CN105536832B - The preparation method of mesoporous phosphate niobium catalyst and its application in sorbierite isobide - Google Patents
The preparation method of mesoporous phosphate niobium catalyst and its application in sorbierite isobide Download PDFInfo
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- CN105536832B CN105536832B CN201510918916.XA CN201510918916A CN105536832B CN 105536832 B CN105536832 B CN 105536832B CN 201510918916 A CN201510918916 A CN 201510918916A CN 105536832 B CN105536832 B CN 105536832B
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- isobide
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- 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
- B01J27/00—Catalysts comprising the elements or compounds of halogens, sulfur, selenium, tellurium, phosphorus or nitrogen; Catalysts comprising carbon compounds
- B01J27/14—Phosphorus; Compounds thereof
- B01J27/186—Phosphorus; Compounds thereof with arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
- B01J27/195—Phosphorus; Compounds thereof with arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium with vanadium, niobium or tantalum
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- C07D—HETEROCYCLIC COMPOUNDS
- C07D493/00—Heterocyclic compounds containing oxygen atoms as the only ring hetero atoms in the condensed system
- C07D493/02—Heterocyclic compounds containing oxygen atoms as the only ring hetero atoms in the condensed system in which the condensed system contains two hetero rings
- C07D493/04—Ortho-condensed systems
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Abstract
The invention discloses a kind of preparation method of mesoporous phosphate niobium catalyst and its application in sorbierite isobide.The mesoporous phosphate niobium catalyst synthesized using soft template surface active agent assisting alcohol-hydrothermal method, and sorbierite dehydration can be carried out at a lower temperature using the catalyst, the conversion ratio of sorbierite is up to 100%, and the selectivity of isobide is more than 50%.The catalyst has the advantages that stability is good, is easily-synthesized, is renewable, sour amount is controllable.
Description
Technical field
The present invention relates to the preparation of mesoporous phosphate niobium catalyst and the application in sorbierite isobide.Belong to catalysis
Chemistry and field of chemical engineering.It is related to the intersection of biomass energy, nano material and catalytic chemistry and integrates, is both to biology
Matter utilization of resources field is widened, and the transformation to traditional catalyst, to the nano effect essence in heterogeneous catalytic reaction
Further investigation.
Background technology
The characteristics of biomass is due to its recyclability, aboundresources and highly functionalized, turn into 21st century catalysis
The focus of area research.Research both domestic and external lays particular emphasis on catalyzed conversion biomass and its derivative preparing liquid fuel at present and height is attached
Value added chemicals.Analyzed from Atom economy, synthesize bulk chemical and fine chemicals is this again to making full use of biomass
Production-goods source tool is of great significance.
Isobide (isosorbide) is important biomass-based material, is widely used in medicine, surfactant, modeling
The field such as material and polymer.Isobide is the anhydro derivatives of D-glucitol, is treatment encephalic supercharging disease in terms of medicine
Excellent depressor and diuretics.Hydroxyl becomes ehter bond after isobide dehydration, and its is fat-soluble to greatly increase, and is inhaled immediately after oral
Receive, be a kind of oral dehydration and diuresis medicine of effective permeability.Because isobide is not metabolized substantially, it is dehydrated and reduced encephalic
Pressure effect is definite, and pharmacokinetics is simple, better tolerance, and cardiovascular system, kidney and liver function are had no toxic side effect and are used as medicine
Record in American Pharmacopeia and Pharmacopeia of Japan, substituted the intravenous administrations such as mannitol and be widely used in clinic.Isobide is also
For synthesizing antianginal drug Isosorbide Mononitrate and ISDN.
Isobide industrially has special purposes in Material Field because it has chiral centre and rigid structure, extensively
It is general to be applied to the fields such as electronics, national defence.Isobide can be used directly in the isosorbide modified poly- terephthaldehyde of commercial resin
In sour glycol ester (PET), PET hot properties and impact resistance are remarkably improved with isosorbide moieties replacement ethylene glycol,
The solution temperature and crystallinity of polymer are also reduced simultaneously.Isobide also has other in polymer industry in addition to modified PET
Many potential purposes.The 2-glycidyl ether-ether of isobide can substitute bisphenol A epoxide resin, be used as food and beverage
The lashing wire of tank, European Union announce to forbid producing the plastic feeding bottle containing bisphenol-A within the border in European Union from March, 2011.By different mountain
Chiral polyurethane derived from pears alcohol, before there is huge potential pharmacological interest and split the good chemical market of enantiomer
Scape, the copolymer of isobide/Coronex of specific structure can with the excellent optical cable of production performance, be used as engineering plastics or
Person is by controlling arrangement exploitation of the chiral molecules in side chain to have particular characteristic, the suitably new polyesters material of price.
