The adsorption of Pb(II)on silica gel synthesized from chemical glass bottle waste has been studied.The effect of independent variables(adsorbent dose,initial concentration of Pb(II),contact time,and pH)on the Pb(II)r...The adsorption of Pb(II)on silica gel synthesized from chemical glass bottle waste has been studied.The effect of independent variables(adsorbent dose,initial concentration of Pb(II),contact time,and pH)on the Pb(II)removal from water was evaluated and optimized using the Response Surface Methodology(RSM).Under optimized conditions(adsorbent dose:20 mg;contact time:30 min;initial Pb(II)concentration:120 mg.L^(−1);and pH:8),the removal of Pb(II)was 99.77%.The adsorption equilibrium data obtained from the batch experiment were investigated using different isotherm models.The Langmuir isotherm model fits the experimental data.This shows that the surface of the silica gel synthesized from chemical bottles waste was covered by a Pb(II)monolayer.XRF analysis showed that the synthesized silica gel had a SiO_(2) content of 75.63%.Amorphous silica was observed from XRD analysis.SEM-EDX characterization showed that Pb was adsorbed on the silica gel surface.SEM analysis showed that silica gel has irregular particles with a surface area of 297.08 m2.g^(−1) with a pore radius of 15.74 nm calculated from BET analysis.展开更多
Response surface (RSM) methodology based on a three-level three-factor Box-Behnkendesign of experiment was used to optimize the exopolysaccharide content (EPC) and themycelium biomass in submerged cultivation by Clito...Response surface (RSM) methodology based on a three-level three-factor Box-Behnkendesign of experiment was used to optimize the exopolysaccharide content (EPC) and themycelium biomass in submerged cultivation by Clitocybe sp. AS 5.112. The criticalfactors selected for the investigation were cultivation temperature, time and volume ofmedium, based on the results of previous Plackett-Burman design. By analyzing theresponse surface plots, the optimum ranges of cultivation temperature, time and mediumvolume for obtaining over 1 253.00gmL-1 of EPC lie in 24.325.8℃, 9.710.2d and 76.090.0mL, respectively. While for obtaining over 8.32 mg mL-1 of dry cell weight (DCW), theabove variables would be in the range of 23.824.8℃, 9.610.3d and 71.098.0mL,respectively. By solving the inverse matrix from the quadratic regression equations, theoptimal conditions to gain 1 265.45gmL-1 of EPC were 25.0℃, 9.9d and 83.4mL, to gain8.50mg mL-1 of DCW were 24.4℃, 9.9d and 87.1mL. In order to obtain the maximum yield ofEPC and DCW at the same time, the above conditions would be 24.5℃, 9.9d and 84.7mL,respectively, in this situation, the maximum predicted EPC and DCW were 1 261.60gmL-1and 8.47mgmL-1, respectively. The experimental data under various conditions have validatedthe theoretical values.展开更多
In this work the effects of the contents of nickel (5, 7.5, 10 wt%) and copper (0, 1, 2 wt%) and reac- tion temperature (650, 700, 750 ℃) on the catalytic performance of Ni-Cu/Al_2O_3 catalyst in methane dry re...In this work the effects of the contents of nickel (5, 7.5, 10 wt%) and copper (0, 1, 2 wt%) and reac- tion temperature (650, 700, 750 ℃) on the catalytic performance of Ni-Cu/Al_2O_3 catalyst in methane dry reforming were evaluated using Box-Behnken design in order to optimize methane conversion, H_2/CO ratio and the catalyst deactivation. Different catalysts were prepared by co-impregnation method and characterized by XRD, BET, H_2-TPR, FESEM and TG/DTA analyses. The results revealed that copper addi- tion improved the catalyst reducibility. Promoted catalyst with low amounts of Cu gave higher activity and stability with high resistance to coke deposition and agglomeration of active phase especially during the reaction. However catalysts with high amounts of Cu were less active and rather deactivated due to the active sites sintering as well as Ni covering by Cu-enriched phase. The optimal conditions were de- termined by desirability function approach as 10 wt% of Ni, 0.83 wt% of Cu at 750℃. CH_4 conversion of 95.1%, H_2/CO ratio of 1 and deactivation of 1.4% were obtained experimentally under optimum conditions, which were in close agreement with the values oredicted hv the developed model.展开更多
