FTIR Analysis Research Articles

Transforming waste into wealth in sustainable shrimp aquaculture: Effective phosphate removal and recovery using shrimp shell-derived adsorbents

The growing global demand for shrimp has driven the intensification of shrimp aquaculture, leading to significant environmental challenges due to nutrient-rich wastewater and solid waste. This study developed shrimp shell-derived adsorbents (SSs) by pyrolysis and calcium hydroxide (Ca(OH)2) activation to remove phosphate (PO43−) from aqueous solutions. Ca(OH)2 activated adsorbent achieved higher PO43− removal than adsorbent obtained at higher pyrolysis temperature, with adsorption capacities up to 381.24 mg/g of PO43− at 20 °C. The primary mechanism driving PO43− removal was chemical precipitation between Ca and PO43−. SSs were found to release Ca2+ from hydroxylellestadite (HDL), Ca(OH)2, and calcium carbonate (Ca(CO)3). Additionally, ligand exchange of PO43− by Ca(CO)3 and π-π interactions from aromatic rings further enhanced the PO43− adsorption. SEM-EDS showed PO43− dispersed on the SSs surface. XPS revealed that Ca-O bond was shifted to Ca-P bond with a higher binding energy and a new π-π interaction peak appeared at 293.60 eV. FTIR confirmed ligand exchange between PO43− and CO32−, with the 1400 cm−1 band disappearing and a new 870 cm−1 band appearing. The XRD, FTIR, and XPS analyses confirmed the formation of various calcium-phosphate (Ca-P) groups, including calcium apatite (Ca-apatite), monocalcium phosphate (Ca(H2PO4)2), and dicalcium phosphate (CaHPO4), on the saturated SSs. Specifically, all XPS spectra of Ca-O moved to higher binding energy, reflecting Ca-P linkages. This study provides a sustainable alternative for handling shrimp shell waste and suggests a promising approach for PO43− recovery, thereby contributing to a circular system in shrimp aquaculture.

Single-use commercial bio-based plastics under environmental degradation conditions: Is their biodegradability and compostability a fact?

Evaluating compostability is increasingly essential for proving commercial bio-based cutlery or packaging since these materials must biodegrade under controlled conditions quickly. Utensils for eating represent Mexico's most popular consumer single-use materials, and Mexican regulations based on biodegradation or compostability are still vague and lack scientific evaluations. This study analyzed three bio-based polymeric materials (bags, dishes, and forks) from commercial brands following Mexican regulations and using various analytical techniques to verify their biodegradability and compostability. First, weight loss measurements, stress-strain tests, and topographic imaging were applied for preliminary observations at the macro scale up to 90 days of compostability. Besides, spectroscopy, microscopy, and thermal techniques indicate changes and behavior of the bio-based materials depending on the composition. The results suggest that bags exhibited the highest decomposition rate (80 %) compared to dishes and forks. Similarly, mechanical resistance indicates a reduction of 62 % for bags, 30 % for dishes, and almost none for forks. Texture image analysis revealed that the complexity and roughness of the materials increased over time, correlating with the physical changes observed. These results indicate minimal surface topography changes and higher stiffness for dishes and forks, indicating low biodegradability. SEM images supported these findings, showing surface degradation in bags and dishes but not in forks. FTIR and XRD analyses confirmed the presence of polyamide (bags) and polypropylene (dishes and forks). These results reduce biodegradation and differ from the claims made by manufacturers. The thermal analysis found similar results, indicating that the materials' thermal stability decreased after degradation, which is related to lower biodegradability and compostability. Overall, the study concluded only bags meet the criteria for compostability in national regulations. However, dishes and forks made of petroleum-derived polymers have higher resistance to natural and microbial degradation.

Nanopriming with phytofabricated selenium nanoparticles alleviates arsenite-induced oxidative stress in Spinacia oleracea L.