Traditional isobide synthetic route is that the acid catalyzed sorbierite of the liquid such as sulfuric acid, phosphoric acid and P-TOLUENE SULFO ACID 99 is secondary de-
Water reaction, although this homogenous process catalytic efficiency is higher, reaction generates a variety of dehydration accessory substances, and product separation is complicated, easy
Etching apparatus, increase production cost, be unfavorable for heavy industrialization application.Using liquid acid as catalyst dehydration have compared with
High catalytic efficiency, but the harshness that the complexity and catalyst system and catalyzing of homogeneous reaction separation process are required consersion unit, are hindered
The further development of isobide, and the sustainable development policy of green catalysis is run counter to, and the application of solid acid catalyst
Solves this problem, solid acid includes HY, HZSM-5 molecular sieve, acid-exchange resin etc., and solid acid is repeatable with it
Regeneration, equipment corrosion and the features such as environmental pollution is low, reactant and product can be easily separated, turn into acid catalyzed reaction in recent years
The main flow of development, research field are widened increasingly.
The country using sorb alcohol production isobide patent it is few, more it is representational be using montmorillonite, molecular sieve,
Load the sorbierite dehydration on the solid acid catalysts such as phosphoric acid, metal phosphate, carried heteropoly acid, loading metal-salt.On
It is gas-solid reaction to state catalyst, and raw material is sorbitol aqueous solution, and big energy can be consumed when this synthetic method not only vaporizes,
And the acid centre of catalyst is easily lost in and causes catalyst inactivation.
In summary, niobium phosphate solid acid catalyst is applied to sorbierite isobide catalytic field, has no patent report
Road.
The content of the invention
The present invention is total to using composite shuttering surfactant PEO-PPOX-PEO three block
Polymers, also referred to as Pluronic, abbreviation P123 (PEO20PPO70PEO20), assisting alcohol-hydrothermal method one-step synthesis has meso-hole structure phosphoric acid
Niobium solid acid catalyst, meso-hole structure niobium phosphate solid acid catalyst are made using the high specific surface area of mesoporous material and pore volume
It has more activated centre (B acid position), improves the catalyst activity and stability, while the catalyst is applied to sorb
Alcohol isobide reaction system, whole reaction is liquid-solid reaction, and energy consumption can be greatly reduced, and improves efficiency.
The technical scheme is that:
A kind of preparation method of mesoporous phosphate niobium catalyst, comprises the following steps:
(1) in NbCl5The aqueous solution in, be added dropwise phosphoric acid, stirring, add NH3·H2O adjusts pH value to 3~6, and filtering is heavy
Form sediment;
(2) precipitation is added in the P123 aqueous solution with phosphoric acid, stirring;
(3) move in hydrothermal reaction kettle, 24~48h is being reacted at 40~80 DEG C;
(4) precipitation is filtered, washs, dried, in 4~8h of Muffle kiln roasting at 300~800 DEG C.
As preferable technical scheme, in the step (1), 20~90min, 300~800r/min of rotating speed are stirred.
As preferable technical scheme, in step (1), the NbCl5It is 1 with phosphoric acid quality ratio:05~1:2, NbCl5Water
The mass percent of solution is 10%.
As preferable technical scheme, in step (2), the precipitation, P123, the mass ratio of phosphoric acid are 1:2:0.01~1:
10:2;The concentration of the P123 aqueous solution is 5-15wt%;Stir 30~60min.
As preferable technical scheme, the mass fraction of the phosphoric acid is 85%.
The present invention also provides the mesoporous phosphate niobium catalyst that above-mentioned preparation method obtains, and the mesoporous phosphate niobium catalyst is
Undefined structure, specific surface area 110m2/g-190m2/ g, particle diameter are 20~40nm.
The present invention also provides application of the above-mentioned mesoporous phosphate niobium catalyst in sorbierite system prepares isobide.
As preferable technical scheme, described application is using the mesoporous niobium phosphate of solid-state as catalyst, with the pure sorb of liquid
Alcohol is that raw material prepares isobide.
As preferable technical scheme, described application is that the liquid pure sorbitol is urged with the mesoporous niobium phosphate of the solid-state
Agent is with mass ratio 2:1~4:1 adds reactor, under nitrogen protection, is heated to 180~250 DEG C, reacts 2-10h, separate
Isobide.
