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Papers by Sutasinee Neramittagapong

Applied Environmental Research, Mar 29, 2023

Environmental Science and Pollution Research

Materials Today: Proceedings

Energy Reports, 2020

Abstract This work was to optimize operating parameters for phenol production via partial oxidati... more Abstract This work was to optimize operating parameters for phenol production via partial oxidation. The essential settings, NaOH loading of 4–20 g/L, reaction temperatures of 140–180 °C, and time of 15–45 min, were set as the independent parameters for designing the experiments. A set of tests was generated using Box–Behnken Design (BBD) and performed in a high-pressure reactor at the constant air pressure of 2 bars. A produced phenol concentration was assigned as a response target for evaluating an optimal condition. From the results, a quadratic model of actual data was fit with high accuracy (R2 of 94.1%). A response surface methodology (RSM) was used to evaluate the operating parameters effect on the phenol formation. It showed that the temperature rising affected phenol formation due to the creation of aldehydes at low temperatures and phenol re-polymerization. The presence of NaOH plays an essential role in the production of phenol. It may increase the hydroxyl group’s rate to an aromatic ring that yields a high percentage of phenol production. For the reaction time, the longer time gave a higher yield of phenol. However, it slightly increased after 30 min. The predicted optimal condition was determined at the temperature of 161 °C, the NaOH loading of 16.4 mg/L, and the reaction time of 36.2 min. Three experiments were performed at the optimal point to verify the prediction. It was found that the phenol concentration of 30 ± 1 mg/L was yielded at this condition. Moreover, the reaction temperature and the initial pressure of air were not severe. It indicates that the partial oxidation of aqueous lignin solution can produce phenol at mild conditions.

Journal of the Japan Institute of Energy

This study aimed to investigate the effects of the reaction time and temperature on the hydrolysi... more This study aimed to investigate the effects of the reaction time and temperature on the hydrolysis of sucrose to glucose and fructose using an Amberlyst-15 catalyst. The experiments were conducted in a 100 mL highpressure batch reactor. The initial sucrose concentration of 500 g/L, initial nitrogen pressure of 101.3 kPa, and catalyst loading of 0.2 g remained constant during the reactions. An increase in the reaction temperature and time, which varied in the range of 303-373 K and 1-12 h, respectively, resulted in an increase in the glucose and fructose yields owing to the high acidity of Amberlyst-15. The most elevated glucose and fructose yields based on carbon moles of 0.50 mol-C/mol-C and 0.49 mol-C/mol-C, respectively, were obtained at 373 K after 3 h with complete sucrose conversion. Moreover, Amberlyst-15 was reused for more than 24 cycles, with complete sucrose conversion and a high yield of inverted sugar. Therefore, Amberlyst-15 is an active, selective, and stable catalyst for sucrose hydrolysis.

Brazilian Journal of Chemical Engineering, 2009

RH-MCM-41 was synthesized by using silica from rice husk and further modified to increase acidity... more RH-MCM-41 was synthesized by using silica from rice husk and further modified to increase acidity by adding Al with grafting method with Si/Al ratio of 75 and 25. The resulting materials were referred to as RH-AlMCM-41(75) and RH-AlMCM-41(25). The XRD spectra of all RH-AlMCM-41 confirmed a mesoporous structure of MCM-41. Surface areas of all RH-AlMCM-41 were in the range of 700-800 m 2 /g, lower than that of the parent RH-MCM-41, which was 1230 m 2 /g. After Al addition the Si/Al ratios of RH-AlMCM-41(75) and RH-AlMCM-41(25) were higher than that of the parent RH-MCM-41. The RH-AlMCM-41 materials were used as supports for bimetallic platinum−iron catalysts, denoted as Pt-Fe/RH-AlMCM-41, with Pt and Fe amounts of 0.5 and 5.0% by weight, respectively. Results from TPR indicated that the presence of Al might assist the interaction between Pt and Fe as the reduction temperature of iron oxides shifted to a lower value. All catalysts were active for phenol hydroxylation using H 2 O 2 as an oxidant, for which the highest conversions were observed on the RH-MCM-41 material with the highest surface area. The acidity of the supports did not present a significant role in improving the catalytic performance.