Arsenic (As) contamination of agricultural soil has become a major concern due to its adverse effects on plant growth and human health. Selenium nanoparticles (SeNPs), a novel selenium (Se) source, are characterised by their exceptional biocompatibility, degradability, and bioactivities. In the present study, SeNPs were biogenically synthesised and further characterised using UV-visible spectroscopy, XRD, FTIR, and TEM analysis. Different concentrations of the synthesised SeNPs were used to treat Spinacia oleracea L. (spinach) seeds to determine their impact on growth profile, gas exchange, photosynthetic pigments, oxidative stress, and antioxidant enzyme status upon arsenite (AsIII) treatment. The findings revealed that SeNP supplementation at a concentration of 100µM (SeNPs100) led to a significant reduction in As accumulation by twofold in roots and 1.5-fold in leaves when compared to plants exposed to AsIII100 (µM) alone. Interestingly, the photosynthetic efficiency was also remarkably enhanced upon SeNPs100 treatment, associated with increased activities of the defence enzymes (ascorbate peroxidase, catalase, and glutathione peroxidase) in the AsIII + SeNP-exposed spinach plants as compared to AsIII treatment alone. Overall, the present study highlights the potential of biogenic SeNP supplementation in promoting plant growth and mitigating As toxicity in spinach under AsIII stress. This study could have significant implications for the use of SeNPs as a nanofertiliser in regions grappling with As-contaminated soils for sustainable agriculture and human health.

Construction of visible-light-induced Fe2O3/g-C3N4 nanocomposites for the enhanced degradation of organic dyes: Optimization of operative parameters

This research aims to develop the highly promising Fe2O3/g-C3N4 photocatalyst through hydrothermal techniques to cope with the elevated amounts of bromophenol blue (BPB) dye in wastewater. The morphological studies were carried out by SEM analysis, while the crystallinity, structural behavior, and oxidation states of the prepared materials were determined by XRD, FTIR, and XPS analysis. The hydrodynamic size, surface area, and magnetic characteristics of the constructed materials were assessed through DLS, BET, and VSM analysis. The effectivity of the synthesized Fe2O3 and Fe2O3/g-C3N4-30 photocatalysts was appraised by the abatement of BPB under visible light radiation for 48 min. The results have shown an excellent degradation efficacy of Fe2O3/g-C3N4-30 photocatalyst with 98.39 % of BPB removal and a rate constant of 0.0757 min−1, which was much higher than Fe2O3 photocatalyst with 79.64 % of removal and a rate constant of 0.0335 min−1 under optimum conditions. The enhancement in degradation efficiency of the Fe2O3/g-C3N4-30 was due to the large surface area of Fe2O3/g-C3N4-30 (106.94 m2/g) as a result of g-C3N4 inclusion in the material, while the pure Fe2O3 unveiled a surface area of 89.67 m2/g. The impact of different reaction parameters on BPB degradation was also investigated, while the contribution of free radicals was corroborated through radical trapping experiments. The Fe2O3/g-C3N4-30 exhibited tremendous stability for repeated applications, with a loss of 8.03 % in efficiency after five consecutive experiments because of its easy magnetic separation. The experimental results have shown that synthesized Fe2O3/g-C3N4-30 photocatalysts could be used for the effective degradation of BPB from wastewater.

Comparative Study of Interfacial and Conventional Techniques for Nanosilica Incorporation in Natural Rubber Latex-Based Composites with Varied TEOS Content

This study investigates the preparation of natural rubber latex (NRL) composites with varying nanosilica contents of 5, 15, 30, and 45 phr, using both interfacial and conventional mixing techniques. Analysis focused on viscosity, plasticity, morphology, and FTIR spectra to evaluate the impact of these methods on composite properties. The interfacial techniquemaintained lower viscosity values, indicating better latex stability, and achieved higher silica yields and conversion rates (94 - 99%) at elevated TEOS contents. Plasticity analysis revealed that the interfacial method produced more uniform and stable plasticity values, suggesting improved resistance to oxidation and enhanced mechanical properties. SEM and FTIR analyses confirmed superior dispersion with the interfacial technique, especially at higher silica contents. These findings highlight the efficacy of the interfacial technique in optimizing the properties of NRL composites, making it a promising approach for advanced material applications. HIGHLIGHTS Analysis of interfacial and conventional mixing techniques reveals their impact on NRL composite properties, demonstrating the interfacial method's superior stability, silica dispersion, and enhanced mechanical properties. The interfacial method maintains lower, stable viscosity, prevents latex destabilization, achieves higher silica yields, and ensures economic and sustainable production of high-quality composites. SEM and FTIR analyses confirm better silica dispersion and morphology with the interfacial method, enhancing composite performance, durability, and informing industrial applications and future research directions. GRAPHICAL ABSTRACT

