WO2016020934A2 - Bimetallic heterogeneous catalyst for use in eco- friendly solvents - Google Patents

Bimetallic heterogeneous catalyst for use in eco- friendly solvents Download PDF

Info

Publication number
WO2016020934A2
WO2016020934A2 PCT/IN2015/000314 IN2015000314W WO2016020934A2 WO 2016020934 A2 WO2016020934 A2 WO 2016020934A2 IN 2015000314 W IN2015000314 W IN 2015000314W WO 2016020934 A2 WO2016020934 A2 WO 2016020934A2
Authority
WO
WIPO (PCT)
Prior art keywords
catalyst
copper
zirconia
palladium
heterogeneous
Prior art date
Application number
PCT/IN2015/000314
Other languages
French (fr)
Other versions
WO2016020934A3 (en
Inventor
Ganapati Dadasaheb Yadav
Saurabh Chandrakant PATANKAR
Original Assignee
Ganapati Dadasaheb Yadav
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
Application filed by Ganapati Dadasaheb Yadav filed Critical Ganapati Dadasaheb Yadav
Publication of WO2016020934A2 publication Critical patent/WO2016020934A2/en
Publication of WO2016020934A3 publication Critical patent/WO2016020934A3/en

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
    • B01J23/89—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with noble metals
    • B01J23/8926—Copper and noble metals
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J35/00—Catalysts, in general, characterised by their form or physical properties
    • B01J35/30—Catalysts, in general, characterised by their form or physical properties characterised by their physical properties
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J35/00—Catalysts, in general, characterised by their form or physical properties
    • B01J35/60—Catalysts, in general, characterised by their form or physical properties characterised by their surface properties or porosity
    • B01J35/61—Surface area
    • B01J35/613—10-100 m2/g
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J35/00—Catalysts, in general, characterised by their form or physical properties
    • B01J35/60—Catalysts, in general, characterised by their form or physical properties characterised by their surface properties or porosity
    • B01J35/63—Pore volume
    • B01J35/633—Pore volume less than 0.5 ml/g
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J35/00—Catalysts, in general, characterised by their form or physical properties
    • B01J35/60—Catalysts, in general, characterised by their form or physical properties characterised by their surface properties or porosity
    • B01J35/64—Pore diameter
    • B01J35/647—2-50 nm
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/02—Impregnation, coating or precipitation
    • B01J37/03—Precipitation; Co-precipitation
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/08—Heat treatment
    • B01J37/082—Decomposition and pyrolysis
    • B01J37/086—Decomposition of an organometallic compound, a metal complex or a metal salt of a carboxylic acid
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
    • C07C29/132—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of an oxygen containing functional group
    • C07C29/136—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of an oxygen containing functional group of >C=O containing groups, e.g. —COOH
    • C07C29/147—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of an oxygen containing functional group of >C=O containing groups, e.g. —COOH of carboxylic acids or derivatives thereof
    • C07C29/149—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of an oxygen containing functional group of >C=O containing groups, e.g. —COOH of carboxylic acids or derivatives thereof with hydrogen or hydrogen-containing gases
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D307/00—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom
    • C07D307/02—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings
    • C07D307/04—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings having no double bonds between ring members or between ring members and non-ring members
    • C07D307/06—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings having no double bonds between ring members or between ring members and non-ring members with only hydrogen atoms or radicals containing only hydrogen and carbon atoms, directly attached to ring carbon atoms
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2523/00—Constitutive chemical elements of heterogeneous catalysts

