Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 3.685
Filtrar
Mais filtros











Intervalo de ano de publicação
1.
BMC Plant Biol ; 24(1): 364, 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38702592

RESUMO

BACKGROUND: This study aimed to investigate the alterations in biochemical and physiological responses of oat plants exposed to antimony (Sb) contamination in soil. Specifically, we evaluated the effectiveness of an arbuscular mycorrhizal fungus (AMF) and olive mill waste (OMW) in mitigating the effects of Sb contamination. The soil was treated with a commercial strain of AMF (Rhizophagus irregularis) and OMW (4% w/w) under two different levels of Sb (0 and 1500 mg kg-1 soil). RESULTS: The combined treatment (OMW + AMF) enhanced the photosynthetic rate (+ 40%) and chlorophyll a (+ 91%) and chlorophyll b (+ 50%) content under Sb condition, which in turn induced more biomass production (+ 67-78%) compared to the contaminated control plants. More photosynthesis in OMW + AMF-treated plants gives a route for phenylalanine amino acid synthesis (+ 69%), which is used as a precursor for the biosynthesis of secondary metabolites, including flavonoids (+ 110%), polyphenols (+ 26%), and anthocyanins (+ 63%) compared to control plants. More activation of phenylalanine ammonia-lyase (+ 38%) and chalcone synthase (+ 26%) enzymes in OMW + AMF-treated plants under Sb stress indicated the activation of phenylpropanoid pathways in antioxidant metabolites biosynthesis. There was also improved shifting of antioxidant enzyme activities in the ASC/GSH and catalytic pathways in plants in response to OMW + AMF and Sb contamination, remarkably reducing oxidative damage markers. CONCLUSIONS: While individual applications of OMW and AMF also demonstrated some degree of plant tolerance induction, the combined presence of AMF with OMW supplementation significantly enhanced plant biomass production and adaptability to oxidative stress induced by soil Sb contamination.


Assuntos
Antimônio , Micorrizas , Olea , Poluentes do Solo , Micorrizas/fisiologia , Olea/microbiologia , Poluentes do Solo/metabolismo , Antimônio/metabolismo , Adaptação Fisiológica , Resíduos Industriais , Fotossíntese/efeitos dos fármacos , Biodegradação Ambiental , Biomassa
2.
Food Res Int ; 187: 114422, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38763672

RESUMO

Tons of orange by-products (OBPs) are generated during industrial orange processing. Currently, OBPs management is challenging due to their high amounts, physico-chemical characteristics (high water content, low pH, presence of essential oils) and seasonal nature of the production. Whereas agro-industrial OBPs can be highly valuable due to their abundant sources of bioactive compounds, which can add value to novel bakery products (e.g. bread, biscuits, cakes). This review covers the most recent research issues linked to the use of OBPs in bakery products, with a focus on available stabilization methods and on the main challenges to designing improved products. The application of OBPs improved the nutritional quality of bakery products, offering interesting sustainability benefits but also critical challenges. The valorization of OBPs may open new routes for the development of new natural ingredients for the food industry and lower food processing waste.


Assuntos
Citrus sinensis , Resíduos Industriais , Citrus sinensis/química , Resíduos Industriais/análise , Manipulação de Alimentos/métodos , Indústria Alimentícia , Pão/análise , Valor Nutritivo , Reciclagem , Indústria de Processamento de Alimentos
3.
Sci Rep ; 14(1): 10723, 2024 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-38730012

RESUMO

Our study investigates the effects of iron oxide (Fe3O4) nanoparticles combined microwave pretreatment on the anaerobic digestibility and soluble chemical oxygen demand (SCOD) of meat industry sludge. One of our main objectives was to see whether the different microwave-based pretreatment procedures can enhance biogas production by improving the biological availability of organic compounds. Results demonstrated that combining microwave irradiation with magnetic iron oxide nanoparticles considerably increased SCOD (enhancement ratio was above 1.5), the rate of specific biogas production, and the total cumulative specific biogas volume (more than a threefold increment), while having no negative effect on the biomethane content. Furthermore, the assessment of the sludge samples' dielectric properties (dielectric constant and loss factor measured at the frequency of 500 MHz) showed a strong correlation with SCOD changes (r = 0.9942, R2 = 0.99), offering a novel method to evaluate pretreatment efficiency.