The mesoporous phosphate niobium catalyst crystal formation SEM of preparation is characterized, as shown in Figure 1.As can be seen from Figure 1:Catalyst
Particle diameter has clearly pore structure in 20-40nm.
The mesoporous phosphate niobium catalyst of preparation nitrogen adsorption desorption detection is subjected to, (insertion is bent for nitrogen adsorption desorption curve
Line is the pore size distribution curve calculated by BJH methods) as shown in Figure 2.As can be seen from Figure 2:Typical TypeIV type adsorption desorptions
The formation of curve and hysteresis loop, it was demonstrated that catalyst has meso-hole structure.Most of aperture belongs to macropore range in 2-5nm.
The mesoporous phosphate niobium catalyst of preparation the infrared absorption test of pyridine is subjected to, as shown in figure 4, result display catalysis
Agent has two sour positions:B acid position (1541cm-1Absworption peak), L acid position (1450cm-1Absworption peak).
The mesoporous phosphate niobium catalyst of the present invention is applied to have the following advantages that in the reaction of sorb dehydration of alcohols isobide:
(1) reaction efficiency is higher:Currently used sorb dehydration of alcohols isobide reaction, raw material sorbierite is the aqueous solution
Rather than pure material, this causes tradition to react relatively inefficient;And it is sorbierite using the reaction of mesoporous phosphate niobium catalyst
For pure material, this make it that the reaction efficiency is higher.
(2) energy consumption of reaction is relatively low:Currently used sorb dehydration of alcohols isobide reaction, raw material sorbierite is water-soluble
, it is necessary to be reacted after sorbitol aqueous solution is gasified with solid acid catalyst, this will consume substantial amounts of energy and carry out pre-vaporized original liquid
Material;And it is that sorbierite is pure material and reaction is liquid-solid reaction to apply the reaction of mesoporous phosphate niobium catalyst, the energy of consumption compared with
It is few, so as to which energy consumption is relatively low.
(3) reaction stability is good, should not inactivate.Traditional sorbierite isobide reaction is mainly gas-solid reaction, is had
A large amount of water vapor adsorptions are in the acid centre (B acid position) of catalyst, therefore easily inactivation, the life-span of catalyst are less than 24h, typically existed
6h or so;It is mainly liquid-solid reaction by the reaction of sorbierite isobide and the present invention is using mesoporous niobium phosphate as catalyst, reaction
There is no the participation of water in thing, therefore not easy in inactivation.
Brief description of the drawings
Below in conjunction with the accompanying drawings and embodiment the present invention is further detailed explanation:
The width of accompanying drawing 4 of the present invention,
The mesoporous phosphate niobium catalyst SEM figures of Fig. 1;
The nitrogen adsorption desorption curve of the mesoporous phosphate niobium catalysts of Fig. 2;
The mesoporous niobium phosphates of Fig. 3 urge catalyst stability test result;
The mesoporous niobium phosphates of Fig. 4 urge the infrared absorption figure of catalyst pyridine.
Embodiment
Following non-limiting examples can make one of ordinary skill in the art be more fully understood the present invention, but not with
Any mode limits the present invention.
Embodiment 1
Under magnetic agitation (mixing speed 600r/min), by 3.5g H3PO4Solution (85wt%) is slowly added dropwise into NbCl5It is molten
(4g NbCl in liquid5It is dissolved in 70mL deionized waters), continue to stir 30min.Add NH3·H2O 5, precipitated to pH stable
Filter washing.Gained precipitation adds 10%P123 aqueous solution 20mL, stirs 60min;1.2gNH is added dropwise3·H2After O, moving to liner is
In the stainless steel hydrothermal reaction kettle of polytetrafluoroethylene (PTFE), 24h is reacted at 40 DEG C, then the further crystallization 24h at 75 DEG C.Precipitated
Filter, wash, dry, in Muffle kiln roasting 6h at 450 DEG C, mesoporous phosphate niobium catalyst is made.
Embodiment 2
Under magnetic agitation (mixing speed 600r/min), by 3.5g H3PO4Solution (85wt%) is slowly added dropwise into NbCl5It is molten
(7g NbCl in liquid5With 70mL deionized waters), continue to stir 30min.Add NH3·H2O to pH stable 4, precipitation filtering
Washing.Gained precipitation adds 10%P123 aqueous solution 20mL, and it is the phosphoric acid solution that 2g mass fractions are 85% to add quality, is stirred
30-60min stirs 60min;1.2gNH is added dropwise3·H2After O, move in the stainless steel hydrothermal reaction kettle that liner is polytetrafluoroethylene (PTFE),
48h is reacted at 40 DEG C, then the further crystallization 24h at 45 DEG C.Precipitation filtering, is washed, and is dried, in Muffle furnace at 600 DEG C
Middle roasting 6h, mesoporous phosphate niobium catalyst is made.
