CATEGORY: TRANSALKYLATION
PATENT
Aromatic transalkylation using UZM-44 aluminosilicate zeolite (UOP)
Publication Number Us8609921 B1
Publication Type Grant
Application Number Us 13/792,667
Publication Date Dec 17, 2013
Inventors
Christopher P. Nicholas, Edwin P. Boldingh, Marc R.
Schreier
Original Assignee
Uop Llc
Abstract
A new family of
aluminosilicate zeolites designated UZM-44 has been synthesized. These zeolites
are represented by the empirical formula NanMm k+TtAl1-xExSiyOz where M represents a metal or metals
from zine, Group 1, Group 2, Group 3 and or the lanthanide series of the
periodic table, “m” is the mole ratio of M to (Al+E), T is the organic
structure directing agent or agents, and E is a framework element such as
gallium. UZM-44 may be used to catalyze a process for the transalkylation of a
feedstream comprising one or more of C7, C9, C10 and
C11+ aromatics to obtain a transalkylation product stream having an
increased concentration of C8 aromatics relative to that of the
feedstream.
FIELD
OF THE INVENTION
This invention relates to a new family of aluminosilicate zeolites designated
UZM-44 as the catalytic composite for aromatic transalkylation reactions. They
are represented by the empirical formula of:
NanMm k+TtAl1-xExSiyOz
where M represents a metal or metals from zinc or Group 1 (IUPAC 1), Group 2
(IUPAC 2), Group 3 (IUPAC 3) or the lanthanide series of the periodic table, T
is the organic directing agent or agents derived from reactants R and Q where R
is an A,Ω-dihalosubstituted alkane such as 1,5-dibromopentane and Q is at least
one neutral amine having 6 or fewer carbon atoms such as 1-methylpyrrolidine. E
is a framework element such as gallium.
BACKGROUND OF THE INVENTION
Zeolites are crystalline aluminosilicate compositions which are microporous and
which are formed from corner sharing AlO2 and SiO2 tetrahedra.
Numerous zeolites, both naturally occurring and synthetically prepared, are
used in various industrial processes. Synthetic zeolites are prepared via
hydrothermal synthesis employing suitable sources of Si, Al and structure
directing agents such as alkali metals, alkaline earth metals, amines, or
organoammonium cations. The structure directing agents reside in the pores of
the zeolite and are largely responsible for the particular structure that is
ultimately formed. These species balance the framework charge associated with
aluminum and can also serve as space fillers. Zeolites are characterized by
having pore openings of uniform dimensions, having a significant ion exchange
capacity, and being capable of reversibly desorbing an adsorbed phase which is
dispersed throughout the internal voids of the crystal without significantly
displacing any atoms which make up the permanent zeolite crystal structure.
Zeolites can be used as catalysts for hydrocarbon conversion reactions, which
can take place on outside surfaces as well as on internal surfaces within the
pore.
A particular zeolite, IM-5, was first disclosed by Benazzi, et al. in 1996
(FR96/12873; WO98/17581) who describe the synthesis of IM-5 from the flexible
dicationic structure directing agent, 1,5-bis(N-methylpyrrolidinium)pentane
dibromide or 1,6-bis(N-methylpyrrolidinium)hexane dibromide in the presence of
sodium. After the structure of IM-5 was solved by Baerlocher et al. (Science,
2007, 315, 113-6), the International Zeolite Structure Commission gave the code
of IMF to this zeolite structure type, see Atlas of Zeolite Framework Types.
The IMF structure type was found to contain three mutually orthogonal sets of
channels in which each channel is defined by a 10-membered ring of
tetrahedrally coordinated atoms, however, connectivity in the third dimension
is interrupted every 2.5 nm, therefore diffusion is somewhat limited. In
addition, multiple different sizes of 10-membered ring channels exist in the
structure.
Applicants have successfully prepared a new family of materials designated
UZM-44. The topology of the materials is similar to that observed for IM-5. The
materials are prepared via the use of a mixture of simple commercially
available structure directing agents, such as 1,5-dibromopentane and
1-methylpyrrolidine. UZM-44 may be used as a catalyst in aromatic
transalkylation reactions.