Definitions

  • the present invention relates to a solid heterogeneous, multi-functional, bimetallic copper and zirconia based catalyst. More specifically, the present invention relates to a heterogeneous, bifunctional catalyst comprising a first catalytic surface including zirconia, which is also a carrier substrate, a second catalytic layer comprising copper, and lastly coating of palladium, with the result that it prevents the leaching of first and second metal catalyst in reaction medium, as well as a process for the preparation of this catalyst.
  • the application of this catalyst is found to be more economic and selective in the reactions such as aldol condensation, Knoevenagel condensation, dehydration, esterification and hydrogenation, wherein water can be used as a solvent which makes the overall reactions economic and environmentally friendly. BACKGROUND OF INVENTION.
  • zirconia-metal catalysts for aldol condensation, Knoevenagel condensation, dehydration, esterification, etc.
  • CN 101648150 discloses the nano-porous palladium metal coppercatalyst The loading of palladium used is much higher. Hence economically is a costly material.
  • the present invention eliminates the drawbacks of the prior art catalysts. It deals with preparation of a heterogeneous and bifunctional palladium- copper supported on zirconia catalyst which comprises of first catalyticsurface includes zirconia, which is also a carrier substrate, a second catalytic layer comprising copper, and lastly coating of palladium obtained by co-precipitation at room temperature using oxalic acid.
  • first catalyticsurface includes zirconia, which is also a carrier substrate, a second catalytic layer comprising copper, and lastly coating of palladium obtained by co-precipitation at room temperature using oxalic acid.
  • the Co-existence of zirconia and Copper in presence of palladium in the active site makes it efficient for reactions such * as aldol condensation, reactions.
  • palladium is in the form of bimetallic complex with eopperand acts as a barrier and prevents the leaching of either of metal in the aqueous medium.
  • the present catalyst helps to use the water as a solvent for catalytic reactions and is recyclable. These advantagesof present catalyst make the reactions easy, economic and environmental friendly. Unlike the prior-art catalysts, no leaching of metal ions into the reaction mixture was observed with the catalyst of the present invention and also it provides high efficacy and selectivity.
  • the primary objective of the present invention aims to provide the bifunctional, bimetallic, heterogeneous zirconia-copper catalyst both the metal catalyst in reaction medium.
  • the present invention also aims to provide method for manufacturing of the bifunctional, bimetallic, heterogeneous zirconia-copper catalyst coupled with palladium.
  • Another object of the present invention is to provide a bimetal catalyst for aldol condensation, Knoevenagel condensation, dehydration, esterification and hydrogenation, wherein organic solvents can be efficiently replaced with water without loss of effectiveness of catalytic activity.
  • One more aspect of the present invention is to prepare tuneable bifunctional, bimetallic, heterogeneous zirconia-copper-palladium catalyst having surface area in the range of 30 m 2 /g to 70m 2 /g, pore volume in the range of0.12 ml/g to 0.25 ml/g and pore diameter in the range of 100 to 270 A 0 .
  • heterogeneous catalyst having surface area in the range of about 30 m 2 /g to 70 m 2 /g, pore volume in the range of about0.12 ml/g to0.25ml/g and pore diameter in the range of about 100 to 270 A 0 , wherein heterogeneous solid catalyst is coated with palladium to prevent the leaching of active catalyst in reaction medium.
  • the heterogeneous solid bimetal catalyst comprises of first catalytic layer includes zirconia, a second catalytic layer comprising copper in the range of 10% to 30% weight of zirconia, and lastly coating of palladium in the range of 0.25% to 1% weight of zirconia.
  • first catalytic layer includes zirconia
  • second catalytic layer comprising copper in the range of 10% to 30% weight of zirconia
  • lastly coating of palladium in the range of 0.25% to 1% weight of zirconia.
  • the copper exists in form of copper oxide and zirconia is tetragonal form. Palladium exists in zero state.
  • the present invention relates to a heterogeneous, bifunctional catalyst comprising of first metal zirconia and second metal copper, Wherein - prevent the leaching of first and second metal catalyst in reaction medium.
  • the tuneable bifunctional heterogeneous, bifunctional catalyst is having surface area in the range of 30 m2/g to 70 m2/g, pore volume in the range - of 0.12 ml/g to 0.25 ml/g and pore diameter in the range of 100 to 270 A 0 .
  • the copper exists in form of copper oxide, zirconia exists in form of tetragonal form and Palladium exists in zero state.
  • the said catalyst comprises of copper loading in the range of 10% to 30% weight of zirconia and palladium loading in the range of 0.25% to 1% weight of zirconia.
  • the present invention relates to a heterogeneous, bifunctional catalyst comprising of first metal zirconia and second metal copper, Wherein zirconia layer is coated with copper-palladium alloy and said palladium present in alloy form act as a barrier for cooper as well as zirconia, with the result that it prevent the leaching of first and second metal catalyst in reaction medium.
  • Palladium is palladium coating wherein Palladium gets structurally integrated in the matrix of Zirconia and copper.
