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16 result(s) for "Amibo, Temesgen Abeto"
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Process Optimization for Acid Hydrolysis and Characterization of Bioethanol from Leftover Injera Waste by Using Response Surface Methodology: Central Composite Design
In this study, leftover injera waste from the southwestern parts of Ethiopia was used as a raw material for bioethanol production. The conversion of this biomass into ethanol involved processing techniques, which include hydrolysis, fermentation, and distillation. This research focuses on determining optimal parameters that are temperature, acid concentration, and hydrolyzing time in a hydrolysis stage. Using response surface analysis, the suggested model is quadratic and has three independent factors, which had significant effects on the yield of ethanol. In this analysis, the temperature and hydrolyzing time had a positive relationship with the yield of ethanol whereas acid concentration had a negative relation. The optimum yield of ethanol obtained was 79.07%. The yield optimized in g/g was 29.99, which was obtained at a temperature of 109.99°C, at an acid concentration of 1.00%, and hydrolyzing time of 49.59 minutes. For this analysis, the mathematical model equation was developed and the R2 value was 99.9% and its desirability was 0.8867. The property of ethanol was characterized by the many parameters used in different standardization. The density, viscosity, flammability, boiling points, and pH were determined as 0.803 gcm−3, 1.1 cP, 14°C, 80°C, and 6.65, respectively.
Expermental investigation on adsorption of methylene blue dye from waste water using corncob cellulose-based hydrogel
Hydrogel from corncob cellulose was synthesized in this investigation. The synthesized Hydrogel was characterized by SEM, XRD, and FTIR instruments. As the results indicate the synthesized hydrogel has required and important features, these suggest the suitability of hydrogel for the adsorption of methylene blue dye (MBD). Three important process variables (dosage, contact time, and initial concentration) with three levels were studied during the adsorption process at 30 °C and neutral pH. The efficiency of hydrogel for adsorption of MBD was determined in each experiment. The experimental results were statistically analyzed and interpreted. The maximum removal efficiency was achieved at 2.22 g/L of dosage, 80.36 min of contact time, and 74.54 mg/L of initial concentration. At this condition, 98.25% of MBD was achieved through experimental tests. Kinetics, isotherm, and thermodynamics studies were performed. Langmuir isotherm is more suitable to describe the adsorption process and the Pseudo second-order kinetic model fits this process. From the thermodynamics studies, all negative values of change in Gibbs free energy (ΔG°), and positive value of change in enthalpy (ΔH°), and change in entropy (ΔS°) indicate that the carried out experimental process is a spontaneous and endothermic. Moreover, the regeneration experiment for adsorbent was performed. The treatment of real textile industry waste water was conducted and the removal efficiency of hydrogel was 64.76%. This removal percentage reduction from sythetic aqueous solution is due to involvement of other pollutants in the real waste water. The synthesized hydrogel adsorbent is suitable up to the third cycle without significant loss in removal efficiency.
Process optimization and modeling research for the defluoridation of water using a novel adsorbent of cellulose and hydroxyapatite nanocomposite
According to world health organization fluoride ion concentration in the drinking water greater than 1.5 mg/L results in humans healthy risks. In this research, a cellulose/hydroxyapatite nanocomposite was produced and used for fluoride ions removal from water by adsorption. To synthesize the nanocomposite, cellulose of African alpine bamboo ( Yushuania alpina ) and (ii) hydroxyapatite of chicken eggshells were used. The adsorbent characteristics were determined based on dynamic light scattering, Brunauer-Emmett-Teller, scanning electron microscopy, Fourier transform infrared spectroscopy, x-ray diffraction, thermogravimetric analysis and derivative thermogravimetric analysis. Adsorption experiments were designed by the central composite design approach. The influence of an adsorbent dose (0.075–1.75 g/L), pH (5–9), contact time (40–80 min) and initial fluoride ion concentration (20–40 mg/L) were investigated. The highest adsorption capacity of the adsorbent was 23.02 mg/g. The highest removal efficiency of 98.68% was attained by employing dosage of 1.43 g/L for 77 min, at a pH of 5.24, and with an initial concentration of 24.43 mg/L. Thermodynamic analysis shows that the process is spontaneous and endothermic, as confirmed by the positive values of ΔH° and ΔS°, and the negative values of ΔG°. The adsorption process can be described the pseudo-second-order kinetic model and the Langmuir isotherm. The study showed that the cellulose/hydroxyapatite nanocomposite is an environmentally friendly and effective adsorbent for fluoride ion removal.
Production and Optimization of Bio-Based Silica Nanoparticle from Teff Straw (Eragrostis tef) Using RSM-Based Modeling, Characterization Aspects, and Adsorption Efficacy of Methyl Orange Dye
The brown teff straw was utilized in this study to produce silica using the sol-gel technique. After pretreatment, the raw material of brown teff straw was characterized. The data were analyzed using the central composite design and response surface technique, and four independent parameters, namely, temperature, NaOH concentration, rotational speed, and extraction time, were evaluated for process optimization. Before extracting silica with an alkaline solution, the silica content in the ash was determined using an AAS spectrometer. The silica content of teff straw ash is around 92.89%. The ash was treated with NaOH solution in the concentrations range of 1 M to 3 M (0.5 M interval). The extraction time varied at intervals of 55, 70, 85, 100, and 115 minutes. Temperatures were changed using magnetic stirrer equipment in the range of 80°C to 100°C (5°C interval). At 350 rpm, 400 rpm, 450 rpm, 500 rpm, and 550 rpm, the rotating speed was adjusted. The best extraction conditions for amorphous silica were 1.50 M NaOH, 109.99 min, 94.98°C, and a rotating speed of 499.57 rpm, with a maximum yield of 85.85%. XRD and FTIR analyses were used to assess the physicochemical characteristics of the extracted silica. The aqueous solutions of methyl orange were used to test the adsorption efficiency of silica. The percent of removal efficiency for methyl orange was 90.48%.
Synthesis and application of biomass-derived magnetic biochar catalyst for simultaneous esterification and trans-esterification of waste cooking oil into biodiesel: modeling and optimization
This work created, characterized, and used a magnetic biochar catalyst that is both eco-friendly and very effective. Sugarcane bagasse was selected as primary raw material for catalyst preparation, because it is renewable and ecofriendly biomass. Catalyst created by doping sugarcane bagasse biochar with magnetic material in the form of (FeSO4·7H2O). Thermogravimetric Analysis (TGA) and Fourier Transform Infrared spectroscopy (FTIR) were used to characterize the catalyst. In addition, physical and textural characteristics of the catalyst were identified and interpreted. The characterization outcome showed that the catalyst has good catalytic qualities. For the manufacturing of biodiesel, discarded cooking oil served as the primary feedstock. The experiment was created utilizing the Box–Behnken Design (BBD) technique. There are four variables with the following three levels each: temperature, methanol to oil ratio, catalyst concentration, and reaction time. 29 experiments in total were carried out. Using the RSM function, optimization was done. The optimal conditions for obtaining biodiesel yield—temperature, methanol to oil ratio, reaction time, and catalyst weight—were 43.597 °C, 9.975 mol/L, 49.945 min, and 1.758 wt%. A study of the produced biodiesel using a FTIR showed that the conventional biodiesel IR spectra were confirmed. All physiochemical characteristics found suggested the biodiesel complied with ASTM and EN norms. Overall, the synthesized catalyst had conducted simultaneous reactions in a single batch reactor and had demonstrated suitability for converting used cooking oil to biodiesel.
Optimizing of Nanocellulose Extraction From Highland Bamboo Arundinaria Alpina for Sustainable Bio‐Nanomaterials via Response Surface Methodology
Nanocellulose (NC) extraction from agricultural waste and lignocellulosic biomass residues has drawn considerable interest due to its low cost and wide availability. The environmental issues linked to nonrenewable materials have underscored the need for renewable alternatives that are biocompatible, biodegradable, and eco‐friendly. This study aimed to investigate the potential of Ethiopian highland bamboo Arundinaria alpina for NC extraction by using acid hydrolysis. An experimental design incorporating response surface methodology (RSM) was applied to identify the optimal hydrolysis process parameters for NC extraction. The optimum conditions for NC extraction were a reaction time of 60 min, temperature of 40°C, and acid concentration of 61.40 wt%, with a yield of 43.15%. Bamboo and extracted NC were characterized for their chemical composition, particle size distribution, and crystallinity, using Fourier‐transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), and X‐ray diffraction (XRD), respectively. The resulting NC had a particle size of 79.64 nm. XRD analysis revealed the crystallinity indices of the bamboo and its corresponding NC was 44.60% and 74.07%, respectively. These results indicate that highland bamboo A. alpina is a promising lignocellulosic source for sustainable NC extraction, optimization, and industrial applications.
Novel Lanthanum Doped Magnetic Teff Straw Biochar Nanocomposite and Optimization Its Efficacy of Defluoridation of Groundwater Using RSM: A Case Study of Hawassa City, Ethiopia
The problem extent of the large concentration of fluoride ions in drinking water is still a central health issue. In the present study, lanthanum doped magnetic Teff straw biochar (LDMTSB) was developed as a novel adsorbent for removing fluoride ions in the groundwater in Rift-Valley regions, especially Hawassa city, Ethiopia. The synthesized LDMTBC was characterized via FTIR, XRD, SEM, and BET. And, this analysis proposed that multiadsorption techniques such as ligand exchange, precipitations, and electrostatic interaction could be evinced throughout the fluoride ions adsorption process by LDMTSB. The constraints that influence the adsorption efficacy, namely, a dosage of LDMTSB, contact time, pH of the solution, and rotational speed, were analyzed and optimized using the response surface methodology approach. Under the optimum situations, LDMTSB dosage: 3.97 g, contact time: 56.36 min, rotational speed: 591.19 rpm, and pH: 3.968 demonstrate high efficacy of LDMTSB with 98.89% fluoride removal capacity. Further, the quadratic model (R2 = 0.9841) was designated for governing the mathematical process. The LDMTSB was successful in the removal of fluoride ions in the groundwater. This study provides a valuable economical solution for the application of Teff straw.
Adsorptive Capacity of Calcinated Hen Eggshell Blended with Silica Gel for Removal of Lead II Ions from Aqueous Media: Kinetics and Equilibrium Studies
In this study, a description was given for the adsorbent CaSiO3 for allure proximate examination and determination like particle density, main part density, and porosity analysis. This is performed before management of batch adsorption experiments. Both kinetics and balance studies for the adsorbent were examined. The influences of various process parameters like lead concentration, pH, adsorbent dosage, and contact temporal length for process removal were explored. The removal efficiency of CaO from eggshell was enhanced to increase after mixing it with silica coagulate compared with added scholar’s findings for the same limit. The maximum removal efficiency (99.58%) was obtained by limiting the pH, adsorbent dosage, initial lead concentration, and contact time at 4, 1.8 g, 35 g/L, and 140 minutes, respectively. Thus, blending CaO from eggshells with silica gel can increase the adsorption competency of CaO. Lead removal is well integrated into the Langmuir isotherm model with an equivalent factor of 0.991. The kinetic data of adsorption fit well into a pseudo-first-order model with a correlation coefficient of 0.90111. The pseudo-second-order model was the rate-determining step involved in the lead adsorption process for calcium silicate (CaSiO3) adsorbents.
Optimization of adsorption of methyl orange from aqueous solution by magnetic CoFe2O4/ZnAl-layered double hydroxide composite using response surface methodology
The CoFe2O4/ZnAl-layered double hydroxide (LDH) composite was successfully developed through a facile co-precipitation method, characterized, and applied as an effective adsorbent for the removal of methyl orange (MO) dye from aqueous solutions. The central composite design (CCD) of the response surface methodology (RSM) was employed to estimate and optimize process variables such as initial MO concentrations, solution pH, adsorbent dosage, and contact time. 98.878% adsorption efficiency was obtained at an initial concentration of 18.747 mg l−1 of MO, with an adsorbent dosage of 0.048 g, a solution pH of 2.770, and a contact time of 85.890 min. Analysis of variance (ANOVA) confirmed the significance of the predicted model (R2 = 0.9844). Kinetic and equilibrium studies indicated that the experimental data for MO adsorption were best described by pseudo-second-order kinetic and Langmuir models. The maximum monolayer adsorption capacity of the CoFe2O4/ZnAl-LDH for MO was 42.3 mg g−1.
Wastewater Treatment Using a Photoelectrochemical Oxidation Process for the Coffee Processing Industry Optimization of Chemical Oxygen Demand (COD) Removal Using Response Surface Methodology
The elimination of organic compounds in coffee processing effluent utilizing electrochemical oxidation (ECO) as well as a combination of electrochemical oxidation (ECO) and ultraviolet and hydrogen peroxide (UV/H2O2) was explored. Then, the percentage reduction of chemical oxygen demand (COD) was investigated. The effect of different experimental factors such as solution pH, sodium chloride (NaCl) concentration, calcium chloride (CaCl2) concentration, electric current, electrolysis duration, and hydrogen peroxide dosage on the percent removal efficiency of the hybrid electrochemical oxidation (ECO) with the ultraviolet and hydrogen peroxide (UV/H2O2) process has been investigated. The response surface methodology (RSM) based on central composite design (CCD) was used to organize the trial runs and optimize the results. The hybrid electrochemical oxidation (ECO) with the ultraviolet and hydrogen peroxide (UV/H2O2) process removed 99.61% of the chemical oxygen demand (COD) with a low power usage of 1.12 kWh/m3 compared to the other procedures, according to the experimental data analysis. These findings were obtained with a pH of 7, a current of 0.40 A, 1.5 g of CaCl2, and a total electrolysis period of 40 minutes. When it came to eliminating organic compounds from coffee manufacturing effluent, CaCl2 outperformed NaCl. Analysis of variance (ANOVA) with 95% confidence limits was used to examine the significance of independent variables and their interactions.