SUMMARY OF THE INVENTION
As stated, the present invention relates to using a new catalytic composite
comprising a new aluminosilicate zeolite designated UZM-44 in a process for
aromatic transalkylation. Accordingly, one embodiment of the invention is a
material having a three-dimensional framework of at least AlO2 and
SiO2 tetrahedral units and an empirical composition in the as
synthesized and anhydrous basis expressed by an empirical formula of:
NanMm k+TtAl1-xExSiyOz
where “n” is the mole ratio of Na to (Al+E) and has a value from approximately
0.05 to 0.5, M represents at least one metal selected from the group consisting
of zinc, Group 1 (IUPAC 1), Group 2 (IUPAC 2), Group 3 (IUPAC 3), and the
lanthanide series of the periodic table, and any combination thereof, “m” is
the mole ratio of M to (Al+E) and has a value from 0 to 0.5, “k” is the average
charge of the metal or metals M, T is the organic structure directing agent or
agents derived from reactants R and Q where R is an A,Ω-dihalogen substituted
alkane having 5 carbon atoms and Q is at least one neutral monoamine having 6
or fewer carbon atoms, “t” is the mole ratio of N from the organic structure
directing agent or agents to (Al+E) and has a value of from about 0.5 to about
1.5, E is an element selected from the group consisting of gallium, iron, boron
and combinations thereof, “x” is the mole fraction of E and has a value from 0
to about 1.0, “y” is the mole ratio of Si to (Al+E) and varies from greater
than 9 to about 25 and “z” is the mole ratio of 0 to (Al+E) and has a value
determined by the equation:
z=(n+k·m+3+4·y)/2
Another embodiment of the catalytic composite of the invention is a microporous
crystalline zeolite having a three-dimensional framework of at least AlO2 and
SiO2 tetrahedral units and an empirical composition in the as
synthesized and anhydrous basis expressed by an empirical formula of:
NanMm k+TtAl1-xExSiyOz
where “n” is the mole ratio of Na to (Al+E) and has a value from approximately
0.05 to 0.5, M represents a metal or metals from Group 1 (IUPAC 1), Group 2
(IUPAC 2), Group 3 (IUPAC 3), the lanthanide series of the periodic table or
zinc, “m” is the mole ratio of M to (Al+E) and has a value from 0 to 0.5, “k”
is the average charge of the metal or metals M, T is the organic structure
directing agent or agents derived from reactants R and Q where R is an
AP-dihalogen substituted alkane having 5 carbon atoms and Q is at least one
neutral monoamine having 6 or fewer carbon atoms, “t” is the mole ratio of N
from the organic structure directing agent or agents to (Al+E) and has a value
of from 0.5 to 1.5, E is an element selected from the group consisting of
gallium, iron, boron and combinations thereof, “x” is the mole fraction of E
and has a value from 0 to about 1.0, “y” is the mole ratio of Si to (Al+E) and
varies from greater than 9 to about 25 and “z” is the mole ratio of O to (Al+E)
and has a value determined by the equation:
z=(n+k·m+3+4·y)/2
and the zeolite is characterized in that it has the x-ray diffraction pattern
having at least the d-spacings and intensities set forth in Table A. The
zeolite is thermally stable up to a temperature of greater than 600° C. in one
embodiment and at least 800° C. in another embodiment.
The catalytic composite of the invention may be prepared by a process
comprising forming a reaction mixture containing reactive sources of Na, R, Q,
Al, Si and optionally E and/or M and heating the reaction mixture at a
temperature of about 160° C. to about 180° C., or about 165° C. to about 175°
C., for a time sufficient to form the zeolite. The reaction mixture has a
composition expressed in terms of mole ratios of the oxides of:
a-bNa2O:bMn/2O:cRO:dQ:1-eAl2O3
:eE2O3 :fSiO2 :gH2O
where “a” has a value of about 10 to about 30, “b” has a value of 0 to about
30, “c” has a value of about 1 to about 10, “d” has a value of about 2 to about
30, “e” has a value of 0 to about 1.0, “f′ has a value of about 30 to about
100, “g” has a value of about 100 to about 4000. With this number of reactive
reagent sources, many orders of addition can be envisioned. Typically, the aluminum
reagent is dissolved in the sodium hydroxide prior to adding the silica
reagents. Reagents R and Q can be added together or separately in many
different orders of addition.
The invention uses UZM-44 as the catalyst or a catalyst component in a process
for the transalkylation of alkylaromatic hydrocarbons. Accordingly, a broad
embodiment of the present invention is a process for transalkylation of a
feedstream comprising one or more of C7, C9, C10 and
C11+ aromatics to obtain a transalkylation product stream having an
increased concentration of C8 aromatics relative to that of the
feedstream, comprising contacting the feedstream at transalkylation conditions
with a catalyst comprising UZM-44.
Free Full Text Source: https://www.google.com/patents/US8609921?dq=hydrogen+inassignee:uop&hl=en&sa=X&ei=C7rvUo_7FInmyQHx1YCgDw&ved=0CEEQ6AEwAjgU
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