  • a process for the preparation of heterogeneous, bimetal copper-zirconia catalyst comprising the steps of;
  • Figure l:It represents the scanning electron microscopy image of Pd-Cu- Zr0 2 catalyst at magnification of 1000X.
  • Figure 2 Shows the energy dispersive X-Ray spectroscopy of Pd-Cu-Zr0 2 catalyst.
  • Figure 3 Shows the XPS recorded on an ESCA-3 Mark II spectrometer for Pd-Cu-Zr0 2 catalyst with pd-3d peak.
  • Figure 4 Shows the XPS recorded on an ESCA-3 Mark II spectrometer for Pd-Cu-Zr0 2 catalyst with Cu-2d peak..
  • the present invention relates to a solid heterogeneous, bimetallic copper and zirconia based catalyst.
  • the application of this catalyst is found to be more economic and selective in the reactions such as aldol condensation, Knoevenagel condensation, dehydration, esterification and hydrogen ation.
  • the present invention provides a heterogeneous copper and zirconia catalyst comprising of a carrier substrate consisting of zirconia.
  • the carrier substrate Zirconia also act as a metal catalyst for Aldol condensation, Knoevenagel condensation , Dehydration, Esterification.
  • the second catalytic layer of present invention comprising copper which is useful for the catalytic reactions such as hydrogenation and dehydration. isconsisting of palladium coating. . Palladium gets structurally integrated in the matrix of Zirconia and copper and changes the property of catalyst such as leaching metal ions in the aqueous reaction medium.
  • the Palladium exists in its zero state and act as a barrier for cooper as well as zirconia, with the result that it prevent the leaching of first and second n etal catalyst in reaction medium.
  • the heterogeneous solid bimetal catalyst comprises of first catalytic layer includes zirconia, a second catalytic layer comprising copper in the range of 10% to 30% weight of zirconia, and lastly coating of palladium in the range of 0.25% to 1% weight of zirconia.
  • the copper exists in form of copper oxide and zirconia is tetragonal form.
  • the present invention further provides a process for the preparation of heterogeneous, bimetal eopper-zirconia catalyst comprising the steps of;
  • Ethanolic solutions of palladium nitrate, copper nitrate and zirconyl nitrate are mixed together such that the concentration of nitrate solution is not more than 0.1 M.
  • the above solution is precipitated by addition of 20% excess oxalic acid solution at room temperature. temperature range from 200° C to 600°C.
  • the active sites of present catalyst are metal sites from copper and base ' sites as well as acid sites from zirconia.
  • Yet another embodiment of the present invention is that the efficiency of the catalyst in presence of water is checked by employing catalyst for synthesis of 1 ,4-pentanediol and 2-methyl tetrahydrofuran by the said heterogeneous solid catalyst, wherein experimentally it is observed that the bimetallic catalyst coated with palladium prepared as per present invention gave same activity in water medium with change in product distribution.
  • compositions in weight percentage range or in other unit in following conditions:
  • the typical reaction of levulinic acid reduction was carried out in Amar autoclaves reactor of 50ml capacity.
  • the reactor had a PID controller for temperature and pressure control and 45° pitched blade turbine impeller. 3.043 ml of levulinic acid was diluted with 50ml water. A catalyst loading of 0.2 g/ml (0.64g catalyst in each experiment) was used.
  • the reactor was purged with nitrogen first to remove traces of air and then pressurised with hydrogen to 60kg/cm . The temperature was then raised to 200°C.
  • Example 3 Leaching study and Study of reusability of catalyst.
  • the TPD-NH3 study indicates that the palladium loading has no measurable effect on the presence of acid sites while loading of copper increases the number of acid sites significantly.
  • the palladium loading blocks the access to the acidic sites and hence the TPD- NH3 shows lesser chemisorption of probe molecule than monometallic Cu/Zr02 catalyst.
  • XPS of the catalyst samples were recorded on an ESCA-3 Mark II spectrometer (VG Scientific Ltd. England) using ⁇ -Ku radiation (1486.74 eV).
  • pellets of 8 mm were made from powdered samples and placed in ultra high vacuum (LI IV) chamber at 10-9 Torr housing the in the preparation chamber at 10-9 Torr for 5 h in order to desorb any volatile species present on the catalyst.
  • LI IV ultra high vacuum
  • the XPS characterization was done to prove presence of Cu and Pd on the catalyst surface. As depicted in Figure 4 and Figure 3, the Cu-2p and Pd-3d peaks were obtained in the analysis. The figures show an increase in binding energy corresponding to Cu-2p and Pd-3d peaks. The increase in binding energy clearly suggests that Pd-Cu exist in the form of alloy.
  • compositions and/or methods disclosed and claimed herein can be made and executed without undue experimentation in light of the present disclosure. While the compositions and methods of this invention have been described in terms of preferred embodiments, it will be apparent to those of skill in the art that variations may be applied to the compositions and/or methods and in the steps or in the sequence of steps of the method described herein without departing from the concept, spirit and scope of the invention. All such similar substitutes and modifications apparent to those skilled in the art are deemed to be within the spirit, scope and concept of the invention as defined by the appended claims.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Inorganic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Catalysts (AREA)

