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Gongying Wang - One of the best experts on this subject based on the ideXlab platform.
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a facile route to prepare pbzr nanocomposite catalysts for the efficient synthesis of Diphenyl Carbonate
Catalysis Letters, 2021Co-Authors: Songlin Wang, Tong Chen, Hongying Niu, Nan Jiang, Lei Liang, Gongying WangAbstract:Diphenyl Carbonate is a versatile chemical intermediate and key building block for the synthesis of polyCarbonates. A facile route to prepare PbZr nanocomposites were developed using different precipitants to investigate the effect on the catalytic activity of the solid acid catalysts. The structure–performance relationship of the nanocomposites, dispersion of active components and structure stability, and the catalytic performance were thoroughly analyzed. The results showed that there existed the interaction between Zr and Pb, which induced the homogenous dispersion of Pb and high surface acid sites that could enhance the catalytic activities. Among the catalysts, PbZr–NH4OH represented the best catalytic performance and superior stability, indicating that NH4OH was more favorable compared with sodium hydroxide, ammonium Carbonate and urea. The research provides a valuable reference in a wide range application of nanocomposite preparation for the effective and clean production of various Carbonates.
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stir bar sorptive extraction and automatic two stage thermal desorption gas chromatography mass spectrometry for trace analysis of the byproducts from Diphenyl Carbonate synthesis
Microchemical Journal, 2020Co-Authors: Tao Liu, Tong Chen, Xiaoxue Yuan, Gang Zhang, Gongying WangAbstract:Abstract In this study, a fast and sensitive method based on stir bar sorptive extraction (SBSE) and two-step thermal desorption coupled with online gas chromatography-mass spectrometry was established to simultaneously analyse six trace byproducts [phenyl salicylate (PS), xanthone (XA), methyl o-hydroxybenzoate (MS), 2-methyl Diphenyl Carbonate (PTC), methyl o-methoxybenzoate (MSME) and phenyl o-methoxybenzoate (PSME)] generated in the process of Diphenyl Carbonate (DPC) synthesis. Analytes were enriched with multiple sorptive stir bars simultaneously, followed by thermal desorption, cryo-focusing, and instantaneous injection, effectively solving such problems as long adsorption time and small sample volumes compared with conventional stir bars. The main factors influencing SBSE and thermal desorption were studied. Optimized stir bar extraction conditions are as follows: the volume fraction of methanol is 10%, the extraction time is 6 min, and the stirring rate is 1200 rpm at room temperature (25 °C). Optimized two-step thermal desorption conditions are as follows: in the first desorption step, the desorption temperature is 300 °C, the desorption time is 10 min, and the valve and transmission line temperature is 200 °C; in the second desorption step, the cold trap temperature is −10 °C, which is increased at a rate of 100 °C/s to 320 °C and held for 5 min. A splitless mode and a split mode with a split ratio of 20:1 are used in the first and the second desorption step, respectively. Under the optimal conditions, the six byproducts generated in the synthesis of DPC via transesterification were quantitatively analyzed by external standard method. The results showed that, within the range of 1.0−100 ng/L for all of the six transesterification byproducts, this method revealed good linearity with correlation coefficients (r) ≥0.997. The limits of detection (LODs) were between 0.054 ng/L and 0.253 ng/L, the relative standard deviations (RSD) were from 5.2% to 11.5%, and the recoveries were 81.6%−102.6% (n = 3). The method is simple, rapid and has a wide linear range, high accuracy, and sensitivity, as well as good stability. It is suitable for simultaneous, rapid and selective analysis of six trace byproducts in the process of DPC synthesis. It can also provide vigorous data support and industrialization guidance for the selection of transesterification conditions and research on the formation mechanisms, distribution regularity, and even control of transesterification byproducts.
