•An artificial olfactory sensor using 7 flexible MOFs was designed to detect VOCs.•The sensor can sense less-reactive VOCs that conventional dyes are insensitive.•The flexible MOFs show excellent ...reversibility and storage stability.•The sensor demonstrates the potential to identify late blight in the tomato.
An artificial olfactory sensor using seven flexible metal–organic frameworks (MOFs) was designed to detect volatile organic compounds (VOCs) with high selectivity. Owing to its unique colorimetric mechanism, the flexible-MOF-based colorimetric sensor array enables the detection of less-reactive VOCs to which conventional dyes are insensitive. In addition, the flexible MOFs show excellent reversibility toward various VOCs, reusability for repeated cycles toward a single VOC, and storage stability under different humidity and time conditions. Furthermore, the flexible MOF sensor array demonstrates the potential to identify late blight in the tomato crop via the differentiation of the composition of VOCs released by Phytophthora infestans (P. infestans)-infected leaves and those of a healthy control.
Nitrogen oxides (NOx) and volatile organic compounds (VOCs) may cause ozone formation and photochemical smog pollution, which may damage to human health and ecological environment seriously. An ...aerobic Denitrifying BioTrickling Filter (DBTF) for collaborative removal of nitrogen oxides (NOx) and toluene in flue gas was investigated. NOx and toluene removal efficiency were up to 90% and 95%, respectively. Mycobacterium, Comamonas and Pseudomonas were predominant bacteria; Mycobacterium, Pseudomonas, Comamonas, Microbacterium, Reyranella, Stenotrophomonas and Alicycliphilus were the core toluene oxidizing-denitrifying genera, denitrification genes (narGHI, nirK, nasB, napAB, nosZ and norC) and toluene oxidation genes (tom, E1.14.13.7, xyl, cat, todE, tes, mhp, pch, pob, pca, lig, gal) responsible for bacterial oxidation of toluene and NOx reduction, as shown by16S rDNA and metagenomic sequencing. Bacterial oxidation of toluene was coupled to NOx reduction in which toluene served as the electron donor while NOx served as the electron acceptor and thereby redox between toluene and NOx was formed, toluene was degraded through the classical aerobic aromatic compound degradation pathway. DBTF was capable of both toluene oxidation and NOx reduction by denitrification. These results show that the DBTF is achievable and open new possibilities for applying the DBTF to simultaneous removal of NOx and VOCs.
Catalysis in VOC Abatement Ojala, Satu; Pitkäaho, Satu; Laitinen, Tiina ...
Topics in catalysis,
11/2011, Letnik:
54, Številka:
16-18
Journal Article
Recenzirano
Volatile organic compounds (VOCs) are harmful to environment and human health. Catalytic oxidation has been used in VOC abatement for over 60 years, and it has proven to be an effective technology. A ...large variety of VOCs set high demands for the treatment, and therefore catalytic oxidation needs still to be developed further. This paper reviews current aspects and future research needs related to VOCs and catalytic VOC treatment concentrating on solvent-based, chlorinated and sulphur-containing VOCs.
The application of metal–organic frameworks (MOFs) as SERS‐active platforms in multiplex volatile organic compounds (VOCs) detection is still unexplored. Herein, we demonstrate that MIL‐100 (Fe) ...serves as an ideal SERS substrate for the detection of VOCs. The limit of detection (LOD) of MIL‐100(Fe) for toluene sensing can reach 2.5 ppm, and can be even further decreased to 0.48 ppb level when “hot spots” in between Au nanoparticles are employed onto MIL‐100 (Fe) substrate, resulting in an enhancement factor of 1010. Additionally, we show that MIL‐100(Fe) substrate has a unique “sensor array” property allowing multiplex VOCs detection, with great modifiability and expandability by doping with foreign metal elements. Finally, the MIL‐100(Fe) platform is utilized to simultaneously detect the different gaseous indicators of lung cancer with a ppm detection limit, demonstrating its high potential for early diagnosis of lung cancer in vivo.
MIL‐100(Fe) is demonstrated to serve as an ideal “SERS‐active” and “sensory array” platform for multiplex sensing of volatile organic compounds (VOCs) as well as the gaseous biomarkers of diseases with low Raman cross‐sections.
•Fe-Mn oxide was prepared via a new method of redox–precipitation and aging.•Fe was doped in MnO2 lattice and resulted in structural distortion.•The morphology of MnO2 material was transformed from ...nanowires to nanoparticles.•The mechanism of morphological evolution of the material was proposed.•The Fe-Mn oxides showed high activity for o-xylene catalytic oxidation.
