Solid base catalyst.

(54) Title: SOLID BASED CATALYST.

(54) Title: SOLID BASE CATALYST.

(57) Summary

The application relates to a solid base catalyst including a vehicle, an organic base, and an inorganic base. Both the inorganic base and the organic base are loaded into the vehicle. The solid base catalyst is especially suitable for the synthesis of 4-aminodiphenylamine (4-ADPA).

(57) Abstract

Provided¡sa solid base catalyst containing porous carrier, and organic base and inorganic base loaded on the carrier. The solid catalyst is particularly suitable for the catalytic synthesis of 4-amino-diphenylamine (4-ADPA).

PATENT TITLE No. 360443

Headlines):

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JIANGSU SINORGCHEM TECHNOLOGY CO., LTD.

Address: 22nd Floor, Yongda International Tower No. 2277, Longyang Road, 201204, Pudong

New Area, Shanghai, PEOPLE'S REPUBLIC OF CHINA

Name: SOLID BASED CATALYST.

Classification:

B01J29 / ^? 0ÍJ ^ / fy; ^ 0JJ {¡T «) 0; $ 01J31 / 06; C07C209 / 36; C07C211 / 54

B0 ^ l2 ^ M> e0 * Jál / 00; BOjil / O^¿ 8/1; B01J31 / 26; B01J31 / 0237;

BO1J§1 / O239; B01J31 / 0254; B0 * B01J37 / 0209; C07C209 / 26;

-WC209 / 36; C07

XINMyIN tHEN;

CIP: CPC:

Inventor (s):

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open, told to e-patéete

Number;

MX / a / 2012/013321

87702.7

Validity: VÉMifeño9 » _t See Date ^ ipientb | ''24 = {^ &amp;^lWieyó Date of E¿cfh | 3ciónrt | de | The patent of referen4l ^ se | ^ | rga with fundáiHeóto eh los

In accordance with year K from the date of presenSe®

Who subscribes to this title * (Official Gazette of the Federation 01/25/2006, 06/05/2009, 06/01/2010, and 12th fractions I and III of the Reglam 07/28/2004 and 09/07/2007 ); articles 1, 3,. Industrial Property (DOF 12/27/1999, rewma faculties in the Deputy Directors General; Departmental Coordinators and other subordinates 07/29/2004, 08/04/2004 and 09/13/2007).

Industrial.

«• and Industrial Property 5/1999, 01/26/2004, 06/16/2005, os 1 ', 3^or fraction V subsection a), 4th of 07/01/200 ?, 07/15/2004, unique to the Mexican Institute of the ^^ °, 3 »and 5th subsection a) of the Agreement that delegates s Regional Offices, Deputy Directors Divisional,. (DOF 12/15/1999, amended on 02/04/2000,

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THE DIVISIONAL DIRECTOR OF PATENTS

NAHANNY CANAL REYES

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MX / 2019/5360

Field of the Invention

SOLID BASED CATALYST

IMPI

MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY

<img file="MX360443B_D0005.tif" />

The application relates to industrial catalysts, and in particular to solid base catalysts.

Background of the Invention

4-aminodiphenylamine that can be used in the production of antidegradant paraphenllenediamine (PPD) for various polymers including rubber that can be produced in various forms including: 1) reacting p-chloronitrobenzene with aniline derivatives in the presence of an acceptor acid to produce 4-4-nitrophenylamine followed by reduction of a nitro group (US Patent No. 4, 187, 248; 4, 683, 332);

2) p-nitrodiphenyl / hydroxylamine hydrogenation (US Patent No. 4, 178, 315; 4, 404, 401); 3) head-to-tail coupling of aniline US Patent No. 4,760,186), 4) reduction of nitrosodiphenylamine produced by the reaction of acetanilide and nitrobenzene in DMSO and 5) a one-step reaction where nitrobenzene enters Hydrogen contact with aniline in the presence of a hydrogenated catalyst, a hydrogenation inhibitor, and an acid catalyst. Currently the preferred commercial production of 4-ADPA is achieved by condensing aniline and nitrobenzene to produce 4-nitrosodiphenylamine (4-NODPA) and 4-nitrodiphenylamine (4-NDPA) which is then subjected to a hydrogenation step to produce 4ADPA ( US Patent No. 5, 117, 063 and 5, 453, 541).