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influence of coordinating groups of organotin compounds on the fries rearrangement of Diphenyl Carbonate
RSC Advances, 2019Co-Authors: Tong Chen, Yi Zeng, Tao Liu, Xiaoxue Yuan, Gang Zhang, Gongying WangAbstract:In this paper, the Fries rearrangement of Diphenyl Carbonate (DPC) catalyzed by organotin compounds with different coordination groups was studied for the first time. The electronic effect and steric hindrance of the coordinating groups were discussed with respect to the reactivity of DPC rearrangement. The results showed that both the electronic effect and steric hindrance of the coordinating groups influenced the acidity of the active tin centers and then affected the catalytic performance of organotin as a Lewis acid for the rearrangement of DPC, and the influence of the electronic effect is greater than that of steric hindrance. The catalytic activity is in the order of BuSnO(OH) > Bu2SnO > Bu2Sn(OCOC11H23)2 > BuSnCl3 > Bu3SnOSnBu3 > Bu3SnCl, and Bu2SnO showed the best catalytic activity due to its strong electron absorption effect, small steric hindrance, and good stability. Under the optimum reaction conditions, the conversion of DPC was up to 93%, and the yields of phenyl salicylate (PS) and xanthone (XA) were 62% and 28%, respectively. In addition, a reaction mechanism of DPC rearrangement catalyzed by the organotin compounds was speculated. This research can provide vigorous theoretical data support to control the byproducts produced by DPC rearrangement in the process of DPC synthesis. It also provides a new route for the preparation of PS and XA.
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highly effective transformation of methyl phenyl Carbonate to Diphenyl Carbonate with recyclable pb nanocatalyst
RSC Advances, 2019Co-Authors: Songlin Wang, Gongying Wang, Tong Chen, Hongying Niu, Jianji Wang, Jiamin ZhangAbstract:Diphenyl Carbonate (DPC) is a type of versatile industrial chemical, and the disproportionation of methyl phenyl Carbonate (MPC) is a key step to produce DPC. However, the design and formulation of a catalyst for the efficient synthesis of DPC is a major challenge due to its small equilibrium constant. The support material is a critical factor influencing the performance of Pb nanocatalysts. Thus, a series of Pb-based catalysts over MgO, ZrO2, SiO2, TiO2 and Al2O3 were prepared to investigate the effect of the support materials on the physicochemical properties and catalytic performances for the conversion of MPC to effectively synthesize DPC. The catalysts were well characterized by XRD, BET, TEM, XPS, ICP-OES, H2-TPR, Py-IR and NH3-TPD. The results showed that the nature of the support obviously affected the structural properties and catalytic performances, and Pb was dispersed better on SiO2, TiO2, ZrO2 and MgO than on Al2O3, and showed stronger metal-support interaction over MgO and ZrO2. The activity results revealed that PbO/MgO and PbO/ZrO2 exhibited higher catalytic activities because they contained higher Pb dispersion and more Lewis acid sites, and the catalytic activities followed the order PbO/MgO > PbO/ZrO2 > PbO/SiO2 > PbO/Al2O3 > PbO/TiO2. On the contrary, PbO/MgO and PbO/ZrO2 exhibited better reusability due to strong interaction between the highly dispersed Pb and the supports, and the activity decrease in the case of PbO/SiO2, PbO/Al2O3 and PbO/TiO2 mainly resulted from the Pb leaching loss. This work would contribute to exploiting novel catalytic materials in a wide range of applications for the efficient synthesis of organic Carbonates.
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effect of zirconia polymorph on the synthesis of Diphenyl Carbonate over supported lead catalysts
Molecular Catalysis, 2019Co-Authors: Songlin Wang, Tong Chen, Hongying Niu, Jianji Wang, Mengjun Guo, Gongying WangAbstract:Abstract Zirconia supported Pb-based catalysts with purely tetragonal/monoclinic crystals were prepared and analyzed well by XRD, TEM-EDS, XPS, H2-TPR, BET, Py-IR and NH3-TPD techniques. The results indicate that zirconia polymorph has great effect on their structure and catalytic property for the synthesis of Diphenyl Carbonate (DPC) through methyl phenyl Carbonate (MPC) disproportionation due to the differences of surface chemical properties, and tetragonal zirconia supported lead catalyst (TZ-Pb) shows bigger dispersion degree of PbO, higher surface area and Lewis acid amounts and thereby exhibits higher catalytic activity and selectivity compared to monoclinic zirconia supported catalyst (MZ-Pb). Furthermore, TZ-Pb shows better reusability due to strong metal-support interaction and may be readily recycled for at least four times without remarkable reactivity loss. This work provides a prospective reference for the facile and efficient synthesis of zirconia polymorph materials in various catalysis applications.