Nihon Enerugī Gakkaishi, Mar 20, 2022

The photocatalytic reduction of carbon dioxide into methanol over modified SiO2-Al2O3 supported T... more The photocatalytic reduction of carbon dioxide into methanol over modified SiO2-Al2O3 supported TiO2 catalyst at atmospheric pressure was investigated. The SiO2-Al2O3 supported TiO2 catalyst was modified by coating the bimetallic metal (Ni-Cu) using the sol-gel method with various Ni-Cu loading in the range of 0wt.% to 5wt.%. All prepared catalysts were characterized using Scanning electron microscopy (SEM), X-ray powder diffraction (XRD), N2 adsorption-desorption, UV-vis diffuse reflectance spectrometer (UV-Vis-DRS), and Photoluminescence Spectroscopy (PL). The reaction was performed in a liquid-phase batch-reactor equipped with a UVC lamp (125W) as a source of UV radiation. The reactions were tested at atmospheric pressure and the temperature of 25 °C for 5 h with a catalyst loading of 4 g/L. It was found that the coating of bimetallic metal had effects on the reduction of surface area and energy bandgap. The prepared catalyst had a surface area in the range 108 m 2 /g to 199.6 m 2 /g, and the bandgap energy varied from 3.01 eV to 3.08 eV. The presence of Ni (3wt.%) and Cu (2wt.%) on the TiO2/ SiO2-Al2O3 catalyst had slower recombination rate of electron-hole pairs than that of TiO2/SiO2-Al2O3 catalyst. The highest methanol production rate of 405.08 µmol/g cat was obtained after 2 h over 3wt.%Ni-2wt.%Cu-TiO2/SiO2-Al2O3. This production rate was three times higher than that over unmodified TiO2/SiO2-Al2O3 due to good retardation of electron-hole pair recombination.

Journal of the Japan Institute of Energy, 2020

This work aimed to optimize lignin conversion to vanillin by hydrothermal method. An experiment w... more This work aimed to optimize lignin conversion to vanillin by hydrothermal method. An experiment was designed by Box-Benhken Design (BBD). Temperature, NaOH concentration, and reaction time were chosen as independent parameters for achieving the optimum reaction condition. The reaction products were analyzed by highperformance liquid chromatography. Based on the experimental results, the optimum condition for the hydrothermal process was predicted using the response surface method. The maximum vanillin production of 18.1 mg/L was predicted at the optimum condition given by the temperature of 142 °C, NaOH concentration of 9.2 g/L, and reaction time of 32 min. The conversion of lignin to vanillin was experimented using the predicted optimal condition to verify the prediction. It was found that the hydrothermal method at the optimum condition yielded 18.1 ± 2 mg/L of vanillin, which was in good agreement with the predicted value. It was also found that the yield of vanillin was influenced by temperature, NaOH concentration, and the interaction of both parameters, whereas the reaction time was much less influential.

Advanced Materials Research, 2014

Aniline was removed by photocatalysis reaction using zinc oxide (ZnO, ZnO/Al2O3 and ZnO/SiO2) as ... more Aniline was removed by photocatalysis reaction using zinc oxide (ZnO, ZnO/Al2O3 and ZnO/SiO2) as catalysts. The oxidation reactions were carried out in a batch reactor. The experiment was designed by Pleckett-Burman Full Factorial Design (FFD) for screening test. The FFD was used to factors screening of 3 factors: wt% of ZnO, catalyst loading and UV light source on aniline removal. The equation model for factors screening was well fitted to the experiment data, which was observed by R2 coefficient of 0.95. The results show that wt% of ZnO and catalysts loading were the significant effects. The highest percentage aniline removal of 82.7% was achieved at the reaction condition; 0.5g of ZnO catalyst and 30wt%ZnO under UV-C irradiation. Moreover, it was found that Pleckett-Burman FFD was useful in factor screening of the aniline removal by photochemical reaction over ZnO-based catalysts.

