The treatment of slaughterhouse wastewater was investigated by both acid precipitations and by oxidation processes. Precipitation tests were developed using three acids (HSO, HCl and HNO) at different operating pH (1-6). A decrease of the precipitation pH led to an increase of the conductivity values of the supernatant. Precipitation processes allowed the removal of chemical oxygen demand (COD) (41-97%), turbidity (56-99%) and total phosphorus (27-56%). Total phenols were removed (15-96%) from pH ≥ 2, depending on the precipitation process. Generally, precipitation processes decreased the hydroxide and bicarbonates species. Additionally, three different oxidation processes were tested at different concentrations (1-15 g L): Ca(ClO)₂, HO and CaO₂. When Ca(ClO)₂ and CaO₂ were applied, an increase of the supernatant conductivity was achieved. COD removal ≥71% and turbidity elimination in the range of 85-100% were achieved by using oxidation processes. CaO₂ was very effective to remove total phosphorus (81-96%). The increase of the oxidant concentration in HO and Ca(ClO)₂ oxidation processes led to a decrease in the removal of total phenols and bicarbonates species. Optical density of the microorganism cultures was efficiently eliminated (up to 100%) by oxidation processes. In addition, acid precipitation and oxidation allowed to remove total solids (TS), total volatile solids (TVS), total suspended solids (TSS), ammonia nitrogen, nitrates and biochemical oxygen demand (BOD). Acid precipitation and oxidation produced sludge rich in organic matter and nutrients (Ca, Mg, P, Cl, Na and K). Despite the high removal efficiencies, a post-treatment following the precipitation and oxidation processes can be required.
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http://dx.doi.org/10.1016/j.jenvman.2019.109558 | DOI Listing |
Langmuir
January 2025
College of Chemistry and Chemical Engineering, Qingdao University, Qingdao 266071, China.
The recovery of valuable materials from spent lithium-ion batteries (LIBs) has experienced increasing demand in recent years. Current recycling technologies are typically energy-intensive and are often plagued by high operation costs, low processing efficiency, and environmental pollution concerns. In this study, an efficient and environmentally friendly dielectrophoresis (DEP)-based approach is proposed to separate the main components of "black mass" mixtures from LIBs, specifically lithium iron phosphate (LFP) and graphite, based on their polarizability differences.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
Research Center for Energy and Environmental Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki, 305-0044, Japan.
Unveiling the key influencing factors towards electrode/electrolyte interface control is a long-standing challenge for a better understanding of microscopic electrode kinetics, which is indispensable to building up guiding principles for designer electrocatalysts with desirable functionality. Herein, we exemplify the oxygen evolution reaction (OER) via water molecule oxidation with the iridium dioxide electrocatalyst and uncovered the significant mismatching effect of pH between local electrode surface and bulk electrolyte: the intrinsic OER activity under acidic or near-neutral condition was deciphered to be identical by adjusting this pH mismatching. This result indicates that the local pH effect at the electrified solid-liquid interface plays the main role in the "fake" OER performance.
View Article and Find Full Text PDFACS Nano
January 2025
State Key Laboratory of Fine Chemicals, College of Materials Science and Engineering, Shenzhen University, Shenzhen 518055, China.
Biofilm-induced chronic bacterial infections represent a significant challenge in modern medicine due to their resistance to conventional antibiotic treatments. Although photodynamic therapy (PDT) has emerged as a promising antibiotic-free antibacterial strategy, the hypoxic condition within biofilms and the lack of an effective local drug delivery system have limited the clinical effectiveness of photosensitizer (PS) agents. Herein, we propose a type of charge regulation-enhanced type I PS-loaded hydrogel dressing for treating biofilm infection.
View Article and Find Full Text PDFFront Pharmacol
December 2024
Department of Convergence Medical Science, College of Korean Medicine, Kyung Hee University, Seoul, Republic of Korea.
Background: Huntington disease (HD), a neurodegenerative autosomal dominant disorder, is characterized by involuntary choreatic movements with cognitive and behavioral disturbances. Up to now, no therapeutic strategies are available to completely ameliorate the progression of HD. has various pharmacologic effects such as antioxidant and anti-inflammatory activities.
View Article and Find Full Text PDFFront Neurosci
December 2024
Institute of Reconstructive Neurobiology, Medical Faculty and University Hospital of Bonn, University of Bonn, Bonn, Germany.
Brain aging is a chronic process linked to inflammation, microglial activation, and oxidative damage, which can ultimately lead to neuronal loss. Sialic acid-binding immunoglobulin-like lectin-11 (SIGLEC-11) is a human lineage-specific microglial cell surface receptor that recognizes -2-8-linked oligo-/polysialylated glycomolecules with inhibitory effects on the microglial inflammatory pathways. Recently, the gene locus was prioritized as a top tier microglial gene with potential causality to Alzheimer's disease, although its role in inflammation and neurodegeneration remains poorly understood.
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