Tong Chen - One of the best experts on this subject based on the ideXlab platform.
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a facile route to prepare pbzr nanocomposite catalysts for the efficient synthesis of Diphenyl Carbonate
Catalysis Letters, 2021Co-Authors: Songlin Wang, Tong Chen, Hongying Niu, Nan Jiang, Lei Liang, Gongying WangAbstract:Diphenyl Carbonate is a versatile chemical intermediate and key building block for the synthesis of polyCarbonates. A facile route to prepare PbZr nanocomposites were developed using different precipitants to investigate the effect on the catalytic activity of the solid acid catalysts. The structure–performance relationship of the nanocomposites, dispersion of active components and structure stability, and the catalytic performance were thoroughly analyzed. The results showed that there existed the interaction between Zr and Pb, which induced the homogenous dispersion of Pb and high surface acid sites that could enhance the catalytic activities. Among the catalysts, PbZr–NH4OH represented the best catalytic performance and superior stability, indicating that NH4OH was more favorable compared with sodium hydroxide, ammonium Carbonate and urea. The research provides a valuable reference in a wide range application of nanocomposite preparation for the effective and clean production of various Carbonates.
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stir bar sorptive extraction and automatic two stage thermal desorption gas chromatography mass spectrometry for trace analysis of the byproducts from Diphenyl Carbonate synthesis
Microchemical Journal, 2020Co-Authors: Tao Liu, Tong Chen, Xiaoxue Yuan, Gang Zhang, Gongying WangAbstract:Abstract In this study, a fast and sensitive method based on stir bar sorptive extraction (SBSE) and two-step thermal desorption coupled with online gas chromatography-mass spectrometry was established to simultaneously analyse six trace byproducts [phenyl salicylate (PS), xanthone (XA), methyl o-hydroxybenzoate (MS), 2-methyl Diphenyl Carbonate (PTC), methyl o-methoxybenzoate (MSME) and phenyl o-methoxybenzoate (PSME)] generated in the process of Diphenyl Carbonate (DPC) synthesis. Analytes were enriched with multiple sorptive stir bars simultaneously, followed by thermal desorption, cryo-focusing, and instantaneous injection, effectively solving such problems as long adsorption time and small sample volumes compared with conventional stir bars. The main factors influencing SBSE and thermal desorption were studied. Optimized stir bar extraction conditions are as follows: the volume fraction of methanol is 10%, the extraction time is 6 min, and the stirring rate is 1200 rpm at room temperature (25 °C). Optimized two-step thermal desorption conditions are as follows: in the first desorption step, the desorption temperature is 300 °C, the desorption time is 10 min, and the valve and transmission line temperature is 200 °C; in the second desorption step, the cold trap temperature is −10 °C, which is increased at a rate of 100 °C/s to 320 °C and held for 5 min. A splitless mode and a split mode with a split ratio of 20:1 are used in the first and the second desorption step, respectively. Under the optimal conditions, the six byproducts generated in the synthesis of DPC via transesterification were quantitatively analyzed by external standard method. The results showed that, within the range of 1.0−100 ng/L for all of the six transesterification byproducts, this method revealed good linearity with correlation coefficients (r) ≥0.997. The limits of detection (LODs) were between 0.054 ng/L and 0.253 ng/L, the relative standard deviations (RSD) were from 5.2% to 11.5%, and the recoveries were 81.6%−102.6% (n = 3). The method is simple, rapid and has a wide linear range, high accuracy, and sensitivity, as well as good stability. It is suitable for simultaneous, rapid and selective analysis of six trace byproducts in the process of DPC synthesis. It can also provide vigorous data support and industrialization guidance for the selection of transesterification conditions and research on the formation mechanisms, distribution regularity, and even control of transesterification byproducts.