Advanced Materials Research, 2014

The goal of this research was to synthesize two different catalysts, namely K-OMS-2 and MnOx. The... more The goal of this research was to synthesize two different catalysts, namely K-OMS-2 and MnOx. The K-OMS-2 was an octahedral manganese complex prepared by hydrothermal method, while manganese oxide (MnOx) was directly synthesized by precipitation method. Both catalysts were employed to decompose toluene, an organic solvent that is widely used in industries. The catalysts were characterized by means of X-ray diffraction (XRD) and N2-physorption. The surface areas of K-OMS-2 and MnOx were 83.50 and 20.04 m2/g, respectively. The precipitation route gave XRD patterns of γ-Mn2O3 structure, and a successful structure of an octahedral molecular sieve manganese oxide was obtained by the hydrothermal method. The toluene degradation was carried out in gas hourly space velocity (GHSV) range of 20,000-60,000 h-1 with toluene concentration of 7,700 ppmv. The higher GHSV over K-OMS-2 gave the lower contact time consequently resulting in the lower %toluene degradation, whereas the best GHSV over γ-...

Key Engineering Materials, 2013

Adsorption of Zn(II) and Pb(II) from aqueous solution were studied by using modified coir pith as... more Adsorption of Zn(II) and Pb(II) from aqueous solution were studied by using modified coir pith as an adsorbent. The extended adsorption conditions were investigated as a function of calcination temperature, contact time, adsorbent size, initial pH of solution and initial Zn(II) and Pb(II) concentrations. The adsorption capacity increased rapidly in first 5 minute and reached equilibrium in 120 minutes for Zn(II) and 10 minutes for Pb(II). In case of Zn(II); the results showed that the calcination temperature of modified coir pith above 600oC gave the higher adsorption capacity. The sizes of modified coir pith have no effect on the adsorption capacity. The adsorption capacity increased with increasing initial solution pH value. In case of Pb(II); the calcination temperature of modified coir pith showed no effect on the adsorption capacity. The sizes of modified coir pith showed a little effect on the adsorption capacity. The adsorption capacity increased with increasing of initial so...

Journal of Renewable Materials

Isosorbide is a multipurpose chemical that can be produced from renewable resources. Specifically... more Isosorbide is a multipurpose chemical that can be produced from renewable resources. Specifically, it has been investigated as a replacement for toxic bisphenol A (BPA) in the production of polycarbonate (PC). In this study, the synthesis of isosorbide by sorbitol dehydration using a cerium-based catalyst derived from calcined cerium (IV) sulfate (300°C, 400°C, 450°C, 500°C, and 650°C) was investigated. The reaction occurred in a high-pressure reactor containing nitrogen gas. Advanced instrumental techniques were applied to analyze the characteristics of the calcined catalyst. The results showed that the calcined catalysts demonstrated different crystalline structures and sulfate species at different temperatures. However, the acidic properties (strength and amount) of the catalyst did not change with the calcination temperature. The cerium (IV) sulfate calcined at 400°C exhibited the best catalytic performance, achieving the highest isosorbide yield (55.7%) and complete conversion of sorbitol at 180°C, 20 bar of N 2 , and 6 h using CeSO-400. The presence of a sulfate group on the catalyst was the most important factor in determining the catalytic performance of sorbitol dehydration to isosorbide. This work suggests that CeSO-400 catalysts may play an important role in reducing reaction conditions.

Nihon Enerugī Gakkaishi, Mar 20, 2022

This research aimed to study the photocatalytic reduction of CO2 into methanol over TiO2 supporte... more This research aimed to study the photocatalytic reduction of CO2 into methanol over TiO2 supported on SiO2-Al2O3 catalysts. The effects of reaction time and the influence of copper (1-4 %wt) doped on SiO2-Al2O3 on the methanol yield were investigated. The experiments were carried out in a 50 ml batch reactor under UV irradiation. The catalysts prepared by the sol-gel method were characterized by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The result indicated that the maximum of methanol production was obtained after the irradiation of 2 h and slightly reduced after that, probably due to the methanol oxidation process. The highest methanol production of 1258.8 µmol gcat-1 was obtained when 2%wt Cu-TiO2/SiO2-Al2O3 catalyst. This was 5.98 times that obtained from the undoped photocatalyst. The presence of the CuO phase could separate the electron from the TiO2 conduction band to move into the CuO conduction band. However, the high content of CuO could increase the TiO2 crystal size. Moreover, the catalysts could be reused seven times for the purpose. Therefore, the result of this research indicated the potential of using Cu with TiO2/SiO2-Al2O3 catalyst for reducing CO2 emission to the environment.