Electrospun poly(vinyl alcohol)/chitosan nanofibers had their solution and process parameters optimized using a Box-Behnken design and desirability function. Four factors (applied voltage, flow rate, distance tip-to-p...Electrospun poly(vinyl alcohol)/chitosan nanofibers had their solution and process parameters optimized using a Box-Behnken design and desirability function. Four factors (applied voltage, flow rate, distance tip-to-plate and amount of chitosan) were varied to produce electrospun mats with a low fiber diameter. An empirical model was developed for each response using response surface methodology (RSM), which revealed that flow rate had no significant influence on the assessed responses. With desirability function, the optimal conditions to produce the nanofibers were applied voltage of 13.1 kV, 30% chitosan concentration and distance tip-to-plate of 10 cm. The fiber diameter and standard deviation were 196.5 ± 28.3 nm, compared to the predicted values of 185.9 ± 26.8 nm. The desirability function allied with Box-Benhken design proved themselves important tools to predict process parameters for the development of nanofibers. The mats were crosslinked with glutaraldehyde for 24 h and 48 h and presented good water stability and enhanced mechanical properties.展开更多
This research focuses on the effective removal of methylene blue dye using silica gel synthesized from chemical glass bottle waste as an environmentally friendly and cost-effective adsorbent.The adsorption process was...This research focuses on the effective removal of methylene blue dye using silica gel synthesized from chemical glass bottle waste as an environmentally friendly and cost-effective adsorbent.The adsorption process was optimized using Box-Behnken Design(BBD)and Response Surface Methodology(RSM)to investigate the influence of pH(6;8 and 10),contact time(15;30 and 45 min),adsorbent mass(30;50 and 70 mg),and initial concentration(20;50 and 80 mg/L)of the adsorbate on the adsorption efficiency.The BBD was conducted using Google Colaboratory software,which encompassed 27 experiments with randomly assigned combinations.The silica gel synthesized from chemical glass bottle was characterized by XRD,FTIR,SEM-EDX and TEM.The adsorption result was measured by spectrophotometer UV-Vis.The optimized conditions resulted in a remarkable methylene blue removal efficiency of 99.41%.Characterization of the silica gel demonstrated amorphous morphology and prominent absorption bands characteristic of silica.The Langmuir isotherm model best described the adsorption behavior,revealing chemisorption with a monolayer coverage of methylene blue on the adsorbent surface,and a maximum adsorption capacity of 82.02 mg/g.Additionally,the pseudo-second-order kinetics model indicated a chemisorption mechanism during the adsorption process.The findings highlight the potential of silica gel from chemical glass bottle waste as a promising adsorbent for wastewater treatment,offering economic and environmental benefits.Further investigations can explore its scalability,regenerability,and reusability for industrial-scale applications.展开更多
文摘The adsorption of Pb(II)on silica gel synthesized from chemical glass bottle waste has been studied.The effect of independent variables(adsorbent dose,initial concentration of Pb(II),contact time,and pH)on the Pb(II)removal from water was evaluated and optimized using the Response Surface Methodology(RSM).Under optimized conditions(adsorbent dose:20 mg;contact time:30 min;initial Pb(II)concentration:120 mg.L^(−1);and pH:8),the removal of Pb(II)was 99.77%.The adsorption equilibrium data obtained from the batch experiment were investigated using different isotherm models.The Langmuir isotherm model fits the experimental data.This shows that the surface of the silica gel synthesized from chemical bottles waste was covered by a Pb(II)monolayer.XRF analysis showed that the synthesized silica gel had a SiO_(2) content of 75.63%.Amorphous silica was observed from XRD analysis.SEM-EDX characterization showed that Pb was adsorbed on the silica gel surface.SEM analysis showed that silica gel has irregular particles with a surface area of 297.08 m2.g^(−1) with a pore radius of 15.74 nm calculated from BET analysis.
文摘Response surface (RSM) methodology based on a three-level three-factor Box-Behnkendesign of experiment was used to optimize the exopolysaccharide content (EPC) and themycelium biomass in submerged cultivation by Clitocybe sp. AS 5.112. The criticalfactors selected for the investigation were cultivation temperature, time and volume ofmedium, based on the results of previous Plackett-Burman design. By analyzing theresponse surface plots, the optimum ranges of cultivation temperature, time and mediumvolume for obtaining over 1 253.00gmL-1 of EPC lie in 24.325.8℃, 9.710.2d and 76.090.0mL, respectively. While for obtaining over 8.32 mg mL-1 of dry cell weight (DCW), theabove variables would be in the range of 23.824.8℃, 9.610.3d and 71.098.0mL,respectively. By solving the inverse matrix from the quadratic regression equations, theoptimal conditions to gain 1 265.45gmL-1 of EPC were 25.0℃, 9.9d and 83.4mL, to gain8.50mg mL-1 of DCW were 24.4℃, 9.9d and 87.1mL. In order to obtain the maximum yield ofEPC and DCW at the same time, the above conditions would be 24.5℃, 9.9d and 84.7mL,respectively, in this situation, the maximum predicted EPC and DCW were 1 261.60gmL-1and 8.47mgmL-1, respectively. The experimental data under various conditions have validatedthe theoretical values.