Limitations and characteristics of converted industrial acrylic sheet into an in vitro platform using CO2 laser

The recent US FDA Modernization Act 2.0 has intensified interest in microfluidic-based in vitro systems for preclinical research. However, the high costs of conventional microfabrication methods and commercial devices present significant barriers, particularly in developing countries. This study addresses these challenges by exploring the use of industrial-grade acrylic sheets and a conventional CO2 laser for cost-effective microfabrication. The research investigates the effects of laser parameters—specifically nozzle speed and power—on the dimensions and quality of microchannels, surface roughness, and bonding strength. Results indicate that increased nozzle speed reduces kerf width and enhances microchannel quality, whereas high laser power (∼52 watts) induces bubbling at the edges. A simple acetone and ethanol mixture was found to provide optimal bonding strength without altering the acrylic’s molecular structure. UV spectrophotometry revealed minimal changes (∼6 %) in visible light transmittance due to bonding conditions, while FTIR analysis showed no residuals that could potentially cause cytotoxicity. Despite variations in surface roughness resulting from the etching process, cell viability remained unaffected. The surfaces supported effective cell culture for lung (A549), neuron (SH-SY5Y), and liver (HepG2) cell lines. This approach presents a practical and cost-effective solution for developing in vitro platforms, making it an accessible option for research and academic applications.

Selective adsorption of cationic dye by κ-carrageenan-potato starch bio-hydrogel: Kinetics, isotherm, and thermodynamic studies

An eco-friendly κ-carrageenan/potato starch bio-hydrogel is designed for the efficient removal of methylene blue (MB) dye from water. The incorporation of potato starch was successfully confirmed through XRD, FT-IR, and SEM analysis, while TGA highlighted the hydrogel's thermal stability. Batch adsorption experiments demonstrated excellent MB removal efficiency, with a maximum adsorption capacity of 116.1 mg/g under optimal conditions (initial dye concentration: 100 mg/L, contact time: 180 min, temperature: 20 °C, adsorbent dosage: 1.6 g/L, and pH: 11). FT-IR analysis indicated that electrostatic interactions and hydrogen bonding primarily govern the adsorption process. The adsorption followed pseudo-second-order kinetics and fitted well with the Langmuir isotherm model. Thermodynamic studies revealed that the adsorption was exothermic and spontaneous. A key feature of this bio hydrogel is its selective affinity for the cationic dye MB, in a mixture with Acid Orange (AO) and other cationic dyes (Rhodamine B (Rh B) and crystal violet (CV)). The adsorbent also demonstrated impressive reusability, maintaining 93 % of its efficiency after five cycles, highlighting its potential for sustainable and cost-effective water treatment.

Zn-Al layered double hydroxide supported on waste cow dung-derived biochar as a highly efficient adsorbent for anionic dye removal from contaminated water.