Abstract

The present invention relates to a solid heterogeneous, multi-functional, bimetallic copper and zirconia based catalyst. More specifically, the present invention relates to a heterogeneous, bifunctional catalyst comprising a copper and zirconia, coated with palladium, with the result that it prevents the leaching of first and second metal catalyst in reaction medium, as well as a process for the preparation of this catalyst. The application of this catalyst is found to be more economic and selective in the reactions such as aldol condensation, Knoevenagel condensation, dehydration, esterification and hydrogenation, wherein the water can be used as a solvent which makes the overall reactions economic and environmental friendly.

Description

"BIMETALLIC HETEROGENEOUS CATALYST FOR USE IN ECO- FRIENDLY SOLVENTS"
FIELD OF INVENTION
The present invention relates to a solid heterogeneous, multi-functional, bimetallic copper and zirconia based catalyst. More specifically, the present invention relates to a heterogeneous, bifunctional catalyst comprising a first catalytic surface including zirconia, which is also a carrier substrate, a second catalytic layer comprising copper, and lastly coating of palladium, with the result that it prevents the leaching of first and second metal catalyst in reaction medium, as well as a process for the preparation of this catalyst. The application of this catalyst is found to be more economic and selective in the reactions such as aldol condensation, Knoevenagel condensation, dehydration, esterification and hydrogenation, wherein water can be used as a solvent which makes the overall reactions economic and environmentally friendly. BACKGROUND OF INVENTION.
There is an increasing world-wide interest in preserving the environment, along with other environmental concerns. One type of pollution caused primarily is by the use of organic solvents in most of the chemical reactions. There are numerous heterogeneous copper and/or zirconia based catalyst that are known in the art. The effectiveness of such catalysts is tested over various experimental parameters.
Moreover, with respect to a catalyst containing copper and zirconia have been extensively employed for the selective catalytic reduction of NOx and for a number of hydrogenation and dehydrogenation reactions.
The research paper on Cu-ZrO2 nanocomposite catalyst for selective hydrogenation of levulinic acid and its ester to γ-valerb lactone by C. V. Rode et. al discuss the Cu-ZrO2 nanocomposite catalyst prepared by co- precipitation method using potassium carbonate. The transformation of alcohols into their corresponding aldehydes or ketones is achieved using Zirconia as a support material. But during the effectiveness testing it is proved that water cannot be used in the above-mentioned processes as a reusability.
It is known to use zirconia-metal catalysts for aldol condensation, Knoevenagel condensation, dehydration, esterification, etc. A method disclosed in research paper of Robert J. Devid et al. for synthesis of methacrylic acid by aldol condensation using zirconia acid-base catalyst, however, in presence of water the catalytic activity as well as the selectivity is reduced.
CN 101648150 discloses the nano-porous palladium metal coppercatalyst The loading of palladium used is much higher. Hence economically is a costly material.
The present invention eliminates the drawbacks of the prior art catalysts. It deals with preparation of a heterogeneous and bifunctional palladium- copper supported on zirconia catalyst which comprises of first catalyticsurface includes zirconia, which is also a carrier substrate, a second catalytic layer comprising copper, and lastly coating of palladium obtained by co-precipitation at room temperature using oxalic acid. The Co-existence of zirconia and Copper in presence of palladium in the active site makes it efficient for reactions such * as aldol condensation, reactions. In addition to that palladium is in the form of bimetallic complex with eopperand acts as a barrier and prevents the leaching of either of metal in the aqueous medium. The present catalyst helps to use the water as a solvent for catalytic reactions and is recyclable. These advantagesof present catalyst make the reactions easy, economic and environmental friendly. Unlike the prior-art catalysts, no leaching of metal ions into the reaction mixture was observed with the catalyst of the present invention and also it provides high efficacy and selectivity.
The discussion of documents, acts, materials, devices, articles and the like is included in this specification solely for the purpose of providing a context for the present invention. It is not suggested or represented that any or all of these matters formed part of the prior art base or were common , general knowledge in the field relevant to the present invention as it existed before the priority date of each claim of this application.
OBJECTIVES OF THE INVENTION
• The primary objective of the present invention aims to provide the bifunctional, bimetallic, heterogeneous zirconia-copper catalyst both the metal catalyst in reaction medium.
• The present invention also aims to provide method for manufacturing of the bifunctional, bimetallic, heterogeneous zirconia-copper catalyst coupled with palladium.
• Another object of the present invention is to provide a bimetal catalyst for aldol condensation, Knoevenagel condensation, dehydration, esterification and hydrogenation, wherein organic solvents can be efficiently replaced with water without loss of effectiveness of catalytic activity.
• Yet another objective is to produce heterogeneous, bimetal catalyst that lowers the cost of manufacturing and provides environmental friendly alternative to conventional catalysts.
• One more aspect of the present invention is to prepare tuneable bifunctional, bimetallic, heterogeneous zirconia-copper-palladium catalyst having surface area in the range of 30 m 2 /g to 70m 2 /g, pore volume in the range of0.12 ml/g to 0.25 ml/g and pore diameter in the range of 100 to 270 A0.
SUMMARY OF THE INVENTION. heterogeneous catalyst having surface area in the range of about 30 m2/g to 70 m2/g, pore volume in the range of about0.12 ml/g to0.25ml/g and pore diameter in the range of about 100 to 270 A0, wherein heterogeneous solid catalyst is coated with palladium to prevent the leaching of active catalyst in reaction medium.
In present invention, the heterogeneous solid bimetal catalyst comprises of first catalytic layer includes zirconia, a second catalytic layer comprising copper in the range of 10% to 30% weight of zirconia, and lastly coating of palladium in the range of 0.25% to 1% weight of zirconia. In the present catalyst, the copper exists in form of copper oxide and zirconia is tetragonal form. Palladium exists in zero state.