Assuntos
Nanopartículas Magnéticas de Óxido de Ferro , Micro-Ondas , Esgotos , Esgotos/química , Nanopartículas Magnéticas de Óxido de Ferro/química , Anaerobiose , Carne/análise , Análise da Demanda Biológica de Oxigênio , Biocombustíveis/análise , Indústria Alimentícia , Resíduos Industriais
4.
Waste Manag ; 182: 225-236, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38677140

RESUMO

This article explores the impact of thermally treated asbestos-cement waste (ACWT) on metakaolin-based geopolymers, using liquid sodium silicate (LSS) and liquid potassium silicate (LKS) as alkali activators. Through statistical mixture design, various formulations were tested for rheological parameters, mineralogical composition, efflorescence mass, electrical conductivity, compressive strength, and CO2 emissions. Formulations with sodium silicate exhibited higher yield stress compared to those with potassium silicate, while flash setting occurred in LKS-activated mixtures with high ACWT content. Alkali activator content significantly affected mechanical strength and leachate electrical conductivity. CO2 emissions were higher for LKS-activated formulations but lower for those with more ACWT. Finally, by incorporating ACWT, it was possible to optimize the formulations, resulting in high compressive strength, reduced free ions, and reduced negative environmental impact.


Assuntos
Amianto , Dióxido de Carbono , Materiais de Construção , Silicatos , Dióxido de Carbono/análise , Silicatos/química , Materiais de Construção/análise , Amianto/análise , Força Compressiva , Resíduos Industriais/análise , Condutividade Elétrica , Temperatura Alta
5.
Waste Manag ; 182: 11-20, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38626501

RESUMO

Recycling aluminium in a rotary furnace with salt-fluxes allows recovering valuable alloys from hard-to-recycle waste/side-streams such as packaging, dross and incinerator bottom ash. However, this recycling route generates large amounts of salt-slag/salt-cake hazardous wastes which can pose critical environmental risks if landfilled. To tackle this issue, the metallurgical industry has developed processes to valorise the salt-slag residues into recyclable salts and aluminium concentrates, while producing by-products such as ammonium sulphate and non-metallic compounds (NMCs), with applications in the construction or chemical industries. This study aims to assess through LCA the environmental impacts of recycling aluminium in rotary furnaces for both salt-slag management routes: valorisation or landfill. It was found that this recycling process brings forth considerable net environmental profits, which increase for all the considered impact categories if the salt-slag is valorised. The main benefits arise from the production of secondary cast aluminium alloys, which is not unexpected due to the high energy intensity of aluminium primary production. However, the LCA results also identify other hotspots which play a significant role, and which should be considered for the optimisation of the process based on its environmental performance, such as the production of by-products, the consumption of energy/fuels and the avoidance of landfilling waste. Additionally, the assessment shows that the indicators for mineral resource scarcity, human carcinogenic toxicity and terrestrial ecotoxicity are particularly benefited by the salt-slag valorisation. Finally, a sensitivity analysis illustrates the criticality of the metal yield assumptions when calculating the global warming potential of aluminium recycling routes.


Assuntos
Alumínio , Incineração , Reciclagem , Incineração/métodos , Reciclagem/métodos , Alumínio/química , Alumínio/análise , Meio Ambiente , Resíduos Industriais/análise , Metalurgia
6.
Chemosphere ; 357: 142062, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38636915