Journal of the Japan Institute of Energy

Energy Reports, 2020

Photocatalytic reduction of carbon dioxide into methanol fuel over the Ni-doped TiO2 catalyst has... more Photocatalytic reduction of carbon dioxide into methanol fuel over the Ni-doped TiO2 catalyst has been investigated. The experiments were carried out in a 50 ml batch reactor under UV irradiation. Ni/TiO2 photocatalysts were prepared by an impregnation method. The properties of the catalyst were characterized by X-ray photoelectron spectroscopy (XPS), UV–Vis diffuse reflectance (UV–DR). Moreover, the effect of reaction time and Ni loading on the methanol conversion were investigated. The result indicated that the maximum of methanol production was obtained after the irradiation of 3 h and slightly reduced due to the methanol oxidation process. The Ni loading catalyst showed the higher methanol concentration than that over undoped TiO2 because Ni could trap the electron during irradiation and reduce electron–hole pair recombination by the p–n junction of TiO2. The highest methanol production rate of 272. 45 μ m ol/g cat was obtained over 4% wt Ni/TiO2 catalyst, which was 20 times hig...

Engineering and Applied Science Research, 2016

Vanillin synthesis from lignin degradation using catalytic hydrothermal process over Fe 2 O 3 /Al... more Vanillin synthesis from lignin degradation using catalytic hydrothermal process over Fe 2 O 3 /Al 2 O 3 catalyst was investigated. The Fe 2 O 3 /Al 2 O 3 catalyst was prepared by wetness impregnation. The prepared catalysts were characterized by using XRD and BET method. The lignin degradation reaction was carried out in a batch high-pressure reactor. The effects of initial pressure, reaction temperature, and catalyst loading on vanillin yield were studied. It was found that an increasing of temperature gave an increasing of vanillin yield. However, the increasing of pressure and a number of catalyst loading showed the decrease of vanillin production due to the oxidation of produced vanillin to another product. The highest vanillin concentration of 8.54 mg/L was obtained at 160 oC, 2 bars, and 0.5 g of the catalyst.

Reactive dye has generally been used in woven cotton fabric dyeing industries. Some treatments of... more Reactive dye has generally been used in woven cotton fabric dyeing industries. Some treatments of several reactive dyes may produce more toxicity than the original dyes. The objectives of this study were to find the optimal condition on dye degradation efficiency of commercial reactive red dye 36 (DR36) and reactive violet dye 30 (DV30) using Fenton-like reaction, and to determine acute toxicity by static bioassay method under the optimal condition. The experiment was designed by Box Behnken Design (BBD), in which an initial pH, catalyst dosage and initial concentration of H2O2 were considered as independent variables. The results showed that only an initial pH solution was the principal parameter which influenced decolorization of the reactive dyes. Other factors were much less significant. The optimal conditions were found to be given by pH 3, 1 g/L of catalyst dosage, 27.63 mM of concentration of H2O2 for DR36, and pH 3, 1.35 g/L of catalyst dosage, 45 mM of concentration of H2O2...

This research investigates the results of catalytic methanol dehydration for synthesis of dimethy... more This research investigates the results of catalytic methanol dehydration for synthesis of dimethyl ether using chromium on diatomite catalyst with different the metal loading. The reactions were performed in pack-bed reactor at temperature between 250 to 350°C. According to the experimental results, the conversion of methanol increased with the increase of chromium loading on diatomite catalyst. DME selectivity was up to 99 percent. The surface acidity increased due to chromium loading, whereas the surface areas decreased. It was found that metal oxide loading and surface acidity affected reaction rates more than the surface area of the catalyst. Finally, 15%Cr/DM catalyst give high methanol conversion at 91.7 percent and it has exhibited good stability during the 12 hour experiment. The catalyst has shown efficient synthesis of dimethyl ether from methanol.

