 0.01, 0.05,
0.1, 0.2, 0.5, or even at least 1 mass % of said elements; but at
most 15, 10, 8, 6, or 5 mass %.
[0022] The La-M/zeolite catalyst composition according to the
invention preferably contains at least two elements selected from
the group consisting of Mo, Ce, and Cs, to further improve
performance in for example methanol conversion to aromatics.
[0023] In a further preferred embodiment, the La-M/zeolite catalyst
composition according to the present invention further contains
copper (Cu) and/or Zinc (Zn) as (a) further element(s) in addition
to the elements M as defined herein; both elements may be present
in the same amounts as indicated above for La and the at least one
element M. Such preferred catalysts according to the invention
include La--Mo--Zn/zeolite and La--Mo--Cu--Zn/zeolite.
[0024] Preferably, total metal content of the La-M/zeolite
composition according to the invention is from 0.1 to 25 mass %, or
from 0.2 to 20 mass %.
[0025] The various metal elements contained in the catalyst
according to the invention may be present in the zeolite structure
as framework or non-framework elements; as counterions in the
zeolite; on its surface, e.g. in the form of metal oxides; or be
present in a combination of these forms.
[0026] The catalyst composition La-M/zeolite according to the
invention as described above can optionally contain a binder; that
is a component that does not negatively affect its catalytic
performance, but mainly serves to provide physical integrity and
mechanical strength to the catalyst particles. A binder may
comprise a support or filler, mainly intended to dilute catalyst
activity; and also binder material, which serves as a glue to hold
the components together; both functions may also be combined in one
material. Such binder is known to a skilled person. Examples of
suitable materials include aluminas, silicas, clays such as kaolin,
or combinations thereof. Preferably the binder, if used, is
silica.
[0027] The catalyst composition according to the invention can be
prepared by suitable methods of preparing and modifying zeolites as
well known to the skilled person; including for example
impregnation, calcination, steam and/or other thermal treatment
steps.
[0028] If the catalyst composition in addition to the modified
zeolite is to contain a binder, such composition can for example be
obtained by mixing the modified zeolite and a binder in a liquid,
and forming the mixture into shapes, like pellets or tablets,
applying methods known to the skilled person.
[0029] The invention also relates to the use of the catalyst
composition according to the invention as a catalyst in various
chemical reactions, for example in making aromatic hydrocarbons
from aliphatic hydrocarbons and/or oxygenated hydrocarbons.
[0030] The invention further relates more specifically to a process
for converting a feed stream comprising oxygenated C1-C10 aliphatic
hydrocarbon compounds to a product stream comprising aromatic
hydrocarbons, which process comprises a step of contacting said
feed with the catalyst composition according to the invention.
[0031] In the process according to the invention any hydrocarbon
feedstock which comprises oxygenated lower aliphatic hydrocarbon
compounds can be used as feed stream. Oxygenated hydrocarbon
compounds are herein defined to include hydrocarbons containing
aliphatic moieties and at least one oxygen atom, such as alcohols;
ethers; carbonyl compounds like aldehydes, ketones, carboxylic
acids.
[0032] Preferably, the oxygenated hydrocarbon compounds contain 1
to about 4 carbon atoms. Suitable oxygenated hydrocarbons include
straight or branched chain alcohols, and their unsaturated
analogues. Examples of such compounds include methanol, ethanol,
iso-propanol, n-propanol, dimethyl ether, diethyl ether, methyl
ethyl ether, formaldehyde, dimethyl ketone, acetic acid, and their
mixtures.
[0033] Preferably, the feed stream in the process according to the
invention comprises C1-C4 alcohols and/or their derivatives, more
preferably the feed comprises methanol and/or its derivatives, like
a methanol/dimethyl ether mixture.
[0034] The feed stream may further contain one or more diluents,
the concentration of which may vary over wide ranges; preferably
diluents form about 10-90 vol % of the feed. Examples of suitable
diluents include helium, nitrogen, carbon dioxide, and water.
[0035] The feed stream may also contain other non-aromatic
hydrocarbons, like paraffins and/or olefins; especially C1-C5
hydrocarbons. In a preferred way of performing the process
according to the invention, the feed stream contains aliphatic
hydrocarbons that are recycled from the product stream, for example
after removing aromatic components, and which are then for example
mixed with an oxygenates containing stream before contacting with
the catalyst composition. The advantage hereof is that a higher
conversion to aromatics is obtained, because the catalyst of the
invention is also active for converting paraffins and olefins to
aromatics.