In this study, Zn-Al-SO42- LDH-functionalized biochar was fabricated using the co-precipitation method. The biochar was synthesized from waste cow dung using a low-temperature pyrolysis process (300 °C). The materials were fully characterized by TGA, FTIR, EDS, SEM, and XRD analysis. Then, a comparative study was performed to investigate the adsorption capacity of the materials against an anionic dye (i.e., methyl orange (MO)). The LDH-functionalized biochar demonstrated high adsorption capacity (400 mg/g in 120 min, at pH 5) compared to the raw biochar (212 mg/g in 120 min, at pH 5). The effect of various adsorption parameters (e.g., pH of the dye solution, temperature, initial concentration, adsorbent dosage, and contact time) was investigated. The adsorption of MO on LDH-functionalized biochar followed the Freundlich isotherm and pseudo-second-order kinetics, while the raw biochar followed the Langmuir isotherm and pseudo-second-order kinetics. The thermodynamic data indicated the endothermic nature of adsorption and an increase in the degree of randomness during adsorption. The enhanced adsorption capacity of the Zn-Al LDH-functionalized char was attributed to the synergistic effect of the surface adsorption into the porous biochar matrix, interlayer adsorption, and ion exchange capacity of the LDHs. Therefore, modification of waste cow dung-derived biochar with Zn-Al LDH can be a promising approach to fabricate a highly efficient adsorbent for toxic dyes from wastewater.

Biosynthesis of Iron Oxide Nanoparticles by Marine Streptomyces sp. SMGL39 with Antibiofilm Activity: In Vitro and In Silico Study

One of the major global health threats in the present era is antibiotic resistance. Biosynthesized iron oxide nanoparticles (FeNPs) can combat microbial infections and can be synthesized without harmful chemicals. In the present investigation, 16S rRNA gene sequencing was used to discover Streptomyces sp. SMGL39, an actinomycete isolate utilized to reduce ferrous sulfate heptahydrate (FeSO4.7H2O) to biosynthesize FeNPs, which were then characterized using UV–Vis, XRD, FTIR, and TEM analyses. Furthermore, in our current study, the biosynthesized FeNPs were tested for antimicrobial and antibiofilm characteristics against different Gram-negative, Gram-positive, and fungal strains. Additionally, our work examines the biosynthesized FeNPs’ molecular docking and binding affinity to key enzymes, which contributed to bacterial infection cooperation via quorum sensing (QS) processes. A bright yellow to dark brown color shift indicated the production of FeNPs, which have polydispersed forms with particle sizes ranging from 80 to 180 nm and UV absorbance ranging from 220 to 280 nm. Biosynthesized FeNPs from actinobacteria significantly reduced the microbial growth of Fusarium oxysporum and L. monocytogenes, while they showed weak antimicrobial activity against P. aeruginosa and no activity against E. coli, MRSA, or Aspergillus niger. On the other hand, biosynthesized FeNPs showed strong antibiofilm activity against P. aeruginosa while showing mild and weak activity against B. subtilis and E. coli, respectively. The collaboration of biosynthesized FeNPs and key enzymes for bacterial infection exhibits hydrophobic and/or hydrogen bonding, according to this research. These results show that actinobacteria-biosynthesized FeNPs prevent biofilm development in bacteria.

Bioefficacy of Zinc oxide nanoparticle synthesis and their Biological, Environmental applications from Eranthemum roseum

Synthesis of metal oxide nanoparticles using medicinal plants increasing rapidly due to its eco-friendly to environment. In this study Zinc oxide nanoparticle is synthesized using the leaf extract of plant E. roseum. Synthesized NPs was characterized using UV- Vis Spectroscopy analysis where the peak observed at 374 nm with band gap of 2.5 eV, FTIR and XRD analysis validate pure hexagonal structure, Spherical shape of NPs was confirmed by SEM with EDX analysis and main compounds are zinc 75 % and oxygen 22 %. Transmission Electron Microscopy Analysis confirms the oval shaped ZnO NPs Biological activity of E. roseum ZnO NPs such as antioxidant assay DPPH, ABTS, hydroxyl radical activity shows good inhibition against free radicals. The In-vitro Hypoglycemic effects has maximum inhibition of 96 % on α- amylase activity and 87 % on α- Glycosidase activity. Anti-inflammatory activity recorded 93 % maximum inhibition at Albumin denaturation assay and 75 % at Membrane stabilization assay. E. roseum ZnO NPs shows 67.79 % on HepG2 Anti-proliferative cells line. AO/EtBr staining assays confirms the apoptosis effect. Larvicidal activity shows highest mortality of 98.44 % on species C. quinquefasciatus. Photocatalytic dyedegradation of Methylene blue dye shows 65 % of dye degradation.

