Pub Date : 2025-12-01Epub Date: 2025-01-24DOI: 10.1016/j.clce.2025.100149
Maryam Iranpour , Ali Babaei , Mojtaba Bagherzadeh
This study investigates, for the first time, the inhibitory capabilities of Melilotus officinalis extract (MOE), extracted via microwave-assisted (MAE) and heat-assisted extraction (HAE), in preventing corrosion of carbon steel (CS) in a 0.5 M HCl solution. Utilized methodologies include conventional weight loss techniques and electrochemical analyses like Tafel polarization and electrochemical impedance spectroscopy (EIS) for measuring MOE's inhibition efficiency (IE) on CS. The adsorption behaviors of MOE on the CS surface were evaluated through different adsorption isotherm models. Additionally, the study assessed the effect of temperature on the extracted MOE's IE% and polarization actions, providing thermodynamic parameters (Ea, ΔS*, and ΔH*) for CS in the acidic solution, both with and without MOE presence. The maximum IE% achieved was 92.3% when the concentration of MOE extracted via the MAE route reached 800 ppm, following a duration of 30 min, as determined by EIS measurements. Finally, surface protection offered by MOE to CS in the acidic solution was verified using scanning electron microscopy (SEM). The results of the study are reviewed and analyzed comprehensively.
本研究首次研究了微波辅助萃取（MAE）和热辅助萃取（HAE）两种萃取方法提取的木耳提取物（MOE）在0.5 M HCl溶液中对碳钢（CS）的腐蚀抑制能力。使用的方法包括传统的减重技术和电化学分析，如塔菲尔极化和电化学阻抗谱（EIS）来测量MOE对CS的抑制效率（IE）。通过不同的吸附等温线模型评价了MOE在CS表面的吸附行为。此外，研究还评估了温度对提取的MOE的IE%和极化作用的影响，提供了在有和没有MOE存在的酸性溶液中CS的热力学参数（Ea， ΔS*和ΔH*）。通过EIS测量，当MAE提取的MOE浓度达到800 ppm，持续时间为30 min时，最大IE%达到92.3%。最后，通过扫描电镜（SEM）验证了MOE在酸性溶液中对CS的表面保护作用。对研究结果进行了综述和综合分析。
{"title":"Microwave and heat-assisted extracted Melilotus officinalis as a potential eco-friendly corrosion inhibitor for carbon steel in 0.5 M HCl solution","authors":"Maryam Iranpour , Ali Babaei , Mojtaba Bagherzadeh","doi":"10.1016/j.clce.2025.100149","DOIUrl":"10.1016/j.clce.2025.100149","url":null,"abstract":"<div><div>This study investigates, for the first time, the inhibitory capabilities of Melilotus officinalis extract (MOE), extracted via microwave-assisted (MAE) and heat-assisted extraction (HAE), in preventing corrosion of carbon steel (CS) in a 0.5 M HCl solution. Utilized methodologies include conventional weight loss techniques and electrochemical analyses like Tafel polarization and electrochemical impedance spectroscopy (EIS) for measuring MOE's inhibition efficiency (IE) on CS. The adsorption behaviors of MOE on the CS surface were evaluated through different adsorption isotherm models. Additionally, the study assessed the effect of temperature on the extracted MOE's IE% and polarization actions, providing thermodynamic parameters (Ea, ΔS*, and ΔH*) for CS in the acidic solution, both with and without MOE presence. The maximum IE% achieved was 92.3% when the concentration of MOE extracted via the MAE route reached 800 ppm, following a duration of 30 min, as determined by EIS measurements. Finally, surface protection offered by MOE to CS in the acidic solution was verified using scanning electron microscopy (SEM). The results of the study are reviewed and analyzed comprehensively.</div></div>","PeriodicalId":100251,"journal":{"name":"Cleaner Chemical Engineering","volume":"11 ","pages":"Article 100149"},"PeriodicalIF":0.0,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143162096","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-01Epub Date: 2025-05-14DOI: 10.1016/j.clce.2025.100182
Jannatun Zia , Amit Kumar Shringi , Ufana Riaz
This study presents a sustainable and innovative strategy for waste reutilization and environmental remediation through the green synthesis of calcium oxide (CaO) nanoparticles (NPs) derived from waste eggshells, predominantly composed of calcium carbonate. The CaO NPs were synthesized via a straight forward calcination process and characterized using X-ray diffraction (XRD), scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDX), Fourier-transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), and UV–visible diffuse reflectance spectroscopy (UV–Vis DRS). XRD confirmed high crystallinity with an average crystallite size of 32 nm, while TEM revealed cubic nanoparticles in the range of 30–50 nm. TGA analysis demonstrated notable thermal stability up to 800 °C.The catalytic performance of the synthesized CaO NPs was evaluated via microwave-assisted degradation of Malachite Green (MG), a model organic pollutant. Under microwave irradiation, CaO NPs achieved 86 % degradation within 30 min, significantly outperforming raw eggshells (72 %). The degradation followed pseudo-first-order kinetics. Optimization studies revealed enhanced degradation efficiency (up to 93.40 %) at 900 W microwave powers and 94.59 % efficiency with a catalyst dose of 250 mg/L. However, increasing MG concentration from 20 to 50 mg/L resulted in a decline in degradation efficiency from 86 % to 60.2 %. Recyclability assessments showed 77 % degradation efficiency after four consecutive cycles, indicating the catalyst’s stability and reusability. Scavenger experiments identified the involvement of reactive species, including hydroxyl radicals (•OH), superoxide anions (•O₂⁻), and photo-generated holes (h⁺), in the degradation mechanism. Furthermore, LC-MS analysis proposed a plausible degradation pathway based on intermediate m/z values. Compared to conventional thermal or chemical degradation methods, the microwave-assisted catalytic process using CaO NPs demonstrated superior efficiency, rapid reaction kinetics, and reduced energy consumption. This work highlights the potential of converting bio-waste into high-value nanomaterials for scalable, eco-friendly, and cost-effective wastewater treatment applications.