[0036] The step of contacting the feed stream with the catalyst
composition can be performed in any suitable reactor, as known to a
skilled man, for example in a fixed bed, a fluidized bed, or any
other circulating or moving bed reactor.
[0037] The contacting step may be performed at a temperature range
of about 250 to 750.degree. C. A higher temperature generally
enhances conversion to aromatics, the temperature is therefore
preferably at least about 300, 350, or 400.degree. C. Because
higher temperatures may induce side-reactions or promote
deactivation of the catalyst, the temperature is preferably at most
about 700, 600, or 550.degree. C. The reaction temperature
preferably ranges between 400 to 550.degree. C.
[0038] Suitable pressures to conduct the contacting step are from
about atmospheric to 3 MPa, preferably pressure is below about 2.5,
2.0, 1.5, 1.0 or even below 0.5 MPa.
[0039] The flow rate at which the feed stream is fed to the reactor
may vary widely, but is preferably such that a weight hourly space
velocity (WHSV) results of about 0.1-500 h.sup.-1, more preferably
WHSV is about 0.5-250 h.sup.-1, or 1-100 h.sup.-1. WHSV is the
ratio of the rate at which the feed stream is fed to the reactor
(in weight or mass per hour) divided by the weight of catalyst
composition in said reactor; and is thus inversely related to
contact time.
[0040] The product stream in the process according to the invention
comprises aromatic hydrocarbons, in addition to saturated and
unsaturated aliphatic hydrocarbons, and optionally non-converted
oxygenates.
[0041] In a preferred way of operating the process according to the
invention, yield of aromatics is further increased by feeding the
product stream to a subsequent second reaction step, wherein the
reaction mixture made is contacted with a further catalyst
composition to increase the contents of aromatics, for example by
catalytically converting aliphatic hydrocarbons, especially
olefins, present in the product stream. Suitable further catalysts
include the catalyst composition of the invention, and any
aromatization catalyst mentioned in the prior art.
[0042] The invention will now be further illustrated with below
described experiments.
Comparative Experiment A
[0043] Aluminosilicate ZSM-5 (from Zeolists) was calcined at
550.degree. C. Catalyst particles of 40-60 mesh size were loaded
into a tubular fixed bed reactor for the conversion of methanol.
The reaction was conducted at a temperature of 450.degree. C. and
pressure of 1 atmosphere at a weight hourly space velocity (WHSV)
of 9 h.sup.-1 with respect to methanol feed. Product stream
composition was analysed by standard GC techniques. The results are
summarized in Table 1.
[0044] Catalyst activity is measured as the amount of liquid
organic compounds formed per hour; the amount of liquid organics
being a measure for the amount of aromatic compounds formed.
Further in Table 1 TMB means trimethylbenzenes; E BTX is defined as
the mass % of the total BTX in the product divided by the methanol
conversion (in mass %) and multiplied by 100; .SIGMA. Xylene is
mass % of the total xylenes (m,p,o) in the product divided by
methanol conversion (in mass %), multiplied by 100.
Comparative Experiment B
[0045] ZSM-5 (65%) and alumina Al.sub.2O.sub.3 (35%) were mixed in
water and impregnated with mixture of 1.1% Re.sub.2O.sub.3 and
dried at 120.degree. C. overnight, and then calcined at 550.degree.
C. Catalyst in 40-60 mesh size was loaded into tubular fixed bed
reactor for the conversion of methanol. The reaction was conducted
at a temperature of 450.degree. C. and pressure of 1 atmosphere at
weight hour space velocity (WHSV) of 9 with respect to methanol
feed. The results of test runs are given in table.1
Comparative Experiment C
[0046] A catalyst was prepared by ion-exchange and thermal
treatment of commercially available ZSM-5 aluminosilicate (from
Zeolists), with the desired amount of metals and following known
procedures. 0.6 g of lanthanum nitrate (from Fluka) was dissolved
in 100 g of distilled water and heated at 60-65.degree. C. with
continuous stirring. 10 g of ZSM-5 was added to the lanthanum
nitrate solution and heated at 85.degree. C. for 8 hours in a
closed vessel (about 2 mass % of La added to ZSM-5); then the
material was filtered and washed with 2 litres of hot water. The
resultant catalyst slurry was dried in a closed oven at 120.degree.