RESUMO

Coffee processing wastes, such as solid (pulp and husk) and wastewater, co-digested with industrial brewery wastewater, serve as excellent substrates for generating methane in the anaerobic digestion process. This study compared methane production using different compositions of cattle manure (CM) and granular sludge from an Upflow Anaerobic Sludge Blanket (UASB) reactor used in poultry wastewater treatment (GS). Four anaerobic batch reactors (500 mL) were assembled, A (50% CM and 50% GS), B (60% CM and 40% GS), C (70% CM and 30% of GS) and D (60% CM and 40% GS). Equal concentrations of substrates were added to all reactors: pulp and husk pretreated by hydrothermolysis (1 g L-1), coffee (10 g COD L-1) and brewery (1.5 g COD L-1) wastewaters. Assays A, B and C were supplemented with 2 g L-1 of yeast extract, except for assay D. The reactors were operated at 37 °C and pH 7.0. In assay B, the highest CH4 production of 759.15 ± 19.20 mL CH4 g-1 TS was observed, possibly favored by the synergistic interactions between cellulolytic bacteria Christensenellaceae_R-7_group and Methanosaeta archaea, as inferred by genes encoding enzymes related to acetoclastic methanogenesis (acetyl-CoA synthetase). Consequently, the electricity production potential of assay B (45614.08 kWh-1 year-1) could meet the energy demand of a farm producing coffee and beer, contributing to a positive energy balance concerning methane generation.


Assuntos
Reatores Biológicos , Café , Esterco , Metano , Esgotos , Eliminação de Resíduos Líquidos , Águas Residuárias , Animais , Metano/metabolismo , Bovinos , Anaerobiose , Águas Residuárias/química , Café/metabolismo , Eliminação de Resíduos Líquidos/métodos , Resíduos Industriais , Biocombustíveis
7.
Chemosphere ; 358: 142140, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38688348

RESUMO

Carbon-encapsulated iron oxide nanoparticles (CE-nFe) have been obtained from an industrial waste (oil mill wastewater-OMW, as a carbonaceous source), and using iron sulfate as metallic precursor. In an initial step, the hydrochar obtained has been thermally activated under an inert atmosphere at three different temperatures (600 °C, 800 °C and 1000 °C). The thermal treatment promotes the development of core-shell nanoparticles, with an inner core of α-Fe/Fe3O4, surrounded by a well-defined graphite shell. Temperatures above 800 °C are needed to promote the graphitization of the carbonaceous species, a process promoted by iron nanoparticles through the dissolution, diffusion and growth of the carbon nanostructures on the outer shell. Breakthrough column tests show that CE-nFe exhibit an exceptional performance for H2S removal with a breakthrough capacity larger than 0.5-0.6 g H2S/gcatalyst after 3 days experiment. Experimental results anticipate the crucial role of humidity and oxygen in the adsorption/catalytic performance. Compared to some commercial samples, these results constitute a three-fold increase in the catalytic performance under similar experimental conditions.


Assuntos
Carbono , Sulfeto de Hidrogênio , Resíduos Industriais , Carbono/química , Resíduos Industriais/análise , Sulfeto de Hidrogênio/química , Adsorção , Catálise , Ferro/química , Águas Residuárias/química , Nanopartículas/química , Compostos Férricos/química
8.
J Hazard Mater ; 471: 134295, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38631253

RESUMO

There has been increasing attention given to nickel-cobalt tailings (NCT), which pose a risk of heavy metal pollution in the field. In this study, on site tests and sampling analysis were conducted to assess the physical and chemical characteristics, heavy metal toxicity, and microbial diversity of the original NCT, solidified NCT, and the surrounding soil. The research results show that the potential heavy metal pollution species in NCT are mainly Ni, Co, Mn, and Cu. Simultaneous solidification and passivation of heavy metals in NCT were achieved, resulting in a reduction in biological toxicity and a fivefold increase in seed germination rate. The compressive strength of the original tailings was increased by 20 times after solidification. The microbial diversity test showed that the abundance of microbial community in the original NCT was low and the population was monotonous. This study demonstrates, for the first time, that the use of NCT for solidification in ponds can effectively solidification of heavy metals, reduce biological toxicity, and promote microorganism diversity in mining areas (tended to the microbial ecosystem in the surrounding soil). Indeed, this study provides a new perspective for the environmental remediation of metal tailings.


