Kinetic Analysis Research Articles

Kinetic analysis and model evaluation for steam co-gasification of coal-biomass blended chars using macro-TGA

Kinetic analysis and model evaluation for steam co-gasification of coal-biomass blended chars using macro-TGA

High temperature capture of CO2 on Li4SiO4 sorbents via a simple dry ball-milling coupled with K2CO3 physical addition

The reversible CO2 absorption/desorption of lithium orthosilicate (Li4SiO4) sorbents holds potential for high temperature capture of CO2 from hot flue gases, sorption-enhanced reforming and solar thermochemical energy storage. In this study, we have prepared a series of Li4SiO4 sorbents using a combination of K2CO3 addition and dry ball-milling procedure to improve the relatively slow kinetics under low CO2 partial pressure conditions. The synergistic effects of dry ball-milling and K2CO3 addition on the intrinsic properties of Li4SiO4 sorbents were explored by thermogravimetric analysis and structural characterizations. Thermogravimetric analysis indicate that the highest CO2 uptakes were achieved with dry ball-milling combined with K2CO3 physical addition. The structural characterizations further reveal that this sorbent (P-3K-1.5 M) had the smallest crystallite/particle size, largest surface area, and highest availability of surface alkaline-sites. The kinetics analysis also demonstrates that P-3K-1.5 M exhibited the fastest sorption kinetics during a double process. Additionally, P-3K-1.5 M maintained a high capacity over 10 sorption/desorption cycles. Therefore, this synthesis technique, which is simple, cost-effective, and easily scalable, shows great promise for high-temperature CO2 capture.

Application of metal organic frameworks ZIF-8-based solid catalyst with hierarchical porous structure and Brønsted-Lewis dual acid sites ionic liquids for sustainable biodiesel production from acidic soybean oil

In order to alleviate the mass transfer limitation of triglyceride macromolecules on the solid catalyst surface during the catalytic oil transformation process, the utilization of hierarchical porous solid catalyst is a feasible method. For reaching this goal, the hierarchical porous support of H-ZIF-8 was initially prepared by incorporating the three-dimensional ordered macro and mesoporous into the ZIF-8 using polystyrene spheres (PS) as a hard template. Subsequently, the phosphotungstate anion PW12O403- (PW) decorated sulfonated 4,4'-dipyridinium ionic liquid with Keggin structure, namely [DPySO3H]1.5PW, was encapsulated in the H-ZIF-8 support, with the formation of the novel [DPySO3H]1.5PW@H-ZIF-8 catalyst. The so-synthesized solid catalysts featured with ordered hierarchical porous structure and dual Lewis and Brønsted acidic properties, with large BET surface area of 267.38 m2/g. This catalyst had high catalytic performances for the concurrent transformation of triglycerides and free fatty acids to biodiesel in a heterogeneous manner. Under the optimal reaction parameters (methanol/oil molar ratio: 30:1; catalyst dosage: 4 wt%; reaction time: 8 h; reaction temperature: 130 °C), the oil conversion level of 91.2% and entire conversion of free fatty acids could be attained by applying this [DPySO3H]1.5PW@H-ZIF-8 catalyst. The high catalytic activity of this catalyst was due primarily to the increased mass transfer efficiency and synergism of Lewis and Brønsted acid sites. Moreover, the good FFA and moisture-resistance capacity was also shown for this catalyst even in the case of moisture content of 5 % and FFA content of 40 % in the oil feedstock. This solid catalyst could be reused by simple filtration and displayed good reusability, still attaining over 80% oil conversion at the fourth reuse cycles thanks to the robust interactions between the acidic active centers and the hierarchical porous support. The kinetic analysis indicated that the activation energy Ea and Arrhenius constant A for this solid acid-catalyzed transesterification process were 56.0 kJ/mol and 7.8×104 min-1, respectively. This research would provide a new approach for the development of hierarchical porous solid catalysts, enabling the one-step transformation of low-grade acidic oils into biodiesel in a more sustainable and environmentally friendly way.

Effects of freezing of gait on vertical ground reaction force in Parkinson's disease

Vertical ground reaction force (vGRF) is a main kinetic gait analysis explaining body weight loading patterns. The study primarily aimed to understand effects of Freezing of gait (FoG) on vGRF in Parkinson's disease (PD). A secondary analysis for a walking dataset including biomechanical analyses for 26 PD participants (13 with FoG) was performed. Considering the normal pattern of vGRF curve, peaks during early stance (F1) and late stance (F3), and slope in- during mid-stance (F2) were used to represent the change in kinetic forces. vGRF parameters were compared between FoG and non-FoG participants, and at off- and on-medication. FoG participants showed higher vGRFs during mid-stance F2 magnitude (p = 0.003), and weaker vertical propulsion; F3 magnitude (p < 0.001). This coincided with delayed weight acceptance; F1 timing (p = 0.019), and midstance peaks; F2 timing (p = 0.004). At off-medications, the F2 magnitude was significantly higher (p = 0.006), F3 magnitude lower (p = 0.001), and F1 time slower (p = 0.034) in FoG. At on-medication, F3 magnitude was still significantly lower (p = 0.017), and F2 time was slower (p = 0.037) in FoG. This study reveals that FoG significantly affects vGRF, particularly F3 magnitude during the push-off phase. Analyzing vGRF is crucial for understanding and managing FoG, allowing for more targeted interventions to improve FoG outcomes.

Pyrolysis kinetics and thermodynamic analysis of bamboo, bagasse, and rice husk bio-chars: Implications for sustainable energy

This study focuses on the kinetic and thermodynamic analysis of bio-chars derived from popular and abundantly available biomasses like bamboo, bagasse, and rice husk. These bio-chars obtained by pyrolysis aim to be utilised without any refinement for combustion purposes minimising greenhouse gases and contributing towards sustainable development goals. However, understanding the kinetic and thermodynamic properties of bio-char is essential for optimizing its combustion performance. The results indicate a marked improvement in fixed carbon content and calorific value compared to the original biomass, alongside a reduction in average activation energy. For example, bamboo bio-char exhibited an increase in fixed carbon content from 16.02 % to 68.28 %, a rise in higher heating value from 16.84 to 25.48 MJ/kg, and a decrease in average activation energy from 183.63 to 121.22 kJ/mol in comparision to bamboo biomass. Additionally, the study introduces a novel approach that combines model-free and model-fitting techniques to simultaneously determine the reaction mechanism and pre-exponential factor such that the need for separate validation ends. This novel methodology offers a state-of-the-art framework for assessing the bioenergy potential of various biomasses, applicable for studies and comparisons on a global scale.

Adsorption Models and Kinetic Analysis of Molybdenum on the Sediment of the Yellow River in China

Adsorption Models and Kinetic Analysis of Molybdenum on the Sediment of the Yellow River in China

Efficient CO2 adsorption by deoiled flaxseed hydrochar.

This study optimizes CO2 adsorption using hydrochar from de-oiled flaxseed (FDOP), a waste byproduct of the oil extraction industry, through hydrothermal carbonization (HTC). The aim is to enhance CO2 capture sustainably and cost-effectively. Using Response Surface Methodology (RSM), in optimal conditions achieved 1153.26mg/g CO2 adsorption capacity under 215.15°C synthesis temperature, 3.05h synthesis time, 0.99M acid concentration, 8.997bar pressure, and 25.07°C adsorption temperature. Statistical analysis (F-value: 44.48, R²: 0.9705) confirmed strong model reliability. Kinetic analysis showed both physical and chemical adsorption, while thermodynamic analysis revealed exothermic behavior (ΔH° values: -46.697kJ/mol for M-225, -40.230kJ/mol for MA-203). After 10 regeneration cycles, the adsorption capacity was reduced by only 2.8% and 3.1%, indicating excellent recyclability. This study highlights FDOP-derived hydrochar as a highly efficient, low-cost adsorbent, offering industrial applications for carbon capture and waste management.

Rate-Controlled Washing of Surface-Modified Nanoparticles Using Rationally Designed Supercritical CO2 Media.

In practical applications of surface-modified nanoparticles (NPs), the washing stage has a number of challenges, such as insufficient washing, long treatment time, and various waste liquors. Cosolvent-enhanced supercritical CO2 (scCO2) is an appealing solvent system for complete, rapid, and eco-friendly washing owing to its high diffusivity and recyclability. In this paper, we report a rapid washing guideline for surface-modified NPs using ethanol-enhanced scCO2. Kinetic analysis was performed on the washing behavior of oleic acid-modified NPs mixed with various modifiers (C10 to C18 fatty acids) at 40 °C and 20.0 MPa while designing scCO2 media based on rationally estimated modifier solubilities. Notably, the scCO2 medium showed superior washing rates to that of ethanol for various modifiers with a wide range of solubilities in scCO2. The washing rate was dependent on solubility and could be organized into two regions, with a threshold value of 0.016 mol kg-1: solubility/diffusivity-controlled and diffusivity-controlled washing. These findings provide valuable guidelines for designing cosolvent-enhanced scCO2 media for the rapid washing of surface-modified NPs.

EVALUATION OF THE ANTIOXIDATIVE EFFICACY OF FULLERENE SOOT DOPED BY C60/C70 (85/15) FOR LOW-DENSITY/HIGH PRESSURE POLYETHYLENE NANOCOMPOSITES

Fullerenes (C60-70) although effective stabilizers-antioxidants for polymeric materials they have not yet found widespread practical application because of their high cost. As such, polymer manufacturers prefer to use classical stabilizers. In order to try to overcome this situation for some useful applications here the evaluation of relatively cheap fullerene soot (FS) doped additionally by C60/C70(85/15) is undertaken. Solution kinetic studies on the inhibition of model cumene oxidation combined with the thermal and mechanical analysis of the FS+C60/C70 integrated in a low-density/high pressure polyethylene (LDPE) matrix demonstrates the obvious advantage of a such an approach. The kinetic analysis made on the model reaction of initiated oxidation of cumene showed that the antioxidant activity of samples of fullerene carbon black doped with fullerenes C60-70 exhibits inhibition rate constants with high enough values comparable to those of strong industrial antioxidants such as Irganox 1010/1076. The additional portions of C60-70 fullerenes slightly increase the commercial cost of the FS itself, while the higher efficiency of the modified fullerene samples shown by thermal and mechanical analysis prevails more and allows us to recommend them for the industrial use at a measured optimal concentration of 1%w/w in the polymer

Biochemical properties of immobilized horseradish peroxidase on ceramic and its application in removal of azo dye.

In the current work, electrostatic interactions were used to immobilize the horseradish peroxidase (HRP) onto five types of ceramic materials (C) with different concentrations of oxidized metals (C1-C5). The highest immobilization efficiency (70 and 77%) was detected at 6mg C3 and 18 enzyme units. Scanning Electron Microscope (SEM), Energy Dispersive X-ray (EDX) and Fourier Transform Infrared (FTIR) analysis of C3-HRP confirmed the immobilization of the enzyme. After ten reuses, the reusability analysis showed that (66%) of the C3-HRP enzyme activity was retained. For C3-HRP, the optimum pH and temperature of the soluble enzyme were shifted from 7.0 and 30°C to 6.0 and 50°C. Up to 40°C and 50°C, respectively, the soluble HRP and C3-HRP remained steady. The kinetic analysis revealed that the Km and Vmax of soluble HRP and C3-HRP were, respectively, 5.5mM, 0.66 units, and 8mM, 0.52 units for hydrogen peroxide (H2O2) and 35.5mM, 3.4 units and 40mM, 1.1 units for guaiacol. Compared to soluble-HRP, the C3-HRP exhibited a greater oxidizing affinity toward several phenolic compounds (Guaiacol, o-dianisidine, o-phenylenediamine, pyrogallol, p-aminoantipyrine). In comparison with soluble-HRP, the C3-HRP showed increased stress tolerance with Triton X-100, urea, metals, isopropanol, and dimethyl sulfoxide. The C3-HRP removed methyl orange more effectively compared to soluble-HRP.

Thermal degradation of polytetrafluoroethylene, modified polytetrafluoroethylene, and their nanocomposites with boron nitride nanobarbs: Lifetime predictions and kinetic analysis

AbstractFlexible polymeric materials including dielectric thermal interface materials (TIMs) used in integrated circuits and other high frequency applications are exposed to extreme thermal and electrical conditions during their service life. Insight into the in‐use thermal stability and material lifetime is valuable to maintaining performance durability and preventing premature failure in actual end use. Herein, the thermal stability of polytetrafluoroethylene (PTFE), modified PTFE and their nanocomposites with recent generation boron nitride nanobarbs (BNNBs) was investigated based on lifetime prediction from thermogravimetric analysis and tensile strength deterioration of heat‐aged samples. Additionally, thermal degradation kinetics and mechanism was investigated using the model‐free advanced isoconversional method based on changing activation energy. The result shows that BNNB extends the lifetime of the PTFE by an order of magnitude. The degradation mechanism proposed from TGA‐MS result is supported by the multistep degradation mechanism identified in the kinetic computation. These results are valuable for predicting materials' in‐use lifetime to avoid premature failure.

Impact of Gas Accumulation on the Stability of Parallel Upward Ventilation in High-Temperature Sloped Shafts of Deep Wells

To explore the causes and influencing factors of wind flow oscillations in high-temperature inclined aisles of deep wells under parallel upward ventilation, this study conducts a comprehensive investigation using theoretical analysis and numerical simulations. Based on the kinetic analysis of gas flow, a discriminant formula for wind flow reversal in the side branch is derived. Further analysis identifies initial wind speed and branch length as key factors influencing the reversal. Both gas pressure and thermal pressure contribute to wind flow reversal in the side branch, and the opposing directions of these pressures cause high-temperature gas to periodically flow between the two branches, resulting in wind flow oscillations. A higher initial wind speed can effectively reduce the oscillation amplitude due to increased initial kinetic energy and a larger pressure difference, but it does not extend the oscillation duration. Increasing the branch length can suppress wind flow oscillations by increasing airflow frictional resistance and damping.

Thermal Oxidation Degradation Characteristics and Kinetic Analysis of Waste Shell Powders for Efficient Utilization and Environmental Protection

ABSTRACT The thermal oxidation degradation and kinetic behavior of four waste shell powders: Hyriopsis cumingii, abalone, scallop, and clam were investigated. The thermal oxidation degradation process was elucidated using thermogravimetric analysis, X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and the Coats-Redfern method. This process typically occurs in four stages, with the decomposition of CaCO₃ (Stage III) being pivotal. Notably, clam and scallop powders exhibited the highest CaO yields of approximately 55.1% and 55.0%, respectively. Although abalone powder had a lower yield of 50.2%, it demonstrated the lowest activation energy of 118.08 kJ/mol in Stage III, suggesting potential energy and cost savings during CaO conversion. High-temperature calcination altered the chemical composition and microstructure of the shell powders, resulting in rough and porous CaO surfaces conducive to heavy metal ion and pollutant adsorption. The research provides a theoretical framework and experimental validation for the sustainable utilization of calcined shell powders, fostering efficient shell resource management and environmental protection.

Kinetic Analysis of Proton-Coupled Electron Transfer at an Electrode-Immobilized Complex

Kinetic Analysis of Proton-Coupled Electron Transfer at an Electrode-Immobilized Complex

Innovative Strategies for Tannery Wastewater Remediation with Sequential batch reactor and phycoremediation

&lt;p style="line-height:150%;text-align:justify;"&gt;&lt;span style="font-family:&amp;quot;Times New Roman&amp;quot;,serif;font-size:12.0pt;" lang="EN-IN"&gt;This research assessed the performance of combining Sequential Batch Reactor (SBR) and phycoremediation method used for tanning effluent. The SBR system obtained high removal efficiencies with Chemical Oxygen Demand (COD)&amp;nbsp; is reduced by&amp;nbsp; 85%, Biological Oxygen Demand (BOD) is reduced&amp;nbsp; by 80% as well as ammonia by more than 75%. Chromium and lead were dropped by 65% and 60% correspondingly after treatment. Following SBR process, inclusion of Chlorella vulgaris in the phycoremediation stage further improves the removal of pollutants achieving 95% COD and 92% BOD reductions. Heavy metal removal was enhanced with chromium and lead by reducing 85% each. Kinetic analysis indicated that ammonia and COD removal followed first-order kinetics with high model fit (R2=0.93 for COD; R2=0.91 for ammonia). Heavy metal removal using Chlorella vulgaris also conformed to first-order kinetics. A temporary increase in ammonia levels was observed due to nitrification inhibition during periods of high organic loads in the wastewater discharged from tanneries into rivers or lakes without treatment facilities such as oxidation ditches or stabilization ponds used in some cases. Finally, it can be concluded that an integrated SBR phycoremediation process shows very good potentialities with respect to good performances in treating wastewater efficiently.&lt;/span&gt;&lt;/p&gt;

CRISPR-AsCas12f1 couples out-of-protospacer DNA unwinding with exonuclease activity in the sequential target cleavage.