C. for 16 hrs. The dried material was subsequently calcined in a
rotary furnace with 1.degree. C. temperature increase per minute to
450.degree. C., and held at that temperature for 6 hrs.
[0047] Catalyst of particle size 40-60 mesh was loaded into a
tubular fixed bed reactor for the conversion of methanol. The
reaction was conducted at a temperature of 450.degree. C. and
pressure of 1 atmosphere at a weight hourly space velocity (WHSV)
of 9 h.sup.-1 with respect to methanol feed; results are given in
Table 1.
Comparative Experiment D
[0048] Catalyst was prepared as in Comparative experiment C, but
now 5 g of lanthanum nitrate was dissolved in 100 g of distilled
water; resulting in about 16 mass % of La added to ZSM-5.
[0049] Methanol conversion reaction was performed as in Comparative
experiment C; results are given in Table 1.
Comparative Experiment E
[0050] Analogously to CE C a La-modified catalyst was prepared
starting from a commercially available beta-zeolite (from
Zeolists).
[0051] Dried and calcined catalyst of 40-60 mesh size and
containing about 2 mass % of La was used for conversion of
methanol, analogous to Comparative experiment C. Table 1 summarizes
the results.
Comparative Experiment F
[0052] A gallium-containing zeolite catalyst was prepared,
following the procedure of U.S. Pat. No. 4,822,939, by first
calcining ZSM-5 (from Zeolists) at 538.degree. C. Then 4 g of
calcined ZSM-5, 8 g of gallium nitrate in hydrated form, and 60 g
of water were put in a teflon bottle, and heated to 150.degree. C.
for 18 hours. The resultant product was washed and changed into
ammonium form, followed by calcination in air.
[0053] Catalyst in 40-60 mesh size was loaded into a tubular fixed
bed reactor for the conversion of methanol. The reaction was
conducted as in Comparative experiment C, and results are
summarized in Table 1.
EXAMPLE 1
[0054] Analogous to CE C a modified ZSM-5 catalyst was prepared,
applying 0.6 g of lanthanum nitrate dissolved in 100 g of distilled
water; and 0.5 g of molybdenum oxide, 0.06 g of zinc oxide and 2.6
g of cupric nitrate trihydrated dissolved in 100 g of water at
85.degree. C. Both solutions were mixed and 10 g of ZSM-5 was added
to this solution and heated at 85.degree. C. for 8 hours in a
closed vessel; resulting in about 2 mass % La, 3 mass % Mo, 0.5
mass % of Zn and 7 mass % of Cu being added to ZSM-5.
[0055] Dried and calcined catalyst was used for conversion of
methanol, analogous to Comparative experiments C and D. Table 1
shows a marked improvement in productivity and BTX selectivity.
EXAMPLE 2
[0056] Catalyst was prepared by ion exchange and thermal treatment
of the commercial available ZSM-5 from Zeolists with the desired
amount of metals. 0.6 g of lanthanum Nitrate (fluka) was dissolved
in 100g of distilled water and heated at 60-65.degree. C. on with
continuous stirring. 0.5 g of molybdenum oxide and 0.06 g of zinc
oxide were dissolved into 100 g of water at 85.degree. C. at Ph 5.
Both solutions were mixed and 10 g of ZSM-5 was added to this
solution and heated at 85.degree. C. for 8 hours in a closed
vessel. This represents about La (2%), Mo (3%), and Zn (0.5%) added
to ZSM-5. Resultant catalyst was filtered and washed with 3 litres
of hot water. The resultant catalyst slurry was dried in a closed
oven at 120.degree. C. for 16 hrs. The dried catalyst was calcined
in rotary furnace with 1.degree. C. temperature increase per minute
till 450.degree. C. and held at 450.degree. C. for 6 hrs.
[0057] Catalyst in 40-60 mesh size was loaded into tubular fixed
bed reactor for the conversion of methanol. The reaction was
conducted at a temperature of 450.degree. C. and pressure of 1
atmosphere at weight hour space velocity (WHSV) of 9 with respect
to methanol feed. The results of test runs are given in table
1.