Assuntos
Cobalto , Níquel , Microbiologia do Solo , Poluentes do Solo , Níquel/toxicidade , Níquel/química , Cobalto/química , Cobalto/toxicidade , Poluentes do Solo/metabolismo , Metais Pesados/toxicidade , Metais Pesados/química , Disponibilidade Biológica , Mineração , Germinação/efeitos dos fármacos , Recuperação e Remediação Ambiental/métodos , Bactérias/metabolismo , Bactérias/efeitos dos fármacos , Força Compressiva , Resíduos Industriais
9.
Chemosphere ; 358: 142132, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38670505

RESUMO

The escalation of industrial activities has escalated the production of pharmaceutical and dyeing effluents, raising significant environmental issues. In this investigation, a hybrid approach of Fenton-like reactions and adsorption was used for deep treatment of these effluents, focusing on effects of variables like hydrogen peroxide concentration, catalyst type, pH, reaction duration, temperature, and adsorbent quantity on treatment effectiveness, and the efficacy of acid-modified attapulgite (AMATP) and ferric iron (Fe(III))-loaded AMATP (Fe(III)-AMATP) was examined. Optimal operational conditions were determined, and the possibility of reusing the catalysts was explored. Employing Fe3O4 as a heterogeneous catalyst and AMATP for adsorption, CODCr was reduced by 78.38-79.14%, total nitrogen by 71.53-77.43%, and phosphorus by 97.74-98.10% in pharmaceutical effluents. Similarly, for dyeing effluents, Fe(III)-AMATP achieved 79.87-80.94% CODCr, 68.59-70.93% total nitrogen, and 79.31-83.33% phosphorus reduction. Regeneration experiments revealed that Fe3O4 maintained 59.48% efficiency over three cycles, and Fe(III)-AMATP maintained 62.47% efficiency over four cycles. This work offers an economical, hybrid approach for effective pharmaceutical and dyeing effluent treatment, with broad application potential.


Assuntos
Compostos Férricos , Peróxido de Hidrogênio , Resíduos Industriais , Compostos de Magnésio , Compostos de Silício , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Compostos Férricos/química , Adsorção , Compostos de Silício/química , Compostos de Magnésio/química , Peróxido de Hidrogênio/química , Catálise , Ferro/química , Fósforo/química , Nitrogênio/química , Corantes/química , Concentração de Íons de Hidrogênio , Purificação da Água/métodos
10.
J Hazard Mater ; 470: 134234, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38608584

RESUMO

Agricultural waste management poses a significant challenge in circular economy strategies. Olive mill wastes (OMW) contain valuable biomolecules, especially phenolic compounds, with significant agricultural potential. Our study evaluate the effects of phenolic extract (PE) derived from olive mill solid wastes (OMSW) on pomegranate agro-physiological and biochemical responses, as well as soil-related attributes. Pomegranate plants were treated with PE at doses of 100 ppm and 200 ppm via foliar spray (L100 and L200) and soil application (S100 and S200). Results showed increased biomass with PE treatments, especially with soil application (S100 and S200). Proline and soluble sugar accumulation in leaves suggested plant adaptation to PE with low-level stress. Additionally, PE application reduced malondialdehyde (MDA) and hydrogen peroxide (H2O2) contents. Higher doses of PE (S200) significantly improved net photosynthesis (Pn), transpiration rate (E), water use efficiency (WUEi), and photosynthetic efficiency (fv/fm and PIabs). Furthermore, PE treatments enhanced levels of chlorophylls, carotenoids, polyphenols, flavonoids, and antioxidant activity. Soil application of PE also increased soil enzyme activities and microbial population. Our findings suggest the beneficial impact of PE application on pomegranate agro-physiological responses, laying the groundwork for further research across various plant species and soil types to introduce nutrient-enriched PE as an eco-friendly biostimulant.