Exploring conformational changes in β-lactoglobulin (β-LG) induced by silibinin: A comprehensive analysis of polyphenol-protein interaction

This study investigates the comprehensive characterization of the interaction between β-lactoglobulin (β-LG) and Silibinin using various spectroscopic techniques. Fluorescence quenching experiments at different temperatures (298, 303, 308, and 313 K) revealed substantive interactions between β-LG and Silibinin, as indicated by a reduction in fluorescence intensity and a red shift in emission maxima. Further analysis, including Stern-Volmer quenching constants (KSV), bimolecular quenching rate constants (kq), and thermodynamic parameters demonstrated static quenching mechanism and strong binding affinities (Ka range: 0.138–1.483 × 105 M−1) between BLG-Silibinin complex. Thermodynamic study suggested positive enthalpy and entropy changes (ΔHo=43.31 kcal mol−1; ΔSo=164.33 cal mol−1 K−1), suggesting a spontaneous reaction with negative ΔGo values (-5.66 to -7.30 kcal mol−1). Forster resonance energy transfer (FRET) measurements confirmed optimal distances (r and Ro) for FRET occurrence, endorsing the static quenching mechanism. Molecular docking supported these findings, showcasing a 1:1 stoichiometric binding ratio for β-LG: Silibinin. The β-LG and Silibinin complex is primarily stabilized by hydrogen bonds and hydrophobic interactions. Molecular dynamics simulations over 200 ns highlighted stability in the β-LG-Silibinin complex, indicated by RMSD convergence, consistent RMSF values, and compactness illustrated by Rg. Conformational changes in β-LG upon Silibinin binding were further confirmed through UV-Vis absorption spectroscopy, FTIR, far-UV CD, synchronous fluorescence, and 3D fluorescence analyses. Functionally, the antioxidant capacity of β-LG increased after complexation with silibinin as quantified by DPPH assay. These results collectively depict the intricate network of interactions between Silibinin and β-LG, shedding light on the molecular details of their binding and offering insights into potential functional implications in biological contexts.

Synthesis, characterization, in silico and in vitro assessment of 2-aminopyridine nicotinamide cocrystal as a new agent for breast cancer therapy

Breast cancer is the leading cause of cancer-related death among women globally, in spite of major advances in diagnosis and treatment. 2-Aminopyridine Nicotinamide (2APNA) cocrystal was synthesized and cocrystal formation was confirmed through powder XRD. Computational investigations in structural fields and spectroscopic parameters were conducted and compared with the experimental results. Comparing the optimized geometrical characteristics, it was observed that molecular properties of 2APNA closely match the previously reported experimental data. FT-IR and FT-Raman spectroscopic analysis revealed the theoretical wavenumbers agree better with recorded data and in UV–visible absorption a single peak was recorded at 247 nm showing n → π* transition. The 2APNA's stability, reactive nature, charge relocations were studied through quantum chemical calculation such as FMO, MEP, NBO, NLO and Mulliken charge analysis. The topological features of cocrystal 2APNA was examined through ELF, LOL and RDG studies. The anti-apoptotic protein BCL-2 was selected as a target in molecular docking analysis and the results expressed 2APNA's binding score as -8.2 kcal/mol. In vitro studies confirmed that 2APNA has 2APNA demonstrated an enhanced cell death in MCF-7 cells with the IC50 concentration of 56.58 µg/mL and decreased the expression of BCL-2, thus resulting in apoptotic cell death. These results indicated that 2APNA possess a potent anticancer property for the treatment of breast cancer.