The stability test of the catalyst of embodiment 3.
After catalyst prepared by embodiment 1 is dried, secondary response in reactor is rejoined, so circulation five times.Knot
Fruit sees that Fig. 3 analyses understand that after mesoporous phosphate niobium catalyst recycles five times, sorb alcohol conversion and isobide do not have selectively
There is obvious reduction, keep constant, catalyst is without deactivation phenomenom.
Comparative example
Mesoporous phosphate niobium catalyst prepared by embodiment 1, embodiment 2, with Amberlyst-15 catalyst (commercial catalysts
Agent) contrasted.
It is added under 0.4g sorbierites, 0.1g catalysts conditions in 50mL batch (-type) stainless steel cauldrons, 230 DEG C of reactions
4h, reaction solution centrifugation, liquid-like carry out liquid-phase chromatographic analysis.Sorbierite and product isobide use water generation efficient liquid phase
Chromatogram detects, and shows poor (RI) detector temperature:30 DEG C, Shodex SUGAR SH1011 analytical columns, column temperature:75 DEG C, pure water is stream
Dynamic phase (0.5mL/min), measurement result is as follows:
Sorb alcohol conversion 85% under the conditions of Amberlyst-15 catalysts, isobide selectivity 25%;And adopt
With the mesoporous phosphate niobium catalyst of embodiment 1, sorb alcohol conversion 100%, isobide selectivity 47%;And use embodiment
2 mesoporous phosphate niobium catalyst, sorb alcohol conversion 100%, isobide selectivity 52%.
Claims (6)
1. the preparation method of mesoporous phosphate niobium catalyst, comprises the following steps:
(1) in NbCl5In the aqueous solution, phosphoric acid is added dropwise, stirring, adds NH3·H2O adjusts pH value to 3~6, and filtering precipitates;
(2) precipitation is added in PEO-PPOX-PEO triblock copolymer aqueous solution with phosphoric acid,
Stirring;
(3) move in hydrothermal reaction kettle, 24~48h is reacted at 40~80 DEG C;
(4) precipitation is filtered, washs, dried, in 4~8h of Muffle kiln roasting at 300~800 DEG C;
In step (1), the NbCl5It is 1 with phosphoric acid quality ratio:0.5~1:2, NbCl5The mass percent of the aqueous solution is 5-
15%;
In step (2), the precipitation, PEO-PPOX-PEO triblock copolymer, the matter of phosphoric acid
Amount is than being 1:2:0.01~1:10:2;PEO-the PPOX-PEO triblock copolymer the aqueous solution
Concentration be 5-15wt%;Stir 30~60min;
The mesoporous phosphate niobium catalyst is undefined structure, specific surface area 110m2/g-190m2/ g, particle diameter are 20~40nm,
Aperture 2-5nm.
2. preparation method according to claim 1, it is characterised in that in the step (1), stir 20~90min, rotating speed
300~800r/min.
3. preparation method according to claim 1, it is characterised in that the mass fraction of the phosphoric acid is 85%.
4. the mesoporous phosphate niobium catalyst that preparation method described in claim 1-3 any one obtains prepares different sorb in sorbierite
Application in alcohol.
5. application according to claim 4, it is characterised in that using the mesoporous niobium phosphate of solid-state as catalyst, with the pure mountain of liquid
Pears alcohol is that raw material prepares isobide.
6. application according to claim 5, it is characterised in that by the liquid pure sorbitol and the mesoporous phosphoric acid of the solid-state
Niobium is with mass ratio 2:1~4:1 adds reactor, under nitrogen protection, is heated to 180~250 DEG C, reacts 2-10h, separate different
Sorbierite.
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CN107473266B (en) * | 2016-06-08 | 2019-08-16 | 中国石油化工股份有限公司 | A kind of niobium phosphate Porous materials and its preparation method and application |
CN106732701B (en) * | 2017-01-11 | 2020-01-31 | 贵州大学 | solid acid catalyst of iron-doped niobium phosphate |
CN114671883A (en) * | 2022-05-07 | 2022-06-28 | 华东理工大学 | Method for preparing isosorbide by dehydrating sorbitol under catalysis of niobium-based solid acid |
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CN102962085A (en) * | 2011-09-01 | 2013-03-13 | 华东理工大学 | Preparation method of niobium phosphate solid acid catalyst and application in sugar dehydration |
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