Assuntos
Olea , Fenóis , Punica granatum , Punica granatum/química , Fenóis/análise , Olea/química , Solo/química , Resíduos Industriais , Resíduos Sólidos , Rizosfera , Fotossíntese/efeitos dos fármacos , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Microbiologia do Solo , Peróxido de Hidrogênio/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/química , Agricultura
11.
Int J Mol Sci ; 25(7)2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38612793

RESUMO

The evolution of regulatory perspectives regarding the health and nutritional properties of industrial hemp-based products (Cannabis sativa L.) has pushed research to focus on the development of new methods for both the extraction and formulation of the bioactive compounds present in hemp extracts. While the psychoactive and medicinal properties of hemp-derived cannabinoid extracts are well known, much less has been investigated on the functional and antimicrobial properties of hemp extracts. Within the hemp value chain, various agricultural wastes and by-products are generated. These materials can be valorised through eco-innovations, ultimately promoting sustainable economic development. In this study, we explored the use of waste from industrial light cannabis production for the extraction of bioactive compounds without the addition of chemicals. The five extracts obtained were tested for their antimicrobial activity on both planktonic and sessile cells of pathogenic strains of the Candida albicans, Candida parapsilosis, and Candida tropicalis species and for their antioxidant activity on HT-29 colon cancer cells under oxidative stress. Our results demonstrated that these extracts display interesting properties both as antioxidants and in hindering the development of fungal biofilm, paving the way for further investigations into the sustainable valorisation of hemp waste for different biomedical applications.


Assuntos
Anti-Infecciosos , Cannabis , Neoplasias do Colo , Candida , Antioxidantes/farmacologia , Aderências Teciduais , Biofilmes , Resíduos Industriais
12.
Waste Manag ; 180: 36-46, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38503032

RESUMO

As a by-product of the steelmaking industry, the large-volume production and accumulation of steel converter slag cause environmental issues such as land occupation and dust pollution. Since metal salts of unsaturated carboxylic acid can be used to reinforce rubber, this study explores the innovative application of in-situ modified steel slag, mainly comprising metal oxides, with methacrylic acid (MAA) as a rubber filler partially replacing carbon black. By etching the surface of steel slag particles with MAA, their surface roughness was increased, and the chemical bonding of metal methacrylate salt was introduced to enhance their interaction with the molecular chain of natural rubber (NR). The results showed that using the steel slag filler effectively shortened the vulcanization molding cycle of NR composites. The MAA in-situ modification effectively improved the interaction between steel slag and NR molecular chains. Meanwhile, the physical and mechanical properties, fatigue properties, and dynamic mechanical properties of the experimental group with MAA in-situ modified steel slag (MAA-in-situ-m-SS) were significantly enhanced compared with those of NR composites partially filled with unmodified slag. With the dosage of 7.5 phr or 10 phr, the above properties matched or even exceeded those of NR composites purely filled with carbon black. More importantly, partially replacing carbon black with modified steel slag reduced fossil fuel consumption and greenhouse gas emission from carbon black production. This study pioneered an effective path for the resourceful utilization of steel slag and the green development of the steelmaking and rubber industries.


Assuntos
Borracha , Resíduos Sólidos , Aço/química , Fuligem , Resíduos Industriais/análise , Metais , Metacrilatos
13.
Environ Sci Pollut Res Int ; 31(13): 19795-19814, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38367113

RESUMO

Mill scale (MS) is considered to be a significant metallurgical waste, but there is no economical method yet to utilize its metal content. In this study, which covers various processes in several stages, the solution of iron in MS, which is the Iron and Steel Industry (I&SI) waste, as FeCl3 (MS-FeCl3) in the thermoreactor in the presence of HCl, was investigated. In the next step, the conditions for using this solution as a coagulant in the treatment of I&SI wastewater were investigated using the jar test. The results of the treated water sample were compared by chemical oxygen demand (COD), total suspended solids (TSS), color, and turbidity analyses using commercial aluminum sulfate (Al2(SO4)3) and FeCl3 (C-FeCl3). Additionally, heavy metal analyses were conducted, and the treatment performance of three coagulants was presented. Accordingly, while 2.0 mg/L anionic polyelectrolyte was consumed at a dosage of 4.05 mg/L Al2(SO4)3 at pH 7.0, 0.25 mg/L anionic polyelectrolyte was consumed at a dosage of 1.29 mg/L at pH 5.0 in the C-FeCl3 and MS-FeCl3 studies. Also, Fe, Cr, Mn, Ni, Zn, Cd, Hg, and Pb removal efficiencies were over 93.56% for all three coagulant usage cases. The results showed that the wastewater treatment performance of MS-FeCl3 by the recycling of MS, which is an I&SI waste, was at the same level as C-FeCl3. Thus, thanks to recycling, waste scale can be used as an alternative to commercial products for green production.


