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This work presents a way to use ethanol and spent coffee grounds (SCG) as feedstocks for biodiesel production to solve ethanol overproduction in Thailand and biodiesel feedstock shortage problems together. Waste coffee oil (SCGO) was ethanolic extracted from SCG; then, ethanol-SCGO mixture was transesterified in supercritical condition without ethanol removal. The ethanolic extraction curves of SCG at a temperature range of 50–70 °C were constructed. Transesterification experiments were studied in a batch reactor and a continuous reactor at various temperatures (275–350 °C) and reaction time (5–40 min) under 15.0 MPa. The molar ratio of ethanol-oil mixture was set at 30:1. The highest ester content of 88.37 ± 3.00 wt% was found in biodiesel obtained at a temperature of 275 °C and a reaction time of 40 min in a batch reactor. Furthermore, excess temperature (< 300 °C) and reaction time (< 20 min) induced thermal degradation and promoted the loss of ethyl linoleate. For continuous reactor, the maximum ester content of 83.38 ± 5.86 wt% was observed at 325 °C and 29.4 min of residence time. Unlike in batch reactors, thermal degradation of ethyl linoleate was not observed in a continuous reactor. The results showed that ethanolic extraction and supercritical transesterification are alternative ways to produce biodiesel from SCG without removing extractant and using catalyst. From a prospective point of view, techno-economic analysis (TEA) and life-cycle assessment (LCA) of invented process should be conducted to ensure profitability and environmental benefits, respectively. [ABSTRACT FROM AUTHOR]

In this research, bimetallic CdNi nanoparticles encapsulated in a magnetic spent coffee ground (Fe3O4@COFF/CdNi) was synthesized as a new nanocatalyst. The structural and chemical characteristics of Fe3O4@COFF/CdNi were comprehensively investigated using various techniques, including FT‐IR, XRD, XPS, TEM, VSM, EDS, TGA, BET, and ICP. Through XRD, XPS analysis, TEM images, and EDS mapping, the presence of CdNi nanoalloys was conclusively established. Fe3O4@COFF/CdNi exhibited remarkable catalytic activity for the hydrogen generation from water using iso‐propanol as a clean sacrificial agent. The high catalytic performance of Fe3O4@COFF/CdNi was attributed to the synergistic cooperative effect of Cd and Ni within CdNi nanoalloys. Interestingly, this process was performed for the in situ generated hydrogen from water to reduce a range of nitrobenzenes simultaneously into the corresponding anilines in high yields (93%–98%). The magnetic and hydrophilic characteristics of Fe3O4@COFF/CdNi facilitated its reusability over five runs. Using water as the most abundant hydrogen source, for the first time for in situ hydrogen generation–reduction of nitrobenzenes without demanding on external light sources or power supplies can be mentioned as a significant milestone of this field of study. [ABSTRACT FROM AUTHOR]

• Biochar accelerated the conversion of acetic and propionic acids in AnMBR. • Biochar enriched the functional bacteria degrading polysaccharides and protein. • Biochar facilitated the enrichment of autotrophic methanogenic bacteria. • Biochar increased c-type cytochromes-mediated DIET. • SCG-BC has a high electron accepting and donating capacities of 0.0362 ± 0.002 mmole− g−1. A biochar-assisted anaerobic membrane bioreactor (BC-AnMBR) was conducted to evaluate the performance in treating swine wastewater with different organic loading rates (OLR) ranging from 0.38 to 1.13 kg-COD/(m3.d). Results indicated that adding spent coffee grounds biochar (SCG-BC) improved the organic removal efficiency compared to the conventional AnMBR, with an overall COD removal rate of > 95.01%. Meanwhile, methane production of up to 0.22 LCH 4 /gCOD with an improvement of 45.45% was achieved under a high OLR of 1.13 kg-COD/(m3.d). Furthermore, the transmembrane pressure (TMP) in the BC-AnMBR system was stable at 4.5 kPa, and no irreversible membrane fouling occurred within 125 days. Microbial community analysis revealed that the addition of SCG-BC increased the relative abundance of autotrophic methanogenic archaea, particularly Methanosarcina (from 0.11% to 11.16%) and Methanothrix (from 16.34% to 24.05%). More importantly, Desulfobacterota and Firmicutes phylum with direct interspecific electron transfer (DIET) capabilities were also enriched with autotrophic methanogens. Analysis of the electron transfer pathway showed that the concentration of c-type cytochromes increased by 38.60% in the presence of SCG-BC, and thus facilitated the establishment of DIET and maintained high activity of the electron transfer system even at high OLR. In short, the BC-AnMBR system performs well under various OLR conditions and is stable in the recovery energy system for swine wastewater. [Display omitted] [ABSTRACT FROM AUTHOR]

Based on the suitability of the raw materials and treatment processes as well as the structural differences and complementarities of activated carbon prepared from coffee grounds (CG) and sludge, this study proposed a strategy to blend various sludge with the higher (50.91%) and lower (34.19%) ash contents into CG to prepare porous activated carbon for CO2 adsorption. Compared with sludge with higher ash content (HS), the activated carbon prepared from sludge with lower ash content (LS) had superior defect degree and carbon skeleton stability. Moreover, the activated carbon (CLSAC-20) derived from LS blended into coffee grounds under a ratio of 20% continued to optimize the structure of that from coffee grounds (CAC), which is mainly microporous. This was attributed to the LS exhibiting the structure-oriented role, which increased the pore volume (from 0.664 to 0.766 cm3/g) and specific surface area (from 1217.84 to 1355.65 m2/g). Because of the structural improvement achieved by LS blending, the CLSAC-20 had a better CO2 adsorption capacity (3.75 mmol/g) than CAC (3.27 mmol/g). Both were superior to commercial activated carbon (2.6 mmol/g) and the adsorption efficiencies still maintained above 90% after 5 cycles of regeneration. In summary, this study developed a simple, efficient, and environmentally friendly strategy to convert organic solid waste into high-value-added CO2 adsorbent. [ABSTRACT FROM AUTHOR]

Groundwater contains high levels of dissolved ions, which pose health risks when consumed. This study proposes biochar production for fluoride (F-) removal from aqueous solutions using sustainable materials and functionalization processes. Biochar derived from coffee grounds carbonization at 500 ℃ was functionalized with hydrogen peroxide (H2O2). Structural morphology analysis utilized SEM+EDS, BET, and BJH techniques, while XRD and FTIR analyses assessed surface chemistry. Effects of pH, dosage, and initial F- concentration on adsorption were evaluated, along with kinetics and thermodynamics.H2O2 increased acid functional groups on the surface without significantly altering surface area or pore volume. The highest adsorption capacity (0.179 mg g-1) and removal efficiency (25.5%) were at pH = 4. Kinetic studies highlighted the influence of initial F- concentration on adsorption equilibrium time and capacity. Experimental data fitting to pseudo-second-order and Elovich models suggested chemical mechanisms predominance, with intraparticle diffusion as the rate-limiting step. Adsorption isotherm fitting to Langmuir and Freundlich models indicated physical and chemical processes combination. The highest adsorption capacity was recorded at 1.46 mg g-1 at 55 ℃. Thermodynamic analysis revealed endothermic and nonspontaneous nature, potentially affecting F- affinity towards the adsorbent. [ABSTRACT FROM AUTHOR]