{"title":"Calcium oxide nanoparticles from eggshell waste: A green nanotechnological strategy for microwave-assisted environmental clean up","authors":"Jannatun Zia , Amit Kumar Shringi , Ufana Riaz","doi":"10.1016/j.clce.2025.100182","DOIUrl":"10.1016/j.clce.2025.100182","url":null,"abstract":"<div><div>This study presents a sustainable and innovative strategy for waste reutilization and environmental remediation through the green synthesis of calcium oxide (CaO) nanoparticles (NPs) derived from waste eggshells, predominantly composed of calcium carbonate. The CaO NPs were synthesized via a straight forward calcination process and characterized using X-ray diffraction (XRD), scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDX), Fourier-transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), and UV–visible diffuse reflectance spectroscopy (UV–Vis DRS). XRD confirmed high crystallinity with an average crystallite size of 32 nm, while TEM revealed cubic nanoparticles in the range of 30–50 nm. TGA analysis demonstrated notable thermal stability up to 800 °C.The catalytic performance of the synthesized CaO NPs was evaluated via microwave-assisted degradation of Malachite Green (MG), a model organic pollutant. Under microwave irradiation, CaO NPs achieved 86 % degradation within 30 min, significantly outperforming raw eggshells (72 %). The degradation followed pseudo-first-order kinetics. Optimization studies revealed enhanced degradation efficiency (up to 93.40 %) at 900 W microwave powers and 94.59 % efficiency with a catalyst dose of 250 mg/L. However, increasing MG concentration from 20 to 50 mg/L resulted in a decline in degradation efficiency from 86 % to 60.2 %. Recyclability assessments showed 77 % degradation efficiency after four consecutive cycles, indicating the catalyst’s stability and reusability. Scavenger experiments identified the involvement of reactive species, including hydroxyl radicals (•OH), superoxide anions (•O₂⁻), and photo-generated holes (h⁺), in the degradation mechanism. Furthermore, LC-MS analysis proposed a plausible degradation pathway based on intermediate <em>m/z</em> values. Compared to conventional thermal or chemical degradation methods, the microwave-assisted catalytic process using CaO NPs demonstrated superior efficiency, rapid reaction kinetics, and reduced energy consumption. This work highlights the potential of converting bio-waste into high-value nanomaterials for scalable, eco-friendly, and cost-effective wastewater treatment applications.</div></div>","PeriodicalId":100251,"journal":{"name":"Cleaner Chemical Engineering","volume":"11 ","pages":"Article 100182"},"PeriodicalIF":0.0,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144071285","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In the present study, electrochemistry based electro-coagulation (EC) process, known as green process is used for the decolorization of Reactive Blue 4 (RB4) from simulated textile wastewater. A multivariate approach, response surface methodology (RSM) and central composite design (CCD) is employed to model and optimize the EC process with five input variables (pH, initial concentration of dye, current density, operating time, and electrodes gap) to treat the wastewater containing RB 4 dye. The efficiency of EC process is calculated in terms of % decolorization and % chemical oxygen demand (COD) removal. A back-propagation Artificial Neural Network (BP - ANN) is also engaged to predict the % color and % COD removal. The experimental values of % decolorization (89.3 %) and % COD removal (84.3 %) are found very close to predicted % decolorizations (88.6 % and 89.4 %) and % COD removal (83.4 % and 84.4 %) at optimized conditions [pH (X1) = 7.0; initial dye concentration (X2) = 1297.6 mg l-1; current density (X3) = 13.42 mA cm-2; contact time (X4) = 70 min and initial electrodes gap (X5) = 1.0 cm] using RSM and ANN, respectively. Techno-economic efficacy is determined in terms of an operating cost as ₹114.82 m-3. The physico-chemical properties of the EC process generated sludge are analyzed using FTIR and FESEM/EDX. The comparative analysis with previous studies and future perspectives of the EC process for the removal of RB 4 from wastewater is also carried out.