文摘In this work the effects of the contents of nickel (5, 7.5, 10 wt%) and copper (0, 1, 2 wt%) and reac- tion temperature (650, 700, 750 ℃) on the catalytic performance of Ni-Cu/Al_2O_3 catalyst in methane dry reforming were evaluated using Box-Behnken design in order to optimize methane conversion, H_2/CO ratio and the catalyst deactivation. Different catalysts were prepared by co-impregnation method and characterized by XRD, BET, H_2-TPR, FESEM and TG/DTA analyses. The results revealed that copper addi- tion improved the catalyst reducibility. Promoted catalyst with low amounts of Cu gave higher activity and stability with high resistance to coke deposition and agglomeration of active phase especially during the reaction. However catalysts with high amounts of Cu were less active and rather deactivated due to the active sites sintering as well as Ni covering by Cu-enriched phase. The optimal conditions were de- termined by desirability function approach as 10 wt% of Ni, 0.83 wt% of Cu at 750℃. CH_4 conversion of 95.1%, H_2/CO ratio of 1 and deactivation of 1.4% were obtained experimentally under optimum conditions, which were in close agreement with the values oredicted hv the developed model.
文摘Electrospun poly(vinyl alcohol)/chitosan nanofibers had their solution and process parameters optimized using a Box-Behnken design and desirability function. Four factors (applied voltage, flow rate, distance tip-to-plate and amount of chitosan) were varied to produce electrospun mats with a low fiber diameter. An empirical model was developed for each response using response surface methodology (RSM), which revealed that flow rate had no significant influence on the assessed responses. With desirability function, the optimal conditions to produce the nanofibers were applied voltage of 13.1 kV, 30% chitosan concentration and distance tip-to-plate of 10 cm. The fiber diameter and standard deviation were 196.5 ± 28.3 nm, compared to the predicted values of 185.9 ± 26.8 nm. The desirability function allied with Box-Benhken design proved themselves important tools to predict process parameters for the development of nanofibers. The mats were crosslinked with glutaraldehyde for 24 h and 48 h and presented good water stability and enhanced mechanical properties.
基金funded by Directorate of Research and Community Service(DRPM,Direktorat Riset dan Pengabdian Kepada Masyarakat)ITS through the ITS Research Local Grant(No.1727/PKS/ITS/2023).
文摘This research focuses on the effective removal of methylene blue dye using silica gel synthesized from chemical glass bottle waste as an environmentally friendly and cost-effective adsorbent.The adsorption process was optimized using Box-Behnken Design(BBD)and Response Surface Methodology(RSM)to investigate the influence of pH(6;8 and 10),contact time(15;30 and 45 min),adsorbent mass(30;50 and 70 mg),and initial concentration(20;50 and 80 mg/L)of the adsorbate on the adsorption efficiency.The BBD was conducted using Google Colaboratory software,which encompassed 27 experiments with randomly assigned combinations.The silica gel synthesized from chemical glass bottle was characterized by XRD,FTIR,SEM-EDX and TEM.The adsorption result was measured by spectrophotometer UV-Vis.The optimized conditions resulted in a remarkable methylene blue removal efficiency of 99.41%.Characterization of the silica gel demonstrated amorphous morphology and prominent absorption bands characteristic of silica.The Langmuir isotherm model best described the adsorption behavior,revealing chemisorption with a monolayer coverage of methylene blue on the adsorbent surface,and a maximum adsorption capacity of 82.02 mg/g.Additionally,the pseudo-second-order kinetics model indicated a chemisorption mechanism during the adsorption process.The findings highlight the potential of silica gel from chemical glass bottle waste as a promising adsorbent for wastewater treatment,offering economic and environmental benefits.Further investigations can explore its scalability,regenerability,and reusability for industrial-scale applications.