Purification, structural characterization and immunomodulatory activity of a polysaccharide isolated from Scutellaria baicalensis stem-leaf

In our research, a novel polysaccharide (named SSP-3a) with uniform molecular weight was extracted from Scutellaria baicalensis stem-leaf. The structural analysis revealed that SSP-3a was an acidic polysaccharide with a heavy average molecular weight of 1.83 × 105 Da. By HPLC, the primary constituents of SSP-3a were mannose (11.60 %), glucuronic acid (42.99 %), glucose (23.43 %), and xylose (22.04 %). According to FT-IR and 1H NMR analysis, it was confirmed to be a β-configuration pyranose with a CO stretching vibrational peak. The immunomodulation results also showed that SSP-3a not only significantly promoted RAW264.7 cell proliferation and phagocytosis, but also stimulated the release of NO and cytokines. Furthermore, mechanistic studies suggested that SSP-3a had the ability to trigger MAPKs and NF-κB immunological signaling pathways via TLR4 receptors. The findings suggested that SSP-3a might be a beneficial active component for the food and pharmaceutical industries.

Valorizing Biopolyester Suberin: Modification of Cellulose Nanocrystals and Performance Assessment in 3D-Printed Biobased Acrylates.

Suberin, a common biomass processing waste, is a complex biopolymer and a promising source for the biorefinery of chemicals. Six different approaches for the extraction of birch outer bark suberin fatty acids (SFAs) were explored, and their application in grafting the surface of cellulose nanocrystals (CNCs) was investigated. Successful CNC functionalization was controlled with FTIR and NMR analyses. In-depth research allowed us to evaluate the interface of the nanocellulose and polymer matrix. Three structurally distinct SFA-grafted CNCs were integrated into a vegetable oil-based acrylate resin in an ultralow concentration of 0.1 wt %. Five biobased acrylic resin formulations were prepared: without reinforcement, with CNC, and with three distinct SFA-grafted CNCs. Vat photopolymerization (VP) 3D printing was utilized for sample preparation. The effects of grafted CNC components on 3D-printed samples' thermal stability, thermomechanical properties, and wettability were evaluated in detail. CNC functionalization enhanced the interface with the polymer matrix, yielding up to a 2-fold increase in elongation and up to a 2.5-fold increase in strength in tensile and flexural tests compared to the polymeric matrix. The CNC-SFA-modified filler demonstrated performance comparable to, or even better than, petroleum-based chemical modification routes found in the existing literature. This study highlights a promising approach for green functionalization of CNCs and verifies its use in interface enhancement using a biobased acrylate matrix.

Enhanced adsorption of malachite green (MG) dye using RF glow oxygen plasma-modified coconut carbon shell: A sustainable approach for effluent treatment

The textile industry produces dye pollutants that are both harmful and difficult to degrade. This study explores the enhanced adsorption of Malachite Green (MG) dye using coconut carbon shells treated with RF glow oxygen plasma discharge. Plasma treatment improved the surface properties of the adsorbent by introducing oxygen-containing functional groups and increasing surface polarity, which boosted dye adsorption through hydrogen bonding, electrostatic interactions, and π-π stacking. Experimental results revealed that a 10-minute plasma treatment optimally enhanced adsorption capacity by 39 % compared to untreated samples. The Langmuir isotherm model demonstrated a maximum adsorption capacity (qm) of 161 mg/g, surpassing the Freundlich model. At pH 8, using 0.2 g of adsorbent in 50 mL solutions with initial dye concentrations of 25 mg/L and 100 mg/L, the 10-minute plasma-treated samples achieved adsorption capacities of 6.01 mg/g and 23.95 mg/g, respectively, compared to 4.72 mg/g and 17.2 mg/g for the untreated samples. This corresponded to removal efficiencies of 96.12 % and 95.8 % for the treated samples, and 75.6 % and 68.8 % for the untreated samples, after 80 min of contact at 200 rpm. UV–vis spectrophotometry confirmed the reduction in dye concentration after adsorption. FE-SEM analysis revealed that plasma treatment created micro-pores on the coconut carbon shell, enhancing adsorption capacity, while SEM-EDX analysis showed increased oxygen content after 10 min of treatment. FTIR analysis identified additional carbonyl (-C=O) and hydroxyl (-OH) groups, indicating the incorporation of oxygen-containing functional groups due to plasma treatment. Confocal Raman microscopy was also used to analyze the microstructural changes in the samples.

