Unveiling the role of stratified extracellular polymeric substances in membrane-based microalgae harvesting: Thermodynamic and computational insights.

Membrane separation technology has emerged as a highly energy-efficient method for microalgae enrichment and harvesting in wastewater treatment. However, membrane fouling caused by algal cells and stratified extracellular polymeric substances (EPS) remains a critical barrier to its industrial-scale application. This study meticulously investigates the micro process of algae-derived pollutants stacking to the membrane surface affected by stratified EPS.

A Novel Shear-Detachment Approach for Modeling Dynamics of Membrane Cleaning.

We report a novel shear-detachment (SD) approach to simulate the dynamics of flux recovery in the membrane cleaning process. In this model, the rate of foulant detachment away from the membrane is governed by both the shear intensity and the probability of successful foulant detachment, with the latter modeled by Boltzmann distribution. Our SD predictions exhibit good agreement with experimental results, accurately capturing the dynamics of flux recovery.

Hemicellulose-derived porous spherical micron-cage for advanced Zn storage.

Zinc ion capacitor (ZIC) is regarded as a new generation of energy storage device because of high redox potential of zinc anode, eco-friendly and safety. Herein, using hemicellulose as precursor and self-made cubic CaCO as template, the porous carbon spherical micron-cage (MCs) were prepared by template method assisted physical activation method. The prepared MCs are mainly rich in mesopores and micropores.

Advances in sustainable nano-biochar: precursors, synthesis methods and applications.

Nano-biochar, characterized by its environmentally friendly nature and unique nanostructure, offers a promising avenue for sustainable carbon materials. With its small particle size, large specific surface area, abundant functional groups and tunable pore structure, nano-biochar stands out due to its distinct physical and chemical properties compared to conventional biochar. This paper aims to provide an in-depth exploration of nano-biochar, covering its sources, transformation mechanisms, properties, applications, and areas requiring further research.

Biochar applications for treating potentially toxic elements (PTEs) contaminated soils and water: a review.

Environmental pollution with potentially toxic elements (PTEs) has become one of the critical and pressing issues worldwide. Although these pollutants occur naturally in the environment, their concentrations are continuously increasing, probably as a consequence of anthropic activities. They are very toxic even at very low concentrations and hence cause undesirable ecological impacts.

Progress in electrocatalytic hydrogen evolution of transition metal alloys: synthesis, structure, and mechanism analysis.

At present, the problems of high energy consumption and low efficiency in electrocatalytic hydrogen production have limited the large-scale industrial application of this technology. Constructing effective catalysts has become the way to solve these problems. Transition metal alloys have been proved to be very promising materials in hydrogen evaluation reaction (HER).

Technologies for pollutant removal and resource recovery from blackwater: a review.

Blackwater (BW), consisting of feces, urine, flushing water and toilet paper, makes up an important portion of domestic wastewater. The improper disposal of BW may lead to environmental pollution and disease transmission, threatening the sustainable development of the world. Rich in nutrients and organic matter, BW could be treated for resource recovery and reuse through various approaches.

Pollution characteristics and health risks of heavy metals in road dust in Ma'anshan, China.

Road dust contains various heavy metals, which are re-suspension in the air under the action of wind and other external forces, threatening people's health all the time. Road dust was collected in the industrial heavy traffic area (IHT), non-industrial heavy traffic area (HT), urban area (UA), and study recreation area (SR) of Ma'anshan. The pollution degree of heavy metals in the four areas was calculated and demonstrated IHT > HT > UA > SR.

New insight in algal cell adhesion and cake layer evolution in algal-related membrane processes: Size-fractioned particles, initial foulant seeds and EDEM simulation.

A clear understanding of algal cell adhesion and cake layer evolution in algal-related membrane processes (ARMPs) is urgently required to mitigate the membrane fouling. In this study, the effect of microparticles (10 μm-30 μm), subvisible particles (0.45 μm-10 μm), and ultrafine particles (50 kDa-0.

Microalgal wastewater recycling: Suitability of harvesting methods and influence on growth mechanisms.

Wastewater recycling helps address the challenge of microalgae biomass commercialization by allowing for efficient resource recovery. In this study, three conventional harvesting methods, including centrifugation, microfiltration, and flocculation sedimentation, were investigated to explore the effects of harvesting methods on the characteristics of recycled wastewater and the growth of microalgae to select a suitable harvesting method for the microalgal wastewater recycling system. During the wastewater recycling process, the least amount of accumulated substances was exhibited in the wastewater recycled by microfiltration, followed by centrifugation, and the most by flocculation sedimentation.

Biogenic synthesis of reduced graphene oxide decorated with silver nanoparticles (rGO/Ag NPs) using table olive (olea europaea) for efficient and rapid catalytic reduction of organic pollutants.

In this work, graphene oxide (GO) sheets were prepared via a facile electrochemical exfoliation of graphite in acidic medium and subsequent oxidation with potassium permanganate. The GO sheets were employed for preparation of reduced GO adorned with nanosized silver (rGO/Ag NPs) using green reduction of GO and Ag(I) via olive fruit extract as a reducing and immobilizing agent. The crystal phase, morphology, and nanostructure of the prepared catalyst were characterized by XRD, SEM, EDX, UV-Vis and Raman spectroscopy techniques.

PAC-UF Process Improving Surface Water Treatment: PAC Effects and Membrane Fouling Mechanism.

