- Effects of pore structure of MgO-templated mesoporous carbon on its supported Pt catalysts for reductive alkylation of p-aminodiphenylamine with methyl isobutyl ketone
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Mesoporous carbon (MC) was prepared by the nano-MgO template method and used as a support for the preparation of a Pt-based reductive alkylation catalyst. N2 physical adsorption-desorption, scanning electron microscopy, transmission electron microscopy and X-ray diffraction were used to characterize the carbon supports and supported Pt catalysts. The effects of the pore structure of the Pt/MC catalyst on its performance for reductive alkylation of p-aminodiphenylamine with methyl isobutyl ketone were investigated. The results show that the surface area and pore structure of the MgO-templated mesoporous carbons can be modulated directionally by varying the size of nano-MgO particles and the MgO/PF mass ratio. The catalytic activity and stability of the catalysts for N-(1,3-dimethylbutyl)-N′-phenyl-p-phenylenediamine synthesis increases with an increase in the pore size of the mesoporous carbons. Complete conversion of p-ADPA and 100% selectivity to 6PPD were obtained over Pt/MC50(1/1) within 4 hours, which could maintain a high catalytic activity after being reused 10 times. The characterization results indicate that there was an obvious decrease in the BET specific surface area, pore volume and Pt specific surface area of all used catalysts compared with the fresh catalysts, and the trend was more obvious with the decrease of catalyst pore size, which should be the primary reason for the degradation of catalytic performance.
- Yu, Wenlong,Yu, Shitao,Ding, Junwei,Cheng, Qiuzhen,Liu, Fusheng
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Read Online
- Synthesis method of antioxidant 6PPD to reduce side reactions
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The present invention belongs to the field of fine chemical technology, relates to a method of continuous synthesis of adhesive antioxidant 6PPD. The patent of the present invention uses a precious metal catalyst to synthesize antioxidant 6PPD on a fixed bed, the precious metal catalyst is loaded into a fixed bed reaction device, nitrogen is filled with 0.1 ~ 0.5MPa pressure and replaces the entire high pressure reactor system, after the reaction system is replaced, the temperature rises, and the flow rate of hydrogen is 0.1 ~ 1L / min. Using 4-aminodiphenylamine and similar organic matter and methyl isobutyl methyl ketone and acetone as raw materials, the synthesis test of the antioxidant 6PPD using a precious metal catalyst was carried out. Compared with the existing precious metal kettle hydrogenation process, it has continuous operation, simple operation, avoids the catalyst loss caused by the use of powder catalyst due to filtration, and can reduce production costs; compared with the existing copper catalyst, due to the improvement of catalyst selectivity, NO MIBC dehydrogenation device can be added, saving energy consumption and having superiority.
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Paragraph 0016; 0018-0019
(2022/03/02)
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- Method for preparation of anti-aging agent 6PPD by using micro-reactor
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The invention discloses a method for preparation of an anti-aging agent 6PPD by using a micro-reactor; a homogeneous solution of p-aminodiphenyl amine and methyl isobutyl ketone and hydrogen gas are subjected to a reaction in a gas-liquid reactor, then are introduced into a solid-liquid reactor and are subjected to a reaction, and the obtained reaction liquid repeats the above operations. Compared with the prior art, the gas-liquid reactor and the solid-liquid reactor are connected in series, the gas-solid-liquid three-phase reaction is performed in a micro-channel, and eventually, the conversion rate of raw materials is improved and the reaction time is shortened. The micro-reactor has the advantages of large specific surface area and strong heat transfer and mass transfer abilities, and enables the reactions to be carried out efficiently; and the reaction temperature, time and material ratio and other conditions can be precisely controlled through the micro-channel reactor, by-products are reduced, and the security is improved.
