Efficiency and mechanism of enhanced norfloxacin removal using amorphous TiO-modified biochar.

Inadequate treatment of antibiotic-contaminated wastewater, including compounds such as norfloxacin (NOR), poses a substantial treat to both ecological safety and human well-being. An innovative approach was devised to address NOR pollution using amorphous TiO modified biochar (A-TiO/BC) prepared via sol-gel impregnation. The resultant had a commendably specific surface area of 131.

Detoxification of corn stover prehydrolysate by different biochars and its effect on lactic acid fermentation.

During the utilization of lignocellulosic biomass such as corn stover, many by-products are produced in the pretreatment process that can severely inhibit the activity of microbes in the fermentation step. To achieve efficient biomass conversion, detoxification is usually required before microbial fermentation. In this study, the prehydrolysate from dilute acid pretreatment of corn stover was used as a lactic acid fermentation substrate.

Enhanced Enzymatic Sugar Recovery of Dilute-Acid-Pretreated Corn Stover by Sodium Carbonate Deacetylation.

The prehydrolysate from dilute acid pretreatment of lignocellulosic feedstocks often contains inhibitory compounds that can seriously inhibit the subsequent enzymatic and fermentation processes. Acetic acid is one of the most representative toxic compounds. In this research, alkaline deacetylation of corn stover was carried out using sodium carbonate under mild conditions to selectively remove the acetyl groups of the biomass and reduce the toxicity of the prehydrolysate.

Hypoxic Preconditioning Modulates BDNF and Its Signaling through DNA Methylation to Promote Learning and Memory in Mice.

Hypoxic preconditioning (HPC) as an endogenous mechanism can resist hypoxia/ischemia injury and exhibit protective effects on neurological function including learning and memory. Although underlying molecular mechanisms remain unclear, HPC probably regulates the expression of protective molecules by modulating DNA methylation. Brain-derived neurotrophic factor (BDNF) activates its signaling upon binding to the tropomyosin-related kinase B (TrkB) receptor, which is involved in neuronal growth, differentiation, and synaptic plasticity.

Adsorption Mechanism of Amidoxime Collector on the Flotation of Lepidolite: Experiment and DFT Calculation.

Lepidolite is an important mineral resource of lithium. With the increase in awareness of low-carbon and green travel, the demand for lithium has increased dramatically. Therefore, how to increase the output of lithium has to turn into high precedence.

The atmospheric microplastics deposition contributes to microplastic pollution in urban waters.

Identifying and understanding the potential sources delivering microplastics into the urban water environment is imperative for microplastic pollution control. However, how atmospheric deposition contributes to microplastic pollution in the urban water environment is unclear. Therefore, this study investigated the contribution of atmospheric deposition to microplastic pollution in urban waters based on the analysis of the atmospheric deposition characteristics in the urban area.

Adsorption of Trisiloxane Surfactant for Selective Flotation of Scheelite from Calcite at Room Temperature.

The separation and enrichment of scheelite from calcite are hindered by the similar active Ca sites of scheelite and the calcite with calciferous gangue. Herein, a novel trisiloxane surfactant, -(2-aminoethyl)-3-aminopropyltrisiloxane (AATS), was first explored and synthesized and recommended as the collector for the flotation separation of scheelite from calcite. The micro-flotation and mixed binary mineral flotation tests showed that AATS had excellent collection performance for scheelite and high selectivity for calcite within a wide pH range.

Iron ore production using a new Gemini surfactant at 273 K.

Herein we present the use of a Gemini surfactant and reverse froth flotation to efficiently separate magnetite from quartz and produce iron ore at 273 K. This surfactant achieved an obviously superior flotation performance (TFe recovery increased by 48.18%), and the dosage of the Gemini surfactant was three times less than that of a conventional monomeric surfactant.

Recovery of wolframite from tungsten mine tailings by the combination of shaking table and flotation with a novel "crab" structure sebacoyl hydroxamic acid.

Tailings ponds for gangue mineral storage are widely recognized as a dangerous source of toxic minerals and heavy metal-bearing solution. Therefore, recovering valuable minerals and critical elements from tailings is an important means to protect the environment in an economic way. Wolframite tailings usually contain a considerable amount of tungsten resources, but the presence of high content of kaolinite sludge makes it very difficult to recycle wolframite.

Copper single-atom catalyst as a high-performance electrocatalyst for nitrate-ammonium conversion.