Nitrobenzene and aniline are directly condensed to produce 4-nitrosodiphenylamine (4-NOPDA) and 4-nitrodiphenylamine (4-NDPA) in the presence of a phase transfer catalyst, typically tetramethylammonium hydroxide (TMAH) which is also used as a base. organic. In the process, a small amount of azobenzene, phenazine, and other by-products are produced. 4NDPA and 4-NODPA are catalytically hydrogenated to produce 4-ADPA.

IMPI

The current processes require a large quantity of solutions acü8 ^^ 8Sífi8s ^r Ί OR INDUSTRIAL organic as catalysts. Because tetramethylammonium hydroxide is closely linked to the reaction products after the reaction

<img file="MX360443B_D0006.tif" />

condensation, the TMHA cannot be separated from the products and regenerated in situ. TMAH can only be released after the condensation products, 4-NDPA and 4-NODPA have been hydrogenated to 4-ADPA, thus the organic base catalyst must go through a hydrogenation reaction process. Since the catalyst is somewhat unstable, the organic-based catalyst frequently decomposes during the hydrogenation process and the subsequent concentration and recycling step. Higher temperatures, increased reaction times and a greater amount of catalyst used lead to a greater decomposition of the organic-based catalyst.

The processes for producing 4-ADPA using water soluble transfer phase catalysts also consume a large amount of energy to protect and recycle the catalyst. Aniline condensation and nitrobenzene require a low water content. Although the organic base catalyst can be removed in the condensation reaction after the hydrogenation reaction, the concentration of the catalyst in the phase of the extracted water phase is low. It is even lower in the reaction system after adding methanol to separate the organic and aqueous phases. In order to recycle and reuse the organic-based catalyst, it must be concentrated, requiring the additional use of energy.

Furthermore, current production processes to produce 4-ADPA from aniline and nitrobenzene are unstable. Impurities formed due to the continuous decomposition and reaction of catalyst condensation during the subsequent steps before it can be recycled, reduce efficiency and impede production. The conditions of the reaction system are continuously changing as impurities accumulate and in this way, altering the reaction conditions for condensation, hydrogenation and especially the separation phase.

This is why the process to produce 4-ADPA becomes less predictable and controllable.

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Current processes to produce 4-ADPA require condition ^{r 11}_{D £ LA} property to perform the hydrogenation reaction which ultimately slows down the process to produce 4-ADPA. For example, in order to prevent the condensation catalyst from decomposing during the hydrogenation reaction, the temperature of the hydrogenation reaction should be limited to 90 ° C or less. This requires that a hydrogenation catalyst with high activity at low temperature be employed, usually a noble metal catalyst. Noble metal catalysts are expensive and often require an organic solvent to speed up the reaction. Said solvents will finally have to be recovered from the reaction system and in this way, increase energy costs.

US Patent No. 6, 395, 933 discloses a process for making 4-ADPA by reacting nitrobenzene and substituted aniline at a controlled temperature in the presence of a strong base and phase transfer catalyst. The process results in low production and an increase in side reactions. The process is expensive and also requires an oxidation agent that makes it unsuitable for commercial production.

US Patent No. 6, 495, 723, describes a composition for use in the condensation of aniline and nitrobenzene that decomposes in a solid vehicle, typically zeolite, having internal channels containing a base. The cross-sectional dimensions of the channels provide an environment that improves the selectivity of the reaction such that undesirable by-products such as phenazine or azobenzene are limited.

The internal diameter of the zeolite vehicle described in US6495723 is very small such that the internal channels of the vehicle are quite restrictive. Due to the limited use of the inner surface, any attempt at a regeneration reaction of the organic catalyst would be mainly carried out on the outer surface.

Furthermore, the small diameter of the internal channels of the zeolite prevent high loading values ​​for the organic catalyst. And as such, more catalyst would have to be employed for the condensation reaction in order to maintain high catalytic activity and industrial value.

