Submissões Recentes
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Application of advanced oxidation processes for remediation of rubber industry wastewater
2026 - ULLAH, ZAFRAN; TIAN, ZHEN-YU; JOSEPH, COLLIN G.; GUILHEN, SABINE N.; TEO, SIOW H.; GANSAU, JUALANG A.; SARBATLY, ROSALAM; ALIAS, KARTINI; SUBHRAMANIYUN, PRETIBAA; KHAN, MUHAMMAD N.; IQBAL, MUHAMMAD S.
Rubber is an industrial material valued worldwide for its remarkable elasticity and versatility. It has become an essential material among the several various sectors, contributing to technological progress and improving the quality of everyday life. In the twenty-first century, increasing global awareness over rubber pollution has highlighted the significant attention towards the ecological footprint and sustainability challenges associated with rubber materials. The manufacturing of rubber is known to produce effluents that are difficult to treat with existing technologies. These effluents are known to have a high chemical oxygen demand (COD) and biological oxygen demand (BOD) alongside organic toxic pollutants. However, the new advanced oxidation processes (AOPs) for treating such wastewater have shown promise alongside AOPs that produce high amounts of hydroxyl radicals. This paper analyzes other prominent techniques such as Fenton and photo-Fenton, photocatalysis, ozonation, and electrochemical oxidation, aimed at treating rubber industry effluents. These techniques are found to be highly effective against resistant pollutants and aid in increasing biodegradation efficiency. The Fenton processes, alongside AOP technologies, pose some operational challenges and are not advanced enough to have cost-effective and efficient solutions. The combination of AOPs with biological processes and other recent studies have been shown to be effective, but more research needs to be done on their economic viability. We have also emphasized the important role of hybrid synergistic systems and AI in improving the effectiveness of AOPs for achieving better waste management practices in the rubber industry.
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Integrated twin-screw extrusion and organosolv pretreatment efficiently enhances cellulose-to-glucose conversion and lignin recovery from corn cobs
2026 - JOSE, ALVARO H. M.; RODRIGUES, BRUNA G.; MOURA, ESPERIDIANA A. B.; MOTTA, JOAO V. S.; MOREIRA, RENATA; RODRIGUES, RITA C. L. B.
Efficient conversion of lignocellulosic biomass into bioproducts depends on optimized pretreatment strategies that enhance the accessibility of structural macromolecules. However, individual methods often face limitations regarding cellulose-to-glucose conversion and lignin recovery. This study evaluated an integrated approach combining twin-screw extrusion, organosolv fractionation, and enzymatic hydrolysis using corn cobs as feedstock. A factorial design applied to the extrusion process identified optimal conditions (144 °C, 11 rpm), resulting in a cellulose-to-glucose conversion of 92.6 wt% after enzymatic hydrolysis. In the subsequent organosolv step, treatment time was the most influential factor for improving cellulose digestibility. A second factorial design identified optimal conditions (60 min, 20.1 wt% solids), yielding the highest glucose conversion (93.0 ± 1.2 wt%) and enabling recovery of 45.4% of the solubilized lignin. Additionally, increasing solids loading from 10 to 15 wt% during enzymatic hydrolysis improved glucose productivity by 23.7%. These findings demonstrate that integrating twin-screw extrusion and organosolv pretreatment effectively enhances sustainable valorization of corn cobs.
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Luminescent and dosimetric properties of CaSO4:RE,Mn (RE = Dy, Tb, Tm, Yb, Eu, Ce) phosphors synthesized by the slow evaporation method
2026 - SILVA, ANDERSON M. B.; JUNOT, DANILO O.; TRINDADE, NEILO M.; SOUZA, DIVANIZIA N.; CALDAS, LINDA V. E.
This study investigates the luminescent and dosimetric properties of CaSO4:Dy,Mn, CaSO4:Tb,Mn, CaSO4:Tm,Mn, CaSO4:Yb,Mn, CaSO4:Eu,Mn and CaSO4:Ce,Mn composites synthesized via the slow evaporation route. Structural and compositional characterization was performed using X-ray diffraction (XRD) and energy-dispersive spectroscopy (EDS). The dosimetric performance of the materials was evaluated using Teflon-based pellets through thermoluminescence (TL) glow curve measurements. Additionally, Continuous Wave Optically Stimulated Luminescence (CW-OSL) measurements were conducted to assess their optical stimulation behavior. The TL emission spectra revealed characteristic transitions associated with both RE3+ and Mn2+ ions, with emission features strongly dependent on the specific dopant. The TL glow curves exhibited well-defined peaks in the UV and visible regions, with Tm,Mn, Dy,Mn and Tb,Mn codoped samples showing enhanced emissions at higher temperatures, a desirable feature for dosimetric applications. CW-OSL measurements demonstrated intense luminescence responses, particularly for the CaSO4:Tm,Mn and CaSO4:Ce,Mn compositions. A comprehensive dosimetric evaluation was conducted, including reproducibility, linearity and signal fading. Among the studied samples, CaSO4:Tm,Mn exhibited the most stable TL response, while CaSO4:Dy,Mn showed the superior OSL signal stability. Overall, the results demonstrate that these newly developed CaSO4-based RE,Mn composites possess excellent dosimetric characteristics, highlighting their strong potential as TL/OSL radiation detectors.
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Evaluation of electrochemical regeneration of antibiotic-loaded clay in a single-reactor process
2026 - ANTONELLI, RAISSA; GOIS, ANTONIA R. dos S.; MALPASS, GEOFFROY R. P.; BORRELY, SUELI I.; TEIXEIRA, ANTONIO C. S. C.
This study investigated the in situ electrochemical regeneration of a clay adsorbent loaded with sulfamethoxazole (SMX) using two systems (NaCl/DSA and Na2SO4/BDD), aiming to understand the regeneration process and evaluate the quality of the generated electrolyte solution. The NaCl/DSA system exhibited higher regeneration efficiency (RE: 135–97 %) compared to Na2SO4/BDD (RE: 101–51 %), highlighting the role of active chlorine species in SMX degradation. During regeneration, SMX was not detected in the solution, being degraded into transformation products, or mineralized. The presence of traces of hydrocarbons and the increase in the total organic carbon content in the electrolytic solution suggest partial oxidation of the surfactant present in the clay formulation, possibly generating new active sites and enhancing adsorption capacity (RE > 100 %). However, extended regeneration times appear to promote significant loss of adsorbent integrity. The compounds detected in the solution resulting from the Na2SO4/BDD system indicate more pronounced degradation of the clay matrix, which may have influenced its lower regenerative efficiency. Although the NaCl/DSA system demonstrated greater efficiency, its corresponding electrolyte solution exhibited increased toxicity toward Lactuca sativa seedlings. In contrast, acute toxicity tests using Aliivibrio fischeri indicated that the produced electrolytic solutions did not have any inhibitory effects. Furthermore, photolysis treatment lowered phytoxicity and improved environmental compatibility. Finally, characterization analyses demonstrated preservation of the structural integrity of the clay against the applied processes.