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CN108745375A - A kind of titania-based complex solid catalyst and preparation method thereof preparing allantoin - Google Patents

A kind of titania-based complex solid catalyst and preparation method thereof preparing allantoin Download PDF

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Publication number
CN108745375A
CN108745375A CN201810850013.6A CN201810850013A CN108745375A CN 108745375 A CN108745375 A CN 108745375A CN 201810850013 A CN201810850013 A CN 201810850013A CN 108745375 A CN108745375 A CN 108745375A
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solution
titania
solid catalyst
preparation
ethyl alcohol
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茆振斌
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01JCHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/70Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
    • B01J23/89Catalysts 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
    • B01J23/8933Catalysts 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 also combined with metals, or metal oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
    • B01J23/8953Catalysts 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 also combined with metals, or metal oxides or hydroxides provided for in groups B01J23/02 - B01J23/36 with zinc, cadmium or mercury
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01JCHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J35/00Catalysts, in general, characterised by their form or physical properties
    • B01J35/50Catalysts, in general, characterised by their form or physical properties characterised by their shape or configuration
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07DHETEROCYCLIC COMPOUNDS
    • C07D233/00Heterocyclic compounds containing 1,3-diazole or hydrogenated 1,3-diazole rings, not condensed with other rings
    • C07D233/54Heterocyclic compounds containing 1,3-diazole or hydrogenated 1,3-diazole rings, not condensed with other rings having two double bonds between ring members or between ring members and non-ring members
    • C07D233/66Heterocyclic compounds containing 1,3-diazole or hydrogenated 1,3-diazole rings, not condensed with other rings having two double bonds between ring members or between ring members and non-ring members with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
    • C07D233/88Nitrogen atoms, e.g. allantoin

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

Abstract

The present invention provides a kind of titania-based complex solid catalyst and preparation method thereof preparing allantoin, which includes:1)It carries out butyl titanate, graphene, dimethylformamide, ethyl alcohol to be mixed to form solution A;2)Water, ethyl alcohol and acetic acid are mixed to form solution B;3)Mantoquita, zinc salt, silver salt, water, ethyl alcohol are mixed to form solution C;4)Solution B, solution C are added dropwise in solution A simultaneously, are then allowed to stand, drying and grinding is to obtain powder objects;5)Powder objects are calcined to prepare the titania-based complex solid catalyst of allantoin.The titania-based complex solid catalyst has excellent catalytic effect for the synthesis of allantoin.