In present invention, use of co-precipitation method has given the advantage to the present process of production of catalyst in the form of precipitates and making the resultant structure porous in nature after calcination. The binding of bimetals and palladium is such that it prevents the leaching of metals in medium and further enhancement in activity.
STATEMENT OF INVENTION
The present invention relates to a heterogeneous, bifunctional catalyst comprising of first metal zirconia and second metal copper, Wherein - prevent the leaching of first and second metal catalyst in reaction medium. The tuneable bifunctional heterogeneous, bifunctional catalyst is having surface area in the range of 30 m2/g to 70 m2/g, pore volume in the range - of 0.12 ml/g to 0.25 ml/g and pore diameter in the range of 100 to 270 A0. The copper exists in form of copper oxide, zirconia exists in form of tetragonal form and Palladium exists in zero state.
The said catalyst comprises of copper loading in the range of 10% to 30% weight of zirconia and palladium loading in the range of 0.25% to 1% weight of zirconia.
The present invention relates to a heterogeneous, bifunctional catalyst comprising of first metal zirconia and second metal copper, Wherein zirconia layer is coated with copper-palladium alloy and said palladium present in alloy form act as a barrier for cooper as well as zirconia, with the result that it prevent the leaching of first and second metal catalyst in reaction medium. Palladium is palladium coating wherein Palladium gets structurally integrated in the matrix of Zirconia and copper.
A process for the preparation of heterogeneous, bimetal copper-zirconia catalyst comprising the steps of;
(a) Mixing Ethanolic solutions of palladium nitrate, copper nitrate and zirconyl nitrate together such that the concentration of nitrate solution is not more than 0.1 M. solution at room temperature,
(c) Filtering and calcining precipitate between temperature range from 200° C to 600°C.
BRIEF DESCRIPTION OF DRAWINGS
For a more complete understanding of the features and advantages of the present invention, reference is now made to the detailed description of the invention along with the accompanying, figures and in which:
Figure l:It represents the scanning electron microscopy image of Pd-Cu- Zr02 catalyst at magnification of 1000X.
Figure 2:Shows the energy dispersive X-Ray spectroscopy of Pd-Cu-Zr02 catalyst.
Figure 3: Shows the XPS recorded on an ESCA-3 Mark II spectrometer for Pd-Cu-Zr02 catalyst with pd-3d peak.
Figure 4: Shows the XPS recorded on an ESCA-3 Mark II spectrometer for Pd-Cu-Zr02 catalyst with Cu-2d peak..
DETAILED DESCRIPTION OF THE INVENTION.
While the making and using of various embodiments of the present invention are discussed in detail below, it should be appreciated that the present invention provides many applicable inventive concepts that can be discussed herein are merely illustrative of specific ways to make and use the invention and do not delimit the scope of the invention.
To facilitate the understanding of this invention, a number of terms are defined below. Terms defined herein have meanings as commonly understood by a person of ordinary skill in the areas relevant to the present invention. Terms such as "a", "an" and "the" are not intended to refer to only a singular entity, but include the general class of which a specific example may be used for illustration. The terminology herein is used to
1
describe specific embodiments of the invention, but their usage does not delimit the invention, except as outlined in the claims.
The present invention relates to a solid heterogeneous, bimetallic copper and zirconia based catalyst. The application of this catalyst is found to be more economic and selective in the reactions such as aldol condensation, Knoevenagel condensation, dehydration, esterification and hydrogen ation. The present invention provides a heterogeneous copper and zirconia catalyst comprising of a carrier substrate consisting of zirconia. The carrier substrate Zirconia also act as a metal catalyst for Aldol condensation, Knoevenagel condensation , Dehydration, Esterification. The second catalytic layer of present invention comprising copper which is useful for the catalytic reactions such as hydrogenation and dehydration. isconsisting of palladium coating. . Palladium gets structurally integrated in the matrix of Zirconia and copper and changes the property of catalyst such as leaching metal ions in the aqueous reaction medium.
Hence in the present invention, the Palladium exists in its zero state and act as a barrier for cooper as well as zirconia, with the result that it prevent the leaching of first and second n etal catalyst in reaction medium.
Accordingly second embodiment of present invention, the heterogeneous solid bimetal catalyst comprises of first catalytic layer includes zirconia, a second catalytic layer comprising copper in the range of 10% to 30% weight of zirconia, and lastly coating of palladium in the range of 0.25% to 1% weight of zirconia. In the present catalyst, the copper exists in form of copper oxide and zirconia is tetragonal form.
The present invention further provides a process for the preparation of heterogeneous, bimetal eopper-zirconia catalyst comprising the steps of;
1. Ethanolic solutions of palladium nitrate, copper nitrate and zirconyl nitrate are mixed together such that the concentration of nitrate solution is not more than 0.1 M.
2. The above solution is precipitated by addition of 20% excess oxalic acid solution at room temperature. temperature range from 200° C to 600°C.
The active sites of present catalyst are metal sites from copper and base ' sites as well as acid sites from zirconia.
Yet another embodiment of the present invention is that the efficiency of the catalyst in presence of water is checked by employing catalyst for synthesis of 1 ,4-pentanediol and 2-methyl tetrahydrofuran by the said heterogeneous solid catalyst, wherein experimentally it is observed that the bimetallic catalyst coated with palladium prepared as per present invention gave same activity in water medium with change in product distribution.
The present invention is further described with the help of the following examples, which are given by way of illustration all the parts, percent's and ratios are by weight unless otherwise indicated and therefore should not be construed to limit the scope of the invention in any manner.
EXAMPLES:
Ingredients of composition in weight percentage range or in other unit in following conditions:
Example 1: Preparation of Pd-Cu-Zr02 catalyst
9.38 g Zirconyl nitrate dihydrate, 5.512 g cupric nitrate trihydrate and 0.13 g palladium nitrate dihydrate were dissolved in ethanol. Solution was stirred until precursors completely dissolved. Solution of 20% oxalic acid temperature. A precipitate is filtered off and washed with distilled water and separated by centrifugation. The obtained product was dried in air at 100°C for 6 h and calcined in air at 400°C.
Example 2: Synthesis of 1,4-pentanedioI and 2-methyl tetrahydrofuran
The typical reaction of levulinic acid reduction was carried out in Amar autoclaves reactor of 50ml capacity. The reactor had a PID controller for temperature and pressure control and 45° pitched blade turbine impeller. 3.043 ml of levulinic acid was diluted with 50ml water. A catalyst loading of 0.2 g/ml (0.64g catalyst in each experiment) was used. The reactor was purged with nitrogen first to remove traces of air and then pressurised with hydrogen to 60kg/cm . The temperature was then raised to 200°C.
Figure imgf000013_0001
Table No: 1 tetrahydrofuran, 1,4-PDO- 1,4-pentanediol.
Example 3: Leaching study and Study of reusability of catalyst.
The analysis to determine quantitative leaching of copper was done on Lab India Analytical fully automatic atomic absorption spectrophotometer (AA 8000). Copper is detected at wavelength of 324.75 nm. A calibration plot was made for 1 to 5 ppm copper content. The 24 Hr reaction mixture of levulinic acid reduction and dehydration reaction with water as solvent was subjected to analysis. No copper content was detected in sample.
Figure imgf000014_0001
Where; GVL- -valerolactone, EL- Ethyl levulinate, 2-MTHF- 2-methyl tetrahydrofuran, 1,4-PDO- 1,4-pentanediol.
Example 4: Percentage of Palladium Loading.
The analysis to determine quantitative leaching of copper was done on Lab India Analytical fully automatic atomic absorption spectrophotometer (AA 8000). Copper is detected at wavelength of 324.75 nm. A calibration plot was made for 1 to 5 ppm copper content. The 24 h reaction mixture of levulinic acid reduction and dehydration reaction with water as solvent was subjected to analysis with use of different catalysts. The results indicate the need of 1 % Pd loading for preventing leaching of copper.
Catalyst Quantity of copper leached (ppm)
30% Cu/Zi-O2 ' 30
0.25% Pd^29.75% Cu/ZrO2 2.6
0.5% Pd-29.50 % Cu/ZrO2 0.9
l% Pd-29% Cu/ZrO2 , Not detected
Table 3: Atomic absorption spectroscopy results to detect leaching of copper
The efficacy of 1 %Pd-29%Cu/Zr02 catalyst was tested using ethanol and water as solvents.
In case of ethanol as solvent by-product ethyl levulinate (30%) is formed along with γ-valero lactone (70%). 1 ,4-pentanediol and 2- reaction time.
In case of water as solvent, the formation of ethyl levulinate is eliminated. , The reaction proceeds faster to form γ-valerolactone (70%), 1 ,4-pentanediol (25%) and 2-methyltetrahydrofuran (5%) after 24 h reaction time.
Example 5: Effect of Palladium Loading on acidic side
The TPD-NH3 study indicates that the palladium loading has no measurable effect on the presence of acid sites while loading of copper increases the number of acid sites significantly. In case of bimetallic catalyst, the palladium loading blocks the access to the acidic sites and hence the TPD- NH3 shows lesser chemisorption of probe molecule than monometallic Cu/Zr02 catalyst.
Volume of ammonia
chemisorbed per gram of
Catalyst
catalyst under STP conditions
Figure imgf000016_0001
ZrO2 3.9
Pd/ZrO2 3.9
Cu/Zr02 1 1.52
Pd-Cu/ZrO2 8.71
Table 4: Temperature programmed desorption study using NH3 as probe molecule for various synthesized catalysts Example 6; Surface properties of Catalyst
The surface properties of catalysts suggest that loading of palladium occurs in pores of zirconia in case of Pd/Zr02. Hence the surface area of zirconia decreases after loading of palladium. The average pore size increases marginally while pore volume remains same. Copper is loaded both within pores and outside the surface of zirconia. This is evident from similar surface area of Zr02 and Cu/Zr02. However the average pore size and pore volume of Cu/Zr02 is significantly greater than ZrO2. In case of Pd- Cu/Zr02, loading of palladium in pores of zirconia and in proximity of copper clusters results in low surface area, higher pore size and pore volume.
Textural property
Catalyst Surface area Pore volume
Pore size (nm)
(m2/g) (cm3/g)
ZrO2 62 ~8 07Ϊ2 ~
Pd/Zr02 53 9 0.12
Cu/ZrO2 63 13 0.19
Pd-Cu/ZrO2 40 19 0.18
Table 5: Surface properties of various synthesized catalysts
The energy dispersive X-ray spectroscopy studies prove the theory that the palladium is loaded inside the pores while copper is loaded both inside and outside the surface of zirconia. In case of Pd/Zr02, the surface elemental composition of zirconium is 74.03% which is decreased to 0.69%) in case of
Cu/ZrO2.
Elemental analy sis
Catalyst
Element mass %
Zr 74.03
Pd/ZrO2 Pd 0.56
O 25.41
Zr 0.69
Cu/ZrO2 Cu 79.15
o 20.17
Zr 0.92
Pd 1.74
Pd-Cu/Zr02
Cu 77.29
O 20.04
Table 6: Elemental analysis of various catalysts
Example 8: XPS Characterization of Catalyst
XPS of the catalyst samples were recorded on an ESCA-3 Mark II spectrometer (VG Scientific Ltd. England) using ΛΙ-Ku radiation (1486.74 eV). For XPS analysis, pellets of 8 mm were made from powdered samples and placed in ultra high vacuum (LI IV) chamber at 10-9 Torr housing the in the preparation chamber at 10-9 Torr for 5 h in order to desorb any volatile species present on the catalyst.
The XPS characterization was done to prove presence of Cu and Pd on the catalyst surface. As depicted in Figure 4 and Figure 3, the Cu-2p and Pd-3d peaks were obtained in the analysis. The figures show an increase in binding energy corresponding to Cu-2p and Pd-3d peaks. The increase in binding energy clearly suggests that Pd-Cu exist in the form of alloy.
All of the compositions and/or methods disclosed and claimed herein can be made and executed without undue experimentation in light of the present disclosure. While the compositions and methods of this invention have been described in terms of preferred embodiments, it will be apparent to those of skill in the art that variations may be applied to the compositions and/or methods and in the steps or in the sequence of steps of the method described herein without departing from the concept, spirit and scope of the invention. All such similar substitutes and modifications apparent to those skilled in the art are deemed to be within the spirit, scope and concept of the invention as defined by the appended claims.