Electrocatalytic nitrate reduction reaction (NORR), as a promising alternative to the Haber-Bosh process, provides new opportunities for ammonia (NH) production from the environmental and energy viewpoint. However, the NH yield rate and selectivity for NORR are still limited due to the lack of efficient electrocatalysts. Herein, we demonstrate an active and selective copper single-atom catalyst (Cu-N-C) for nitrate reduction to NH.

Medium-chain fatty acids production from carbohydrates-rich wastewater through two-stage yeast biofilm processes without external electron donor addition: Biofilm development and pH impact.

The production of medium-chain fatty acids (MCFAs) is considered promising for carbon resource recovery from waste streams. However, a large quantity of external electron donors are often required, causing great cost and environmental impact. Therefore, in this study, a two-stage technology was developed to produce MCFAs from carbohydrate-rich wastewater without external electron donor addition, with the biofilm development and pH impact being explored.

A comparative review of microplastics in lake systems from different countries and regions.

Microplastics, as defined here as plastics with a diameter of <5 mm, can impose severely detrimental impacts on the environment and can now be commonly found in different water bodies. To date, the status of microplastics in limnic systems, which have different hydrologic systems compared to other water bodies such as oceans or rivers, has rarely been reviewed. In the present study, the microplastic pollutants in different countries and regions were comparatively investigated in terms of their abundances, morphologies, and polymer types in the water and sediments of lakes.

Mechanistic study on calcium ion diffusion into fayalite: A step toward sustainable management of copper slag.

Copper slag, which contains Fe-rich fayalite (FeSiO), is a valuable solid waste that warrants further research in order to recover iron. Calcium oxide (CaO) can significantly enhance iron recovery from copper slag; however, the associated mechanism has not yet been explored. In this study, we investigated the interaction between CaO and FeSiO to obtain detailed understanding of the role of CaO in enhancing iron recovery.

Understanding the mobility and retention of uranium and its daughter products.

Knowledge of the behavior of technologically enhanced naturally occurring radioactive materials derived through the decay of U and its daughter products, and their subsequent fractionation, mobilization and retention, is essential to develop effective mitigation strategies and long-term radiological risk prediction. In the present study, multiple state-of-the-art, spatially resolved micro-analytical characterization techniques were combined to systematically track the liberation and migration of radionuclides (RN) from U-bearing phases in an Olympic Dam Cu flotation concentrate following sulfuric-acid-leach processing. The results highlighted the progressive dissolution of U-bearing minerals (mainly uraninite) leading to the release, disequilibrium and ultimately upgrade of daughter RN from the parent U.

"Umbrella" Structure Trisiloxane Surfactant: Synthesis and Application for Reverse Flotation of Phosphorite Ore in Phosphate Fertilizer Production.

Phosphorite is generally used in the manufacture of phosphate fertilizer and plays a vital role in the development of agricultural and food production. Nonetheless, how to obtain phosphorite concentrates efficiently and sustainably has become an urgent problem. In this study, a newly designed trisiloxane surfactant, -(2-Aminoethyl)-3-aminopropyltrisiloxane (AATS), has been prepared and utilized as an emerging collector for reverse flotation of phosphorite ore.

Specific ion binding interactions in potash flotation.

As the main resource of potash fertilizer, high grade of sylvite (KCl) is mainly separated from halite (NaCl) in soluble potash ores using flotation. An effective flotation collector determines the separation efficiency of sylvite. However, the collector adsorption mechanism is still the subject of much debate due to high ions concentration in the flotation pulp.

Poly(diallyldimethylammonium-MoS) based amorphous molybdenum sulphide composite for selectively mercury uptake from wastewater across a large pH region.

Amorphous molybdenum sulphide materials are attracting more attention in heterogeneous catalysis, gas adsorption and water remediation fields. Herein, a new type of amorphous molybdenum sulphide composite (poly(diallyldimethylammonium-MoS), shorten as PDADMA-MoS) was synthesized via a facile precipitation reaction. Metal adsorption tests of prepared PDADMA-MoS composite shows that Hg and Pb concentrations in solution can decrease from 10 ppm to <0.

Remarkable reusability of magnetic FeO-encapsulated CNS polymer/reduced graphene oxide composite: A highly effective adsorbent for Pb and Hg ions.