Assuntos
Cloretos , Compostos Férricos , Poluentes Químicos da Água , Purificação da Água , Eliminação de Resíduos Líquidos/métodos , Ferro/análise , Resíduos Industriais/análise , Polieletrólitos , Floculação , Poluentes Químicos da Água/análise
14.
Int J Biol Macromol ; 261(Pt 2): 129922, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38309403

RESUMO

Ecological retanning agent is an effective way to solve the pollution source of leather manufacturing industry. In this study, the gelatin from chrome-containing leather shavings in the leather industry was used to realize sustainable leather post-tanning. The gelatin hydrolysate (GH) coordinated with Zr4+ or Al3+ to prepare eco-friendly retanning agents GH-Zr and GH-Al. The successful coordination between GH and metal ions was characterized by FTIR and XPS. The retanning agents were characterized by FTIR curve-fitting and circular dichroism spectroscopy. The results showed that the conformation of the secondary structure of the polypeptide became ordered and stable after coordinating with the metal ions. The particle size and weight average molecular weight of the retanning agents were ~1700 nm and ~2100, respectively, measured by nanoparticle size analyzer and gel permeation chromatography (GPC). The retanning agents were applied to retanning of chrome tanned leather and glutaraldehyde tanned leather. The abundant free amino from retanning agents can consume the free formaldehyde. Meanwhile, retanning agents can effectively improve the multiple binding sites, resulting in favorable thickening rate (>110 %) and excellent dye and fatliquor absorption rate with ~99.91 % and ~93.18 %. Thus, this strategy can provide a viable choice for solid leather waste and sustainable development of the leather industry.


Assuntos
Gelatina , Curtume , Alumínio/análise , Zircônio , Íons/análise , Resíduos Industriais/análise
15.
Environ Sci Pollut Res Int ; 31(13): 20117-20132, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38374501

RESUMO

Produced water (PW) is the largest by-product that comes out of the oil wells during oil and gas (O&G) field exploration. PW contains high-salt concentration along with other organic and inorganic components; therefore, PW must be treated before disposal. Electrocoagulation (EC) is an effective treatment method to remove pollutants from PW which has been the focus of many experimental studies; however, a mathematical model specifically for PW treatment by EC has not been developed yet. In this work, a comprehensive mathematical model has been developed to elucidate the role of EC operating parameters on the PW treatment performance and determine the mechanism for COD (Chemical Oxygen Demand) removal. The present model considers and identifies the dominant Al-hydroxy complex species and their contribution to the COD removal from synthetic PW samples by estimating their rate constants and comparing their magnitudes and investigates multi-scale modelling of the EC reactor. The influence of working parameters such as current density, initial pH, interelectrode distance, mixing speed and solution volume of PW on Al coagulant production and COD removal was investigated and modelled. The study estimates the rate constants of the reactions taking place for COD removal by EC process and by comparing their magnitudes identifies the dominant reactions and coagulant species involved in the process. The mathematical model prediction of COD removal fits well with the experimental data at 10 mA cm-2, 15 mA cm-2 and 20 mA cm-2 current density with R2 value of 0.96, 0.97 and 0.92, respectively and for dissolved Al concentration R2 value of 0.96, 0.99, and 0.97, respectively. The simulated results reproduced a good fit at initial pH of 6.1, 7.3 and 8.6 with R2 value of 0.92, 0.96 and 0.98, respectively for COD removal. The mathematical model and the experimental results showed the role of dominant Al-hydroxy complex species such as Al OH 2 + , Al OH 2 + , Al OH 3 , Al 2 OH 2 + 4 and Al OH 4 - in controlling the COD removal process. Under different operating conditions considered in the study, the model also predicted the COD removal performance of the EC reactors at different reactor volumes with R2 value of 0.96 for higher solution volume and larger reactor. The model presented and rate constants determined in the study will provide a theoretical basis for designing, scaling up and operating the EC reactor for oil-field PW treatment.