Optical investigation of degradation of graphene oxide in alkaline environment: Evidence of two distinct photon-emitting phases in visible region.

In this work we show a procedure of treating of the graphene oxide in alkaline environment as a function of the treatment time in order to obtain novel structures with strong luminescence properties, water-stable, useful as potential replacement for critical raw materials employed as example in optical and optoelectronic devices or for diagnostic and therapeutic technology. These structures have distinct blue and green-luminescence properties which derived most likely from different structural conformations, one associable with that of carbon quantum dots (or as an alternative to that of the Oxidative Debris), the other, lighter and more similar to organic compounds, reported in literature as fulvic-like molecules, but whose nature has to be further investigated. We show that the lighter fraction has a dual mechanism of photoemission: the excitation-independent PL for excitation wavelength within 350 nm and the excitation-dependent component for excitation wavelength ranging in the visible spectrum. The PL dual behaviour could depend on fluorescent nanoclusters composed by specific organic fluorophores with a carbonaceous core. FTIR analysis shows reasonably the same functional groups unless of some difference discussed in the text, meanwhile UV–Vis and PL analysis clearly highlight two distinct emissions (450 nm and 530 nm) in the visible region of the electromagnetic spectrum. Excitation-dependent photoluminescence, water stability and organic fluorescent nanostructures are issues particularly required for application in the biological field but also in materials science.

Effect of Residual Cuts on Deactivation of Hierarchical Y Zeolite-Based Catalysts during Co-Processing of Vacuum Gas Oil (VGO) with Atmospheric Residue (ATR)

The influence of residual cuts on the deactivation of hierarchical Y zeolite-based catalysts during the co-processing of vacuum gas oil (VGO) with atmospheric residue (ATR) was investigated. The experiments were conducted in a laboratory-scale MAT-type reactor. The conversion of VGO, ATR, and their 70:30 (mass basis) mixture was examined using two composite catalysts: Cat.Y.0.00 and Cat.Y.0.20. The operating conditions closely resembled those of the commercial catalytic cracking process (550 °C and contact times of 10 to 50 s). When ATR was processed individually, the conversion remained below 50 wt%. However, significant improvements in conversion rates were achieved and catalyst deactivation was mitigated when ATR was co-processed with VGO. Notably, the BET surface area and average mesopore volume were adversely impacted by ATR, which also led to the accumulation of high levels of metals and nitrogen on the spent catalyst, detrimentally affecting its acidic and structural properties. Moreover, substantial coke deposition occurred during ATR cracking. The soluble and insoluble coke analysis revealed H/C ratio values of up to 0.36, indicative of polycondensed coke structures with more than ten aromatic rings. The nature of the coke was confirmed through TPO and FTIR analyses. Interestingly, the CatY.0.20 catalyst exhibited less activity loss, retaining superior acid and structural properties. Co-processing Colombian atmospheric residue with ATR loadings of 30 wt% (higher than the typical 20 wt%) in catalysts formulated with hierarchical zeolites presents a promising alternative for commercial applications. This research opens avenues for optimizing catalytic cracking processes.

Gamma radiation induced tailoring the structural, optical, surface and mechanical properties of UHMWPE

