Anion exchange membrane fouling in electrodialysis: Mechanistic insights from organic matter fractionation

Effect of organic amendments on soil organic carbon fractions, water retention, and mechanical properties in a Chinese Alfisol

Soil organic carbon fractions influenced by organic input diversity and tillage frequency after 25 years in Mid-Atlantic US grain cropping systems

Aggression and depletion of residual organic phase in contaminated porous media: In-situ microemulsification approach.

Ultrasound treatment of digested sludge: process parameters interaction and comparative assessment of batch and flow-through configurations.

Fast pyrolysis is an established and efficient technology for converting biomass into liquid products, but the resulting bio-oil is a complex and reactive mixture, requiring additional refinement steps to make its use viable. Developing an effective technique is crucial for extracting valuable chemicals. Fractional condensation (FC) is a promising online separation method that acts directly on hot pyrolysis vapors, reducing energy consumption. This research reviews FC, evaluating its parameters and equipment. The process consists of a series of condensers with decreasing temperatures, which allow the separation of components based on their dew points. Temperature control is the most important parameter, dictating the selectivity and composition of the obtained fractions. The results demonstrate that FC is effective in obtaining more stable and usable fractions. It was possible to identify organic fractions with significantly reduced water content and high calorific value, in addition to the removal of carboxylic acids in the low-temperature stages, improving stability and mitigating corrosion. Phenol-rich fractions can also be obtained, reinforcing the potential of pyrolysis as a biorefinery platform. However, challenges remain, such as the need for precise temperature control and the impact of non-condensable gases (NCGs). Future research should focus on optimizing composition control, modeling the effects of NCGs, and maximizing the extraction of valuable chemicals on an industrial scale. These advances could solidify CF as a key step toward the efficient and sustainable use of bio-oil in energy and chemical applications.

Municipal solid waste (MSW) management in Brazil faces significant challenges related to waste segregation, collection efficiency, and environmentally adequate disposal. This study quantifies the carbon emissions associated with organic solid waste management, from 2022 to 2034, in the city of João Pessoa (Northeast Brazil). To this end, the Life Cycle Assessment methodology is applied to two scenarios: Scenario 1 (where all organic fraction is landfilled) and Scenario 2 (progressive implementation of composting for the domestic organic waste, starting in 2023, with increases each year until reaching 50% in 2034, and the remainder being landfilled). The latter is proposed based on the targets established in the Municipal Solid Waste Plan of João Pessoa. Projection for MSW considered a per capita rate of 0.86 kg/inhab.day, combined with a population growth rate of 1.92%/year. The results indicate that Scenario 1 emits 825 Mt CO2-eq while Scenario 2 emits 704 Mt CO2-eq for the study period (a reduction of 15%). A sensitivity analysis examined the effects of increasing transport distance (25–45 km) and the organic fraction of MSW (35–45%) on GHG emissions. Although total emissions rose under both conditions, the comparative environmental advantage of composting over landfilling remained stable. These results confirm the robustness of the analysis and reinforce composting as a low-carbon, effective strategy for managing urban waste.

This study explores approaches to overcome mass transport limitations in organic electrosynthesis, which present significant challenges for industrial implementation. We first investigated convection-enhanced mass transport, demonstrating that the Sherwood number effectively characterizes mass transport conditions regardless of the convection mechanism. Our results showed that forced liquid convection and bubble-induced convection produce equivalent electrochemical performance when operating at the same Sherwood number, providing a unified framework for scaling and predicting reactor performance. Building on this foundation, we subsequently examined a complementary strategy: increasing bulk organic concentration beyond solubility limits to create multiphase systems. Using adiponitrile production as a model system, we developed an experimental flow reactor to systematically investigate how organic phase distribution affects reaction outcomes. Our findings reveal that strategic manipulation of the organic phase fraction dramatically improves reaction selectivity, with Faradaic efficiency towards adiponitrile increasing from less than 50% to over 80% at high current densities when acrylonitrile fraction surpasses the solubility limit. However, higher organic concentrations also shift the product distribution, creating a critical balance between desired product selectivity and competing side reactions. We seek to identify optimal operating regimes with respect to hydrodynamics (interelectrode spacing, flow rate, organic loading) that affect critical performance metrics including selectivity, production rate, and energy efficiency. These sequential investigations provide complementary approaches to addressing mass transport challenges in organic electrosynthesis, offering a comprehensive framework for optimizing electrochemical systems for sustainable chemical manufacturing.

ABSTRACT This study investigates the effects of ozone pretreatment on the filtration performance and fouling behavior of ceramic membranes (7-channel tubular membrane, molecular weight cutoff: 1 kDa). Three types of feed solutions were tested: humic acid solution (HA, dissolved organic carbon [DOC] = 4.0 mg/L), river water (RW, DOC = 4.7 mg/L), and secondary wastewater effluent (SE, DOC = 5.4 mg/L). HA exhibited a broad molecular-weight (MW) distribution with three peaks (550 Da, 1–6 kDa, and 100 kDa), RW showed a narrow range with a single peak at 650 Da, and SE displayed a broader distribution than RW with a distinct peak near 650 Da. Gel permeation chromatography and fluorescence excitation-emission matrix analyses confirmed that ozone pretreatment progressively degraded high MW organic constituents into low-MW molecules across all feed types. Natural organic matter fractionation showed a compositional shift from hydrophobic to more hydrophilic or transphilic fractions. In filtration experiments, HA exhibited increased flux decline with higher ozone dosages, likely due to the accumulation of hydrophilic substances that readily adsorb to the hydrophilic membrane surface. In contrast, ozone pretreatment improved flux performance for RW and SE by reducing concentrations of membrane-interactive hydrophilic species. Fouling model analysis based on combined mechanisms revealed that intensified fouling in HA was primarily driven by enhanced cake filtration. For RW and SE, the dominant fouling mechanism remained cake filtration, but its contribution decreased with ozone treatment due to the depletion of hydrophilic components. These results demonstrate that the effectiveness of ozone pretreatment in ceramic membrane filtration depends strongly on the molecular weight distribution and hydrophilic/hydrophobic character of dissolved organic matter.

This study presents the assembly of titania nanoplates (TNPs) into three‐dimensional supraparticles (SPs) via an emulsion‐based assembly technique using dodecyltrimethylammonium bromide (DTAB) as surfactant. The SPs have diameters ranging from ∼100 to ∼400 nm and are encapsulated within a polystyrene shell. The encapsulation is achieved through surface‐initiated photocatalyzed radical polymerization (UVP), utilizing the intrinsic photocatalytic activity of the TNPs. By varying the duration of UV light ( λ = 365 nm) exposure, the overall organic fraction of the polymer can be tuned. Small‐angle X‐ray scattering (SAXS) measurements indicate a higher degree of order within the SPs after the polymerization and increased interparticle distances between the encapsulated TNPs. Presumably, the polymerization initiates at the double bond of the native oleylamine ligands on the TNP surface, resulting in surface‐grafting of the polymer and re‐ordering of the TNPs within the encapsulated SPs. Furthermore, the functionalization of the polymer shell with carboxylic acid or azide groups is demonstrated. As a proof‐of‐concept, TNPs were assembled with superparamagnetic iron oxide nanocubes (SPIONs) to form hybrid SPs. The UVP could be easily adapted to these hybrid SPs, resulting in encapsulated TNP/SPION‐based SPs that combine the optical and magnetic properties of both materials.

TiO2 amendment accelerates low-temperature composting start-up.

Abstract Background and aims Cover crops are an important measure for carbon (C) sequestration in agriculture. However, little is known about the potential of cover crops to increase C under Nordic conditions and the efficiency of this measure over time. Here, we quantify the potential contribution of different cover crops to soil organic carbon (SOC) and organic matter fractions, and study how this is affected by the origin of the C input (aboveground or belowground residues). Methods We conducted a 13 CO 2 pulse-labelling experiment during the growing season of four cover crops adapted to Nordic conditions, representing different plant functional types. The assimilated 13 C was traced in soil during the following two years. We investigated the fate of cover crop C in two organic matter fractions, Particulate Organic Matter (POM) and Mineral-Associated Organic Matter (MAOM), known to have different persistence in soil. Results Carbon derived from aboveground residues decayed two to three times faster as compared to belowground C. Belowground C inputs were similar among cover crops despite their contrasting root traits and differences in root biomass C. Rhizodeposited-C was consistently the largest belowground C input. Cover crop species affected the quantity of POM-C and MAOM-C, but MAOM-C was preferentially formed from belowground C (ranging from 0.63 ± 0.2 to 0.25 ± 0.1 Mg MAOM-C ha −1 across different cover crops), regardless of the species. Conclusions Cover crop species that can combine large belowground biomass production with root traits that promote physical and physico-chemical protection of OM will contribute most effectively to the long-term SOC pool. These aspects need to be balanced with considerations related to agricultural management.

Japanese encephalitis virus (JEV) poses a significant public health risk due to the lack of effective antiviral therapies. To identify novel antiviral agents, we evaluated the antiviral activity of ethanol extracts and organic solvent fractions derived from the roots and stems of hemp (Cannabis sativa L.). Noncytotoxic concentrations of the extracts and fractions were determined using in vitro cytotoxicity assays. At these concentrations, several fractions demonstrated potent virucidal activity, with the hexane and chloroform fractions showing the strongest effects. Post-treatment of virus-infected cells with these fractions significantly suppressed viral replication, as evidenced by reduced JEV mRNA and E protein expression. In contrast, pre-treatment or co-treatment did not yield notable antiviral effects. GC-MS analysis revealed the presence of multiple known hemp-derived compounds in the active fractions. Among them, stigmasterol exhibited strong virucidal and antiviral activity. It inhibited viral entry and growth when applied during or after infection and significantly decreased viral mRNA and E protein levels in infected cells. These findings suggest that stigmasterol contributes to the antiviral effects of hemp extracts and may be one of the active compounds responsible for inhibiting JEV replication. This study highlights the potential of hemp-derived natural products, particularly stigmasterol, as promising candidates for the development of antiviral agents against JEV infection.

Valorization of municipal solid waste (MSW) for energy represents a strategic alternative for developing countries, as it mitigates emissions, reduces pressure on landfills, and diversifies the electricity matrix. This study quantified the potential for electricity generation from MSW in the Jequitinhonha Valley, Minas Gerais, Brazil, using primary gravimetric characterization data, a method rarely employed in tropical areas. The identified composition showed a predominance of the organic fraction (47.6–73.3%), confirming the relevance of biological routes. The results indicated a consolidated potential of 106,640 MWh·year−1, of which 94.7% was from biogas recovery and 5.3% from incineration. Almenara, one of the three locations analyzed, showed the highest potential (48,200 MWh·year−1), followed by Diamantina (34,540 MWh·year−1) and Capelinha (23,900 MWh·year−1). The specific yields ranged from 0.33 to 0.53 MWh·ton−1 MSW and the per capita indicators from 1.01 to 1.49 MWh·cap−1·year−1. The climate mitigation potential reached 1.0 Mt of CO2eq·year−1. It is concluded that valorization in the Jequitinhonha Valley should prioritize biogas recovery, complemented by the incineration of rejects. The materialization of this potential requires advancements in infrastructure, selective collection, and socio-productive inclusion. This study provides evidence for public policies and contributes to the literature by demonstrating that valorization can boost energy transition and socio-environmental equity in developing tropical regions.

Very persistent and very mobile (vPvM) substances threaten the environment and human health. These chemicals can persist in aquatic systems and move rapidly due to their affinity for water over soil or other adsorbents. Chemical mobility is usually classified using the organic carbon-water partition coefficient (Koc), but experimental log Koc data are unavailable for most substances. With thousands of new chemicals entering the market annually, there is a growing need for advanced cheminformatics tools to prioritize substances of concern. Because reversed-phase liquid chromatography (RPLC) data are more widely available, they were used here as a proxy for environmental mobility. The organic modifier fraction at elution was applied to assign mobility labels to 146,902 chemicals from an RPLC data set. For each chemical, 881 PubChem fingerprints were computed to capture structural information. A random forest classifier was then trained to predict mobility from retention behavior and fingerprints. The model achieved F1 scores of 0.87, 0.81, and 0.96 for very mobile, mobile, and nonmobile classes, respectively, in the test set. Applied to all REACH-registered chemicals (n = 64,492), the model classified 20% as very mobile, 26% as mobile, and 53% as nonmobile, providing a scalable tool for early identification of vPvM substances.

ABSTRACT While long‐term film mulching has consistently increased crop yields, it has also contributed to land degradation, prompting adjustments in straw returning rates. However, the responses of soil organic carbon (SOC) and structure to optimal straw returning rates are in need of a deeper understanding. Here, we examined the effects of soil structure, SOC dynamics, and maize productivity under long‐term film mulching with varying straw return rates (0, 6000, 12,000, and 18,000 kg ha −1 ) in semi‐arid farmland. The SOC and particulate organic carbon (POC) content both reduced after long‐term film mulching. The varying changes of soil aggregation processes caused by different straw returning rates, which in turn affect the distribution of soil aggregates, particularly the proportion of > 0.25 mm aggregates. The effects of different straw return rates on crop yield were mainly driven by changes in organic carbon pools (microbial biomass and dissolved organic carbon), resulting from nutrient inputs that stimulated microbial growth. Higher straw return rates have promoted the stratification of SOC and modified the proportional distribution of organic carbon fractions. These changes have directly and indirectly increased maize yield by 21% and economic benefits by 15%. Based on the total application of straw in dryland farming systems, increasing the straw application rate to 18,000 kg ha −1 resulted in a synergistic improvement in SOC content, soil structure and economic benefits.

Influence of bulk-phase acidity, organic fraction, and dissolved oxygen on the photosensitized renoxification of nitrate in NaNO3/humic acid mixtures

Long-term organic-inorganic fertilization promoted the microbial necromass carbon accumulation in particulate and mineral-associated organic matter fractions in paddy soil

Soil organic matter fractions in the topsoil and subsoil of woody crop systems: Impact of reduced tillage plus cover crops under rainfed semi-arid Mediterranean conditions

Bringing soil sulfur to the forefront: How long-term cropping impacts sulfur speciation in soil organic matter fractions