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distillation; drainage; electrolytes; geothermal energy; heat; heavy metals; hydrophobicity; iron oxyhydroxides; methodology; minerals; models; oxidation; pH; rivers; sulfates; temperature; vapors; wastewater; water quality; United States
Abstract:
... Acid rock drainage (ARD) is a metal-rich wastewater that forms upon oxidation of sulfidic minerals. Although ARD impacts >12,000 miles of rivers in the U.S. and has an estimated cleanup cost of $32–$72 billion, the low pH and high metal concentrations in ARD make rapid, high volume treatment without chemical addition difficult. This research focuses on a novel method of ARD treatment, membrane dis ...
... The increased production of carbon dots (CDs) and the release and accumulation of CDs in both surface and groundwater has resulted in the increasing interest in their research. To assess the environmental behavior of CDs, the interaction between CDs and goethite was studied under different environmental conditions. Electrokinetic characterization of CDs suggested that the ζ-potential and size dist ...
... The cooperative effects of pH and electrolytes on the aggregation of GQDs and the aggregate morphologies are characterized. Because GQDs have an average size of 9 nm with abundant O-functionalized edges, their suspension was very stable even in a high electrolyte concentration and low pH solution. Divalent cations (Mg²⁺ and Ca²⁺) excelled at aggregating the GQD nanoplates, while monovalent cations ...
... Soot produced during incomplete combustion consists mainly of carbonaceous nanoparticles (NPs) with severe adverse environmental and health effects, and its environmental fate and transport are largely controlled by aggregation. In this study, we examined the aggregation behavior for diesel soot NPs under aqueous condition in an effort to elucidate the fundamental processes that govern soot partic ...
... The problems of antibiotic overuse compel us to seek alternative antibacterial agents. Some clays have been shown to kill antibiotic-resistant human pathogens and may provide an alternative to known antibiotics. Here we show that Al toxicity plays a central role in the antibacterial action of a kaolin-rich clay from the Colombian Amazon (AMZ). Antibacterial susceptibility testing shows minimum inh ...
antibiotics; average daily intake; bioaccumulation; biotransformation; fluoroquinolones; food webs; human health; humans; hydrophobicity; invertebrates; macrolides; pH; pelagic fish; pollution; risk; risk management; trimethoprim; China
Abstract:
... Little information is available about the bioaccumulation and biomagnification of antibiotics in marine food webs. Here, we investigate the levels and trophic transfer of 9 sulfonamide (SA), 5 fluoroquinolone (FQ), and 4 macrolide (ML) antibiotics, as well as trimethoprim in nine invertebrate and ten fish species collected from a marine food web in Laizhou Bay, North China in 2014 and 2015. All th ...
... Jarosite can be an important scavenger for arsenic (As) and antimony (Sb) in acid mine drainage (AMD) and acid sulfate soil (ASS) environments. When subjected to reducing conditions, jarosite may undergo reductive dissolution, thereby releasing As, Sb, and Fe²⁺ coincident with a rise in pH. These conditions can also trigger the Fe²⁺-induced transformation of jarosite to more stable Fe(III) mineral ...
acidification; alum; aluminum; carbon; centrifugation; chemical oxygen demand; coagulants; coagulation; cost analysis; hydrochloric acid; magnesium ammonium phosphate; municipal wastewater; nitrogen content; pH; phosphorus; sludge; solubilization; sulfuric acid; total suspended solids
Abstract:
... In this work, recovery of aluminum from coagulated primary sludge and its reuse potential as secondary coagulant were investigated. The recovery process consisted of releasing the particle-bound aluminum from primary sludge by acidification (HCl or H₂SO₄), followed by separation using centrifugation for dissolved coagulant recovery. The recovered coagulant was then reused for treating primary wast ...
... Among the many uncertainties presented by poorly studied pathogens is possible transmission via human fecal material or wastewaters. Such worries were a documented concern during the 2013 Ebola outbreak in West Africa. Using published experimental data on virus inactivation rates in wastewater and similar matrices, we extracted data to construct a model predicting the T90 (1 × log₁₀ inactivation m ...