{"title":"Electrochemical treatment of wastewater containing reactive Blue 4 (RB 4) dye: RSM and ANN optimization, technoeconomic analysis and sludge characterization","authors":"Kajal Gautam , Yatindra Kumar , Shriram Sonawane , Sushil Kumar","doi":"10.1016/j.clce.2024.100138","DOIUrl":"10.1016/j.clce.2024.100138","url":null,"abstract":"<div><div>In the present study, electrochemistry based electro-coagulation (EC) process, known as green process is used for the decolorization of Reactive Blue 4 (RB4) from simulated textile wastewater. A multivariate approach, response surface methodology (RSM) and central composite design (CCD) is employed to model and optimize the EC process with five input variables (pH, initial concentration of dye, current density, operating time, and electrodes gap) to treat the wastewater containing RB 4 dye. The efficiency of EC process is calculated in terms of % decolorization and % chemical oxygen demand (COD) removal. A back-propagation Artificial Neural Network (BP - ANN) is also engaged to predict the % color and % COD removal. The experimental values of % decolorization (89.3 %) and % COD removal (84.3 %) are found very close to predicted % decolorizations (88.6 % and 89.4 %) and % COD removal (83.4 % and 84.4 %) at optimized conditions [pH (<em>X<sub>1</sub></em>) = 7.0; initial dye concentration (<em>X<sub>2</sub></em>) = 1297.6 mg <span>l</span><sup>-1</sup>; current density (<em>X<sub>3</sub></em>) = 13.42 mA cm<sup>-2</sup>; contact time (<em>X<sub>4</sub></em>) = 70 min and initial electrodes gap (<em>X<sub>5</sub></em>) = 1.0 cm] using RSM and ANN, respectively. Techno-economic efficacy is determined in terms of an operating cost as ₹114.82 m<sup>-3</sup>. The physico-chemical properties of the EC process generated sludge are analyzed using FTIR and FESEM/EDX. The comparative analysis with previous studies and future perspectives of the EC process for the removal of RB 4 from wastewater is also carried out.</div></div>","PeriodicalId":100251,"journal":{"name":"Cleaner Chemical Engineering","volume":"11 ","pages":"Article 100138"},"PeriodicalIF":0.0,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143161614","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-01Epub Date: 2025-04-08DOI: 10.1016/j.clce.2025.100168
Ali Darvish Falehi
The Proton Exchange Membrane Fuel Cell (PEMFC) is one of the most important eco-friendly energy conversion systems which provides electrical energy from chemical energy as a consequence of electrochemical reaction. The performance, accuracy and durability of PEMFC-based power generation system are strongly dependent on its control strategy and design methodology, which may be a challenging and complex task owing to all-inclusive dynamic mechanism of air conditioning system. This paper aims to propose a new Chattering Free Binomial Hyperbolic Sliding Mode Controller (CFBHSMC) for DC-DC boost converter to augment the system performance and guarantee the system accuracy in presence of model uncertainties and external disturbances. Due to nonlinearity of PEMFC system and its high control sensitivity, the design control scheme has been formulated as multi-objective optimization problem using Multi-Objective Stochastic Fractal Search Algorithm (MOSFSA). The optimal CFBHSMC can significantly reduce the chattering effect, ensure the fast convergence and enhance the tracking accuracy. To validate the proposed controller's capabilities, the simulation results have been compared with fuzzy controller, classic SMC and super-twisting SMC. The simulation results have revealed that the oscillation ranges of PEMFC system for fuzzy controller, classic SMC, super-twisting SMC and CFBHSMC are respectively achieved 8 × 10–3, 9 × 10–3, 4 × 10–3 and 2 × 10–4, and also the average deviations of these oscillations from the reference signal are respectively obtained as 14×10–3, 5 × 10–3, 2 × 10–3 and 1 × 10–4.
{"title":"MOSFSA-based CFBHSMC to enhance control accuracy and robustness of proton exchange membrane fuel cell>","authors":"Ali Darvish Falehi","doi":"10.1016/j.clce.2025.100168","DOIUrl":"10.1016/j.clce.2025.100168","url":null,"abstract":"<div><div>The Proton Exchange Membrane Fuel Cell (PEMFC) is one of the most important eco-friendly energy conversion systems which provides electrical energy from chemical energy as a consequence of electrochemical reaction. The performance, accuracy and durability of PEMFC-based power generation system are strongly dependent on its control strategy and design methodology, which may be a challenging and complex task owing to all-inclusive dynamic mechanism of air conditioning system. This paper aims to propose a new Chattering Free Binomial Hyperbolic Sliding Mode Controller (CFBHSMC) for DC-DC boost converter to augment the system performance and guarantee the system accuracy in presence of model uncertainties and external disturbances. Due to nonlinearity of PEMFC system and its high control sensitivity, the design control scheme has been formulated as multi-objective optimization problem using Multi-Objective Stochastic Fractal Search Algorithm (MOSFSA). The optimal CFBHSMC can significantly reduce the chattering effect, ensure the fast convergence and enhance the tracking accuracy. To validate the proposed controller's capabilities, the simulation results have been compared with fuzzy controller, classic SMC and super-twisting SMC. The simulation results have revealed that the oscillation ranges of PEMFC system for fuzzy controller, classic SMC, super-twisting SMC and CFBHSMC are respectively achieved 8 × 10<sup>–3</sup>, 9 × 10<sup>–3</sup>, 4 × 10<sup>–3</sup> and 2 × 10<sup>–4</sup>, and also the average deviations of these oscillations from the reference signal are respectively obtained as 14×10<sup>–3</sup>, 5 × 10<sup>–3</sup>, 2 × 10<sup>–3</sup> and 1 × 10<sup>–4</sup>.</div></div>","PeriodicalId":100251,"journal":{"name":"Cleaner Chemical Engineering","volume":"11 ","pages":"Article 100168"},"PeriodicalIF":0.0,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143842566","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-01Epub Date: 2025-04-19DOI: 10.1016/j.clce.2025.100171
N.M. Tshuma , L.B. Moyo , G. Danha , T.A. Mamvura , G.S. Simate , C.D. Artur , G. Charis
This study aims to investigate the effect blending waste material to improve its fuel properties using pressurized torrefaction. This research explored the benefits of blending animal waste with wood chips to produce a bio-coal with improved fuel properties. The process conditions investigated were temperature and pressure intervals of 200°C to 280°C and atmospheric pressure (AP) to 4MPa, respectively. The results showed that an increase in temperature and pressure improved the fixed carbon content of the blend almost threefold from 19.87 % to 66.93 % and the higher heating value (HHV) to 27.32MJ/kg from 13.90MJ/kg at mild torrefaction temperature of 280°C and gas pressure of 4MPa compared to atmospheric pressure conditions and the lowest temperature investigated. The HHV increased primarily due to a release of bound and unbound moisture and volatile matter. Wood chips had an HHV of 27.00MJ/kg at a torrefaction temperature of 280°C due to the decomposition of hemicellulose and cellulose which enhanced the thermal stability, fixed carbon content and calorific value. However, animal waste had the least incremental increase in HHV (16.45MJ/kg) due to a high initial content of volatile matter and moisture. The improved properties of the blend of materials indicated that pressurized torrefaction was effective in increasing fixed carbon content through secondary polymerization reactions. Moreover, it facilitated the decomposition of cellulose at a lower temperature than the typical range of 315-400°C if conducted at atmospheric pressure. This study elucidates the notable role of the synergistic effects of blending feed materials prior to torrefaction towards improving the properties and pyrolysis performance of biomass components.
{"title":"Pressurized torrefaction of waste biomass to improve bio coal quality: Synergistic effect between animal waste and wood chips","authors":"N.M. Tshuma , L.B. Moyo , G. Danha , T.A. Mamvura , G.S. Simate , C.D. Artur , G. Charis","doi":"10.1016/j.clce.2025.100171","DOIUrl":"10.1016/j.clce.2025.100171","url":null,"abstract":"<div><div>This study aims to investigate the effect blending waste material to improve its fuel properties using pressurized torrefaction. This research explored the benefits of blending animal waste with wood chips to produce a bio-coal with improved fuel properties. The process conditions investigated were temperature and pressure intervals of 200°C to 280°C and atmospheric pressure (AP) to 4MPa, respectively. The results showed that an increase in temperature and pressure improved the fixed carbon content of the blend almost threefold from 19.87 % to 66.93 % and the higher heating value (HHV) to 27.32MJ/kg from 13.90MJ/kg at mild torrefaction temperature of 280°C and gas pressure of 4MPa compared to atmospheric pressure conditions and the lowest temperature investigated. The HHV increased primarily due to a release of bound and unbound moisture and volatile matter. Wood chips had an HHV of 27.00MJ/kg at a torrefaction temperature of 280°C due to the decomposition of hemicellulose and cellulose which enhanced the thermal stability, fixed carbon content and calorific value. However, animal waste had the least incremental increase in HHV (16.45MJ/kg) due to a high initial content of volatile matter and moisture. The improved properties of the blend of materials indicated that pressurized torrefaction was effective in increasing fixed carbon content through secondary polymerization reactions. Moreover, it facilitated the decomposition of cellulose at a lower temperature than the typical range of 315-400°C if conducted at atmospheric pressure. This study elucidates the notable role of the synergistic effects of blending feed materials prior to torrefaction towards improving the properties and pyrolysis performance of biomass components.</div></div>","PeriodicalId":100251,"journal":{"name":"Cleaner Chemical Engineering","volume":"11 ","pages":"Article 100171"},"PeriodicalIF":0.0,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143874826","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-01Epub Date: 2025-08-24DOI: 10.1016/j.clce.2025.100204
Joel Reza, Edith Meneses-Ruiz, Patricia Pérez-Romo, Alfonso López-Ortega, Georgina C. Laredo
This study compares the performance of autogenous pressurized pyrolysis (P-PYR) and low-pressure hydrothermal liquefaction (LP-HT) for transforming low-density polyethylene (LDPE) into gasoline-range and diesel-range hydrocarbons. Both processes were carried out in a closed reactor, at temperatures from 350 to 450 °C. The effect of ZSM-5 zeolite as a catalyst was also analyzed. The evaluated parameters included the amount of the gas, oil, and wax fractions formed; the chemical composition of the gas and liquid fractions; and the simulated distillations (SIMDIS) of the liquid fractions. The distillation curves obtained by SIMDIS were used to estimate the yield of gasoline range and diesel-range hydrocarbon fractions. In the non-catalyzed processes, all the products had nearly the same composition, indicating that water had a limited effect on the depolymerization process. In the catalyzed processes, there was a slight change in the yield of the recovered products when water was present. The ZSM-5 zeolite also had an impact on the chemical composition of the produced fractions. Without the catalyst, both LP-HT and P-PYR (at 400 °C) produced about 40 % gasoline-range and 25 % diesel-range hydrocarbons, leading to a total yield of fuel-range hydrocarbons of around 65 %. When the ZSM-5 catalyst was used, the recovered oil mostly contained single-ring aromatic compounds, leading to a fuel yield of around 44 % (at 375 °C), with gasoline-range hydrocarbons making up 36–38 % and diesel-range hydrocarbons 6–8 %. The results indicate that ZSM-5 zeolite can alter the makeup of the thermochemical products from LDPE, and at the experimental conditions studied, water only had a limited effect.
{"title":"Depolymerization of LDPE under low pressure-hydrothermal processing and pressurized pyrolysis: Effect of the ZSM-5 catalyst","authors":"Joel Reza, Edith Meneses-Ruiz, Patricia Pérez-Romo, Alfonso López-Ortega, Georgina C. Laredo","doi":"10.1016/j.clce.2025.100204","DOIUrl":"10.1016/j.clce.2025.100204","url":null,"abstract":"<div><div>This study compares the performance of autogenous pressurized pyrolysis (P-PYR) and low-pressure hydrothermal liquefaction (LP-HT) for transforming low-density polyethylene (LDPE) into gasoline-range and diesel-range hydrocarbons. Both processes were carried out in a closed reactor, at temperatures from 350 to 450 °C. The effect of ZSM-5 zeolite as a catalyst was also analyzed. The evaluated parameters included the amount of the gas, oil, and wax fractions formed; the chemical composition of the gas and liquid fractions; and the simulated distillations (SIMDIS) of the liquid fractions. The distillation curves obtained by SIMDIS were used to estimate the yield of gasoline range and diesel-range hydrocarbon fractions. In the non-catalyzed processes, all the products had nearly the same composition, indicating that water had a limited effect on the depolymerization process. In the catalyzed processes, there was a slight change in the yield of the recovered products when water was present. The ZSM-5 zeolite also had an impact on the chemical composition of the produced fractions. Without the catalyst, both LP-HT and P-PYR (at 400 °C) produced about 40 % gasoline-range and 25 % diesel-range hydrocarbons, leading to a total yield of fuel-range hydrocarbons of around 65 %. When the ZSM-5 catalyst was used, the recovered oil mostly contained single-ring aromatic compounds, leading to a fuel yield of around 44 % (at 375 °C), with gasoline-range hydrocarbons making up 36–38 % and diesel-range hydrocarbons 6–8 %. The results indicate that ZSM-5 zeolite can alter the makeup of the thermochemical products from LDPE, and at the experimental conditions studied, water only had a limited effect.</div></div>","PeriodicalId":100251,"journal":{"name":"Cleaner Chemical Engineering","volume":"11 ","pages":"Article 100204"},"PeriodicalIF":0.0,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144912065","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study aims to evaluate the efficiency of the ZnO/TiO2 heterojunction in a photocatalytic process under UV-Visible irradiation for the degradation of amoxicillin (AMX), an antibiotic commonly detected as a pharmaceutical contaminant in water. The photocatalyst was synthesized by sol-gel method and characterized by various techniques such as XRD, FT-IR, SEM/EDX, MET and UV-vis DRS, in order to evaluate its physicochemical properties. Optimization of several experimental parameters, such as the initial concentration of AMX, the nature of the photocatalyst, the catalyst dose and the initial pH of the solution, was carried out to maximize photocatalytic performance. XRD revealed the presence of the wurtzite phase for ZnO, while TiO2 showed the rutile and anatase phases, finely dispersed in the ZnO matrix. FT-IR analysis confirmed the presence of the characteristic ZnO and TiO2 bands, and UV-vis DRS analysis also confirmed significant energy absorption in the UV-vis range. In addition, evaluation of photocatalytic efficiency under different experimental conditions showed that alkaline conditions were more conducive to degradation due to the significantly higher hydroxyl ion content. Under optimal experimental conditions (AMX concentration of 40 mg/L, pH of approx. 10, catalyst dose of 100 mg/L and Zn2+/Ti4+=4 molar ratio), the ZnO-TiO2 heterojunction reached 94% after 210 minutes of exposure to UV-vis irradiation, guaranteeing an optimum balance between light penetration and photocatalytic activity. In addition, the photocatalyst demonstrated high regeneration capacity and photostability, maintaining high regeneration capacity after five cycles. These results underline the strong potential of the ZnO-TiO₂ heterojunction for concrete applications in the treatment of polluted water.
{"title":"Optimization of photocatalytic degradation of amoxicillin by ZnO-TiO2 heterojunction under UV-Visible irradiation","authors":"Samira Charafi , Fatima Zahra Janani , Alaâeddine Elhalil , Mohamed Abdennouri , Mhamed Sadiq , Noureddine Barka","doi":"10.1016/j.clce.2025.100183","DOIUrl":"10.1016/j.clce.2025.100183","url":null,"abstract":"<div><div>This study aims to evaluate the efficiency of the ZnO/TiO<sub>2</sub> heterojunction in a photocatalytic process under UV-Visible irradiation for the degradation of amoxicillin (AMX), an antibiotic commonly detected as a pharmaceutical contaminant in water. The photocatalyst was synthesized by sol-gel method and characterized by various techniques such as XRD, FT-IR, SEM/EDX, MET and UV-vis DRS, in order to evaluate its physicochemical properties. Optimization of several experimental parameters, such as the initial concentration of AMX, the nature of the photocatalyst, the catalyst dose and the initial pH of the solution, was carried out to maximize photocatalytic performance. XRD revealed the presence of the wurtzite phase for ZnO, while TiO<sub>2</sub> showed the rutile and anatase phases, finely dispersed in the ZnO matrix. FT-IR analysis confirmed the presence of the characteristic ZnO and TiO<sub>2</sub> bands, and UV-vis DRS analysis also confirmed significant energy absorption in the UV-vis range. In addition, evaluation of photocatalytic efficiency under different experimental conditions showed that alkaline conditions were more conducive to degradation due to the significantly higher hydroxyl ion content. Under optimal experimental conditions (AMX concentration of 40 mg/L, pH of approx. 10, catalyst dose of 100 mg/L and Zn<sup>2+</sup>/Ti<sup>4+</sup>=4 molar ratio), the ZnO-TiO<sub>2</sub> heterojunction reached 94% after 210 minutes of exposure to UV-vis irradiation, guaranteeing an optimum balance between light penetration and photocatalytic activity. In addition, the photocatalyst demonstrated high regeneration capacity and photostability, maintaining high regeneration capacity after five cycles. These results underline the strong potential of the ZnO-TiO₂ heterojunction for concrete applications in the treatment of polluted water.</div></div>","PeriodicalId":100251,"journal":{"name":"Cleaner Chemical Engineering","volume":"11 ","pages":"Article 100183"},"PeriodicalIF":0.0,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144154680","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Freshwater scarcity remains a critical global challenge, necessitating sustainable desalination solutions. This study investigates the performance enhancement of a double-slope solar still (SS) through the integration of hollow copper coil fins (HCCFs), phase change material (PCM), and an Arduino-based water depth control system. Three configurations were tested: conventional (Case I), fin-modified (Case II), and PCM-fin with smart control (Case III). Experimental results demonstrated that Case III achieved the highest productivity, yielding 1.81 L/m²/day, a 166 % improvement over the conventional still (0.68 L/m²/day) and 14 % higher than Case II (1.59 L/m²/day). Thermal analysis revealed peak energy and exergy efficiencies of 38.9 % and 4.31 %, respectively, for Case III, significantly surpassing Cases I (23.1 %, 1.45 %) and II (28.3 %, 3.45 %). The intelligent water depth modulation (20–35 mm) optimized heat transfer, while PCM extended post-sunset distillation. Economic and environmental assessments showed a payback period of 295 days and 4.8 tons of CO₂ mitigation over the system’s lifetime, with potential carbon credits of $190. This work establishes a novel, scalable approach for sustainable solar desalination.
{"title":"Synergistic integration of PCM-filled coil fins and smart water depth control in solar stills: A comprehensive energy, exergy, and environmental analysis","authors":"Lailatul Nehar , Tanvir Rahman , Md Shahiduzzaman Shahed , Md Yeamin Prodhan , Md Sazan Rahman , S.S. Tuly","doi":"10.1016/j.clce.2025.100189","DOIUrl":"10.1016/j.clce.2025.100189","url":null,"abstract":"<div><div>Freshwater scarcity remains a critical global challenge, necessitating sustainable desalination solutions. This study investigates the performance enhancement of a double-slope solar still (SS) through the integration of hollow copper coil fins (HCCFs), phase change material (PCM), and an Arduino-based water depth control system. Three configurations were tested: conventional (Case I), fin-modified (Case II), and PCM-fin with smart control (Case III). Experimental results demonstrated that Case III achieved the highest productivity, yielding 1.81 L/m²/day, a 166 % improvement over the conventional still (0.68 L/m²/day) and 14 % higher than Case II (1.59 L/m²/day). Thermal analysis revealed peak energy and exergy efficiencies of 38.9 % and 4.31 %, respectively, for Case III, significantly surpassing Cases I (23.1 %, 1.45 %) and II (28.3 %, 3.45 %). The intelligent water depth modulation (20–35 mm) optimized heat transfer, while PCM extended post-sunset distillation. Economic and environmental assessments showed a payback period of 295 days and 4.8 tons of CO₂ mitigation over the system’s lifetime, with potential carbon credits of $190. This work establishes a novel, scalable approach for sustainable solar desalination.</div></div>","PeriodicalId":100251,"journal":{"name":"Cleaner Chemical Engineering","volume":"11 ","pages":"Article 100189"},"PeriodicalIF":0.0,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144580895","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-01Epub Date: 2025-01-11DOI: 10.1016/j.clce.2025.100146
Thiago Reschützegger, Nina Paula Gonçalves Salau
Liquid-phase adsorption, a fundamental process where molecules in a liquid medium adhere to a solid surface, plays a crucial role in various chemical engineering applications such as wastewater decontamination and solvent recovery. These phenomena can be described by equilibrium models, which offer insight into adsorption capacity and thermodynamic properties, such as enthalpy and entropy variations, yet parameter uncertainty often undermines their accuracy. This study applies a Bayesian approach to assess uncertainties within adsorption models quantitatively and qualitatively. Through Bayesian analysis, substantial parameter variability was identified in the Sips model, with posterior distributions for thermodynamic parameters revealing broad uncertainty regions and a high likelihood of exothermic enthalpy values (i.e. ), which often deviate from established thermodynamic expectations across different systems. Despite achieving good fit statistics (e.g., R² ≈ 0.99), this flexibility in the Sips model does not consistently translate into reliable thermodynamic interpretations. In contrast, the Langmuir model yields more stable estimates, offering narrower and thermodynamically consistent probability distributions for equilibrium constants (e.g., ΔH° > 0 and ΔS° > 0) and Gibbs free energy changes across temperature variations, albeit with slightly lower fit statistics (e.g., R² ≈ 0.97). These findings highlight the need for uncertainty analysis in model selection and advise caution in attributing physical significance to isotherm-derived parameters. This study advocates for a balanced approach to model choice, incorporating uncertainty quantification to enhance the reliability of adsorption predictions in both research and industrial applications.
{"title":"Uncertainty impact of isotherm models on liquid-phase adsorption thermodynamics: A bayesian inference perspective","authors":"Thiago Reschützegger, Nina Paula Gonçalves Salau","doi":"10.1016/j.clce.2025.100146","DOIUrl":"10.1016/j.clce.2025.100146","url":null,"abstract":"<div><div>Liquid-phase adsorption, a fundamental process where molecules in a liquid medium adhere to a solid surface, plays a crucial role in various chemical engineering applications such as wastewater decontamination and solvent recovery. These phenomena can be described by equilibrium models, which offer insight into adsorption capacity and thermodynamic properties, such as enthalpy and entropy variations, yet parameter uncertainty often undermines their accuracy. This study applies a Bayesian approach to assess uncertainties within adsorption models quantitatively and qualitatively. Through Bayesian analysis, substantial parameter variability was identified in the Sips model, with posterior distributions for thermodynamic parameters revealing broad uncertainty regions and a high likelihood of exothermic enthalpy values (i.e. <span><math><mrow><mi>P</mi><mo>(</mo><mrow><mstyle><mi>Δ</mi></mstyle><msup><mi>H</mi><mo>∘</mo></msup><mo><</mo><mn>0</mn></mrow><mo>)</mo><mo>></mo><mn>0.5</mn></mrow></math></span>), which often deviate from established thermodynamic expectations across different systems. Despite achieving good fit statistics (e.g., R² ≈ 0.99), this flexibility in the Sips model does not consistently translate into reliable thermodynamic interpretations. In contrast, the Langmuir model yields more stable estimates, offering narrower and thermodynamically consistent probability distributions for equilibrium constants (e.g., ΔH° > 0 and ΔS° > 0) and Gibbs free energy changes across temperature variations, albeit with slightly lower fit statistics (e.g., R² ≈ 0.97). These findings highlight the need for uncertainty analysis in model selection and advise caution in attributing physical significance to isotherm-derived parameters. This study advocates for a balanced approach to model choice, incorporating uncertainty quantification to enhance the reliability of adsorption predictions in both research and industrial applications.</div></div>","PeriodicalId":100251,"journal":{"name":"Cleaner Chemical Engineering","volume":"11 ","pages":"Article 100146"},"PeriodicalIF":0.0,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143162099","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A phenomenological biosorption kinetic model was developed for cesium (Cs) biosorption from radioactive wastewaters by poly-γ-glutamic acid sodium salt (γ-PGANa). The biosorption by non-living biosorbent γ-PGANa is controlled by the ion-exchange mechanism and the proposed kinetic model is based on the ion-exchange mechanism, which is disassembled in two steps, i.e., Step 1 in which Na+ from the functional group (–COONa) in γ-PGANa is released and Step 2 in which Cs+ and H+ are competitively adsorbed on negatively charged functional group −COO−. The validation of the proposed phenomenological kinetic model was conducted using the present experimental data for dynamic changes in Cs concentration obtained with the wide ranges of operation conditions at pH from 3 to 9, the dosage of γ-PGANa from 0.1 to 0.6 gL−1, the initial Cs concentration from 0.0001 to 0.1 gL−1, and temperature from 298 to 318 K. The capability of the proposed kinetic model was proved by reasonable agreement between the model predictions and the experimental results.
{"title":"Phenomenological kinetic model for biosorption of cesium (Cs) by poly-γ-glutamic acid sodium salt (γ-PGANa)","authors":"Misaki Hisada, Shigeki Sakamoto, Kenta Sugiyama, Yoshinori Kawase","doi":"10.1016/j.clce.2025.100150","DOIUrl":"10.1016/j.clce.2025.100150","url":null,"abstract":"<div><div>A phenomenological biosorption kinetic model was developed for cesium (Cs) biosorption from radioactive wastewaters by poly-γ-glutamic acid sodium salt (γ-PGANa). The biosorption by non-living biosorbent γ-PGANa is controlled by the ion-exchange mechanism and the proposed kinetic model is based on the ion-exchange mechanism, which is disassembled in two steps, i.e., Step 1 in which Na<sup>+</sup> from the functional group (–COONa) in γ-PGANa is released and Step 2 in which Cs<sup>+</sup> and H<sup>+</sup> are competitively adsorbed on negatively charged functional group −COO<sup>−</sup>. The validation of the proposed phenomenological kinetic model was conducted using the present experimental data for dynamic changes in Cs concentration obtained with the wide ranges of operation conditions at pH from 3 to 9, the dosage of γ-PGANa from 0.1 to 0.6 gL<sup>−1</sup>, the initial Cs concentration from 0.0001 to 0.1 gL<sup>−1</sup>, and temperature from 298 to 318 K. The capability of the proposed kinetic model was proved by reasonable agreement between the model predictions and the experimental results.</div></div>","PeriodicalId":100251,"journal":{"name":"Cleaner Chemical Engineering","volume":"11 ","pages":"Article 100150"},"PeriodicalIF":0.0,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143162097","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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