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influence of coordinating groups of organotin compounds on the fries rearrangement of Diphenyl Carbonate
RSC Advances, 2019Co-Authors: Tong Chen, Yi Zeng, Tao Liu, Xiaoxue Yuan, Gang Zhang, Gongying WangAbstract:In this paper, the Fries rearrangement of Diphenyl Carbonate (DPC) catalyzed by organotin compounds with different coordination groups was studied for the first time. The electronic effect and steric hindrance of the coordinating groups were discussed with respect to the reactivity of DPC rearrangement. The results showed that both the electronic effect and steric hindrance of the coordinating groups influenced the acidity of the active tin centers and then affected the catalytic performance of organotin as a Lewis acid for the rearrangement of DPC, and the influence of the electronic effect is greater than that of steric hindrance. The catalytic activity is in the order of BuSnO(OH) > Bu2SnO > Bu2Sn(OCOC11H23)2 > BuSnCl3 > Bu3SnOSnBu3 > Bu3SnCl, and Bu2SnO showed the best catalytic activity due to its strong electron absorption effect, small steric hindrance, and good stability. Under the optimum reaction conditions, the conversion of DPC was up to 93%, and the yields of phenyl salicylate (PS) and xanthone (XA) were 62% and 28%, respectively. In addition, a reaction mechanism of DPC rearrangement catalyzed by the organotin compounds was speculated. This research can provide vigorous theoretical data support to control the byproducts produced by DPC rearrangement in the process of DPC synthesis. It also provides a new route for the preparation of PS and XA.
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highly effective transformation of methyl phenyl Carbonate to Diphenyl Carbonate with recyclable pb nanocatalyst
RSC Advances, 2019Co-Authors: Songlin Wang, Gongying Wang, Tong Chen, Hongying Niu, Jianji Wang, Jiamin ZhangAbstract:Diphenyl Carbonate (DPC) is a type of versatile industrial chemical, and the disproportionation of methyl phenyl Carbonate (MPC) is a key step to produce DPC. However, the design and formulation of a catalyst for the efficient synthesis of DPC is a major challenge due to its small equilibrium constant. The support material is a critical factor influencing the performance of Pb nanocatalysts. Thus, a series of Pb-based catalysts over MgO, ZrO2, SiO2, TiO2 and Al2O3 were prepared to investigate the effect of the support materials on the physicochemical properties and catalytic performances for the conversion of MPC to effectively synthesize DPC. The catalysts were well characterized by XRD, BET, TEM, XPS, ICP-OES, H2-TPR, Py-IR and NH3-TPD. The results showed that the nature of the support obviously affected the structural properties and catalytic performances, and Pb was dispersed better on SiO2, TiO2, ZrO2 and MgO than on Al2O3, and showed stronger metal-support interaction over MgO and ZrO2. The activity results revealed that PbO/MgO and PbO/ZrO2 exhibited higher catalytic activities because they contained higher Pb dispersion and more Lewis acid sites, and the catalytic activities followed the order PbO/MgO > PbO/ZrO2 > PbO/SiO2 > PbO/Al2O3 > PbO/TiO2. On the contrary, PbO/MgO and PbO/ZrO2 exhibited better reusability due to strong interaction between the highly dispersed Pb and the supports, and the activity decrease in the case of PbO/SiO2, PbO/Al2O3 and PbO/TiO2 mainly resulted from the Pb leaching loss. This work would contribute to exploiting novel catalytic materials in a wide range of applications for the efficient synthesis of organic Carbonates.
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effect of zirconia polymorph on the synthesis of Diphenyl Carbonate over supported lead catalysts
Molecular Catalysis, 2019Co-Authors: Songlin Wang, Tong Chen, Hongying Niu, Jianji Wang, Mengjun Guo, Gongying WangAbstract:Abstract Zirconia supported Pb-based catalysts with purely tetragonal/monoclinic crystals were prepared and analyzed well by XRD, TEM-EDS, XPS, H2-TPR, BET, Py-IR and NH3-TPD techniques. The results indicate that zirconia polymorph has great effect on their structure and catalytic property for the synthesis of Diphenyl Carbonate (DPC) through methyl phenyl Carbonate (MPC) disproportionation due to the differences of surface chemical properties, and tetragonal zirconia supported lead catalyst (TZ-Pb) shows bigger dispersion degree of PbO, higher surface area and Lewis acid amounts and thereby exhibits higher catalytic activity and selectivity compared to monoclinic zirconia supported catalyst (MZ-Pb). Furthermore, TZ-Pb shows better reusability due to strong metal-support interaction and may be readily recycled for at least four times without remarkable reactivity loss. This work provides a prospective reference for the facile and efficient synthesis of zirconia polymorph materials in various catalysis applications.