In this study, the water purification effect and membrane fouling mechanism of two powdered activated carbons (L carbon and S carbon) enhancing Polyvinylidene Fluoride (PVDF) ultrafiltration (UF) membranes for surface water treatment were investigated. The results indicated that PAC could effectively enhance membrane filtration performance. With PAC addition, organic removal was greatly enhanced compared with direct UF filtration, especially for small molecules, i.

Effect of Ammonia on Laminar Combustion Characteristics of Methane-Air Flames at Elevated Pressures.

In this paper, laminar combustion characteristics of methane/ammonia/air flames are numerically investigated using the Chemkin/Premix code. The initial temperature is set as 298 K; the initial pressures are set as 1, 2, 5, 10, and 20 atm; and the equivalence ratios are set as 0.8-1.

A promising microalgal wastewater cyclic cultivation technology: Dynamic simulations, economic viability, and environmental suitability.

The microalgal wastewater cyclic cultivation technology (AWCT) proposed in this study helps address the challenges surrounding water scarcity and ecological sustainability in a clean, resource-efficient, and affordable manner. A novel microalgae growth model (AGM) elucidating the growth mechanisms of microalgae in the AWCT system was established for dynamic simulations and design optimization. The recycled wastewater accelerated the growth rate of microalgae, and increased biomass and lipids content by 11% and 37.

Evaluation of the performance of different membrane materials for microalgae cultivation on attached biofilm reactors.

Attached microalgae production in wastewater is a promising method to further develop biofilm reactors by reducing economic costs associated with biomass separation and harvesting. However, the reliability of materials to support such adherence needs further investigation. Five common microfiltration membranes were evaluated in this study to assess their influence on the efficacy of harvesting .

Diatomite Dynamic Membrane Fouling Behaviour during Dewatering of in Aquaculture Wastewater.

Combined microalgal and membrane filtration could effectively treat aquaculture wastewater; however, the membrane fouling induced by extracellular organic matter (EOM) during the dewatering process is an issue. This study investigated diatomite dynamic membrane (DDM) fouling behaviour during the dewatering of under the influence of copper ions. The results indicate that copper ion heavy metals in aquaculture wastewater significantly affected purification and algae dewatering by DDM.

Application of Coagulation-Membrane Rotation to Improve Ultrafiltration Performance in Drinking Water Treatment.

The combination of conventional and advanced water treatment is now widely used in drinking water treatment. However, membrane fouling is still the main obstacle to extend its application. In this study, the impact of the combination of coagulation and ultrafiltration (UF) membrane rotation on both fouling control and organic removal of macro (sodium alginate, SA) and micro organic matters (tannic acid, TA) was studied comprehensively to evaluate its applicability in drinking water treatment.

Natural organic matter separation by forward osmosis: Performance and mechanisms.

The purification performance of a forward osmosis (FO) membrane on natural organic matter (NOM) contained in real surface water by was investigated systematically. FO could reject the natural dissolved organic matter (DOM) effectively with removal efficiencies of approximately 99.0%.

Remarkable phosphate recovery from wastewater by a novel Ca/Fe composite: Synergistic effects of crystal structure and abundant oxygen-vacancies.

Calcium-based materials are considered to be promising adsorbents for phosphate removal in the water environment due to their environmental friendliness and low price. However, improving the efficiency and rate of P adsorption of calcium-based materials still needs further exploration. In this study, a high-efficiency and eco-friendly Ca/Fe composite was rationally designed and fabricated by a co-precipitated method.

Unraveling the Overlooked Involvement of High-Valent Cobalt-Oxo Species Generated from the Cobalt(II)-Activated Peroxymonosulfate Process.

Sulfate radical (SO) is widely recognized as the predominant species generated from the cobalt(II)-activated peroxymonosulfate (PMS) process. However, in this study, it was surprisingly found that methyl phenyl sulfoxide (PMSO) was readily oxidized to the corresponding sulfone (PMSO) with a transformation ratio of ∼100% under acidic conditions, which strongly implied the generation of high-valent cobalt-oxo species [Co(IV)] instead of SO in the Co(II)/PMS process. Scavenging experiments using methanol (MeOH), -butyl alcohol, and dimethyl sulfoxide further suggested the negligible role of SO and hydroxyl radical (OH) but favored the generation of Co(IV).

Can flow-electrode capacitive deionization become a new in-situ soil remediation technology for heavy metal removal?

In this study, we present a novel soil electrochemical remediation technology (called S-FCDI), which is based on flow-electrode capacitive deionization (FCDI), for Cd removal from kaolin while under continuous operation mode. The results demonstrated that Cd can be effectively removed from kaolin with reasonable energy consumption and minimal macroelement loss. The carboxylic (OOH) functional groups on the surface of activated carbon (AC) facilitated the transfer of Cd from kaolin onto carbon surface.

Removal of ofloxacin with biofuel production by oleaginous microalgae Scenedesmus obliquus.

Microalgae-based technology is an environmental-friendly and cost-effective method for biofuel production and pollutants removal. In this study, Scenedesmus obliquus (S. obliquus) was cultured with varying concentrations of ofloxacin (OFL) in BG11 medium.

Intelligent mitigation of fouling by means of membrane vibration for algae separation: Dynamics model, comprehensive evaluation, and critical vibration frequency.

Vibration membrane filtration has been confirmed as an effective method to improve algae separation from water. However, the fouling evolution process and the antifouling mechanism are not well understood. In this study, a novel hybrid method based on a dynamics model was proposed, a comprehensive evaluation was conducted, and the critical vibration frequency for accurate analysis and prediction of membrane fouling was developed.