Applied Environmental Research, Mar 29, 2023

Environmental Science and Pollution Research

Materials Today: Proceedings

Energy Reports, 2020

Abstract This work was to optimize operating parameters for phenol production via partial oxidati... more Abstract This work was to optimize operating parameters for phenol production via partial oxidation. The essential settings, NaOH loading of 4–20 g/L, reaction temperatures of 140–180 °C, and time of 15–45 min, were set as the independent parameters for designing the experiments. A set of tests was generated using Box–Behnken Design (BBD) and performed in a high-pressure reactor at the constant air pressure of 2 bars. A produced phenol concentration was assigned as a response target for evaluating an optimal condition. From the results, a quadratic model of actual data was fit with high accuracy (R2 of 94.1%). A response surface methodology (RSM) was used to evaluate the operating parameters effect on the phenol formation. It showed that the temperature rising affected phenol formation due to the creation of aldehydes at low temperatures and phenol re-polymerization. The presence of NaOH plays an essential role in the production of phenol. It may increase the hydroxyl group’s rate to an aromatic ring that yields a high percentage of phenol production. For the reaction time, the longer time gave a higher yield of phenol. However, it slightly increased after 30 min. The predicted optimal condition was determined at the temperature of 161 °C, the NaOH loading of 16.4 mg/L, and the reaction time of 36.2 min. Three experiments were performed at the optimal point to verify the prediction. It was found that the phenol concentration of 30 ± 1 mg/L was yielded at this condition. Moreover, the reaction temperature and the initial pressure of air were not severe. It indicates that the partial oxidation of aqueous lignin solution can produce phenol at mild conditions.

Journal of the Japan Institute of Energy

This study aimed to investigate the effects of the reaction time and temperature on the hydrolysi... more This study aimed to investigate the effects of the reaction time and temperature on the hydrolysis of sucrose to glucose and fructose using an Amberlyst-15 catalyst. The experiments were conducted in a 100 mL highpressure batch reactor. The initial sucrose concentration of 500 g/L, initial nitrogen pressure of 101.3 kPa, and catalyst loading of 0.2 g remained constant during the reactions. An increase in the reaction temperature and time, which varied in the range of 303-373 K and 1-12 h, respectively, resulted in an increase in the glucose and fructose yields owing to the high acidity of Amberlyst-15. The most elevated glucose and fructose yields based on carbon moles of 0.50 mol-C/mol-C and 0.49 mol-C/mol-C, respectively, were obtained at 373 K after 3 h with complete sucrose conversion. Moreover, Amberlyst-15 was reused for more than 24 cycles, with complete sucrose conversion and a high yield of inverted sugar. Therefore, Amberlyst-15 is an active, selective, and stable catalyst for sucrose hydrolysis.

Brazilian Journal of Chemical Engineering, 2009

RH-MCM-41 was synthesized by using silica from rice husk and further modified to increase acidity... more RH-MCM-41 was synthesized by using silica from rice husk and further modified to increase acidity by adding Al with grafting method with Si/Al ratio of 75 and 25. The resulting materials were referred to as RH-AlMCM-41(75) and RH-AlMCM-41(25). The XRD spectra of all RH-AlMCM-41 confirmed a mesoporous structure of MCM-41. Surface areas of all RH-AlMCM-41 were in the range of 700-800 m 2 /g, lower than that of the parent RH-MCM-41, which was 1230 m 2 /g. After Al addition the Si/Al ratios of RH-AlMCM-41(75) and RH-AlMCM-41(25) were higher than that of the parent RH-MCM-41. The RH-AlMCM-41 materials were used as supports for bimetallic platinum−iron catalysts, denoted as Pt-Fe/RH-AlMCM-41, with Pt and Fe amounts of 0.5 and 5.0% by weight, respectively. Results from TPR indicated that the presence of Al might assist the interaction between Pt and Fe as the reduction temperature of iron oxides shifted to a lower value. All catalysts were active for phenol hydroxylation using H 2 O 2 as an oxidant, for which the highest conversions were observed on the RH-MCM-41 material with the highest surface area. The acidity of the supports did not present a significant role in improving the catalytic performance.