Jae Sung Lee - One of the best experts on this subject based on the ideXlab platform.
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Oxidative carbonylation of phenol to Diphenyl Carbonate over supported palladium catalysts
Journal of Molecular Catalysis A-chemical, 2000Co-Authors: Ho Young Song, Eun Duck Park, Jae Sung LeeAbstract:Abstract Oxidative carbonylation of phenol to form Diphenyl Carbonate (DPC) was investigated in the multi-step electron transfer system containing homogeneous or heterogeneous palladium as the main component. Carbon-supported Pd catalyst showed a better DPC yield than the best homogeneous system with Pd(OAc)2 for the same amount of palladium. For the supported palladium catalyst, the hydrophobicity of the supports appeared to be critical for high yields of DPC. The palladium remained in the metallic state and dissolution into the reaction solution was, if there was any, negligible. Effects of promoters in carbon-supported Pd catalyst system were also examined.
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Oxidative carbonylation of phenol to Diphenyl Carbonate over supported palladium catalysts
Journal of Molecular Catalysis A: Chemical, 2000Co-Authors: Ho Young Song, Eun Duck Park, Jae Sung LeeAbstract:Oxidative carbonylation of phenol to form Diphenyl Carbonate (DPC) was investigated in the multi-step electron transfer system containing homogeneous or heterogeneous palladium as the main component. Carbon-supported Pd catalyst showed a better DPC yield than the best homogeneous system with Pd(OAc)(2) for the same amount of palladium. For the supported palladium catalyst, the hydrophobicity of the supports appeared to be critical for high yields of DPC. The palladium remained in the metallic state and dissolution into the reaction solution was, if there was any, negligible. Effects of promoters in carbon-supported Pd catalyst system were also examined. (C) 2000 Elsevier Science B.V. All rights reservedclose555
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A new process for the synthesis of Diphenyl Carbonate from dimethyl Carbonate and phenol over heterogeneous catalysts
Catalysis Letters, 1999Co-Authors: Won Bae Kim, Jae Sung LeeAbstract:The two-step synthesis of Diphenyl Carbonate (DPC) from dimethyl Carbonate (DMC) and phenol has been compared in liquid phase and gas phase, both over heterogeneous catalysts. In the first step, equilibrium yields of methyl phenyl Carbonate (MPC) in the transesterification of DMC and phenol were very low at low temperatures in the liquid phase although reaction rates were fast. This endothermic reaction was more favorable at high temperatures in the gas-phase reaction. Titanium oxide catalysts supported on SiO_2 or activated carbon were found to be effective in a continuous gas flow reactor. In case of the second step, the disproportionation of MPC, selective formation of DPC was not feasible in the gas-phase reaction due to extensive side reactions. However, there was no by-product in the liquid-phase reaction over the TiO_2/SiO_2 catalyst. Therefore, our proposed two-step synthesis process consists of the gas-phase transesterification of DMC and phenol followed by the liquid-phase disproportionation of MPC to DPC, both over the TiO_2/SiO_2 catalyst.
Toshihide Horikawa - One of the best experts on this subject based on the ideXlab platform.
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design and control of Diphenyl Carbonate reactive distillation process with thermally coupled and heat integrated stages configuration
Computers & Chemical Engineering, 2019Co-Authors: Hao-yeh Lee, Rafael J Alcantaraavila, Masataka Terasaki, Junlin Chen, Kenichiro Sotowa, Chienying Chen, Toshihide HorikawaAbstract:Abstract It has been extensively proven that thermally coupled distillation columns can effectively use less energy than their conventional counterparts. Similarly, the extension to reactive systems has also shown that thermally coupled reactive distillation columns can reduce the energy consumption in comparison with their conventional reactive distillation counterparts. This work aims to show that by realizing heat integration between thermally coupled columns at different pressure, further energy savings can be attained. The Diphenyl Carbonate production process has been taken up to show that there is a synergistic effect when thermally coupling and heat integration are combined in the same distillation sequence. The results showed that the proposed system could attain 47% energy savings in comparison with conventional a reactive distillation sequence while keeping good rejection of throughput and feed composition disturbances.