IMPIí

US Patent Publication No. 2009/0048465 describes a catalraa ^ ort-eono ^ ejd

INDUSTRIAL comprising tetraalkyl ammonium hydroxide, an alkali metal hydroxide or oxide, and a tetraalkyl ammonium salt in aqueous form, which reduces the need for strict control of the amount of protic materials in the condensation reaction. The complex base catalyst also decreases the conversion of tetraalkyl ammonium hydroxide to tetraalkyl ammonium carbonate in this way, reducing the need to replace the catalyst during the reaction.

However, the complex base catalyst is not in the solid phase and thus has yet to be separated, regenerated and recycled.

Thus, in the aniline and nitrobenzene condensation reaction, the current processes for the production of 4-ADPA using an organic base catalyst requires a large amount of catalyst and the need to recycle the catalyst after several reaction steps. Current processes cannot finish quickly, and it also consumes a high amount of energy. Current processes require a greater amount of solvents and consequently, more solvent recycling steps, a greater increase in impurities that lead to a decrease in the efficiency and quality of the processes to produce 4-ADPA.

Brief Description of the Invention

The application is related to a new catalyst that can be used in the production of 4-aminodiphenylamine (4-ADPA). The catalyst can overcome the defects of current catalysts that are difficult to recycle and easily decompose.

The solid base catalyst of the present application includes an organic-based and inorganic-based vehicle. Both the inorganic base and the organic base are loaded into the vehicle, the organic base serves to catalyze the condensation reaction, and the inorganic base serves to regenerate the organic base catalyst. The vehicle can be an inorganic vehicle, such as, for example, alumina, silica, diatomite, molecular sieve and macroporous resin, including ion exchange resin, especially strong basic ion exchange resin. The vehicle has several interior channels and a huge interior surface of

IMPI in such a way that condensation reactions can be carried out ^ # $ g $$ e

INDUSTRIAL

<img file="MX360443B_D0008.tif" />

inside. The interior surface can be loaded with enough inorganic bases to regenerate the organic base without reducing the organic catafenerdora activity. Generalττ general, this vehicle can be loaded with a higher amount of catalyst. This allows the solid base catalyst of the present application to maintain a higher activity, and requires less catalyst for the condensation of the same amount of reagents compared to a zeolite-loaded catalyst.

The present application includes methods for making solid base catalysts where the organic base is polymerized with a vehicle to produce a vehicle containing an organic base and the vehicle containing the organic base is reacted with an aqueous solution of an inorganic base to produce a solid base catalyst.

The present application also includes methods for making 4- ADPA where aniline and nitrobenzene are condensed in the presence of solid base catalyst to produce 4-nitrosodiphenylamine and 4- nitrodiphenylamine which are subsequently hydrogenated to produce 4-aminodiphenylamine. 4- ADPA synthesizing methods using the process of the present application do not require that the condensation catalyst be recycled.

The solid base catalyst of the present application does not need to be recovered, concentrated or recycled, and thus, a process is provided to produce 4-ADPA that is more efficient, predictable, faster, less expensive and more environmentally friendly. . When the solid base catalyst of the present invention is employed in the process to produce 4-ADPA, the amount of organic base catalyst will be significantly reduced, and also the air pollution caused by decomposition of the organic base. It has benefits for the environment.

Detailed Description of the Invention

Many vehicles can be used in the present application. It can be an inorganic vehicle, typically it is a vehicle with inorganic polarity, as for

<img file="MX360443B_D0009.tif" />

example activated by alumina, porous silica, diatomite and so ^J PROPERTY OF THE VEHICLE HAS A LARGE SPECIFIC SURFACE AREA, AND A LARGE QUANTIFS? F ^^TOcharged atoms on its surface that combine well with organic alkalis ^ SnajxuuQáaiGos. The vehicle may also be a macroporous adsorption resin, especially a styrene based anion exchange resin. The styrene resins preferably have a particle size of about 0.1 to 5.0. In diameter, a density of about 0.3 to about 1.2 g / ml and an exchange capacity of equal to or greater than 1mmol / g (specific surface area: 200-1000m²/ g, Bore diameter: 0.5-500nm.)