Nihon Enerugī Gakkaishi, Mar 20, 2022

The photocatalytic reduction of carbon dioxide into methanol over modified SiO2-Al2O3 supported T... more The photocatalytic reduction of carbon dioxide into methanol over modified SiO2-Al2O3 supported TiO2 catalyst at atmospheric pressure was investigated. The SiO2-Al2O3 supported TiO2 catalyst was modified by coating the bimetallic metal (Ni-Cu) using the sol-gel method with various Ni-Cu loading in the range of 0wt.% to 5wt.%. All prepared catalysts were characterized using Scanning electron microscopy (SEM), X-ray powder diffraction (XRD), N2 adsorption-desorption, UV-vis diffuse reflectance spectrometer (UV-Vis-DRS), and Photoluminescence Spectroscopy (PL). The reaction was performed in a liquid-phase batch-reactor equipped with a UVC lamp (125W) as a source of UV radiation. The reactions were tested at atmospheric pressure and the temperature of 25 °C for 5 h with a catalyst loading of 4 g/L. It was found that the coating of bimetallic metal had effects on the reduction of surface area and energy bandgap. The prepared catalyst had a surface area in the range 108 m 2 /g to 199.6 m 2 /g, and the bandgap energy varied from 3.01 eV to 3.08 eV. The presence of Ni (3wt.%) and Cu (2wt.%) on the TiO2/ SiO2-Al2O3 catalyst had slower recombination rate of electron-hole pairs than that of TiO2/SiO2-Al2O3 catalyst. The highest methanol production rate of 405.08 µmol/g cat was obtained after 2 h over 3wt.%Ni-2wt.%Cu-TiO2/SiO2-Al2O3. This production rate was three times higher than that over unmodified TiO2/SiO2-Al2O3 due to good retardation of electron-hole pair recombination.

Journal of the Japan Institute of Energy, 2020

This work aimed to optimize lignin conversion to vanillin by hydrothermal method. An experiment w... more This work aimed to optimize lignin conversion to vanillin by hydrothermal method. An experiment was designed by Box-Benhken Design (BBD). Temperature, NaOH concentration, and reaction time were chosen as independent parameters for achieving the optimum reaction condition. The reaction products were analyzed by highperformance liquid chromatography. Based on the experimental results, the optimum condition for the hydrothermal process was predicted using the response surface method. The maximum vanillin production of 18.1 mg/L was predicted at the optimum condition given by the temperature of 142 °C, NaOH concentration of 9.2 g/L, and reaction time of 32 min. The conversion of lignin to vanillin was experimented using the predicted optimal condition to verify the prediction. It was found that the hydrothermal method at the optimum condition yielded 18.1 ± 2 mg/L of vanillin, which was in good agreement with the predicted value. It was also found that the yield of vanillin was influenced by temperature, NaOH concentration, and the interaction of both parameters, whereas the reaction time was much less influential.

Advanced Materials Research, 2014

Aniline was removed by photocatalysis reaction using zinc oxide (ZnO, ZnO/Al2O3 and ZnO/SiO2) as ... more Aniline was removed by photocatalysis reaction using zinc oxide (ZnO, ZnO/Al2O3 and ZnO/SiO2) as catalysts. The oxidation reactions were carried out in a batch reactor. The experiment was designed by Pleckett-Burman Full Factorial Design (FFD) for screening test. The FFD was used to factors screening of 3 factors: wt% of ZnO, catalyst loading and UV light source on aniline removal. The equation model for factors screening was well fitted to the experiment data, which was observed by R2 coefficient of 0.95. The results show that wt% of ZnO and catalysts loading were the significant effects. The highest percentage aniline removal of 82.7% was achieved at the reaction condition; 0.5g of ZnO catalyst and 30wt%ZnO under UV-C irradiation. Moreover, it was found that Pleckett-Burman FFD was useful in factor screening of the aniline removal by photochemical reaction over ZnO-based catalysts.