EXAMPLE 3
[0058] Analogous to Comparative experiment C a catalyst was
prepared by ion exchange and thermal treatment of ZSM-5 (from
Zeolists) with 0.6 g of lanthanum nitrate dissolved in 100 g of
distilled water, and 0.5 g of molybdenum oxide dissolved in 100 g
of water; resulting in about 2 mass % of La and 3 mass % of Mo in
ZSM-5.
[0059] Dried and calcined catalyst of 40-60 mesh size was used for
conversion of methanol, analogous to Comparative experiment C.
Table 1 summarizes the results.
EXAMPLE 4
[0060] Analogous to Comparative experiment C a catalyst was
prepared by ion exchange and thermal treatment of ZSM-5 (from
Zeolists) with 0.6 g of lanthanum nitrate dissolved in 100 g of
distilled water, and 0.7 g of cesium nitrate dissolved in 100 g of
water; resulting in about 2 mass % of La and 4.5 mass % of Cs in
ZSM-5.
[0061] Dried and calcined catalyst of 40-60 mesh size was used for
conversion of methanol, analogous to Comparative experiment C.
Table 1 shows a marked improvement in productivity and BTX
selectivity.
Comparative Experiment G
[0062] Comparative experiment C was repeated, but now a mixed feed
consisting of methanol/ethylene/propylene/N2 (36:7.7:6.3:50) is
reacted over the catalyst at 450.degree. C. and 1 atm, with a total
flow of 65 cc/min The results are presented in Table 2.
Comparative Experiment H
[0063] Comparative experiment F was repeated, but now a feed
consisting of methanol/ethylene/propylene/N2 mixture
(36:7.7:6.3:50) is reacted over the catalyst at 450.degree. C. and
1 atm, and with a total flow of 65 cc/min. Results are given in
Table 2.
EXAMPLE 5
[0064] Example 2 was repeated, but now a feed consisting of a
methanol/ethylene/propylene/N2 mixture (36:7.7:6.3:50) is reacted
over the catalyst at 450.degree. C. and 1 atm, and with a total
flow of 65 cc/min. Results are given in Table 2, and show a
significant improvement in productivity and aromatics selectivity
over La-modified zeolite and Ga-modified zeolite (CE G and H).
TABLE-US-00001 TABLE 1 increment in increment in increment in
increment in productivity .SIGMA. BTX .SIGMA. Xylenes .SIGMA.
Aromatics Productivity relative to .SIGMA. relative to relative to
relative to Methanol (liquid Comparative .SIGMA. Aromatics
Comparative Comparative Comparative Conversion organics) experiment
B BTX .SIGMA. Xylenes (total) TMB experiment B experiment B
experiment B Experiment wt % g/hr % wt % wt % wt % wt % % % %
Comparative 100 1 33 5.95 3.19 8.69 0 42 25 34 experiment A
Comparative 95 0.75 base 4.2 2.55 6.50 0 base base base experiment
B Comparative 100 1.23 64 8.64 4.65 11.75 1.02 45 82 81 experiment
C Comparative 100 0.83 10 7.13 3.68 9.85 0.27 20 44 52 experiment D
Comparative 100 0.43 -57 9.01 5.11 13.0 0.31 52 100 100 experiment
E Comparative 100 0.93 31 7.16 3.61 8.90 0.77 20 42 37 experiment F
Example 1 100 1.35 80 10.15 5.52 13.4 1.83 71 116 106 Example 2 100
1.86 148 13.77 7.98 18.8 2.31 103 212 189 Example 3 100 1.07 42
7.27 4.14 9.85 1.25 22 62 52 Example 4 100 1.32 76 10.63 5.52 12.88
1.03 78 116 98
TABLE-US-00002 TABLE 2 increment in increment in increment in
increment in productivity .SIGMA. BTX .SIGMA. Xylenes .SIGMA.
Aromatics Productivity relative to relative to relative to relative
to Methanol (liquid Comparative .SIGMA. .SIGMA. Comparative
Comparative Comparative Conversion organics) experiment H .SIGMA.
BTX Xylenes Aromatics TMB experiment H experiment H experiment H
Experiment wt % g/hr % wt % wt % wt % wt % % % % Comparative 100
0.56 72 16.36 8.3 21.58 1.75 71 83 129 experiment G Comparative 100
0.32 base 9.54 4.54 12.41 0.76 base base base experiment H Example
5 100 1.26 287 38.92 17.76 48.8 2.79 307 291 293
* * * * *