... The main psychoactive compound in marijuana, Δ⁹-tetrahydrocannabinol (THC), and its metabolites are emerging organic contaminants that have been detected in waste and surface waters. As legalization of marijuana for medical and recreational use continues, the effects of increased use and potency of marijuana on water and wastewater treatment processes and the environment should be considered. This ...
... Although emerging contaminants rarely exist individually in environmental contaminated systems, only limited information on their adsorption mechanisms in multicomponent solutions is currently available. To address this shortcoming, this work examines for the first time the accuracy of a surface complexation model in predicting the cooperative adsorption of nalidixic acid (NA) and niflumic acid (N ...
... Iron oxides are ubiquitous in soils and sediments and play a critical role in the geochemical distribution of trace elements and heavy metals via adsorption and coprecipitation. The presence of organic acids may potentially alter how metals associate with iron oxide minerals through a series of cooperative or competitive processes: solution complexation, ternary surface complexation, and surface s ...
... Although the electron selectivity (ES) of zerovalent iron (ZVI) for target contaminant and its utilization ratio (UR) decide the removal capacity of ZVI, little effort has been made to improve them. Taking selenate [Se(VI)] as a target contaminant, this study investigated the coupled influence of aeration gas and Fe(II) on the ES and UR of ZVI. Oxygen was necessary for effective removal of Se(VI) ...
... A high-efficient, low-cost, and eco-friendly catalyst is highly desired to activate peroxides for environmental remediation. Due to the potential synergistic effect between bimetallic oxides’ two different metal cations, these oxides exhibit superior performance in the catalytic activation of peroxymonosulfate (PMS). In this work, novel Mn₁.₈Fe₁.₂O₄ nanospheres were synthesized and used to activat ...
... To investigate the influence of hydration forces on the protein fouling of membranes and the major influence factors of hydration forces during the ultrafiltration process, bovine serum albumin (BSA) was chosen as model foulant. For various pH levels and hydrated ion and membrane species, the membrane–BSA and BSA–BSA interaction forces, and fouling experiments with BSA, as a function of ionic stre ...
... Disinfection is an indispensable process in wastewater treatment plants. New bacterial inactivation technologies are of increasing interest and persistent demand. A category of simple and efficient bactericidal systems have been established in this study, that is, the combination of divalent transition metal (Mn(II), Co(II), Fe(II), or Cu(II)) and sulfite. In these systems, metal catalyzed auto-ox ...
... The role of transition metals in the formation and aging of secondary organic aerosol (SOA) from aliphatic and aromatic precursors in heterogeneous/multiphase reactions is not well understood. The reactivity of soluble Fe(III) toward known benzene photooxidation products that include fumaric (trans-butenedioic) and muconic (trans,trans-2,4-hexadienedioic) acids was investigated. Efficient formatio ...
... ⁹⁹Tc is one of the most problematic radioisotopes in used nuclear fuel owing to its combined features of high fission yield, long half-life, and high environmental mobility. There are only a handful of functional materials that can remove TcO₄– anion from aqueous solution and identifying for new, stable materials with high anion-exchange capacities, fast kinetics, and good selectivity remains a ch ...
... Phosphorus (P) is an essential nutrient for living organisms and cannot be replaced or substituted. In this paper, we present a simple yet efficient membrane free electrochemical system for P removal and recovery as calcium phosphate (CaP). This method relies on in situ formation of hydroxide ions by electro mediated water reduction at a titanium cathode surface. The in situ raised pH at the catho ...
... The specific Eh–pH conditions and mechanism(s) for the reduction of arsenite, As(III), by pyrite are incompletely understood. A fundamental question is what role the pyrite surface plays in the reduction process. We used electrochemical methods to evaluate the reduction of As(III) under controlled redox conditions. As(III) reduction to elemental As(0) occurs on the pyrite surface under suboxic-red ...