Description

A kind of titania-based complex solid catalyst and preparation method thereof preparing allantoin
Technical field
The present invention relates to allantoins, and in particular, to a kind of titania-based complex solid catalyst preparing allantoin And preparation method thereof.
Background technology
Allantoin, English name Allantion, chemical name Allantio are a kind of heavy The fine chemical product wanted, purposes are extremely wide.Allantoin, which has, promotes skin epithelial cell growth, wound healing, analgesic, soft Change the physiological functions such as keratoprotein, and it is nontoxic, non-stimulated, without anaphylaxis, be protected from light, sterilization and anticorrosion, antioxidation, can make Skin keeps moisture content, moistens and soft, thus answers in medicine and Cosmetic Manufacture extensively.In addition, allantoin also has stimulation life The function of object growth, can be used as plant growth regulator in agricultural production, there is solid fruit, accelerate the ripening, increase production and other effects.
Natural allantoin is present in excreta and some plants of certain animals, and certain technique may be used and carried It takes, for example, Chinese patent CN1958575A and CN1861581A are reported respectively from Chinese yam and extracting allantoin in Herba Cistanches, But the problems such as complicated because of the low processing step with involved by of content, almost without practical value for the preparation of allantoin.Therefore, Being all made of chemical synthesis process both at home and abroad prepares allantoin at present.
Existing industrialized production allantoin method mainly uses oxalic acid electrolysis or glyoxal nitric acid oxidation method.Its In, oxalic acid electrolysis raw material is cheap and easy to get, but equipment investment is big, technological process is complicated, high energy consumption.Glyoxal method in two steps into Row, the first step relate to glyoxal through nitric acid oxidation be glyoxalic acid, second step be under the catalytic action of catalyst glyoxalic acid with Urea condensation generates allantoin, yield generally about 40%.Existing catalyst is generally inorganic acid, and inorganic acid is as catalysis On the one hand agent can cause to corrode to equipment, pollute the environment simultaneously;The significantly catalytic effect of strong inorganic acid catalyst It is not very superior, causes the yield of allantoin generally low.
Invention content
The object of the present invention is to provide a kind of titania-based complex solid catalyst preparing allantoin and its preparation sides Method, the titania-based complex solid catalyst have excellent catalytic effect, while the preparation side for the synthesis of allantoin Method has the characteristics that process is simple and raw material is easy to get.
To achieve the goals above, the present invention provides a kind of titania-based complex solid catalyst preparing allantoin Preparation method, including:
1)It carries out butyl titanate, graphene, dimethylformamide, ethyl alcohol to be mixed to form solution A;
2)Water, ethyl alcohol and acetic acid are mixed to form solution B;
3)Mantoquita, zinc salt, silver salt, water, ethyl alcohol are mixed to form solution C;
4)Solution B, solution C are added dropwise in solution A simultaneously, are then allowed to stand, drying and grinding is to obtain powder objects;
5)Powder objects are calcined to prepare the titania-based complex solid catalyst of allantoin.
The present invention also provides a kind of titania-based complex solid catalyst preparing allantoin, this prepares allantoin Titania-based complex solid catalyst is prepared by above-mentioned preparation method.
In the above-mentioned technical solutions, butyl titanate/graphene solution, ethanol solution, metal salt is made in the present invention first Then solution grinds butyl titanate/graphene solution, ethanol solution, metal salt solution progress haptoreaction, standing, drying Mill is finally calcined and titania-based complex solid catalyst is made to obtain powder objects.The titania-based complex solid is urged Agent has excellent catalytic performance for the synthesis of allantoin, and then improves the yield and combined coefficient of allantoin.
Other features and advantages of the present invention will be described in detail in subsequent specific embodiment part.
Specific implementation mode
The specific implementation mode of the present invention is described in detail below.It should be understood that described herein specific The embodiment only description and interpretation present invention, is not intended to limit the present invention.
The present invention provides a kind of preparation methods for the titania-based complex solid catalyst preparing allantoin, including:
1)It carries out butyl titanate, graphene, dimethylformamide, ethyl alcohol to be mixed to form solution A;
2)Water, ethyl alcohol and acetic acid are mixed to form solution B;
3)Mantoquita, zinc salt, silver salt, water, ethyl alcohol are mixed to form solution C;
4)Solution B, solution C are added dropwise in solution A simultaneously, are then allowed to stand, drying and grinding is to obtain powder objects;
5)Powder objects are calcined to prepare the titania-based complex solid catalyst of allantoin.
In the step 1 of the present invention)In, the dosage of each material can in a wide range, but in order to further increase two The catalytic efficiency of titania based complex solid catalyst, it is preferable that in step 1)In, butyl titanate, graphene, dimethyl methyl Amide, ethyl alcohol weight ratio be 20:5-10:40-60:50-70.
In the step 2 of the present invention)In, the dosage of each material can in a wide range, but in order to further increase two The catalytic efficiency of titania based complex solid catalyst, it is preferable that in step 2)In, the weight ratio of water, ethyl alcohol and acetic acid is 5: 20-25:2-3.
In the step 3 of the present invention)In, the dosage of each material can in a wide range, but in order to further increase two The catalytic efficiency of titania based complex solid catalyst, it is preferable that in step 3)In, mantoquita, zinc salt, silver salt, water, ethyl alcohol weight Amount is than being 10:2-4:0.2-0.6:20-26:15-20.
In the step 1 of the present invention)Step 3)In, mixed condition can in a wide range, but in order to further carry The catalytic efficiency of high titania-based complex solid catalyst, it is preferable that in step 1)Step 3)In, mixing meets following item Part:Mixing temperature is 15-35 DEG C, incorporation time 40-60min.
In the step 4 of the present invention)In, the dosage of each material can in a wide range, but in order to further increase two The catalytic efficiency of titania based complex solid catalyst, it is preferable that in step 4)In, solution A, solution B, the volume ratio of solution C It is 100:20-25:8-12.
In the step 4 of the present invention)In, the condition of standing can in a wide range, but in order to further increase dioxy Change the catalytic efficiency of titanium-based complex solid catalyst, it is preferable that in step 4)In, standing meets the following conditions:Dwell temperature is 10-20 DEG C, time of repose 12-24h;Drying meets the following conditions:Drying temperature is 100-110 DEG C, drying time 6- 10h。
In the step 4 of the present invention)In, the type of each material can in a wide range, but in order to further increase two The catalytic efficiency of titania based complex solid catalyst, it is preferable that in step 4)In, mantoquita is selected from copper sulphate, copper chloride, nitric acid At least one of copper;Zinc salt is selected from least one of zinc sulfate, zinc chloride, zinc nitrate;Silver salt is silver nitrate.
In the step 5 of the present invention)In, the condition of calcining can in a wide range, but in order to further increase dioxy Change the catalytic efficiency of titanium-based complex solid catalyst, it is preferable that in step 5)In, it calcines and is:From 15-35 DEG C with 2-2.5 DEG C/ Min is warming up to 300-360 DEG C and keeps the temperature 30-40min, be then warming up to 550-600 DEG C with 1-1.6 DEG C/min and keep the temperature 1-2h.
The present invention also provides a kind of titania-based complex solid catalyst preparing allantoin, this prepares allantoin Titania-based complex solid catalyst is prepared by above-mentioned preparation method.
The present invention will be described in detail by way of examples below.
Embodiment 1
1)By butyl titanate, graphene, dimethylformamide, ethyl alcohol according to 20:8:50:60 weight ratio is mixed(It is mixed It is 25 DEG C to close temperature, incorporation time 50min)Form solution A;
2)By water, ethyl alcohol and acetic acid according to 5:23:2.5 weight ratio mixing(Mixing temperature is 25 DEG C, incorporation time 50min) Form solution B;
3)By mantoquita(Copper sulphate), zinc salt(Zinc sulfate), silver salt(Silver nitrate), water, ethyl alcohol is according to 10:3:0.5:23:18 weight Amount is than mixing(Mixing temperature is 25 DEG C, incorporation time 50min)Form solution C;
4)Solution B, solution C are added dropwise in solution A simultaneously(Solution A, solution B, the volume ratio of solution C are 100:23:10), so After stand(Dwell temperature is 15 DEG C, time of repose 20h), it is dry(Drying temperature is 105 DEG C, drying time 8h), grinding To obtain powder objects;
5)Powder objects are calcined(Be warming up to 330 DEG C with 2.3 DEG C/min from 25 DEG C and keep the temperature 35min, then with 1.3 DEG C/ Min is warming up to 580 DEG C and keeps the temperature 1.5h)Titania-based complex solid catalyst A1 is made.
Embodiment 2
1)By butyl titanate, graphene, dimethylformamide, ethyl alcohol according to 20:5:40:50 weight ratio is mixed(It is mixed It is 15 DEG C to close temperature, incorporation time 60min)Form solution A;
2)By water, ethyl alcohol and acetic acid according to 5:20:2 weight ratio mixing(Mixing temperature is 15 DEG C, incorporation time 60min)Shape At solution B;
3)By mantoquita(Copper chloride), zinc salt(Zinc chloride), silver salt(Silver nitrate), water, ethyl alcohol is according to 10:2:0.2:20:15 weight Amount is than mixing(Mixing temperature is 15 DEG C, incorporation time 60min)Form solution C;
4)Solution B, solution C are added dropwise in solution A simultaneously(Solution A, solution B, the volume ratio of solution C are 100:20:8), so After stand(Dwell temperature is 10 DEG C, and time of repose is for 24 hours), it is dry(Drying temperature is 100 DEG C, drying time 10h), grinding To obtain powder objects;
5)Powder objects are calcined(300 DEG C are warming up to 2 DEG C/min from 15 DEG C and keep the temperature 30min, then with 1 DEG C/min It is warming up to 550 DEG C and keeps the temperature 2h)Titania-based complex solid catalyst A2 is made.
Embodiment 3
1)By butyl titanate, graphene, dimethylformamide, ethyl alcohol according to 20:10:60:70 weight ratio is mixed(It is mixed It is 35 DEG C to close temperature, incorporation time 40min)Form solution A;
2)By water, ethyl alcohol and acetic acid according to 5:25:3 weight ratio mixing(Mixing temperature is 35 DEG C, incorporation time 40min)Shape At solution B;
3)By mantoquita(Copper nitrate), zinc salt(Zinc nitrate), silver salt(Silver nitrate), water, ethyl alcohol is according to 10:4:0.6:26:20 weight Amount is than mixing(Mixing temperature is 35 DEG C, incorporation time 60min)Form solution C;
4)Solution B, solution C are added dropwise in solution A simultaneously(Solution A, solution B, the volume ratio of solution C are 100:25:12), so After stand(Dwell temperature is 20 DEG C, time of repose 12h), it is dry(Drying temperature is 110 DEG C, drying time 6h), grinding To obtain powder objects;
5)Powder objects are calcined(Be warming up to 360 DEG C with 2.5 DEG C/min from 35 DEG C and keep the temperature 40min, then with 1.6 DEG C/ Min is warming up to 600 DEG C and keeps the temperature 1h)Titania-based complex solid catalyst A3 is made.
Comparative example 1
It carries out that titania-based complex solid catalyst B1 is made according to the method for embodiment 1, except that step 1)In not Use graphene.
Comparative example 2
It carries out that titania-based complex solid catalyst B2 is made according to the method for embodiment 1, except that step 1)In not Use mantoquita.
Comparative example 3
It carries out that titania-based complex solid catalyst B3 is made according to the method for embodiment 1, except that step 1)In not Use zinc salt.
Comparative example 4
It carries out that titania-based complex solid catalyst B4 is made according to the method for embodiment 1, except that step 1)In not Use silver salt.
Application examples 1
Above-mentioned titania-based complex solid catalyst, zinc chloride, columbium pentachloride are subjected to immersion 5h in the hydrochloric acid that pH is 3 (Titania-based complex solid catalyst, zinc chloride, columbium pentachloride, hydrochloric acid weight ratio be 20:5:2:70), then dry (Drying temperature is 105 DEG C, drying time 8h)Titanium dioxide base complex/lewis acid composition is made.
By glyoxal and nitric acid according to 1:1.1 molar ratio carries out oxidation reaction(Reaction temperature is 41 DEG C, and the reaction time is 5h)Glyoxalic acid is made, then by glyoxalic acid, urea, titanium dioxide base complex/lewis acid composition according to 1:4: 0.008 molar ratio carries out condensation reaction(Reaction temperature is 75 DEG C, reaction time 4h)Allantoin is made;Final statistics urine The yield of Bursin, concrete outcome are shown in Table 1.
Table 1
Titania-based complex solid catalyst in composition Yield(%)
A1 85
A2 83
A3 79
B1 41
B2 52
B3 79
B4 60
Control group 35
The preferred embodiment of the present invention has been described above in detail, still, the tool during present invention is not limited to the embodiments described above Body details can carry out a variety of simple variants, these letters to technical scheme of the present invention within the scope of the technical concept of the present invention Monotropic type all belongs to the scope of protection of the present invention.
It is further to note that specific technical features described in the above specific embodiments, in not lance In the case of shield, can be combined by any suitable means, in order to avoid unnecessary repetition, the present invention to it is various can The combination of energy no longer separately illustrates.

Claims (7)

1. a kind of preparation method for the titania-based complex solid catalyst preparing allantoin, which is characterized in that including:
1)It carries out butyl titanate, graphene, dimethylformamide, ethyl alcohol to be mixed to form solution A;
2)Water, ethyl alcohol and acetic acid are mixed to form solution B;
3)Mantoquita, zinc salt, silver salt, water, ethyl alcohol are mixed to form solution C;
4)The solution B, solution C are added dropwise in the solution A simultaneously, are then allowed to stand, drying and grinding is to obtain powder objects;
5)The powder objects are calcined so that the titania-based complex solid catalyst for preparing allantoin is made;
Wherein, in step 1)In, the butyl titanate, graphene, dimethylformamide, ethyl alcohol weight ratio be 20:5-10: 40-60:50-70,
In step 2)In, the weight ratio of the water, ethyl alcohol and acetic acid is 5:20-25:2-3,
In step 3)In, the mantoquita, zinc salt, silver salt, water, ethyl alcohol weight ratio be 10:2-4:0.2-0.6:20-26:15- 20。
2. preparation method according to claim 1, wherein in step 1)Step 3)In, the mixing meets following item Part:Mixing temperature is 15-35 DEG C, incorporation time 40-60min.
3. preparation method according to claim 1, wherein in step 4)In, the solution A, solution B, the volume of solution C Than being 100:20-25:8-12.
4. preparation method according to claim 1, wherein in step 4)In, the standing meets the following conditions:Stand temperature Degree is 10-20 DEG C, time of repose 12-24h;The drying meets the following conditions:Drying temperature is 100-110 DEG C, when dry Between be 6-10h.
5. preparation method according to claim 1, wherein in step 4)In, the mantoquita be selected from copper sulphate, copper chloride, At least one of copper nitrate;The zinc salt is selected from least one of zinc sulfate, zinc chloride, zinc nitrate;The silver salt is nitre Sour silver.
6. according to the preparation method described in any one of claim 1-5, wherein in step 5)In, the calcining is:From 15-35 DEG C is warming up to 300-360 DEG C with 2-2.5 DEG C/min and keeps the temperature 30-40min, is then warming up to 550- with 1-1.6 DEG C/min 600 DEG C and keep the temperature 1-2h.
7. a kind of titania-based complex solid catalyst preparing allantoin, which is characterized in that described to prepare the two of allantoin Titania based complex solid catalyst is prepared by the preparation method described in any one of claim 1-6.
CN201810850013.6A 2018-07-28 2018-07-28 A kind of titania-based complex solid catalyst and preparation method thereof preparing allantoin Withdrawn CN108745375A (en)

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Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101347739A (en) * 2007-07-16 2009-01-21 湖南大学 Solid acid catalyst and reaction technique for synthesis of allantoin
JP2010017649A (en) * 2008-07-10 2010-01-28 Tokyo Metropolitan Univ Highly active catalyst and its preparing method

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101347739A (en) * 2007-07-16 2009-01-21 湖南大学 Solid acid catalyst and reaction technique for synthesis of allantoin
JP2010017649A (en) * 2008-07-10 2010-01-28 Tokyo Metropolitan Univ Highly active catalyst and its preparing method

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