Increased consumption of coffee in the world leads to the accumulation of food waste that is not properly utilised properly, but have prospects for further processing into a targeted with added value. The aim of this study is to produce biochar from waste coffee grounds by coffee grounds by conventional pyrolysis and microwave irradiation, determination of its chemical and particle size distribution, study of acid-base and ion exchange properties, ability to bind ions and lead ions for further use as an additive in the production of biogas production. Given the high cost of conventional pyrolysis to produce the required volumes of biochar, it is promising to consider an alternative option that will be significantly cost-effective and efficient. After carbonisation, we determined the biopolymer composition, acid-base and ion exchange properties of the raw materials and biochar using various methods, such as the Kjeldahl Hogedron-Jensen, potentiometric titration and others. The results of the maximum cation exchange capacity of raw materials and biochar indicate that biochar has a less pronounced tendency to exchange cations in the range of 0.89-1.15 µeV/g than raw materials, the value of which is mainly in the range of 1-3 µeV/g, which shows less influence of biochar on the mineral balance of microorganisms during anaerobic digestion. The values of the anion exchange capacity of biochar are in the range of values 0.7-1.2 µeV/g, and the pH value of the acidic groups of biochar lie in the range of 7.1-10.7 (characterising them as weakly acidic groups), pKa is 9.6-10.7. The curves of potentiometric titration of biochar are determined by the additive contribution of all ionised groups of biochar and allow us to classify the studied products as polyfunctional ion exchangers type ion exchangers. Results of the study of biochars from waste coffee grounds show that they have ampholytic properties and act as acceptors of metal ions, as well as function as a mild pH regulator, which is important in anaerobic digestion of food waste into biogas to increase the yield of the resulting gas in accordance with the biocircular green economy model. [ABSTRACT FROM AUTHOR]

Supercapatteries combine the high-power density characteristic of supercapacitors with the high energy density typically found in batteries, offering a promising solution for advanced energy storage applications. We present an efficient two-step method to fabricate hierarchical, binder-free NiCo layered double hydroxide (LDH) nanosheet arrays supported on polyaniline layered nickel foam (NF). A PANI@NiCo-LDH/NF nanocomposite serves as the anode in the supercapattery, leveraging the high capacitance and improved conductivity of the combined materials, yielding a significantly high specific capacity of 1481 C g−1 (3703.33 F g−1). Coffee grounds derived reduced graphene oxide (rGO), providing a sustainable and environmentally friendly material with excellent electrical conductivity and high mechanical strength, serves as the cathode. The synergy between the PANI@NiCo-LDH/NF anode and the rGO cathode creates a novel and highly efficient supercapattery system. The fabricated supercapattery device offers an energy density of 54.44 W h kg−1 at a power density of 0.702 kW kg−1 and exhibits good cyclability with capacitance retention of 84.88% and Coulombic efficiency of 77.68% over 5000 charging/discharging cycles. This innovative approach addresses the limitations of traditional energy storage devices, paving the way for more versatile and sustainable energy solutions. [ABSTRACT FROM AUTHOR]

The growing popularity of cold-brewed coffee has resulted in large amounts of localized spent coffee grounds (SCG) generated from production plants. Spent coffee grounds offer many favorable agronomic properties, but also contain caffeine, tannins and phenolic compounds that may be deleterious to plant growth. There is a growing body of research examining the effects of SCG on plants, but little of which pertains to use in turfgrass systems. The objective of this two-year field study was to evaluate the feasibility of using SCG as an agronomic source of nutrients for turfgrass. Field studies were conducted over two years to characterize performance of 'Riley's Super Sport' (Celebration®) bermudagrass (Cynodon dactylon) receiving multiple nutrient source treatments including fresh and composted SCG, as well as synthetic, natural organic, and bridge fertilizers, some which included SCG. Soils were analyzed at the conclusion of the study to determine whether SGC provided long-term effects of on soil pH and/or nutrient concentrations. Our results demonstrated that although SCG possesses between 2.3-2.9% N and a favorable C:N ratio, direct SCG applications over two seasons did not produce responses typical of a fertilizer when applied as a topdressing. However, when combined with poultry litter, the SCG-containing organic fertilizer GeoJava produced improved turf quality relative to other organic and synthetic commercial fertilizers in our study, including Milorganite, ammonium sulfate, and URI-PEL S.R. Further, despite the acidic nature of SCG, their repeated application over multiple years did not result in any long-term changes to soil pH. Although early on, SCG treatments caused mild and transient phytotoxicity, these effects were not observed when it was applied in combination with the manure used in GeoJava. [ABSTRACT FROM AUTHOR]

Material extrusion additive manufacturing is increasingly popular but requires new materials to expand its industrial applicability. This study compares the effects of two bio‐fillers (lignin and spent coffee grounds (SCG)) in a bio‐polymer matrix, polylactic acid (PLA). The bio‐fillers aim to enhance the sustainability of the resulting composites, tune their physical properties (rheology, thermal stability, mechanical resistance and water absorption) and improve 3D‐printability by reducing the temperature at the nozzle. The composite with 15 wt.% SCG exhibited an elongation at break of 22.95% (vs. 8.42% for PLA), a printing temperature of 180°C (vs. 215°C for PLA) and a water absorption after 6 weeks immersion in water of 18.77 wt.% (vs. 5.04 wt.% of PLA), suggesting applications like hydroponic farming. Moreover, small amounts of SCG protected the composite against thermo‐oxidative degradation during extrusion, while lignin enhanced the thermal stability of the composite. Highlights: 15 wt.% SCG improved PLA ductility (elongation at break 22.9% vs. PLA's 8.4%).Lower printing temperature (180 vs. 215°C for PLA) was achieved with 15 wt.% SCG.SCG protects composite from thermo‐oxidative degradation.15 wt.% SCG in PLA absorbs 18.77% water after 6 weeks (vs. 5.04% of PLA).Lignin boosts thermal stability of PLA composite. [ABSTRACT FROM AUTHOR]

This work aims to allocate coffee grounds waste to the production of biochar from pyrolysis under different temperatures (350 °C and 500 °C), to add value to it. The resulting materials were characterized by immediate, elemental, thermogravimetric analysis, SEM, FT‐IR, XRD and Raman spectroscopy. Additionally, the need to activate the biochar produced for the desired use was evaluated. The obtained biochars were applied in electroanalysis in the manufacture of modified carbon paste electrodes. This choice was made due to the possibility of reaching a high sensitivity towards the determination of Cu2+ ions. The differential pulse adsorptive anodic stripping voltammetry technique was applied to perform the Cu2+ determination and, in this case, several parameters were optimized, including biochar' percentage, pH of pre‐accumulation step and reduction/stripping step, pre‐accumulation time, potential and time of reduction of adsorbed‐Cu2+. From this, the proposed modified electrode showed a linear voltammetric response towards Cu2+ in the range of 66.1 to 3997.3 ppb, with a limit of detection of 31.8 ppb, in addition to having been satisfactorily applied in the analysis of water samples (recoveries close to 100 %). Thus, demonstrating the potential for reuse of discarded coffee grounds for the preparation of activated biochar with outstanding electrochemical performance. [ABSTRACT FROM AUTHOR]