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design and control of reactive distillation sequences with heat integrated stages to produce Diphenyl Carbonate
Industrial & Engineering Chemistry Research, 2017Co-Authors: Rafael J Alcantaraavila, Hao-yeh Lee, Masataka Terasaki, Junlin Chen, Kenichiro Sotowa, Toshihide HorikawaAbstract:Reactive distillation (RD) in quaternary systems has gained importance when one of the reagents is in excess. In this work, higher energy savings in a reactive distillation sequence is addressed to produce Diphenyl Carbonate, which is a crucial precursor of polyCarbonate. Energy savings were attained through heat integration between the high-pressure RD column and the low-pressure separation column. The design of sequences with heat-integrated stages was done by combining simulation and optimization. The sequence with one heat-integrated stage realized the minimum energy consumption with energy savings around 22% and cost savings around 12% in comparison with the conventional reactive distillation sequence. Also, two control schemes for the best design configuration have also been studied in this work. The results showed that the control scheme that manipulates the reboiler duty and reflux ratio to control two stage temperatures can provide excellent responses under throughput and feed composition disturb...
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Design and Control of Reactive Distillation Sequences with Heat-Integrated Stages To Produce Diphenyl Carbonate
2016Co-Authors: Rafael J. Alcántara-avila, Hao-yeh Lee, Masataka Terasaki, Junlin Chen, Kenichiro Sotowa, Toshihide HorikawaAbstract:Reactive distillation (RD) in quaternary systems has gained importance when one of the reagents is in excess. In this work, higher energy savings in a reactive distillation sequence is addressed to produce Diphenyl Carbonate, which is a crucial precursor of polyCarbonate. Energy savings were attained through heat integration between the high-pressure RD column and the low-pressure separation column. The design of sequences with heat-integrated stages was done by combining simulation and optimization. The sequence with one heat-integrated stage realized the minimum energy consumption with energy savings around 22% and cost savings around 12% in comparison with the conventional reactive distillation sequence. Also, two control schemes for the best design configuration have also been studied in this work. The results showed that the control scheme that manipulates the reboiler duty and reflux ratio to control two stage temperatures can provide excellent responses under throughput and feed composition disturbances. Furthermore, the feed ratio of the RD column is not the manipulating variable like in the conventional RD process. However, an internally stoichiometric balance result can be observed under composition disturbance
Guozhi Fan - One of the best experts on this subject based on the ideXlab platform.
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znbr2 supported on silica coated magnetic nanoparticles of fe3o4 for conversion of co2 to Diphenyl Carbonate
RSC Advances, 2015Co-Authors: Guozhi Fan, Tao Fang, Shanshan Luo, Guangsen SongAbstract:A magnetic Fe3O4@SiO2–ZnBr2 catalyst was prepared by supporting ZnBr2 on silica-coated magnetic nanoparticles of Fe3O4 and used as a recoverable catalyst for the direct synthesis of Diphenyl Carbonate (DPC) from CO2 and phenol in the presence of carbon tetrachloride. The as-prepared catalyst was characterized by infrared spectroscopy (IR), powder X-ray diffraction (XRD), a X-ray photoelectron spectrometer (XPS) and BET. Zn loading in the supported catalyst and leaching during the reaction process were determined by atomic absorption spectroscopy (AAS). It was found that Fe3O4@SiO2–ZnBr2 showed higher catalytic activity than homogenous ZnCl2 and ZnI2 as well as homogenous ZnBr2. With this new catalyst under optimized conditions, a yield of DPC at 28.1% was obtained. The heterogeneous catalyst Fe3O4@SiO2–ZnBr2 can also be recovered by a permanent magnet after the reaction and reused up to 4 times without noticeable deactivation.