Claims

I claim,
1) A heterogeneous, bifunctional catalyst comprising of first metal zirconia and second metal copper, Wherein zirconia layer is coated with copper- palladium alloy with the result that it prevent the leaching of first and second metal catalyst in reaction medium.
2) The heterogeneous, bifunctional catalyst as claimed in claim 1 , wherein said catalyst is having surface area in the range of 30 m2/g to 70 m2/g, pore volume in the range of 0.12 ml/g to 0.25 ml/g and pore diameter in the range of 100 to 270 A0.
3) The heterogeneous, bifunctional catalyst as claimed in claim 1 , wherein percentage of copper loading is in the range of 10% to 30%; weight of zirconia and palladium loading is in the range of 0.25% to 1% weight of zirconia.
4) The heterogeneous, bifunctional catalyst as claimed in claim 1 , wherein copper exists in form of copper oxide, zirconia exists in form of tetragonal form and Palladium exists in zero state. ) A process for the preparation of heterogeneous, bimetal copper-zirconia catalyst of claims 1 to 4 comprising the steps of;
a) Mixing Ethanolic solutions of palladium nitrate, copper nitrate and zirconyl nitrate together such that the concentration of nitrate solution is not more than 0.1 M. ,
b) Precipitating by addition of 20% excess oxalic acid solution to above solution at room temperature.
c) Filtering and calcining precipitate between temperature range from 200° C to 600°C.
PCT/IN2015/000314 2014-08-05 2015-08-05 Bimetallic heterogeneous catalyst for use in eco- friendly solvents WO2016020934A2 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
IN2511MU2014 2014-08-05
IN2511/MUM/2014 2014-08-05