Practical Application Spent coffee grounds (SCG) are the waste byproducts of coffee brewing. While SCG can be valorized to produce functional biopolymers due to their valuable structural components, the lignocellulosic structure of SCG is resistant to degradation because of the tightly bound lignin. Therefore, a pretreatment step is required before pulping with peracetic acid (PAA), an eco‐friendlier alternative to traditional pulping methods, to facilitate the extraction of these desired cellulosic materials. Formic acid:acetic acid:deionized water (FA:AA:W = 30:50:20) or 60% (v/v) ethanol pretreatments were applied to SCG to compare the characteristics of the resulting cellulosic materials after PAA pulping. Lignocellulose analysis showed that the lignin content (7.06%) of ethanol pretreated SCG was significantly lower (p < 0.05), and the cellulose content (29.52%) was significantly higher (p < 0.05) than the untreated SCG (15.50% and 11.50%, respectively), indicating that an adequate amount of lignin was removed to obtain the cellulosic materials after the pretreatment process. Morphological and structural changes in the lignin and hemicellulose were observed in all the pretreated SCG, which further confirmed that these components were degraded with pretreatments and pulping. Ethanol pretreated SCG showed the most optimal results based on the greatest lignin decrease seen from its lignocellulose composition, appearance, and structure. This study exemplified a conversion process to extract cellulosic materials from SCG more efficiently to utilize for cellulose‐based products and verify its potential to be valorized as a waste byproduct.Coffee companies can provide the spent coffee grounds (SCG) they produce to develop cellulose‐based materials to make biodegradable packaging products rather than throwing them out or burning them. Using SCG for producing cellulose‐based materials can help promote sustainability and reduce food waste worldwide. SCG can be utilized as an alternative source based on their abundance and desired biopolymeric properties, providing innovative solutions to industries and increasing consumer awareness of this cause. [ABSTRACT FROM AUTHOR]

This study investigates the valorization of spent coffee grounds (SCGs) through protein extraction and their application in mycelium-based packaging and renewable energy pellets. Three extraction methods—mechanical stirring, ultrasound-assisted, and CO2-assisted extraction—were applied to SCGs. CO2-assisted extraction yielded the highest protein content at 34.24%, followed by mechanical stirring (31.46%) and ultrasound-assisted extraction (28.51%). The total polyphenol content and antioxidant capacity were also highest in the CO2 extracts, suggesting that this method preserves bioactive compounds most effectively. After protein extraction, SCGs were tested as a component in mycelium-based packaging, with results showing an apparent density of 0.551 g/cm3 and compression resistance of 3.354 MPa, indicating its suitability for structural applications. The energy value of SCGs remained high, with a calorific value of 19,887 J/g DW, slightly decreasing after extraction but still sufficient for renewable energy production. These findings highlight the potential of SCGs as a multi-functional resource, contributing to sustainable solutions across various industries. [ABSTRACT FROM AUTHOR]

Levels of mineral oil hydrocarbons were measured in a large range of green and roasted coffee beans or ground powder. To better understand the consumer exposure to mineral oil hydrocarbons, the transfer to the brewed coffee was assessed under three different preparations. As a result, less than 5% of mineral oil hydrocarbons were transferred to the cup. With this low transfer rate, the coffee contribution to the mineral oils daily intake can be assessed to be very low, below 0.8% of the total exposure. [ABSTRACT FROM AUTHOR]

The article delves into the CIA's failed attempt to disrupt the Guatemalan coffee industry in 1954 as part of a covert operation to overthrow President Jacobo Árbenz. While the operation, codenamed Operation FIBER, aimed to destabilize the government by disrupting coffee exports, it ultimately failed due to misconceptions about the industry and resistance from the U.S. coffee industry. The CIA's involvement in Guatemala's coffee industry was complex and intertwined with U.S. financial interests, highlighting the challenges of using economic warfare tactics in a globalized industry. Despite efforts to apply economic pressure through propaganda campaigns urging consumers to boycott Guatemalan coffee, the operation did not achieve its intended goals, showcasing the complexities of the transnational coffee trade. [Extracted from the article]

Featured Application: Storage conditions for solid sidestreams for improved shelf-life and safety of upcycled products such as food, feed, and value-added products. Brewer's spent grain (BSG) and spent coffee ground (SCG) are solid sidestreams from beverage production increasingly being upcycled into food, feed and other value-added products. These solid sidestreams are prone to microbial spoilage, negatively impacting their upcycling potential. Three samples each of BSG and SCG were obtained from generators and recycling facilities in Singapore, and their chemical, elemental, and microbial composition was characterized. The spoilage mechanisms were investigated during storage under anaerobic and aerobic conditions. Bacterial loads of sidestreams were low from craft brewery and café sources (<1 and 3.53 ± 0.03 log10 CFU/g) and high from recycling facilities (>6 log10 CFU/g). The microbiome of BSG from recycling facilities was dominated by Bacilli, and B. coagulans was identified as the most prevalent species. SCG from recycling facilities was dominated by lactic acid bacteria, with L. panis being the most prevalent species. Storage up to 14 days under anaerobic conditions led to further bacterial proliferation mainly by Bacilli, lactic acid bacteria, and acetic acid bacteria, while aerobic storage led to extensive fungal contamination, including potential aflatoxin-producing Aspergillus flavus. The results shed light on the spoilage mechanisms, while highlighting the short shelf-life and food safety risks of BSG and SCG to inform valorization strategies. [ABSTRACT FROM AUTHOR]

Due to its biodegradability, biocompatibility, and mechanical properties, poly‐lactic acid (PLA) is a leading biomaterial for numerous applications, especially for fused deposition modeling and fused filament fabrication. Nonetheless, the absence of a comprehensive recycling strategy may emerge as a significant source of plastic pollution in the future. Indeed, the polymer undergoes deterioration during melt recycling, resulting in a decrease in some mechanical properties that can compromise recyclability. To improve the properties of recycled PLA, the utilization of organic fillers coming from renewable materials can be considered as a sustainable solution. The objective of this work is then to evaluate the effect of recycling (reprocessing) on a virgin raw material as well as on biocomposites based on spent coffee grounds (incorporating 5% of spend coffee grounds in weight). The different types of filaments are extruded and re‐extruded and characterized under tensile, melt flow index, and hardness tests. The results show that the increase in the number of extrusions whether for virgin PLA or the composite contributes to the diameter fluctuation. Regarding the tensile properties, the rise in the frequency of recycling shows a weakness in the tensile strength and the elongation at break. On the other hand, Young's modulus values exhibit fluctuations. Concerning the addition of the spent coffee grounds filler, no major enhancement is observed in the tensile strength and the elongation at break, which is attributed to the poor adhesion between the matrix and the filler. The recycling process affects the hardness values of PLA, leading to an increase in these values, as well as those of the composite, which can be associated with the increased crystallinity caused by the recycling process and the SCG incorporation. Highlights: Recycling and reusability strategy for poly‐lactic acid (PLA) and PLA/spent coffee grounds (SCG) filaments.Assessment of recycling effects on PLA and PLA/SCG.Mechanical characterization through tensile and hardness testing. [ABSTRACT FROM AUTHOR]