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synthesis of Diphenyl Carbonate from compressed carbon dioxide and phenol without use of organic solvent
Fuel Processing Technology, 2011Co-Authors: Guozhi Fan, Zhigang Wang, Bing Zou, Min WangAbstract:Diphenyl Carbonate (DPC) was synthesized from CO2 and phenol catalyzed by Lewis acids. Compressed CO2 was used as reactant and solvent. It was found that the conversion of phenol and the yield of DPC are dependent on the metal center of Lewis acids, and zinc halides have better catalytic performance than aluminum halides. The reaction of CO2 with phenol is sensitive to pressure, temperature, and reaction time, and it is improved using triethylamine as acid acceptor. A 31.7% DPC yield was obtained under optimized reaction conditions: 9 MPa at 100 °C for 3 h.
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A novel method to synthesize Diphenyl Carbonate from carbon dioxide and phenol in the presence of methanol
Catalysis Science & Technology, 2011Co-Authors: Guozhi Fan, Haitao Zhao, Zhenxiao Duan, Tao Fang, Minghai WanAbstract:A novel method for the direct synthesis of Diphenyl Carbonate (DPC) from carbon dioxide and phenol catalyzed by Lewis acid in the presence of methanol was developed. It was found that the simple Lewis acids are not effective for catalyzing the production of DPC, but (salen)Co(OAc) containing a quaternary phosphonium salt unit anchored on the ligand displayed excellent catalytic activity under mild conditions using dense carbon dioxide as reactant and solvent. A possible mechanism for the formation of DPC was proposed based on the GC-MS analysis and DFT calculation.
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synthesis of Diphenyl Carbonate from phenol and carbon dioxide in the presence of carbon tetrachloride and zinc chloride
Catalysis Letters, 2009Co-Authors: Guozhi Fan, Bing Zou, Shinichiro Fujita, Masahiro Nishiura, Xiangchun Meng, Masahiko AraiAbstract:Diphenyl Carbonate (DPC) was synthesized from phenol and dense phase CO2 in the presence of CCl4 and K2CO3 using different catalysts of ZnCl2, ZnBr2, Lewis acid ionic liquids including 1-butyl-3-methylimidazolium chloride (BMIMCl) and bromide (BMIMBr). It was found that K2CO3 was not required, ZnCl2 and ZnBr2 were similar in the catalytic performance, and the use of BMIMCl and BMIMBr was not effective for the production of DPC. For the reactions with ZnCl2 in CCl4, the effects of such reaction variables as temperature, CO2 pressure, the amount of ZnCl2, and the volume of CCl4 were studied in detail. It was shown that the pressure was less influential while a larger amount of ZnCl2, a smaller volume of CCl4, and a low temperature of around 100°C were beneficial for the synthesis of DPC. On the basis of the results obtained, possible reaction mechanisms were discussed.
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oxidative carbonylation of phenol to Diphenyl Carbonate catalyzed by palladium complexes bridged with n n ligands over functionalized silica
Applied Organometallic Chemistry, 2006Co-Authors: Guozhi FanAbstract:Heterogeneous palladium catalysts anchored on functionalized silica were prepared by sol–gel methods and their catalytic properties for the oxidative carbonylation of phenol to Diphenyl Carbonate (DPC) were investigated. The catalysts were characterized by means of IR, XPS, EA and BET. The Pd loading in the heterogeneous catalysts and leaching in solution were detected by atomic absorption. The effects of different reaction parameters such as temperature, solvent and inorganic cocatalyst on the yield of DPC and Pd leaching were also studied. It was found that Cu2O and tetrahydrofuran (THF) were the best partners with these heterogeneous catalysts. In the presence of 3 A molecular sieves as dehydrating agent, the heterogeneous palladium catalyst prepared from 2-acylpyridine revealed excellent catalytic performance and stability at 110 °C for 5 h, giving 13.7% yield of DPC based on phenol and 4.0% Pd loss in solution. The heterogeneous catalyst was more active and stable compared with traditional supported PdC catalyst under the same reaction conditions. Copyright © 2005 John Wiley & Sons, Ltd.