Advanced Materials Research, 2014

The goal of this research was to synthesize two different catalysts, namely K-OMS-2 and MnOx. The... more The goal of this research was to synthesize two different catalysts, namely K-OMS-2 and MnOx. The K-OMS-2 was an octahedral manganese complex prepared by hydrothermal method, while manganese oxide (MnOx) was directly synthesized by precipitation method. Both catalysts were employed to decompose toluene, an organic solvent that is widely used in industries. The catalysts were characterized by means of X-ray diffraction (XRD) and N2-physorption. The surface areas of K-OMS-2 and MnOx were 83.50 and 20.04 m2/g, respectively. The precipitation route gave XRD patterns of γ-Mn2O3 structure, and a successful structure of an octahedral molecular sieve manganese oxide was obtained by the hydrothermal method. The toluene degradation was carried out in gas hourly space velocity (GHSV) range of 20,000-60,000 h-1 with toluene concentration of 7,700 ppmv. The higher GHSV over K-OMS-2 gave the lower contact time consequently resulting in the lower %toluene degradation, whereas the best GHSV over γ-...

Key Engineering Materials, 2013

Adsorption of Zn(II) and Pb(II) from aqueous solution were studied by using modified coir pith as... more Adsorption of Zn(II) and Pb(II) from aqueous solution were studied by using modified coir pith as an adsorbent. The extended adsorption conditions were investigated as a function of calcination temperature, contact time, adsorbent size, initial pH of solution and initial Zn(II) and Pb(II) concentrations. The adsorption capacity increased rapidly in first 5 minute and reached equilibrium in 120 minutes for Zn(II) and 10 minutes for Pb(II). In case of Zn(II); the results showed that the calcination temperature of modified coir pith above 600oC gave the higher adsorption capacity. The sizes of modified coir pith have no effect on the adsorption capacity. The adsorption capacity increased with increasing initial solution pH value. In case of Pb(II); the calcination temperature of modified coir pith showed no effect on the adsorption capacity. The sizes of modified coir pith showed a little effect on the adsorption capacity. The adsorption capacity increased with increasing of initial so...

Journal of Renewable Materials

Isosorbide is a multipurpose chemical that can be produced from renewable resources. Specifically... more Isosorbide is a multipurpose chemical that can be produced from renewable resources. Specifically, it has been investigated as a replacement for toxic bisphenol A (BPA) in the production of polycarbonate (PC). In this study, the synthesis of isosorbide by sorbitol dehydration using a cerium-based catalyst derived from calcined cerium (IV) sulfate (300°C, 400°C, 450°C, 500°C, and 650°C) was investigated. The reaction occurred in a high-pressure reactor containing nitrogen gas. Advanced instrumental techniques were applied to analyze the characteristics of the calcined catalyst. The results showed that the calcined catalysts demonstrated different crystalline structures and sulfate species at different temperatures. However, the acidic properties (strength and amount) of the catalyst did not change with the calcination temperature. The cerium (IV) sulfate calcined at 400°C exhibited the best catalytic performance, achieving the highest isosorbide yield (55.7%) and complete conversion of sorbitol at 180°C, 20 bar of N 2 , and 6 h using CeSO-400. The presence of a sulfate group on the catalyst was the most important factor in determining the catalytic performance of sorbitol dehydration to isosorbide. This work suggests that CeSO-400 catalysts may play an important role in reducing reaction conditions.

Nihon Enerugī Gakkaishi, Mar 20, 2022

This research aimed to study the photocatalytic reduction of CO2 into methanol over TiO2 supporte... more This research aimed to study the photocatalytic reduction of CO2 into methanol over TiO2 supported on SiO2-Al2O3 catalysts. The effects of reaction time and the influence of copper (1-4 %wt) doped on SiO2-Al2O3 on the methanol yield were investigated. The experiments were carried out in a 50 ml batch reactor under UV irradiation. The catalysts prepared by the sol-gel method were characterized by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The result indicated that the maximum of methanol production was obtained after the irradiation of 2 h and slightly reduced after that, probably due to the methanol oxidation process. The highest methanol production of 1258.8 µmol gcat-1 was obtained when 2%wt Cu-TiO2/SiO2-Al2O3 catalyst. This was 5.98 times that obtained from the undoped photocatalyst. The presence of the CuO phase could separate the electron from the TiO2 conduction band to move into the CuO conduction band. However, the high content of CuO could increase the TiO2 crystal size. Moreover, the catalysts could be reused seven times for the purpose. Therefore, the result of this research indicated the potential of using Cu with TiO2/SiO2-Al2O3 catalyst for reducing CO2 emission to the environment.