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Paragraph 0029; 0030; 0031; 0032; 0033; 0034; 0035-0046
(2017/08/25)
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- Tailoring supported palladium sulfide catalysts through H 2-assisted sulfidation with H2S
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Supported palladium sulfide catalysts are of great interest in selective hydrogenation reactions. In this work, "Pd4S", "Pd3S", "Pd16S7" and "PdS" supported on activated carbon were selectively synthesized by tailoring the H2-assisted sulfidation of Pd/C with H2S at 150-750°C, and were characterized by means of XRD, XPS, TEM, HRTEM, EDS, BET and H2-TPR techniques. The results indicated that the sulfidation atmosphere, the sulfidation temperature and the metal-support interaction all played important roles in determining the crystal structure and composition of the PdxSy/C catalysts, which in turn gave different catalytic performances in the synthesis of N-(1,3-dimethylbutyl)-N′- phenyl-p-phenylenediamine (6PPD) by the reductive N-alkylation of aromatic amines. PdS/C showed the highest selectivity (>97%) and stability among all the PdxSy/C catalysts.
- Xu, Wei,Ni, Jun,Zhang, Qunfeng,Feng, Feng,Xiang, Yizhi,Li, Xiaonian
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p. 12811 - 12817
(2013/10/22)
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- IMPROVED PROCESS FOR PREPARING 4-AMINODIPHENYLAMINE
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A process for preparing 4-aminodiphenylamine (4-ADPA) comprising steps of coupling of aniline with nitrobenzene in presence of a suitable base, e.g. tetramethylammonium hydroxide (TMAH), hydrogenation of the coupling mass, phase separation, hydrogenation of azobenzene in the separated organic mass and fractional distillation for 4-ADPA recovery. An improvement in 4-ADPA recovery and a lowering of tar formation are obtained due to azobenzene reduction prior to 4-ADPA isolation. Also a gain in volume productivity of 4-ADPA is obtained by suitably altering the batch cycle time of the coupling reaction.
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- SYNTHESIS SYSTEM, RUBBER CHEMICAL SUBSTANCE FOR TIRES, SYNTHETIC RUBBER FOR TIRES, AND PNEUMATIC TIRE
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The present invention provides a synthesis system that can synthesize aniline and/or styrene efficiently, a synthesis system that can synthesize butadiene (1,3-butadiene) efficiently, a rubber chemical for a tire which is synthesized from the aniline obtained by the synthesis system, a synthetic rubber for a tire which is synthesized from the styrene and/or butadiene obtained by the synthesis systems, and a pneumatic tire produced using the rubber chemical for a tire and/or the synthetic rubber for a tire. The present invention relates to a synthesis system for synthesizing aniline and/or styrene from an alcohol having two or more carbon atoms via an aromatic compound.
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- SULFUR-CONTAINING PALLADIUM-CARBON CATALYST AND METHOD FOR PREPARING AND USING THE SAME
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A sulfur-containing palladium-carbon catalyst prepared by loading palladium on an active carbon, mixing the palladium-carbon catalyst with a solvent to form a slurry, adding a sulfide to the slurry to treat the loaded palladium under a predetermined temperature, and removing liquid and drying to obtain the catalyst. The sulfur-containing palladium-carbon catalyst is suitable for making phenylene diamine rubber antioxidant with improved productivity and selectivity.
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Page/Page column
(2013/04/10)
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- Preparation, structural characterization of a novel egg-shell palladium sulfide catalyst and its application in selective reductive alkylation reaction
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A novel egg-shell Pd-S catalyst with palladium metal as the core and a membrane of palladium sulfide as the surface has been prepared by sulphidizing Pd/C with H2S. This catalyst is effective for the reductive alkylation of p-amino diphenylamine (PADPA) and methylisobutyl ketone (MIBK) to afford N-(1,3-dimethylbutyl)-N′-phenyl-p-phenylenedianine (DBPPD) with conversion up to 99.42% and selectivity to 97.46%. Comparing with the other common palladium sulfide catalysts, the membrane of palladium sulfide on the surface and the core of palladium metal cause the Pd on the surface of the new catalyst in a lower sulfur coordination, which improves its activity. Our result indicates that this new egg-shell Pd-S/C is an efficient hydrogenation catalyst.