The solid base condensation catalyst comprises dual reactive groups that are used in the condensation reaction. An active group is the catalytic group for condensation which is an organic base that catalyzes the condensation of aniline and nitrobenzene. The organic base can be selected from a group consisting of but not limited to methylamine, ethylamine, cyclohexylamine, and other fatty amines, aniline, phenyl diamine, and other aromatic amines, quaternary ammonium salts, or alkalis such as dodecyl trimethyl ammonium chloride, trimethyl benzyl ammonium, tetramethylammonium chloride, tetramethylammonium bromide, tetraethylammonium hydroxide

Tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, tetramethylammonium hydroxide, benzyl trimethyl hydroxide / ammonium, benzyl triethyl / ammonium hydroxide,

4-dimethylaminopyridine and crown ethers that are phase transfer catalysts. In a preferred inclusion of the present application, the organic base is tetraalkylammonium hydroxide, preferably tetraethylammonium hydroxide.

The other active group is the regeneration group comprising an inorganic base that regenerates the organic base. The inorganic base can be, but is not limited to potassium hydroxide, sodium hydroxide, calcium hydroxide, cesium hydroxide, aluminum hydroxide, sodium methoxide, potassium methoxide, sodium ethoxide, and potassium ethoxide. Since the active component of the catalyst is fixed in the vehicle, the heat resistance and anti-decomposition capacity are improved and its activity is more stable. In the preferred inclusion of the present application, the regenerating inorganic base is potassium hydroxide.

The solid base catalyst used in the reaction of the loJ ^ LsPi X

MEXICAN INSTITUTE effectively catalyze the condensation of aniline with nitrobenzene parer'prod

<img file="MX360443B_D0010.tif" />

the intermediate products, 4-nitrosodiphenylamine and 4-nitrodiphenylamine, as well as other derived products such as azobenzene. 4-NDPA and 4-NODPA are directly hydrogenated to produce 4-ADPA. Derived products such as azobenzene and excess aniline are recycled and results as pre-distillers. The amount of waste material produced during the process with the use of a solid base catalyst of the present application is dramatically reduced.

Methods for making a solid base catalyst include polymerizing the organic base with a vehicle to produce a vehicle containing an organic base. The organic base containing vehicle is reacted with an inorganic base aqueous solution to produce a solid base catalyst of the present application. In a preferred method of making the solid base catalyst, tetraethylammonium hydroxide is polymerized with styrene resin in the presence of water to produce styrene resin containing tetraethylammonium hydroxide. The styrene resin containing the tetraethylammonium hydroxide is reacted with an aqueous solution of potassium hydroxide to produce the solid base catalyst of the present application.

and In a typical application inclusion, strong macroporous base anion exchange resins such as D201, D202 are mixed with an aqueous solution of 'TMAH (20-25 wt%). The weight ratio of the basejpicroporous ion exchange resin; the aqueous solution of TMAH is 1: 0.1-10 preferably 1: 0.5-5, most preferably 1: 0.5-1.0. For example, a 1000 ml four-necked flask. Equipped with a stirrer and a condenser, 200g of D201 resin and 400g of 25% wt% aqueous solution of TMAH / ^ I were added to stir, the mixture was heated and refluxed at the temperature of approximately 50-100 ° C , preferred 70-90 ° C, more preferred 70-80 ° C. the reflux reaction was held for 5-8 hours, preferred 6-7 hours, and ^ The reaction mixture is transferred to a beaker when cooled to room temperature. The resin containing the tetramethylammonium hydroxide is put into a reaction in a reaction flask and 50 wt% of the aqueous solution of potassium hydroxide is added.

Generally, the weight ratio of the resin: aqueous potassium solution = 1: 0.1-5, preferred 1: 0.5-1.

<img file="MX360443B_D0011.tif" />

The reaction mixture is stirred and heated to 5-100 ⁰ C, preferred 10-ñf) ⁰ Γ., Most preferred 30-40^to C. the reflux reaction is maintained for 1-8 hours, preferably 2-3 hours. The mixture is then cooled. After filtration and washing with water, the wet solid base catalyst was slowly heated in an oven at less than 50 ° C until dry.

The dry solid base catalyst is produced containing dual reactive groups.