Journal of the Japan Institute of Energy

Energy Reports, 2020

Photocatalytic reduction of carbon dioxide into methanol fuel over the Ni-doped TiO2 catalyst has... more Photocatalytic reduction of carbon dioxide into methanol fuel over the Ni-doped TiO2 catalyst has been investigated. The experiments were carried out in a 50 ml batch reactor under UV irradiation. Ni/TiO2 photocatalysts were prepared by an impregnation method. The properties of the catalyst were characterized by X-ray photoelectron spectroscopy (XPS), UV–Vis diffuse reflectance (UV–DR). Moreover, the effect of reaction time and Ni loading on the methanol conversion were investigated. The result indicated that the maximum of methanol production was obtained after the irradiation of 3 h and slightly reduced due to the methanol oxidation process. The Ni loading catalyst showed the higher methanol concentration than that over undoped TiO2 because Ni could trap the electron during irradiation and reduce electron–hole pair recombination by the p–n junction of TiO2. The highest methanol production rate of 272. 45 μ m ol/g cat was obtained over 4% wt Ni/TiO2 catalyst, which was 20 times hig...

Engineering and Applied Science Research, 2016

Vanillin synthesis from lignin degradation using catalytic hydrothermal process over Fe 2 O 3 /Al... more Vanillin synthesis from lignin degradation using catalytic hydrothermal process over Fe 2 O 3 /Al 2 O 3 catalyst was investigated. The Fe 2 O 3 /Al 2 O 3 catalyst was prepared by wetness impregnation. The prepared catalysts were characterized by using XRD and BET method. The lignin degradation reaction was carried out in a batch high-pressure reactor. The effects of initial pressure, reaction temperature, and catalyst loading on vanillin yield were studied. It was found that an increasing of temperature gave an increasing of vanillin yield. However, the increasing of pressure and a number of catalyst loading showed the decrease of vanillin production due to the oxidation of produced vanillin to another product. The highest vanillin concentration of 8.54 mg/L was obtained at 160 oC, 2 bars, and 0.5 g of the catalyst.

Reactive dye has generally been used in woven cotton fabric dyeing industries. Some treatments of... more Reactive dye has generally been used in woven cotton fabric dyeing industries. Some treatments of several reactive dyes may produce more toxicity than the original dyes. The objectives of this study were to find the optimal condition on dye degradation efficiency of commercial reactive red dye 36 (DR36) and reactive violet dye 30 (DV30) using Fenton-like reaction, and to determine acute toxicity by static bioassay method under the optimal condition. The experiment was designed by Box Behnken Design (BBD), in which an initial pH, catalyst dosage and initial concentration of H2O2 were considered as independent variables. The results showed that only an initial pH solution was the principal parameter which influenced decolorization of the reactive dyes. Other factors were much less significant. The optimal conditions were found to be given by pH 3, 1 g/L of catalyst dosage, 27.63 mM of concentration of H2O2 for DR36, and pH 3, 1.35 g/L of catalyst dosage, 45 mM of concentration of H2O2...

This research investigates the results of catalytic methanol dehydration for synthesis of dimethy... more This research investigates the results of catalytic methanol dehydration for synthesis of dimethyl ether using chromium on diatomite catalyst with different the metal loading. The reactions were performed in pack-bed reactor at temperature between 250 to 350°C. According to the experimental results, the conversion of methanol increased with the increase of chromium loading on diatomite catalyst. DME selectivity was up to 99 percent. The surface acidity increased due to chromium loading, whereas the surface areas decreased. It was found that metal oxide loading and surface acidity affected reaction rates more than the surface area of the catalyst. Finally, 15%Cr/DM catalyst give high methanol conversion at 91.7 percent and it has exhibited good stability during the 12 hour experiment. The catalyst has shown efficient synthesis of dimethyl ether from methanol.