- Zhang, Qun Feng,Wu, Jia Chun,Su, Chang,Feng, Feng,Ding, Qiao Ling,Yuan, Zhao Lian,Wang, Hong,Ma, Lei,Lu, Chun Shan,Li, Xiao Nian
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p. 1111 - 1114,4
(2020/08/20)
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- METHOD FOR PRETREATING AND USING COPPER-BASED CATALYST
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Method for pretreating the copper-based catalyst having the steps of dehydrating the copper-based catalyst at an elevated temperature, reducing the dehydrated copper-based catalyst with hydrogen, and passivating the activated copper-based catalyst to obtain a catalyst suitable for N-alkylation. The dehydration and reduction steps may be conducted simultaneously.
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Page/Page column 4
(2013/02/27)
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- Stabilization of polymers with styrenated-p-cresols
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Disclosed herein is a process for the preparation of a mixture of styrenated p-cresol species that is liquid at room temperature and has a viscosity of less than 40,000 cps at 25° C., wherein said process affords 2,6-distyrenated p-cresol assaying at 70% minimum by GC area percent, comprising reacting styrene with p-cresol at a molar ratio of 1.85 to 2.1:1, respectively, in the presence of an acid catalyst at elevated temperature, wherein said mixture comprises monostyrenated-p-cresol, distyrenated-p-cresol, and tristyrenated-p-cresol and exhibits an acid number of less than 0.1 mg KOH/gram.
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- Compositions and methods for inhibiting vinyl aromatic monomer polymerization
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Methods and compositions are provided for inhibiting the polymerization of vinyl aromatic monomers under distillation conditions. The compositions comprise a combination of a phenylenediamine compound and a hydroxylamine compound.
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- Preparation of N-substituted-N'-phenyl p-phenylenediamines
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The present invention relates to a process for the preparation of a N-substituted-N'-phenyl-p-phenylenediamine of the formula: STR1 comprising reacting (a) a mixture of (1) N-phenyl-p-quinoneimine of the formula: STR2 and (2) p-hydroxydiphenylamine in a mole ratio of N-phenyl-p-quinoneimine to p-hydroxydiphenylamine of from 1.5:1 to 1:1.5 with (b) a primary amine of the formula: in the presence of methanol wherein R1 is selected from the group of radicals consisting of alkyls having 1 to 20 carbon atoms, cycloalkyls having 6 to 8 carbon atoms and radicals of the structural formula: STR3 wherein R2 may be the same or different and is independently selected from the group of radicals consisting of hydrogen and an alkyl having 1 carbon atom, R3 is selected from the group of radicals consisting of an alkyl having 1 to 12 carbon atoms and n is an integer of from 0 to 6.
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- 2-Propanol derivatives as corrosion inhibitors
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New composition comprises a functional fluid in contact with ferrous metal and a corrosion inhibiting amount of at least one compound of formula (I) STR1 or a derivative thereof in which R1, R2 and R3 are, independently, hydrogen, a C1 -C15 straight or branched chain alkyl residue, a C5 -C12 cycloalkyl residue, a C6 -C15 aryl residue or C7 -C12 alkaryl residue, and R4 and R5 are, independently, hydrogen, 2-hydroxyethyl or 2-hydroxypropyl with the provisos that (a) R4 and R5 are not simultaneously hydrogen, (b) when R4 and R5 are each --CH2 --CH2 --OH, R1 and R2 are not simultaneously hydrogen and R3 is not a pentyl residue and (c) that polyalkylene and phenol or polycarboxylic ester co-additives are absent; as well as salts thereof. Some of the compounds of formula I are new.
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- Preparation of a N-substituted phenylenediamine
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The present invention relates to a process for the preparation of a N-substituted phenylenediamine of the formula: STR1 comprising reacting N-phenylquinoneimine of the formula: STR2 with a primary amine of the formula: wherein the molar ratio of II to III in the reaction mixture ranges from about 1:1 to 1:10; and wherein R is selected from the group of radicals consisting of alkyls having 1 to 20 carbon atoms, cycloalkyls having 6 to 8 carbon atoms and radicals of the structural formula: STR3 wherein R2 may be the same or different and is independently selected from the group of radicals consisting of hydrogen and an alkyl having 1 carbon atom, R3 is selected from the group of radicals consisting of an alkyl having 1 to 12 carbon atoms and n is an integer of from 0 to 6. The present process is characterized by its excellent yields of high purity N-substituted phenylenediamines.