Assuntos
Águas Residuárias , Poluentes Químicos da Água , Eliminação de Resíduos Líquidos/métodos , Alumínio , Água , Campos de Petróleo e Gás , Concentração de Íons de Hidrogênio , Eletrodos , Eletrocoagulação/métodos , Modelos Teóricos , Poluentes Químicos da Água/análise , Resíduos Industriais
16.
Environ Res ; 250: 118508, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38395333

RESUMO

Industrial processes and municipal wastes largely contribute to the fluctuations in iron (Fe) content in soils. Fe, when present in unfavorable amount, causes harmful effects on human, flora, and fauna. The present study is an attempt to evaluate the composition of Fe in surface soils from paper mill and municipal landfill sites and assess their potential ecological and human health risks. Geochemical fractionation was conducted to explore the chemical bonding of Fe across different fractions, i.e., water-soluble (F1) to residual (F6). Different contamination factors and pollution indices were evaluated to comprehend Fe contamination extent across the study area. Results indicated the preference for less mobile forms in the paper mill and landfill, with 26.66% and 43.46% of Fe associated with the Fe-Mn oxide bound fraction (F4), and 57.22% and 24.78% in the residual fraction (F6). Maximum mobility factor (MF) of 30.65% was observed in the paper mill, and 80.37% in the landfill. The enrichment factor (EF) varied within the range of 20 < EF < 40, signifying a high level of enrichment in the soil. The individual contamination factor (ICF) ranged from 0 to >6, highlighting low to high contamination. Adults were found to be more vulnerable towards Fe associated health risks compared to children. The Hazard Quotient (HQ) index showed the highest risk potential pathways as dermal contact > ingestion > inhalation. The study offers insights into potential Fe contamination risks in comparable environments, underscoring the crucial role of thorough soil assessments in shaping land use and waste management policies.


Assuntos
Ferro , Papel , Poluentes do Solo , Instalações de Eliminação de Resíduos , Ferro/análise , Poluentes do Solo/análise , Humanos , Medição de Risco , Monitoramento Ambiental , Resíduos Industriais/análise , Fracionamento Químico , Solo/química , Adulto , Criança
17.
Environ Geochem Health ; 46(2): 59, 2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38280129

RESUMO

Heavy metal(loid) (HM) contamination in agricultural soils, particularly in areas severely impacted by smelting industries, has attracted worldwide attention. In this study, agricultural soils were collected in a flourishing multimetal smelting area near the Yellow River in central China. By an integrated approach encompassing the positive matrix factorization model, ordinary kriging interpolation and hierarchical clustering analysis (PMF-OK-HC), a total of four major sources and their mass contributions were identified, namely, soil parent material (56.6%), industrial waste and Mo smelting (24.0%), metal smelting and traffic emissions (12.8%), and coal combustion (6.7%). On this basis, the health risk of HMs was evaluated by Monte Carlo simulations and showed that a higher risk, with a higher proportion of exceeding-thresholds risk, was observed for children than for adults in terms of both noncarcinogenic and carcinogenic risks. Exposure pathways of oral ingestion in children could result in a higher attributed risk than other pathways. Furthermore, source-oriented risk assessment (SORA) revealed that the sources of coal combustion, industrial waste and Mo smelting had the highest contributions to noncarcinogenic and carcinogenic risks. Overall, for effective environmental management in agricultural soil, the framework of SORA was verified as an effective tool in the identification of the priority control of HMs and their sources.


Assuntos
Metais Pesados , Poluentes do Solo , Criança , Adulto , Humanos , Solo , Resíduos Industriais , Rios , Poluentes do Solo/análise , Monitoramento Ambiental , Metais Pesados/análise , China , Medição de Risco , Carvão Mineral
18.
Environ Sci Pollut Res Int ; 31(10): 15078-15090, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38286931