Magnetic FeO-encapsulated CNS polymer/reduced graphene oxide composite (rGO-poly(CNS)/FeO) was synthesized to remove Pb(II) and Hg(II) from aqueous solutions. This material was characterized by X-ray Photoelectron Spectroscopy, transmission electron microscopy, Fourier-transform infrared spectroscopy, X-ray powder diffraction, N adsorption, etc. The results suggest that final composite exhibits two-dimensional (2D) nanosheet structure, in which FeO nanoparticles or clusters are encapsulated between the layers of rGO-poly(CNS) matrix, preventing composite aggregation and nanoparticle detachment.

Engineering SrCuO composition to tailor the degradation activity toward organic pollutant under dark ambient conditions.

The composition of SrCuO mixed metal oxides (MMOs) was engineered via varying the amount of copper relative to strontium. As-synthesized SrCuO were highly active for degrading methyl orange (MO) pollutant at dark ambient conditions without the aid of other reagents. The catalytic activity of SrCuO demonstrated a reverse-volcano relationship with copper content.

Investigation on synthesis of ion-imprinted mesoporous adsorbents by using ultrasound- and microwave-assisted preparation and their dynamic adsorption properties on heavy metals.

Removal of the heavy metal ions in aqueous solution is an important technology for waste water treatment. The effects of using ultrasonic and microwave on synthesizing Pb, Zn, and Cu imprinted mesoporous adsorbents (Pb-IMA-UM, Zn-IMA-UM, and Cu-IMA-UM) and their dynamic adsorption properties were studied. The microstructure and composition of the ion-imprinted mesoporous adsorbents were discussed in detail by TEM, FTIR, N adsorption-desorption, XRD, and EDS.

Gemini surfactant: A novel flotation collector for harvesting of microalgae by froth flotation.

Froth flotation has been proved to be a promising approach for commercial scale harvesting of microalgae. However, all the surfactants used in the microalgae flotation harvesting process are conventional monomeric surfactants contain a single similar hydrophobic group in the molecule, which results in a low harvesting efficiency. In this work, a novel Gemini surfactant, N,N'-bis(cetyldimethyl)-1,4-butane diammonium dibromide (BCBD) was prepared, and originally recommended as a collector for froth flotation harvesting of Chlorella vulgaris from culture medium.

Morpholine-Based Gemini Surfactant: Synthesis and Its Application for Reverse Froth Flotation of Carnallite Ore in Potassium Fertilizer Production.

Potassium fertilizer plays a critical role in increasing the food production. Carnallite is concentrated by reverse froth flotation and used as a raw material to produce potassium fertilizer (KCl) in agriculture. However, all the surfactants used in the carnallite reverse flotation process are conventional monomeric surfactants contain a single similar hydrophobic group in the molecule, which results in a low production efficiency.

Magnetic dithiocarbamate functionalized reduced graphene oxide for the removal of Cu(II), Cd(II), Pb(II), and Hg(II) ions from aqueous solution: Synthesis, adsorption, and regeneration.

In this study, dithiocarbamate(DTC)-modified magnetic reduce graphene oxide (rGO-PDTC/FeO) was synthesized for the removal of heavy metal ions (Cu(II), Cd(II), Pb(II), and Hg(II)) in synthetic waste water. The rGO-PDTC/FeO nanocomposite was prepared via a novel synthesis route that includes GO bromination, nucleophilic substitution of polyethylenimine (PEI), the reaction with carbon disulphide (CS) and FeO nanoparticle loading. The prepared rGO-PDTC/FeO nanocomposite was characterised by XPS, FTIR, TEM and XRD, suggesting that DTC functional groups were chemically bonded to rGO surfaces.

Synthesis of a novel silica-supported dithiocarbamate adsorbent and its properties for the removal of heavy metal ions.

Silica-supported dithiocarbamate adsorbent (Si-DTC) was synthesized by anchoring the chelating agent of macromolecular dithiocarbamate (MDTC) to the chloro-functionalized silica matrix (SiCl), as a new adsorbent for adsorption of Pb(II), Cd(II), Cu(II) and Hg(II) from aqueous solution. The surface characterization was performed by FT-IR, XPS, SEM and elemental analysis indicating that the modification of the silica surface was successfully performed. The effects of media pH, adsorption time, initial metal ion concentration and adsorption temperature on adsorption capacity of the adsorbent had been investigated.