Coffee is one of the most consumed beverages worldwide. Its production generates a large amount of waste, and its use is of vital importance to prevent it from becoming a source of environmental pollution. Cuba is a country with a well-known coffee-growing tradition. Although coffee production has decreased, it is vitally important to use the waste generated in these productions to reduce environmental pollution. To know the possible use or application of coffee waste, it is necessary to know its composition. In this article, three Cuban Arabica coffee wastes (husk, parchment and spent coffee grounds) were characterized using chemical, physical and physicochemical methods. In the characterization of these wastes, SEM and EDX were used to determine their microscopic form and chemical composition. The Chesson–Datta method, ATR and TGA were used to determine whether these materials were lignocellulosic. Ash, pH and density of the waste were determined as characterization methods. The extractive content was determined and a phytochemical screening was performed to determine the groups of the secondary metabolites present. [ABSTRACT FROM AUTHOR]

The integration of biochar (BC) production from organic waste with ampicillin (AMP), an emerging pollutant, adsorption is a novel and promising treatment approach. In this study, peanut shells, coffee grounds, digestates, and oyster shells were used for BC production. Among these, the use of anaerobic digestate from food waste fermentation to produce extracts for antibiotic adsorption is relatively unexplored. The pyrolysis temperature was determined using thermogravimetric analysis (TGA) and the materials were characterized with BET, SEM, FTIR, and XRD. The TGA results indicate that PSB, CRB, and DSB underwent pyrolysis involving cellulose, hemicellulose, and lignin, whereas OSB underwent crystal formation. Characterization revealed that DSB has more functional groups, a superior mesoporous structure, appropriate O/C ratio, and trace amounts of calcite crystals, which are favorable for AMP adsorption. Adsorption experiments demonstrate that all four materials adhere to the Freundlich and Langmuir isotherm and Elovich kinetic models, indicating predominant physical adsorption, with some chemical adsorption also present. Thermodynamic studies demonstrate that BC is spontaneous during adsorption and is a heat-absorbing reaction. DSB exhibits the strongest AMP adsorption. A 53.81 mg g−1 adsorbance was obtained at a dosage of 150 mg, pH = 2, and 60 °C. This study introduces innovative approaches for managing waste types and provides data to support the selection of suitable solid wastes for the preparation of BC with excellent adsorption properties. Furthermore, it lays the groundwork for future studies aimed at enhancing the AMP treatment efficacy. Preparation and characterization of biochar and adsorption mechanism of ampicillin in water. [ABSTRACT FROM AUTHOR]

Because the earthworm tegument represents their first barrier against environmental aggressions, we hypothesised that substrate-induced changes in earthworm growth would also alter the morphology of this protective layer. Therefore, a histological and morphometric study was performed on Eisenia fetida specimens that have been grown in five different organic residues: cow manure, horse manure, grape marc, coffee grounds, and a mixture of coffee grounds and cooking oil. The results showed that, across all treatments, both cuticle and epidermis were significantly thicker in the pre-clitellar region than after the clitellum, attributed to the fact that the former region is responsible for breaking up the soil. Notably, the growing media significantly altered the thickness of these two integumentary layers, and the greatest thicknesses were measured in grape marc and in the mixture coffee grounds + cooking oil, which makes them suitable organic residues for vermicomposting. By contrary, a significant epidermal thinning was observed when growing on coffee grounds alone, clearly indicating that it is a hostile environment for earthworms. Overall, these results reveal that tegument thickness can be used not only as a trait indicator of substrate quality but also of earthworm welfare, and it should be integrated in future toxicity assessment and captive breeding guidelines. [ABSTRACT FROM AUTHOR]

Yearly, thousands of tons of wasted coffee grounds are produced according to high coffee consumption. Still, after the coffee brewing, wasted coffee grounds contain some amounts of caffeine (CAF). CAF, in turn, contains multiple O and N chelating atoms in its structure. These have a potential to be reductors for complexes of metals. In this context, within the present study, a set of CAF extracts derived from coffee beans and coffee grounds were obtained and then used for the one-step reduction of ReO4− ions with no additional toxic chemicals. Within this approach, CAF was applied as a secondary, green resource for the synthesis of unique rhenium nanoparticles (ReNPs) containing Re species at 0 and +6 oxidation states. The obtained ReNPs were identified and characterized with the use of X-ray powder diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM). Further, the capping and stabilization of ReNPs by CAF were verified with the aid of Fourier transformation infrared spectroscopy (FT-IR). The so-obtained "green" ReNPs were then used as a homogenous catalyst in the catalytic hydrogenation of 4-nitrophenol (4-NP). This new nanomaterial revealed a superior catalytic activity, leading to the complete reduction of 4-NP to 4-aminophenol within 40–60 min with a first-order rate constant of 0.255 min−1. [ABSTRACT FROM AUTHOR]

Urolithiasis, a common and recurrent condition, imposes a significant global health burden. This study investigates the causal relationship between various types of fluid intake and urolithiasis using univariable and multivariable Mendelian randomization (MR) approaches. Genetic data for urolithiasis were obtained from the FinnGen Consortium (n = 400,681), while genetic measures for nine fluid types were sourced from meta-analyses of genome-wide association studies (GWAS). The analysis revealed that genetically predicted coffee intake (OR: 0.571, 95% confidence interval (CI): 0.341–0.958, p = 0.034) and ground coffee intake (OR: 0.219, 95% CI: 0.005–0.923, p = 0.038) were protective factors for upper urinary calculi. Additionally, a standard deviation (SD) increase in tea intake was associated with a 53% reduction in risk (OR: 0.473, 95% CI: 0.320–0.700, p < 0.001). Conversely, milk intake (OR: 1.072, 95% CI: 1.018–1.130) and alcohol intakefrequency (OR: 1.304, 95% CI: 1.083–1.570, p = 0.005) increased the risk of upper urinary calculi. These findings highlight the association of tea with reduced risk of urolithiasis, instead for milk and alcohol intake, in formulating prevention strategies for urolithiasis. [ABSTRACT FROM AUTHOR]

Using biological/renewable resources as filler or modifier in both thermoplastics and rubbers has been of a great interest in order to reduce negative effects of traditional petroleum/natural gas based fillers. In this study, the main goal was the use of spent (waste) coffee grounds as a natural alternative filler to carbon black in acrylonitrile butadiene rubber (NBR) based compounds. Carbon black (CB) was partially replaced with fresh as well as spent coffee grounds (SCG) in NBR compound formulation. Stabilization effect of fresh coffee grounds was also investigated. Cure characteristics, physico‐mechanical, thermal, morphological, and dielectric properties of the bio‐based composites were tested and compared with the control (reference) compounds. Processability has been affected positively in the case of using coffee grounds thanks to the presence of triacyl groups in coffee. Up to 20% higher elongation at break values were measured when coffee is partially replaced with CB. Abrasion loss and oil resistance could be retained for coffee containing compounds. In conclusion, SCG were found to be a good natural alternative filler for bio‐based NBR composites without a significant change in material properties. Highlights: Spent coffee grounds ‐ a sustainable filler in bio‐based NBR compositesBoth fresh and spent coffee grounds are successful stabilizersPhysico‐mechanical, thermal, and dielectric properties are comparable [ABSTRACT FROM AUTHOR]

Gallium and indium, metals present in light-emitting diode (LED) lighting technology, can be effectively recovered from aqueous solutions by sorption. For this purpose, carbonaceous materials, such as activated carbon, or low-cost biosorbents as beer bagasse, spent coffee grounds or peanut shells, and a low-cost zeolite as chabazite, were characterized by BET, FTIR, XRD, and SEM analysis prior use. Protonated chabazite, with high surface area (505 m2/g) and a Si/Al molar ratio of 3.4, showed high sorption capacities for gallium (56 mg/g) and indium (92 mg/g), which is 10 to 30 times higher than those of our carbonaceous materials (T = 298 K, pH < 3, dosage = 1 g/L). Sorption experiments with both metals in solution showed a competitive effect between gallium and indium for the sorption sites of the chabazite, showing more affinity toward gallium than indium. Ga3+sorbed/In3+sorbed molar ratio above 2 was achieved for the same initial concentration of both metals, increasing to almost 3 when the initial gallium concentration increased, which was appropriate since gallium concentration tends to be higher in LED chips. However, the sorption capacity for both metals was always around 0.35 mmol Ga + In/g. The selectivity of the chabazite was conditioned by different behavior of both metals in aqueous solution at the sorption pH (below 3.5) being the predominant species in solution Ga(OH)2+ for gallium and In3+ for indium. Sorption with protonated chabazite can be used in the treatment of spent LEDs leachate for the dual purpose of water purification and selective metal separation. [ABSTRACT FROM AUTHOR]

In this study, poly(butylene adipate‐co‐terephthalate) (PBAT) biocomposites were generated from spent coffee grounds (SCGs) or torrefied SCG (TSCGs) using a melt compounding process. TSCGs were obtained at torrefaction temperatures of 230, 245, 260, 275, or 290°C for a duration of 60 min. Torrefaction enhanced the hydrophobicity, grindability, and biomass stability of the resulting composites by eliminating hemicellulose. Various concentrations of SCGs (10 and 20 wt.%) and TSCGs (10, 20, and 30 wt.%) were compounded into PBAT. The thermal, mechanical, and degradation properties of PBAT biocomposites were investigated. As SCGs and TSCGs were introduced, the crystallization temperature drastically increased. Compared with PBAT biocomposites with SCGs, PBAT biocomposites with TSCGs exhibited higher thermal stability and hydrophobicity, and improved mechanical properties. Further, alkaline hydrolysis occurred at a faster rate for biocomposites with biofillers than for neat PBAT. Therefore, this study demonstrated the improved compatibility between SCGs and PBAT by torrefaction. [ABSTRACT FROM AUTHOR]

The effect of spent coffee grounds (SCG) aqueous extract and butylated hydroxytoluene (BHT) on color deterioration, lipid oxidation, and antioxidant status of uncooked pork patties during refrigerated storage (4 °C/9 days, under dark) was investigated. Polyphenols content and antiradical activity of SCG extract were evaluated. Pork patties were evaluated for pH, color parameters and lipid oxidation (LOX), as well as total antioxidant activity of meat. Results showed that SCG extract is an important source of polyphenols and exerts antioxidant activity. Their inclusion in meat samples mitigated undesirable changes in pH, color, and LOX values and increased the antioxidant stability during storage (P<0.05). In conclusion, using SCG extract as a natural antioxidant can improve raw pork patties' quality and shelf life. [ABSTRACT FROM AUTHOR]

Background: This study investigates the associations between coffee consumption and metabolic syndrome and its components, as well as the effect of milk, sugar, and artificial sweeteners on these associations. Methods: A cross‐sectional analysis was conducted with 351805 UK Biobank participants. Coffee consumption data were collected via food frequency questionnaires and 24‐h recall. Metabolic syndrome was identified through blood biochemistry and self‐reported medication use. Odds ratios were calculated using multivariable logistic regression, and results were verified with two‐sample Mendelian randomization. Results: Consuming up to two cups of coffee per day was inversely associated with metabolic syndrome (1 cup/day: odds ratio [OR]: 0.88, 95% confidence interval [CI]: 0.85–0.92; 2 cups/day: OR: 0.90, 95% CI: 0.86–0.93). Higher intakes showed near‐null associations. Mendelian randomization did not support a causal link between coffee intake and metabolic syndrome. Both self‐reported and genetically predicted high coffee consumption (four cups per day or more) were associated with central obesity. The inverse association between coffee consumption and metabolic syndrome was more profound among drinkers of ground coffee than those of instant coffee. Results were similar when stratified by the use of milk and sugar, yet the use of artificial sweetener with coffee was positively associated with metabolic syndrome and all component conditions. Conclusions: Coffee consumption may increase the risk of central obesity but is unlikely to impact the risk of metabolic syndrome. The potential health effects of artificial sweeteners in coffee need further investigation. [ABSTRACT FROM AUTHOR]

The conversion of spent coffee grounds (SCG) into hydrochars has been the subject of extensive research in recent years, aimed at evaluating their potential for biofortifying foods and mitigating the plant toxicity linked to SCG. This study aimed to assess the physicochemical characterization and the impact of incorporating both activated (ASCG and AH160) and functionalized SCG (ASCG-Zn), as well as SCG-derived hydrochars (AH160-Zn), on cucumber yield and plant zinc content. The following physicochemical properties were analyzed: specific surface area, pH and electrical conductivity, polyphenols, and nuclear magnetic resonance. The by-products activated and functionalized with zinc were applied to cucumber crops grown in a greenhouse across multiple harvests. The activation of both SCG and H160 reduced the specific surface area of the particles. However, when these by-products were functionalized, their Zn content increased significantly, up to 7400 ppm. Concerning polyphenol content, the activated products showed levels ranging from 3.5 to 4.9 mg GAE/g. Regarding cumulative production, the treatments that showed the highest yields were the by-products activated and functionalized with Zn reaching 25 kg. Incorporating these by-products notably raised the Zn content in cucumbers, reaching 0.1 mg Zn per 100 g of fresh weight. The activated by-products demonstrated the highest Zn utilization efficiency. [ABSTRACT FROM AUTHOR]

Rising concerns over water scarcity, driven by industrialization and urbanization, necessitate the need for innovative solutions for wastewater treatment. This study focuses on developing an eco‐friendly and cost‐effective biochar‐zeolite composite (BZC) adsorbent using waste materials—spent coffee ground biochar (CGB) and steel slag zeolite (SSZ). Initially, the biochar was prepared from spent coffee ground, and zeolite was prepared from steel slag; their co‐pyrolysis resulted in novel adsorbent material. Later, the physicochemical characteristics of the BZC were examined, which showed irregular structure and well‐defined pores. Dye removal studies were conducted, which indicate that BZC adsorption reach equilibrium in 2 h, exhibiting 95% removal efficiency compared to biochar (43.33%) and zeolite (74.58%). Moreover, the removal efficiencies of the novel BZC composite toward dyes methyl orange (MO) and crystal violet (CV) were found to be 97% and 99.53%, respectively. The kinetic studies performed with the dyes and phosphate with an adsorbent dosage of 0.5 g L−1 suggest a pseudo‐second‐order model. Additionally, the reusability study of BZC proves to be effective through multiple adsorption and regeneration cycles. Initially, the phosphate removal remains high but eventually decreases from 92% to 70% in the third regeneration cycle, highlighting the robustness of the BZC. In conclusion, this study introduces a promising, cost‐effective novel BZC adsorbent derived from waste materials as a sustainable solution for wastewater treatment. Emphasizing efficiency, reusability, and potential contributions to environmentally conscious water treatment, the findings highlight the composite's significance in addressing key challenges for the removal of toxic pollutants from the aqueous solutions. Practitioner Points: A novel biochar‐zeolite composite (BZC) material has been synthesized.Excellent removal of dyes by BZC (~95%) was achieved as compared to their counterpartsThe kinetic studies performed suggest a pseudo‐second‐order model.BZC proves to be highly effective for multiple adsorption studies.Excellent reusability showed potential as a robust adsorbent [ABSTRACT FROM AUTHOR]

This study explores the production of bio-nutrients from bioactive compound-rich spent coffee grounds (SCG) and biochar (BC) through composting after inoculation with a biological agent and its impact on the growth performance of garden cress and spinach. The SCG was composted with six doses of BC (0, 5, 10, 15, 20, and 25%). The compost with 10% BC exhibited the best maturity, humification, and phytotoxicity index values of dissolved organic carbon (DOC), humification index (E4/E6), and germination index (GI). A metagenome analysis showed that compost starter enhanced the bacterial community's relative abundance, richness, and diversity in SCG and BC treatments. This improvement included increased Patescibacteria, which can break down noxious phenolic compounds found in SCG and BC. The BC enriched the compost with phosphorus and potassium while preserving the nitrogen. In plant growth experiments, the total chlorophyll content in compost-treated garden cress and spinach was 2.47 and 4.88 mg g−1, respectively, which was significantly greater (p ≤ 0.05) than in unfertilized plants and similar to the plants treated with traditional fertilizer. Overall, the results show that the compost of SCG + BC was well-suited for promoting the growth of garden cress and spinach, providing adequate nutrients as a fertilizer for these leafy vegetables. [ABSTRACT FROM AUTHOR]

Bacterial cellulose (BC) has emerged as a sustainable biomaterial with diverse industrial applications. This paper examines BC production through a circular economy framework, focusing on organic waste as a primary feedstock. It compares static and agitated cultivation methods for BC production, highlighting their advantages and limitations. Static cultivation using Gluconacetobacter xylinum yields high-quality cellulose films but is constrained by lower yields and longer incubation times. Agitated cultivation accelerates production but may affect fiber uniformity. This paper emphasizes sustainability by exploring organic waste materials such as coffee grounds, tea leaves, and food scraps as cost-effective nitrogen and carbon sources. These materials not only lower production costs but also support circular economy principles by converting waste into valuable products. BC produced from these waste sources retains key properties, making it suitable for applications in the textile and other industries. In addition, BC production can align with vegan principles, provided that all additives and processing methods are free of animal-derived components. The paper discusses BC's potential to replace synthetic fibers in textiles and reduce environmental impact. Case studies show successful BC integration into textile products. In conclusion, this paper calls for more research to optimize BC production processes and explore new industrial applications. Using organic waste in BC production can help industries adopt sustainable practices, reduce environmental footprints, and create high-value materials. [ABSTRACT FROM AUTHOR]

Gelatine hydrogels can be prepared using different cross-linking methods, such as enzymatic, physical or chemical. Unfortunately, in the case of chemical cross-linking, the typically utilized synthetic cross-linkers are harmful to human health and the environment. Therefore, in accordance with the principles of green chemistry and sustainable development, we have obtained compounds for the chemical cross-linking of hydrogel polymers from the processing of spent coffee grounds. In this study, gelatin/κ-carrageenan hydrogels are cross-linked using a bio-cross-linking agent from spent coffee grounds. Their physicochemical and thermal properties are compared with those of standard physical gels. The chemical cross-linking was confirmed based on FT-IR spectra, which demonstrated the formation of new covalent bonds between the oxidized polyphenols included in the extract from the spent coffee grounds and the amide groups present in the gelatine structure. Significant differences were also observed in morphology (SEM images) and other physico-chemical characteristics (gel fraction, swelling ability, hardness). The chemically cross-linked hydrogels in comparison to physically ones are characterized by a better developed porous network, a slightly higher gel fraction (64.03 ± 4.52% as compared to 68.15 ± 0.77%), and a lower swelling ratio (3820 ± 45% as compared to 1773 ± 35%), while TGA results show that they have better thermal stability. The research confirmed the possibility of using the developed natural cross-linking agent in the process of obtaining hydrogel materials based on bio-polymers. [ABSTRACT FROM AUTHOR]

Background Results Conclusion During the processing of spent coffee grounds (SCGs) several residues are obtained, which are mostly disposed of in landfills. There is an urgent need for a comprehensive waste management strategy for these residues. This study evaluates the potential of SCGs as a biofertilizer by assessing their effects on lettuce leaves and the release of antioxidants following in vitro digestion and fermentation.Lettuce plants were grown with different amounts of SCGs (0–150 g kg−1) in the substrate. High SCG concentrations in the soil generated lighter colored tissues, a decrease in the green color, less root development, and lower dry weight of leaves (P < 0.05). The SCG levels also affected the release of antioxidants by the final product. This effect was more pronounced in the digested fraction: applying the Ferric Reducing Antioxidant Power (FRAP) method, the addition of SCGs from 10 g kg−1 to 125 g kg−1 increased the amount of antioxidant from 43.88 ± 4.81 to 105.96 ± 29.09 μmol Trolox g−1 of dry weight (P < 0.05). The Indigo Carmine Reducing Capacity (ICRED) method also showed a similar trend, but in this case the highest value was obtained with 150 g kg−1 of SCGs (16.41 ± 3.93 mmol catechin g−1 of dry weight) (P < 0.05). Moreover, in the fermented fraction a significant increase in the antioxidant released was found with low levels of SCG(P<0.05), while lettuces fertilized with intermediate amounts of SCGs (25 and 50 g kg−1) presented the highest amount of insoluble antioxidant (P < 0.05).A compromise should be found in order to achieve a product with a high antioxidant capacity and an acceptable visual quality. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The production and consumption of coffee generates large amounts of waste which, if released into the environment, could cause unacceptable pollution. The search for alternatives for the use of these waste materials, namely coffee silver skin (CSS) and spent coffee grounds (SCG), is of great importance from an environmental and economic point of view. In this context, the present study was conducted to evaluate the use of CSS and SCG as mineral sources in order to strengthen their status as novel foods, which is currently not recognised. With the aim of validating the content of metals and metalloids in CSS and SCG, a comparative study of green and roasted coffee was also conducted. The results of the HR-ICP-MS analyses showed that coffee and coffee by-products contain high levels of macro essential elements: K (2387–35 993 mg/kg), Mg (1263–5298 mg/kg) and Na (82.6–170 mg/kg). Among the essential trace elements, Fe predominated with amounts between 41.8 and 728 mg/kg. The essential elements in the ultra-trace range (Mo, Cr, Co and Se) are found in amounts between 0.02 and 2.42 mg/kg. The content of toxic elements (Pb, As, Cd and Sn) is in the range of 0.01–0.25 mg/kg, which is below the maximum levels set by the EU Commission for these elements in foodstuff. However, the levels of Rb, Ba, Sr, Ti and Al are high, and range from 2.33 to 764 mg/kg. Considering the high content of essential elements in CSSs that are useful for daily human needs, the potential use of CSS should be encouraged. On the other hand, in order to meet the requirements for the use of novel foods, monitoring of potentially toxic elements must be carried out. [ABSTRACT FROM AUTHOR]

Coffee is one of the most highly valued, consumed and comercialized foods in the world. Due to its considerable importance, it has become the target of numerous adulterations. Detecting a possible adulteration and the presence of additional adulterants in coffee has become an issue of great concern mainly because the compounds used as adulterants exhibit physical features very similar to ground roasted coffee. Aiming to overcome these difficulties, this work reports the development and application of a relatively faster, highly effective and reliable method for the detection and identification of adulterations in roasted coffee through the analysis of the composition of the volatile fraction in the presence of adulterants such as rice, corn, soybeans and barley. The proposed method was based on gas chromatography coupled with mass spectrometry (GC–MS) and chemometric tools. The application of the method led to the exclusive identification of many compounds in the volatile fraction of the adulterants investigated. The adulterants, despite having compounds similar to coffee, differed in terms of their volatile profiles, and consisted mainly of hydrocarbons, aldehydes, esters and carboxylic acids. Among all the compounds identified, five compounds were found to be the main determinants of adulteration: 2-furanmethanol-acetate, 2-methoxy-4-vinylphenol, 5-methyl-2-furancarboxaldehyde, 2-furanmethanol and glycerol-1,2-diacetate. [ABSTRACT FROM AUTHOR]

Ethyl hydrocinnamate is an ester with a sweet, fruity, honey-like scent commonly used as a flavor and fragrance agent. Due to its chemical structure, it can be easily obtained through enzymatic reactions without the need for harsh substances and processes. This study investigated the immobilization of the commercial lipase Sustine® 131 onto spent coffee grounds (SCG) as a low-cost support for the enzymatic synthesis of ethyl hydrocinnamate. Spent coffee grounds underwent pretreatment with water, hexane, and ethanol to serve as a lipase adsorption platform and extract valuable bioactive compounds such as polyphenols. The immobilized lipase displayed both hydrolytic and synthetic activities during 12 weeks of storage at room temperature. The optimal reaction conditions for the synthesis of ethyl hydrocinnamate were determined using a Box–Behnken plan. It was shown that the enzyme concentration and the temperature were crucial for achieving high yields of ethyl hydrocinnamate with a conversion rate above 92%. Specifically, at least 18% enzyme concentration and a temperature of 45 °C were necessary. This eco-friendly approach utilized abundant food waste residue as an inexpensive and renewable immobilization support, enabling efficient biocatalytic production of the high-value flavor ester ethyl hydrocinnamate. [ABSTRACT FROM AUTHOR]

Spent coffee grounds (SCGs), a waste product of the coffee industry, present a significant untapped resource for fuel production. This study aims to optimize the gasification of SCG using various metal catalysts (NiO, MnO2, Al2O3, and Fe2O3) to maximize syngas yield. SCG samples were gasified at different temperatures (800 °C, 900 °C, 1000 °C) and analyzed using Scanning Electron Microscopy (SEM), Thermogravimetric Analysis (TG-DTA), and Fourier Transform Infrared (FTIR) spectroscopy to evaluate catalyst performance and reaction mechanisms. The findings indicated that utilizing mixing techniques for physical contact to introduce catalysts led to a uniform distribution of catalyst particles throughout the sample. The decomposition rate of the gasification experiment after adding the catalyst was 24% faster than that of the pure SCGs. In the gasification experiment, the MnO2 catalyst showed the highest CO production, which was 71% higher than that of NiO under the same conditions. At this temperature, MnO2 generated around 171% more CO than at 800 °C, surpassing the yields observed with other catalysts. The study concludes that Mn emerged as the most promising catalyst, significantly improving both CO and CH4 yields. Selecting the appropriate metal catalyst and optimizing operational temperatures are crucial for enhancing the efficiency of SCG gasification. [ABSTRACT FROM AUTHOR]

Escitalopram (ESC) is commonly prescribed as an antidepressant to enhance serotonin levels in the brain, effectively addressing conditions such as depression and anxiety. The COVID-19 pandemic, along with ongoing mental health crises, has exacerbated the prevalence of these disorders, largely due to factors such as social isolation, fear of the virus, and financial difficulties. This study presents the enhancement of a glassy carbon electrode (GC) through the incorporation of hydrochar (HDC) derived from spent coffee grounds and copper nanoparticles (CuNPs) for the detection of ESC in synthetic urine. Characterization of the nanocomposite was conducted using scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), and cyclic voltammetry (CV). The analytical parameters were systematically optimized, and a sensing platform was utilized for the quantification of ESC via square-wave voltammetry (SWV). The established linear range was found to be between 1.0 µmol L−1 and 50.0 µmol L−1, with a limit of detection (LOD) of 0.23 µmol L−1. Finally, an electrochemical sensor was employed to measure ESC levels in synthetic urine, yielding recovery rates ranging from 91.7% to 94.3%. Consequently, the HDC-CuNPs composite emerged as a promising, sustainable, and cost-effective alternative for electroanalytical applications. [ABSTRACT FROM AUTHOR]

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An actual scientific problem in current concrete science is poor knowledge of the problem of modifying concrete with plant waste. At the same time, plant waste benefits from other types of waste because it is a recycled raw material. A promising technological approach to modifying concrete with plant waste is the introduction of components based on the processing of coffee production waste into concrete. This study aims to investigate the use of biochar additives from spent coffee grounds (biochar spent coffee grounds—BSCG) in the technology of cement composites and to identify rational formulations. A biochar-modifying additive was produced from waste coffee grounds by heat treatment of these wastes and additional mechanical grinding after pyrolysis. The phase composition of the manufactured BSCG additive was determined, which is characterized by the presence of phases such as quartz, cristobalite, and amorphous carbon. The results showed that the use of BSCG increases the water demand for cement pastes and reduces the cone slump of concrete mixtures. Rational dosages of BSCG have been determined to improve the properties of cement pastes and concrete. As a result of the tests, it was determined that the ideal situation is for the BSCG ratio to be at a maximum of 8% in the concrete and not to exceed this rate. For cement pastes, the most effective BSCG content was 3% for concrete (3%–4%). The compressive and flexural strengths of the cement pastes were 6.06% and 6.32%, respectively. Concrete's compressive strength increased by 5.85%, and water absorption decreased by 6.58%. The obtained results prove the feasibility of using BSCG in cement composite technology to reduce cement consumption and solve the environmental problem of recycling plant waste. [ABSTRACT FROM AUTHOR]

Coffee is a significant commodity trend, with numerous coffee shops rapidly established in Indonesia. The development of this industry has led to an increased discharge of coffee grounds into the environment. The discarded grounds contain oil which can be optimized using various methods and serve as a raw material for biodiesel. Therefore, this study aimed to compare the maceration and ultrasonic methods of extracting coffee grounds. The comparison focused on yield, mass transfer value (diffusivity), and extraction speed constant based on the proposed mathematical model. The results showed a yield of 12.1% and 16%, for the maceration and ultrasonic methods, respectively. Diffusivity value was registered at 9.99 x 10-11 m2/min and 9.8 x 10-10 m2/min, while extraction speed constant values were discovered to be 0.2 m/min and 1.798 m/min, respectively. Additionally, the energy evaluation of ultrasonic extraction produced a Gibbs energy value of -3765.72 Joules.

The immense popularity of coffee around the world generates significant amounts of coffee grounds. They are often improperly disposed of, which can have a negative impact on the environment. Due to their chemical composition and physical properties, coffee grounds are an excellent bioenergy material. This paper presents a study of the feasibility of using spent coffee grounds (CG) as an additive to pine sawdust (PS) pellets to improve their energy properties. The tests were carried out on samples of pellets consisting of 100% PS, 100% CG, and mixtures of 95% PS and 5% CG, 85% PS and 15% CG, and 70% PS and 30% CG. Physical and chemical analyses were carried out to determine the suitability of the obtained pellet as a biofuel in accordance with ISO 17225. Combustion tests were also carried out in a laboratory boiler to analyze flue gases and determine CO and NOx emissions in accordance with EN-303-5 for biomass boilers. The amount of emitted volatile organic compounds (VOCs) was also determined. Experimental results show that the addition of CG to PS reduces the durability of the pellets and increases CO and NOx emissions but increases their energy value and reduces the amount of VOC emissions. The requirements of both standards were fulfilled with a mixture of 95% PS and 5% CG. However, test results show that it is possible to add CG to PS in amounts up to 15%, although this will require additional research. [ABSTRACT FROM AUTHOR]

As an abundant commodity, coffee production generates significant scraps and by-products, increasing the potential pollution hazards. Circular economy and bioeconomy can help valorize Spent Coffee Grounds (SCGs), e.g., as fillers in polymer-based composites using conventional manufacturing, i.e., injection molding. Large-format additive manufacturing with pellet extruders offers a further option for new applications, reducing costs for the valorization of biomass waste. However, its use in this context remains unexplored, especially for applications with complex geometries or critical overhangs. This work investigates new biomass waste-based materials for large-format additive manufacturing with direct feeding extrusion, fabricating self-supported complex overhang geometries through nonplanar slicing. The thermal, rheological, and mechanical properties of three novel polymer-based pellet compounds with post-industrial SCGs, i.e., injection molding grade polylactic acid/SCGs, recycled low-density polyethylene/SCGs, and high-density polyethylene/SCGs, were herein investigated to evaluate their printability, defining their extrusion temperatures (190 °C and 170 °C). Results showed suitable viscosity ranges (133.6–839.7 Pa∙s) and accurate tensile values comparable with literature, e.g., ~ 1–3% minimum relative standard deviations (polylactic acid/SCGs), or conventional manufacturing, e.g., elastic moduli of 107.4 MPa (recycled low-density polyethylene/SCGs) and 587 MPa (high-density polyethylene/SCGs). Their use with large-format 3D printers was assessed thanks to nonplanar samples with complex overhang geometries, reaching a maximum curvature angle of 32° and fabricating overhangs up to 25° without supports. According to the tests, especially polylactic acid/SCGs, a bio-based compound, and recycled low-density polyethylene/SCGs, a fully recycled material, can be used for large-format 3D printing applications with complex geometries, e.g., furniture, interior, and exhibition design. This work paves the way for new materials for large-format additive manufacturing, reducing the need for 3D printing grade feedstock, cutting costs and consumption from filament processing, and fostering material waste reduction practices. [ABSTRACT FROM AUTHOR]

Summary: Second-stage juveniles (J2) of Meloidogyne species are known to be repelled by several compounds. Although such repellents could serve for nematode control, effective, practical and sustainable repellents are unknown. The present study tested instant coffee crystals (ICC) and a methanolic extract of spent coffee grounds (SCG) for their repellency against, and infection inhibition of, J2 of Meloidogyne species on agar plate assays. J2 of Meloidogyne javanica , M. hapla and M. marylandi were repelled by the SCG extract and ICC. When ICC were mixed with chemical J2 attractants, their attractiveness to M. javanica J2 was reduced or abolished. ICC and the SCG extract deposited near lettuce seedling roots on the agar plate reduced the number of M. javanica , M. incognita , and M. hapla J2 attracted to the root tips by 84.3-96.4%, decreased infection rates by 37.5-75.0%, and increased root length 1.3- to 2.8-fold compared to seedlings grown on the non-treated side of the same plate. Thoroughly mixing the SCG extract into the plated agar reduced the number of J2 of the three species attracted to lettuce root tips by 46.7-98.6% and the infection rate by 87.5-95.8%, and increased the root length of the seedlings up to 2.8-fold, although no nematicidal effect was found. The same SCG-treated agar plate reduced the attraction of M. javanica J2 to a chemical attractant. The results suggest that ICC and the SCG extract have repellent and infection-inhibitory activity against Meloidogyne J2 and are potential control means for Meloidogyne species. [ABSTRACT FROM AUTHOR]