The performance of modified corncob (MC) as an adsorbent for waste diesel engine oil purification was further evaluated through systematic optimization of key operational parameters: adsorbent dosage, temperature, and contact time. These factors were investigated to determine their influence on the removal efficiency of wear metals—Fe, Al, and Cu—and to establish the most effective conditions for practical application. Experiments were conducted under controlled settings using WLO samples with 40,000 km, 60,000 km, and 80,000 km mileage, maintaining consistent stirring speed (1000 rpm) and adsorption volume.
Adsorbent dosage was tested at concentrations ranging from 0.1% to 3% (w/w). Results showed that increasing the MC dosage led to a progressive improvement in metal removal rates, reaching near-plateau levels at 2%. At this concentration, Fe removal reached 92%, Al 87%, and Cu 91% for the 80,000 km oil sample. Further increases beyond 2% yielded minimal gains, indicating saturation of active sites. This suggests that 2% is the optimal dosage for maximizing efficiency while minimizing material usage, making it economically viable for industrial-scale applications.
Temperature played a critical role in enhancing mass transfer and molecular diffusion. Experiments were performed between 50°C and 100°C. The lowest wear metal concentrations were achieved at 90°C, where viscosity of the lubricating oil decreased significantly, improving fluidity and enabling faster movement of contaminants toward adsorption sites. At this temperature, the adsorption rate for Fe increased by 35% compared to 50°C, and equilibrium was attained more rapidly. The enhanced thermal energy also promoted desorption of weakly bound molecules, allowing stronger interactions with functional groups on MC.Cytokeratin 17 Antibody manufacturer However, temperatures above 90°C did not yield additional benefits and risked degrading the oil or altering its chemical structure, thus confirming 90°C as the optimal operating temperature.
Contact time was analyzed over intervals from 5 to 120 minutes. The adsorption process exhibited rapid kinetics, with nearly 80% of the maximum removal capacity achieved within the first 10 minutes.PRLR Antibody Autophagy For Fe, Al, and Cu, equilibrium was essentially reached by 60 minutes, after which no significant change occurred.PMID:35028273 This indicates that MC possesses high affinity and fast access to active sites, likely due to the improved porosity and surface area resulting from modification. The short equilibrium time supports potential use in real-time filtration systems, such as those integrated into engine oil filters.
Moreover, the stability and reusability of MC were assessed through multiple regeneration cycles. After each cycle, MC was regenerated using ethanol washing followed by drying at 60°C. The adsorption capacity retained over 85% of its initial performance after five cycles, demonstrating good durability and sustainability. This feature is crucial for reducing operational costs and waste generation in long-term applications.
In summary, the optimal adsorption conditions for MC are 2% adsorbent dosage, 90°C temperature, and 60 minutes contact time. Under these conditions, MC achieves superior removal of both metallic and organic contaminants in WLO, including a substantial reduction in total acid number (TAN), which is essential for preventing engine corrosion and degradation. The combination of high efficiency, rapid kinetics, low cost, and environmental compatibility positions modified corncob as a promising candidate for next-generation oil purification technologies. Its successful implementation could revolutionize waste oil recycling practices, supporting circular economy principles in the automotive and industrial sectors.MedChemExpress (MCE) offers a wide range of high-quality research chemicals and biochemicals (novel life-science reagents, reference compounds and natural compounds) for scientific use. We have professionally experienced and friendly staff to meet your needs. We are a competent and trustworthy partner for your research and scientific projects.Related websites: https://www.medchemexpress.com