Publications (2)

Publication Number Publication Date
WO2016020934A2 true WO2016020934A2 (en) 2016-02-11
WO2016020934A3 WO2016020934A3 (en) 2016-04-28

Family

ID=55264727

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IN2015/000314 WO2016020934A2 (en) 2014-08-05 2015-08-05 Bimetallic heterogeneous catalyst for use in eco- friendly solvents

Country Status (1)

Country Link
WO (1) WO2016020934A2 (en)

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA2499782A1 (en) * 2005-03-07 2006-09-07 Queen's University At Kingston Sol gel functionalized silicate catalyst and scavenger
JP4840584B2 (en) * 2006-03-02 2011-12-21 独立行政法人科学技術振興機構 Polysilane-supported transition metal catalysts for organic synthesis reactions
WO2011006667A2 (en) * 2009-07-17 2011-01-20 Technische Universität Graz Non-leaching heterogeneous catalyst systems for coupling reactions
IN2012DE00662A (en) * 2012-03-07 2015-08-21 Council Scient Ind Res

Also Published As

Publication number Publication date
WO2016020934A3 (en) 2016-04-28

Similar Documents

Publication Publication Date Title
Lee et al. How Pt interacts with CeO2 under the reducing and oxidizing environments at elevated temperature: the origin of improved thermal stability of Pt/CeO2 compared to CeO2
RU2744761C2 (en) Epoxidation method
Mortazavi-Derazkola et al. Facile hydrothermal and novel preparation of nanostructured Ho2O3 for photodegradation of eriochrome black T dye as water pollutant
Okumura et al. A career in catalysis: Masatake Haruta
Kumar et al. Synthesis, characterization and performance of porous Sr (II)-added ZnAl2O4 nanomaterials for optical and catalytic applications
Miedziak et al. Base-free glucose oxidation using air with supported gold catalysts
Liu et al. Catalytic oxidation of toluene over a porous Co 3 O 4-supported ruthenium catalyst
Skrzyńska et al. Performance of Ag/Al 2 O 3 catalysts in the liquid phase oxidation of glycerol–effect of preparation method and reaction conditions
Conesa et al. Comparative study of Cu, Ag and Ag-Cu catalysts over graphite in the ethanol dehydrogenation reaction: Catalytic activity, deactivation and regeneration
JPWO2009022544A1 (en) Catalyst for producing carboxylic acid ester, method for producing the same, and method for producing carboxylic acid ester
Cai et al. Promoting effect of zirconium oxide on Cu–Al 2 O 3 catalyst for the hydrogenolysis of glycerol to 1, 2-propanediol
Fonseca et al. Ceria-zirconia supported Au as highly active low temperature Water-gas shift catalysts
Kibis et al. In situ probing of Pt/TiO 2 activity in low-temperature ammonia oxidation
Gu et al. Efficient transfer hydrogenation of biomass derived furfural and levulinic acid via magnetic zirconium nanoparticles: Experimental and kinetic study
Li et al. Unraveling the mechanisms of room-temperature catalytic degradation of indoor formaldehyde and its biocompatibility on colloidal TiO 2-supported MnO x–CeO 2
CN110201680B (en) Catalyst for selective hydrogenation of alpha, beta-unsaturated aldehyde/ketone, preparation method and catalysis method
Yu et al. Selective deposition of cobalt and copper oxides on BiVO4 facets for enhancement of CO2 photocatalytic reduction to hydrocarbons
Mistri et al. Selective liquid phase benzyl alcohol oxidation over Cu-loaded LaFeO 3 perovskite
US20200276564A1 (en) Methods of preparing metal / metal oxide materials from nanostructured substrates and uses thereof
Sádaba et al. Preparation and characterization of Mg‐Zr mixed oxide aerogels and their application as aldol condensation catalysts
Qin et al. Catalytic oxidation of ethyl acetate over LaBO 3 (B= Co, Mn, Ni, Fe) perovskites supported silver catalysts
Sproge et al. Selective liquid phase oxidation of glycerol to glyceric acid over novel supported Pt catalysts
Durán-Martín et al. Deactivation of CuZn catalysts used in glycerol hydrogenolysis to obtain 1, 2-propanediol
Ampelli et al. A comparative catalyst evaluation for the selective oxidative esterification of furfural
Reddy et al. Selective aerobic oxidation of vanillyl alcohol to vanillin catalysed by nanostructured Ce-Zr-O solid solutions

Legal Events

Date Code Title Description
NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 15830324

Country of ref document: EP

Kind code of ref document: A2