The present investigation examined how the resultant gamma radiation affected the ultra-high molecular weight polyethylene's (UHMWPE) mechanical, optical, surface, and structural characteristics. Different gamma doses of 75, 150, 250, and 350 kGy were applied to the UHMWPE samples. The study of physical and chemical qualities has involved a variety of spectroscopy techniques, including Fourier Transform Infrared spectroscopy, X-ray diffraction, mechanical property changes, and biocompatibility properties. New bands are formed, as indicated by FT-IR analysis, and this process is linked to the oxidation of irradiation polymer chains and the production of carbon dioxide. The crystallinity of irradiated samples increases as the gamma radiation increases, according to XRD patterns. The analyzed optical results exhibit improvements in the optical characteristics of the irradiated samples. The absorbance spectra of the irradiated samples showed a shift toward the high of wavelength values in the absorption edge as compared to the pristine sample. On the other hand, the optical absorption edge has an increasing tendency as the dose of gamma-ray radiation is increased. As the gamma-ray dose increases, the absorption edge moves toward the longer wavelength. The measurements of the contact angle indicate that the surface free energy rises with increasing gamma irradiation. It was detailed how the mechanical properties of the irradiated UHMWPE samples were measured. The mechanical measurements indicate that the mechanical properties are dose-dependent to some extent. Furthermore, as gamma doses rise, so does the hardness of irradiated UHMWPE.

Aqueous solubility enhancement of theobromine using eco-friendly hydrotropic phenomena

Theobromine, a bioactive compound found in cacao beans, is recognized for its pharmacological health benefits, such as improving heart health by lowering blood pressure, enhancing cognitive function, supporting respiratory health, providing antioxidant benefits, reducing inflammation, and promoting dental health. However, its limited solubility in water poses challenges for therapeutic applications, necessitating methods to enhance its solubility. The approach to enhance its bioavailability making it more effective for medicinal use and easier to incorporate into various pharmaceutical and nutraceutical products. Hydrotropic solubilization, utilizing the amphiphilic nature of sodium benzoate, is employed to improve the solubility of theobromine. Through systematic investigation of varying concentrations (0–3 mol/L) of sodium benzoate and temperature conditions ranging between 303 and 333 K, this study is aimed to elucidate their effects on the solubility of theobromine. Standardized protocols were utilized to measure the concentration of dissolved theobromine in sodium benzoate solutions, while thermodynamic properties were analyzed to understand the underlying mechanism. The study discovered that the solubility of theobromine was enhanced by sevenfold in the presence of sodium benzoate. Thermodynamic analysis revealed the solubilization process to be entropy-driven. Additionally, contact angle estimations confirmed increased hydrophobicity with higher sodium benzoate concentration, facilitating the solubilization of theobromine in the aqueous phase. Furthermore, FTIR analysis indicates that the solubilization of the bioactive compound occurs exclusively subsequent to traversing the minimum hydrotropic concentration (MHC).

Biochar aging, soil microbiota and chemistry of charcoal kilns in Mediterranean forests

AbstractCharcoal kilns, old structures used for charcoal production in the forest, preserve a charcoal-enriched topsoil representing a suitable proxy for studying the long-term effect of biochar addition to soil. Two kiln platforms located at Gelbison and Vesole mountain sites in Southern Italy were selected due to their comparable climates but distinct parent rocks. We conducted standard soil chemical analyses and used next-generation sequencing to explore bacterial and fungal microbiome. Anthracology identified charcoal species, while scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDS) characterized charcoal particles. Reflectance Fourier transform infrared spectroscopy (DRIFTS) assessed biochar surface oxidation. Additionally, a bioassay with soybean, maize, and Tomato investigated the impact of kiln soil on plant performance. Our results showed that kiln soils did not exhibit higher pH, cation exchange capacity, or greater richness in cations. EDS and FTIR analyses showed that charcoal buried in forest soil for decades undergoes significant oxidation, with increased O/C ratio and the presence of oxygenated functional groups. Charcoal surfaces were selectively enriched with Ca2+ on limestone substrate sites but with Al and Si over sedimentary (flysch) substrate. While differences in the kiln soil and its surroundings were noticeable, they were not drastic in terms of microbial diversity and composition. Surprisingly, the bioassay indicated that the kiln microbiota had a more positive impact on plant growth compared to external forest soil. In conclusion, this study highlights the unique nature of kiln microsites and begins to unveil the enduring effects of charcoal accumulation on soil chemistry and microbiota in forest soil. Graphical Abstract