RESUMO

Green and low-carbon materialization for dredged sediment (DS) is limited due to its low pozzolanic activity. In this study, a novel DS-based non-sintered lightweight aggregate (LWA) is developed by steel slag (SS) and fly ash (FA) activation. Process optimization is performed by the response surfaces, and the basic properties and characterization of the optimal product are investigated. Results indicated that the optimized design ceramic aggregate (ODCA) was prepared as follows: raw pellets comprising of 59.2% DS, 5% SS, 35.8% FA, 5% MK, 5% H2O2, and 2‰ foam stabilizer were activated by alkali activator (1.5 weight ratio of 14 M NaOH to water glass) and then cured at 80 °C and 95% humidity for 24 h. The basic and environmental performances of ODCA were in accordance with standards, whose bulk density was as low as 665.8 kg/m3, the high cylinder compressive strength was 6.143 MPa, and leaching concentrations of heavy metals were controllable. The regulation mechanism of LWA performances could be summarized as follows. SS and FA additives played the role for the mechanical strength enhancement and passivation of heavy metals, which promoted the formation of sillimanite, chabazite, and C-S-H / C-S-A-H gels in ODCA. The bulk density of ODCA was greatly reduced by H2O2 addition, where ODCA had an open-pore structure with a median pore size of 4969.75 nm. Note that C-S-H/C-S-A-H were the key hydration products to give ODCA light density and high mechanical strength, simultaneously.


Assuntos
Cinza de Carvão , Misturas Complexas , Metais Pesados , Cinza de Carvão/química , Resíduos Industriais/análise , Aço , Peróxido de Hidrogênio , Metais Pesados/química
19.
Arch Microbiol ; 206(2): 60, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38197951

RESUMO

Biosurfactants are naturally occurring, surface-active chemicals generated by microorganisms and have attracted interest recently because of their numerous industrial uses. Compared to their chemical equivalents, they exhibit qualities that include lower toxic levels, increased biodegradable properties, and unique physiochemical properties. Due to these traits, biosurfactants have become attractive substitutes for synthetic surfactants in the pharmaceutical industry. In-depth research has been done in the last few decades, demonstrating their vast use in various industries. This review article includes a thorough description of the various types of biosurfactants and their production processes. The production process discussed here is from oil-contaminated waste, agro-industrial waste, dairy, and sugar industry waste, and also how biosurfactants can be produced from animal fat. Various purification methods such as ultrafiltration, liquid-liquid extraction, acid precipitation, foam fraction, and adsorption are required to acquire a purified product, which is necessary in the pharmaceutical industry, are also discussed here. Alternative ways for large-scale production of biosurfactants using different statistical experimental designs such as CCD, ANN, and RSM are described here. Several uses of biosurfactants, including drug delivery systems, antibacterial and antifungal agents, wound healing, and cancer therapy, are discussed. Additionally, in this review, the future challenges and aspects of biosurfactant utilization in the pharmaceutical industry and how to overcome them are also discussed.


Assuntos
Antibacterianos , Indústria Farmacêutica , Animais , Adsorção , Antifúngicos , Resíduos Industriais
20.
Environ Res ; 248: 118282, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38295974

RESUMO

The escalating consumer demand for crabs results in a growing amount of waste, including shells, claws, and other non-edible parts. The resulting crab shell waste (CSW) is disposed of via incineration or landfills which causes environmental pollution. CSW represents a potential biological resource that can be transformed into valuable resources via pyrolysis technique. In this study, microwave pyrolysis of CSW using self-purging, vacuum, and steam activation techniques was examined to determine the biochar production yield and its performance in treating palm oil mill effluent (POME). The biochar produced through microwave pyrolysis exhibits yields ranging from 50 to 61 wt%, showing a hard texture, low volatile matter content (≤34.1 wt%), and high fixed carbon content (≥58.3 wt%). The KOH-activated biochar demonstrated a surface area of up to 177 m2/g that is predominantly composed of mesopores, providing a good amount of adsorption sites for use as adsorbent. The biochar activated with steam removed 8.3 mg/g of BOD and 42 mg/g of COD from POME. The results demonstrate that microwave pyrolysis of CSW is a promising technology to produce high-quality biochar as an adsorbent for POME treatment.


Assuntos
Braquiúros , Carvão Vegetal , Animais , Óleo de Palmeira , Micro-Ondas , Pirólise , Vapor , Resíduos Industriais/análise
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA