This research explores the potential of microwave-synthesized MoS2-graphene nanohybrid as additives to enhance the tribological properties of diesel-based engine oil. The synthesis method offers significant advantages, reducing both synthesis time and energy consumption by 90-98% compared to conventional approaches. The synthesized nanohybrids are characterized through FESEM, EDX, XRD, and Raman spectroscopy to understand their morphology and functional group interactions. These nanohybrids are incorporated into 20W40 engine oil following synthesis, and a comprehensive assessment of their properties is conducted. This evaluation covers critical parameters like viscosity index, stability, volatility, as well as tribological properties, oxidation resistance, and thermal conductivity of the oil-nanohybrid system. Results demonstrate that adding just 0.05 wt% of MoS2-graphene nanohybrid leads to a remarkable 58.82% reduction in friction coefficient and a significant 36.26% decrease in the average wear scar diameter. Additionally, oxidation resistance improves by 19.21%, while thermal conductivity increases notably by 19.83% (at 100 °C). The study demonstrates the synergistic effects of these nanohybrids in reducing friction and wear, enhancing oxidation resistance, and improving thermal conductivity. In conclusion, this research highlights the potential of microwave-synthesized MoS2-graphene nanohybrid as promising tribological additives for diesel engine oils. Their successful integration could significantly enhance the performance and durability of critical mechanical components in diesel engines, representing a significant advancement in lubrication technology.
In this study, MoS2-hBN hybrid nanoparticles were synthesized using an advanced microwave platform for new nanolubricant formulations. The synthesized nanoparticles were characterized by field-emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, and Raman spectroscopy. The hybrid nanoparticles were then introduced into a 20W40 diesel-based engine oil to produce a nanolubricant. The physical and chemical properties of the nanolubricant were investigated, including the viscosity index, stability, volatility, tribological properties, oxidation properties, and thermal conductivity. The results showed that the inclusion of 0.05 wt% MoS2-hBN hybrid nanoparticles in the oil significantly reduced the coefficient of friction and wear scar diameter by 68.48% and 35.54%, respectively. Moreover, it exhibited substantial oxidation and thermal conductivity improvement of 38.76% and 28.30%, respectively, at 100 °C. These findings demonstrate the potential of MoS2-hBN hybrid nanoparticles as an effective additive to enhance the properties of nanolubricant significantly. Furthermore, this study offers valuable insights into the underlying mechanisms responsible for the observed enhancements. The promising outcomes of this investigation contribute to the advancement of nanotechnology-based lubricants, showcasing their potential for improving engine efficiency and prolonging the lifespan of machinery.
This study presents the adsorption of methylene blue (MB) dye using latex char derived from pyrolysis of latex gloves. The adsorption process was investigated systematically using Response Surface Methodology (RSM) with a Central Composite Design (CCD). The effects of four key variables, namely pH, time, temperature, and adsorbent dosage, were studied using a factorial design enriched with center points and axial points. Experimental data were analyzed using a second-order polynomial regression model to construct a response surface model, which elucidated the relationship between the variables and MB removal efficiency. The study found that the char obtained at 800 °C exhibited the highest adsorption capacity due to its increased carbonization, expanded surface area, and diverse pore structure. Analysis of Variance (ANOVA) confirmed the significance of the quadratic model, with remarkable agreement between predicted and experimental outcomes. Diagnostic plots validated the model's reliability, while 3D contour graphs illustrated the combined effects of variables on MB removal efficiency. Optimization using DoE software identified optimal conditions resulting in a 99% removal efficiency, which closely matched experimental results. Additionally, adsorption isotherms revealed that the Freundlich model best described the adsorption behavior, indicating heterogeneous surface adsorption with multilayer adsorption. This comprehensive study provides valuable insights into the adsorption process of MB dye using latex char, with implications for wastewater treatment and environmental remediation.
This study investigates the potential of spent coffee ground biochar (SCGB) as a sustainable and cost-effective adsorbent for the removal of methylene blue (MB), a hazardous dye commonly used in the textile and printing industries. A response surface methodology (RSM) approach with central composite design (CCD) was employed to systematically investigate the effects of key process parameters, including adsorbent dosage, solution pH, contact time and temperature, on MB removal efficiency. The analysis revealed that adsorbent dosage and temperature as critical factors influencing MB removal, with a linear model providing a strong correlation. Optimal conditions for MB removal were determined to be 0.99 g of SCGB, 30 min of contact time, 30 °C temperature, and a solution pH of 7. Under these conditions, MB removal reached 99.99%, with a desirability of 1.000. The experimental results closely matched the predicted values, differing by only 0.02%, thus validating the accuracy of the model. Kinetic studies indicated a rapid adsorption process, well-described by both pseudo-first and pseudo-second order models. Isotherm analysis confirmed the applicability of the Freundlich model, suggesting favorable adsorption with increasing MB concentration. The high adsorption capacity of SCGB is attributed to its carbonaceous and porous structure, highlighting its potential as an effective adsorbent for dye removal in wastewater treatment applications.