Fe-MnO2 nanocomposite was prepared via a redox–precipitation method combined with a subsequent aging treatment at low-temperature. Various characterizations showed that Fe was incorporated into MnO2 lattice that changed the relative intensity of MnO2 crystal planes. Thus, the structural defect was formed and the anisotropic growth of the MnO2 crystallite phase was suppressed. As a result, the morphology of MnO2 was transformed from nanowires to nanoparticles. In addition, the catalytic property of Fe-MnO2 was significantly enhanced than that of pristine MnO2 for the complete oxidation of o-xylene. This work provides a simple and effective strategy for regulating MnO2 texture and activity.
Microplastics (MPs) are recognized as a major environmental problem due to their ubiquitous presence in ecosystems and bioaccumulation in food chains. Not only humans are continuously exposed to ...these pollutants through ingestion and inhalation, but recent findings suggest they may trigger vascular inflammation and potentially worsen the clinical conditions of cardiovascular patients. Here we combine headspace analysis by needle trap microextraction-gas chromatography-mass spectrometry (HS-NTME-GC-MS) and biological assays to evaluate the effects of polystyrene, high- and low-density polyethylene MPs on phenotype, metabolic activity, and pro-inflammatory status of Vascular Smooth Muscle Cells (VSMCs) the most prominent cells in vascular walls. Virgin and artificially aged MPs (4 weeks at 40 °C and 750 W/m2 simulated solar irradiation) were comparatively tested at 1 mg/mL to simulate a realistic exposure scenario. Our results clearly show the activation of oxidative stress and inflammatory processes when VSMCs were cultured with aged polymers, with significant overexpression of IL-6 and TNF-α. In addition, volatile organic compounds (VOCs), including pentane, acrolein, propanal, and hexanal as the main components, were released by VSMCs into the headspace. Type-specific VOC response profiles were induced on vascular cells from different MPs.
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•Using aged PS, HDPE, and LDPE MPs to better simulate real environmental samples.•Aged MPs cause oxidative stress in Vascular Smooth Muscle Cells (VSMCs).•Increased levels of IL-6 and TNF-alpha when MPs are cultured with VSMCs.•Type-specific VOC response profiles were induced on vascular cells from MPs.
Surface enhanced Raman scattering (SERS) is a trace detection technique that extends even to single molecule detection. Its potential application to the noninvasive recognition of lung malignancies ...by detecting volatile organic compounds (VOCs) that serve as biomarkers would be a breakthrough in early cancer diagnostics. This application, however, is currently limited by two main factors: (1) most VOC biomarkers exhibit only weak Raman scattering; and (2) the high mobility of gaseous molecules results in a low adsorptivity on solid substrates. To enhance the adsorption of gaseous molecules, a ZIF‐8 layer is coated onto a self‐assembly of gold superparticles (GSPs) in order to slow the flow rate of gaseous biomarkers and depress the exponential decay of the electromagnetic field around the GSP surfaces. Gaseous aldehydes that are released as a result of tumor‐specific tissue composition and metabolism, thereby acting as indicators of lung cancer, are guided onto SERS‐active GSPs substrates through a ZIF‐8 channel. Through a Schiff base reaction with 4‐aminothiophenol pregrafted onto gold GSPs, gaseous aldehydes are captured with a 10 ppb limit of detection, demonstrating tremendous prospects for in vitro diagnoses of early stage lung cancer.
A high‐sensitivity surface enhanced Raman scattering (SERS) substrate is used for volatile organic compounds (VOCs) detection in exhaled breath, wherein ordered gold superparticles act as SERS hotspots and a metal‐organic‐framework layer is employed to slow the flow rate and strengthen the adsorption of gaseous analytes. Gaseous aldehyde VOCs are captured with a parts per billion limit of detection in this analyte‐detection system.
Acetone, as a kind of typical volatile organic compounds (VOCs), is mainly discharged into the atmosphere through exhaust emissions, fuel combustion, pharmaceuticals, and printing, etc. It not only ...causes water pollution but also inhibits the people’s central nervous system, posing a great threat to the ecological environment and human health. Due to its economy and compatibility, the catalytic oxidation method is considered to be one of the effective methods for removing acetone. The development of low-cost and high-efficiency catalysts can bring higher economic benefits. This review covers the research progress of acetone oxidation by noble metal and non-noble metal catalyst systems, and discusses the effects of metal composition, support, preparation method, and morphology on the catalyst activity. Comparison shows that both manganese-based and cobalt-based catalysts are the good substitutes for precious metal platinum-based and palladium-based catalysts, in which the concentration of oxygen vacancies, the number of active oxygen species, and the interaction between substrates are the key factors. In addition, the possible mechanism of catalytic oxidation of acetone is given, and the development of catalytic oxidation of acetone is prospected.
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•Types of catalysts for acetone removal are summarized.•Research development and mechanistic understanding of catalysts for acetone removal are overviewed.•Mechanism of catalytic oxidation of acetone.