Type V-F CRISPR-Cas12f is a group of hypercompact RNA-guided nucleases that present a versatile in vivo delivery platform for gene therapy. Upon target recognition, Acidibacillus sulfuroxidans Cas12f (AsCas12f1) distinctively engenders three DNA break sites, two of which are located outside the protospacer. Combining ensemble and single-molecule approaches, we elucidate the molecular details underlying AsCas12f1-mediated DNA cleavages. We find that following the protospacer DNA unwinding and non-target strand (NTS) DNA nicking, AsCas12f1 surprisingly carries out bidirectional exonucleolytic cleavage from the nick. Subsequently, DNA unwinding is extended to the out-of-protospacer region, and AsCas12f1 gradually digests the unwound DNA beyond the protospacer. Eventually, the single endonucleolytic target-strand DNA cleavage at 3 nt downstream of the protospacer readily dissociates the ternary AsCas12f1-sgRNA-DNA complex from the protospacer adjacent motif-distal end, leaving a staggered double-strand DNA break. The coupling between the unwinding and cleavage of both protospacer and out-of-protospacer DNA is promoted by Mg2+. Kinetic analysis on the engineered AsCas12f1-v5.1 variant identifies the only accelerated step of the protospacer NTS DNA trimming within the sequential DNA cleavage. Our findings provide a dynamic view of AsCas12f1 catalyzing DNA unwinding-coupled nucleolytic cleavage and help with practical improvements of Cas12f-based genome editing tools.

Abstract 4133040: Cardiac Favored Transcription of the Exogenous Gene in Mice after A Single Systemic Delivery of AAV9-cBIN1

Introduction: Heart failure (HF) is associated with high mortality and morbidity, and there are limited therapeutic options available to improve cardiac muscle function. Recent studies suggest that the impairment of cardiomyocyte T-tubule microdomains is a key factor in HF pathophysiology. AAV9-cBIN1 gene therapy effectively addresses this impairment. However, the kinetics and biodistribution of AAV9-cBIN1 have not been explored, limiting the knowledge of the transcription efficiency and organ specificity of cBIN1 gene therapy when delivered systemically. Aim: This study aims to elucidate the kinetics and biodistribution of AAV9-cBIN1 in a murine model. Method: Adult male C57BL/6J mice (n=20) were administered a single retro-orbital injection of AAV9-CMV-cBIN1-V5 at a dose (2x10^12 vg/kg) known to effectively transduce the majority of cardiomyocytes. Mice were sacrificed at pre-determined time points: prior to injection (Day 0, n=2) and post-injection at Days 3, 7, 14, 28, 56, and 84 (n=3/group). Tissues were harvested from the heart, lung, liver, kidney, skeletal muscle, and spleen. Genomic DNA was extracted and analyzed using qPCR to determine vector genome (vg) copies. For transcriptional analysis of the AAV9-transduced exogenous gene, mRNA was extracted and converted to cDNA for qRT-PCR quantification of cBin1-V5 , normalized to the housekeeping gene Hprt1 . Results: All mice survived to their designated sacrifice times. Kinetic analysis demonstrated a time-dependent expression of the exogenous cBin1-V5 gene, with peak expression observed at 4 weeks in both the heart and liver, with expression declining in the liver after this peak (Figure 1A). Genomic DNA analysis showed a gradual increase and plateau of viral genome distribution in the heart between 2-4 weeks, while in the liver, distribution peaked sharply between Days 3-7 and then decreased. When correcting the gene transcription of cBin1-V5 (ΔCq of V5/Hprt1 ) for vector DNA vg copies in the tissue, the transcription efficiency in the heart was higher than in the liver (Figure 1B). Outside of the liver and heart, cBin1-V5 mRNA expression was undetectable in all other tissues by Day 56. Conclusion: In adult male mice, a single systemic administration of AAV9-cBIN1 results in robust transduction and higher transcription efficiency in the heart compared to the liver. AAV9-cBIN1 holds promise for targeted gene therapy in cardiac tissues, with minimal off-target expression in other organs.

Accelerated weathering of construction‐grade limestone for CO2 absorption

AbstractAccelerated weathering of limestone (AWL) process efficiently captures CO2 from point source emissions. However, despite achieving an outstanding capture efficiency of 73.51 %, lab‐grade (LG) limestone with 99.90 % CaCO3 as an absorbent is costly ($2757.70/t), making commercialization of AWL impractical. This work delves into the viability of utilizing construction‐grade (CG) limestone (93.26% purity) for the AWL process facilitated by potable water in an absorption tower for post‐combustion capture. The result shows that CG limestone achieves comparable CO2 capture efficiency of 8.0–74.68% and bicarbonate (Ca(HCO3)2) concentration of 0.63–3.10 mM compared with LG limestone. However, LG limestone has 0.29 mol CO2/mol CaCO3 higher CO2 absorption capacity and a faster absorption rate than CG limestone, indicating a somewhat better CO2 capture performance. Nevertheless, CG limestone offered a more cost‐effective alternative, with a $2735.24 lower cost per ton of CaCO3 and a $2651.63 per ton CO2 lower CO2 capturing cost at the highest carbon capture efficiency (HCCE) condition compared to LG limestone. The kinetic analysis shows that the forward reactions in the AWL process are significantly faster at elevated CO2 concentration, with the mass transfer coefficient affirming that CO2 dissolves faster than CaCO3, in line with prior research. Thus, this work validates that CG limestone‐based AWL achieves comparable CO2 capture performance to that of LG limestone, offering a cost‐efficient alternative. © 2024 Society of Chemical Industry and John Wiley &amp; Sons, Ltd.

The kinetics of moisture sorption by hair.

The rate process of moisture sorption by human hair has been analysed in order to hints for helping deepen knowledge on the hair structure and to explain the behaviour of hair in response to moisture. The isotherms of moisture sorption by hair were recorded, via dynamic vapour sorption (DVS), for untreated (virgin) and treated (heat-shaped and bleached) hair, as well as for separated cuticle and cortex. By considering that, during moisture uptake, the hair fibres also swell, it is possible to introduce a time-dependent rate constant for describing the kinetics of the moisture sorption. This model allows for clearly separating the moisture sorption processes occurring in Cuticle and in Cortex and for proposing a role of chain entanglement in the two main compartments of the fibre. It may also provide some hints on the structural changes occurring in the fibre after different cosmetic treatments. The influence of the weight of the sample on the kinetics of the sorption process has also been noted and quantified. The analysis pointed to a transition occurring at around 30% relative humidity, assigned to the opening of the hair inner structure, and accommodation of more water molecules. This allowed for an estimate of the value of the activation energy of the water molecules reacting with the active sites, which was found to be in good agreement with results published in the literature. The analysis of the kinetics of moisture sorption by hair was shown not only to provide information on the chain entanglement inside the fibre and the effect of cosmetic treatments but also to demonstrate and quantify the influence of fibre density on the sorption process. It is thus suggested that, along with examination of the hysteresis, the analysis of sorption kinetics helps reveal a more complete picture of hair moisture management.

Facile Synthesis of Polypyrrole-Decorated RGO-CuS Nanocomposite for Efficient Nickel Removal from Wastewater

Efficient wastewater treatment, particularly the removal of heavy metal ions, remains a challenging priority in environmental remediation. This study introduces a novel sandwich-structured nanocomposite, RGO-CuS-PPy, composed of reduced graphene oxide (RGO), copper sulfide (CuS), and polypyrrole (PPy), synthesized via a straightforward hydrothermal method. The unique combination of RGO, CuS, and PPy offers enhanced adsorption capacity for Ni(II) ions due to RGO’s high surface area and CuS’s active binding sites, supported by PPy’s structural stability contributions. This study is among the first to explore this specific nanocomposite architecture for Ni(II) removal, achieving an adsorption capacity of 166.67 mg/g and a high removal efficiency of 94.9% within 210 min for 55 mg/L of Ni(II) concentration at pH 6 and adsorbent dose of 3 mg/15 mL. The kinetic analysis shows the best fitted time-dependent experimental data with the pseudo-second-order model, indicating chemisorption. Isotherm studies confirmed the Langmuir model as the best fit, yielding a high monolayer adsorption capacity of 166.67 mg/g. Thermodynamic analysis shows the adsorption process was endothermic (ΔH° = 80.23 kJ/mol) and spontaneous (ΔG° ranging from −6.985 to −14.399 kJ/mol). Additionally, reusability tests using 0.1 M HCl for desorption demonstrated good reusability, emphasizing the RGO-CuS-PPy nanocomposite’s potential as a sustainable adsorbent for Ni(II) removal in wastewater treatment applications.