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- Corrosion inhibiting composition
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A composition, in contact with a corrodable metal surface, which composition comprises: (a) an aqueous-based or oil-based system; and (b) as inhibitor for protecting the metal surface against corrosion, at least one compound having the formula I: STR1 as well as salts or partial esters thereof wherein: n is 0 or an integer ranging from 1 to 20, R is a straight or branched chain C4 -C30 alkyl group, optionally interrupted by one, two or three oxygen atoms or substituted by one, two or three hydroxy groups, a C5 -C12 cycloalkyl group, a C6 -C10 aryl group optionally substituted by one, two or three C1 -C12 alkyl groups, or a C7 -C13 aralkyl group which is optionally substituted by a hydroxyl group; R1 is H or a straight- or branched chain C1 -C4 alkyl group; R2 is H, a straight or branched chain C1 -C4 alkyl group or CO2 H; R3 is H, a straight or branched chain C1 -C4 alkyl group, --CH2 CO2 H or --CH2 CH2 CO2 H; R4 is H, a straight or branched chain C1 -C4 alkyl group or CO2 H; R5 is H, a straight or branched chain C1 -C4 alkyl group, CH2 CO2 H or CH2 CH2 CO2 H; provided that at least one group R4 must be CO2 H, with the provisio, that compositions comprising an oil-based system and a compound having the formula STR2 wherein R, R1 and R2 are hydrogen or alkyl radicals, having a total from 10 to 38 C-atoms, are excluded.
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- Heterogeneous Catalytic Transfer Hydrogenation of 4-Nitrodiphenylamine to p-Phenylenediamines
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p-Phenylenediamine analogues have been prepared from 4-nitrodophenylamine (1) by catalytic transfer hydrogenation in one stage; the process can be extended to the general condensation of a nitro compound with an alcohol (with Raney nickel as catalyst) or a ketone (with palladium as catalyst).
- Banerjee, Ankur A.,Mukesh, Doble
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p. 1275 - 1276
(2007/10/02)
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- Triazole-organodithiophosphate reaction product additives for functional fluids
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New reaction products, useful as additives for functional fluids, are obtained by reacting, at elevated temperature, (A) a triazole having the formula IA or IB: STR1 wherein R7 is hydrogen or a C1 -C20 alkyl residue; R8 and R9 are the same or different and each is C1 -C20 alkyl, C3 -C20 alkenyl, C5 -C12 cycloalkyl, C7 -C13 aralkyl, C6 -C10 aryl or R8 and R9, together with the nitrogen atom to which they are attached, form a 5-, 6- or 7-membered heterocyclic residue or R8 and R9 is each a residue of formula: wherein X is O, S or N(R12), R12 is hydrogen or C1 -C20 alkyl, "alkylene" is a C1 -C12 alkylene residue and n is 0 or an integer from 1 to 6; R10 is hydrogen, C1 -C20 alkyl or C6 -C10 aryl or C7 -C18 alkyl phenyl; and R11 is hydrogen, C1 -C20 alkyl or a residue --CH2 NR8 R9 wherein R8 and R9 have their previous significance; with (B) an organodithiophosphate having the formula: STR2 in which R13 is a C1 -C20 alkyl or C7 -C18 alkyl phenyl or C7 -C13 aralkyl group, M is a metal ion of Group IA, IB, IIA, IIB, VB, VIB, VIIB or VIII of the Periodic System of Elements, and y is the valency of M.
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- Stabilization of unsaturated carboxylic acid esters with mixtures of polyalkylene-amines and arylenediamines
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A method of inhibiting polymerization of unsaturated carboxylic acid esters and improved unsaturated carboxylic acid ester compositions are described. The method comprises, and the compositions are prepared by, incorporating into the ester composition a combination comprising polyalkyleneamine and arylenediamine of the formula STR1 in which X is hydrogen, chloro, trichloromethyl, trifluoromethyl, nitro, lower alkyl, lower alkoxy or phenoxy, R is hydrogen or alkyl, and R1 is alkyl or phenyl or R and R1 together with the nitrogen atom is a heterocycle selected from the group consisting of pyrrolidinyl, 2,5-dimethyl pyrrolidinyl, piperidino and hexahydro-1H-azepin-1-yl.
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