The condensation reaction of aniline and nitrobenzene can be carried out in a kettle or tower type reactor or fluidized bed or fixed bed reactor where the catalyst can be fixed or free flow in the reaction mixture. The condensation reaction can be performed under any pressure condition including a vacuum, intermittent vacuum, atmospheric pressure, or increased pressure. The condensation reaction can be performed from about 0 ° -105⁰ C.

The use of an organic base as a catalyst in the condensation reaction between aniline and nitrobenzene produces intermediates such as 4-NDPA and 4NDOPA that are complexed with the solid base catalyst. In current methods of producing 4-ADPA the organic base is not released from the complex until 4-NDPA and 4-NDOPA are hydrogenated to 4-ADPA. At this point, the organic base is released and can be recycled. In the compositions and methods of the present application, the inorganic base that is part of the solid base catalyst reacts with 4-NDPA and 4-NDOPA complexed with organic acid and releases 4NDOPA and organic acid such that the acid Organic can catalyze another round of condensation between aniline and nitrobenzene and 4-NDPA and 4-NDOPA can be subjected to the hydrogenation step to produce 4-ADPA.

In this way, the organic base catalyst in the condensation reaction is continuously regenerated and the condensation product is continuously released from the catalyst, and in this way, the condensation catalyst can remain in the condensation reactor without entering the hydrogenation or Separation phase steps, and thus, improves the efficiency of the process as well as providing better control and predictability of 4-ADPA synthesis.

aluMbiícliló ^

MEXICAN INSTITUTE

Furthermore, due to the use of the above vehicles and substantially anhydrous reaction (a small amount during the reaction that will be separated in time), the organic base and the inorganic base are loaded on the surface of the vehicles and it is not easy to precipitate them 5 from the vehicles. Thus, the solid base catalyst of the present application can be used repeatedly with good catalytic efficiency.

Since the organic-based catalyst is not transported into the hydrogenation reaction, this reaction can be carried out over a wider temperature range and thus allow different catalysts to be used under a variety of conditions that can increase the rate of the hydrogenation reaction. The absence of the organic base catalyst in the hydrogenation reaction also reduces the need for solvents. For example, without the presence of an organic-based catalyst in the hydrogenation reaction, a nickel catalyst can be used at elevated temperatures of 50 ⁰ -140⁰ C without solvent.

Because the organic base catalyst is regenerated in the condensation reaction it does not have to be recovered, concentrated or recycled. Furthermore, almost 20 all of the raw materials used in the production of 4-ADPA are converted to desired products without the production of unwanted by-products.

This process is friendly to the environment. In addition to a small amount of water generated during condensation and hydrogenation reactions, only a small amount of residual material is produced during the process. No other 25 material will be emitted including gas emissions.

The process requires less energy consumption. Furthermore, in order to maintain the necessary reaction temperature and distillation and refinement steps for product purification, it is not necessary to heat large quantities of material, or to recover or remove them. If the heat generated in the hydrogenation reaction can be used advantageously for the energy required for the entire process, it will have a lower consumption.

The application is illustrated by the following examples does not limit

MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY

<img file="MX360443B_D0012.tif" />

Examples

Example 1

Process to make a Solid Base Catalyst

Added to a 1000 ml four neck flask. equipped with stirrer and 200g D201 resin condenser and 400g 25 wt% aqueous TMAH solution. While stirring, the mixture was heated and refluxed at a temperature of approximately 75⁰ C. the reflux reaction is maintained for 6 hours. The reflux mixture is set aside once it has been transferred to a beaker when it is cooled to room temperature. The resin containing tetramethyl hydroxide is produced after filtration and washing with water. 200 g of resin containing tetramethyl hydroxide and 200 ml by weight% aqueous potassium hydroxide solution were added to a three neck flask equipped with a stirrer and condenser. While stirring, the mixture was heated and refluxed at a temperature of approximately 50-100 ⁰ C for about 2 hours. The mixture was then cooled. After filtration, the wet solid base catalyst was slowly heated in an oven (less than 50⁰ C, at 0.098 MPA) until dry. The dry solid base catalyst was kept in the desiccator until use.

Example 2

Process to make a solid base catalyst

It was added to a 1000 ml four neck flask, equipped with a stirrer and condenser 300 g of activated alumina (grain diameter 2-35nm, produced by Pingxiang city Tianli Chemical fillings Limited Company) and 400 g 25 weight% of an aqueous solution of TMAH. While stirring, the mixture was heated and refluxed at a temperature of approximately 75⁰ C. the reflux reaction was maintained for 6 hours. The reaction mixture was set aside once it was transferred to a beaker when it cooled to room temperature.

To a 500 ml three neck flask equipped with a stirrer and oeflfite6ieaftoiics «

FROM THE PROPERTY added 200 g of resin containing tetramethylammonium hydroxide and Wó '^TOml 5 wt% of aqueous potassium hydroxide solution. While stirring, the mixture was heated and refluxed at a temperature of approximately 50-100⁰ C for 2 hours. The mixture was cooled. After a filtration process, the wet solid base catalyst was slowly heated in an oven (less than 50⁰ C at 0.098MPA) until dry.

Example 3

Synthesis of 4-ADPA Using a Catalyst

50 g of solid base catalyst prepared according to Example 1 and 150 ml were added to a 500 ml three neck flask equipped with a stirrer and condenser. aniline. The mixture was heated to 75⁰ C and the pressure was maintained at approximately 0.095 Mpa. When the temperature was controlled between 7075^to C, 50 ml was added and the condensation reaction began. The water produced during the reaction of the mixture was separated. Nitrobenzene content was continuously analyzed after being in reaction for 10 hours. The reaction was stopped when less than 1% nitrobenzene was found.

The reaction mixture was filtered to recycle the solid phase and produced 280 ml of condensed liquid.

Liquid analysis confirmed that the nitrobenzene conversion was approximately 99% and the content of 4-NDPA and 4-NDOPA was 18% based on the condensed liquid. A small amount of azobenzene and other by-products were produced in the reaction.

280 ml of the condensed liquid was diluted with 70 ml of water and 5% weight of Raney nickel catalyst were added to the high pressure hydrogenation reactor. In order to ensure the absence of oxygen gas, hydrogen has been passed into the reactor to replace the atmosphere inside. The reaction mixture was heated and the pressure was controlled at approximately 1.5 Mpa. The mixture was heated to approximately 60⁰ C and the agitator opened and the

<img file="MX360443B_D0013.tif" />

hydrogenation reaction. The reaction temperature is maintained and

BE THE PROPERTY for two hours. The reaction was halted when no more gWSWffógei was found to be absorbed.

After the filtration process, the Raney nickel catalyst was recycled. The water phase was separated from the mixture to generate 260 ml of hydrogenation material. Chemical analysis revealed that the reaction conversion was 98%. The content of the final 4-ADPA product was 20%. A small amount of by-products was produced.

The final 4-ADPA product was obtained by distillation or refining after the aniline and by-products of the hydrogenated material were distilled. The recycled aniline as well as the by-products were reused.

Example 4

Synthesis of 4-ADPA using a Fixed Catalyst

g. of solid base catalyst prepared according to Example 2 were packed by 60 mesh screens. 4-ADPA was prepared under the reaction conditions of Example 3. After the reaction, the solid catalyst remained in the reactor.

280 mi were produced. of liquid condensed by the reaction. Chemical analysis revealed that the nitrobenzene conversion was 96%, the content of 4 -NDOPA was 25% based on the condensed liquid. A small amount of azobenzene and other derived products were produced in the reaction. Chemical analysis also revealed that the reaction conversion was 98%. The content of the final base-RT product was 20%. A small amount of by-products was produced.

Example 5

MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY

The catalyst prepared according to Example 1 was applied-fepetidaffiefite for 15 times under the reaction conditions of Example 3, and then the nitrobenzene conversion rate of the fifteenth catalytic condensation reaction was still 98.5%

Example 6

The catalyst prepared according to example 2 was applied repeatedly 15 times under the reaction conditions of example 3 and then the conversion rate of nitrobenzene in reaction number fifteen of catalytic condensation was 68%.

The foregoing is the preferred inclusion of the invention and is not intended to limit the scope of protection of the invention. For those skilled in the art, different variations and changes can be made to the invention. Any modifications, equivalent replacements, improvements and the like within the spirit and principles of the invention fall within the scope of protection of the invention.