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Effect of the Addition of Extractives on The Reduction Of Vocs Emissions from Lacquers in the liquid state

Brózdowski Jakub, Gajewski Erik, Szczepaniak Oskar M., Stachowiak-Wencek Agata

Drewno : prace naukowe, doniesienia, komunikaty

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2023

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Vol. 66, nr 211

Art. no. 1644-3985.437.04

EN

The aim of this study was to determine the effect of the addition of extractive substances on the VOC emission of lacquer products in the liquid state. Three water-soluble acrylic resin products were investigated using the stationary phase microextraction technique in combination with gas chromatography coupled with mass spectrometry (SPME-GC/MS). The extraction of volatile compounds was analysed at three temperatures: 22 ℃, 35 ℃ and 45 ℃. 20 μg of an extract obtained from the leaves, branches and bark of black cherry (Prunus serotina Erhr.) were added to commercial products. Flavonoids accounted for almost 75% of the total phenols in the used extract. The spectrum of volatile compounds emitted by the liquid coating products selected for the studies was examined before and after adding the extract to them. It was found that the addition of black cherry extract caused a significant reduction in the emissions of volatile compounds emitted by the researched products. The compounds, whose amounts did not decrease under the influence of the addition of the extract, were esters of propenoic acid. The applied extract was a source of emissions from an additional compound: benzaldehyde. The total VOC emissions of the investigated liquid coating products was reduced by 8-55% and depended on the extraction temperature. The paper also proposes the mechanism of chemical reactions between phenolics and VOC, which may cause the reduction in VOC emissions from lacquer products. The IBM RXN tool was utilised to find possible reactions.

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In Vitro propagation affects the composition of narrow-leaved lavender essential oils

Andrys D., Kulpa D.

Acta Chromatographica

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2018

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Vol. 30, no. 4

225--230

EN

The aim of this study was to identify and determine by means of gas chromatography–flame ionization detector (GC–FID) and gas chromatography–mass spectrometry (GC–MS) method the volatile compounds of essential oils obtained from three varieties of narrow-leaved lavender grown in the field and in in vitro cultures. The essential oils were isolated by hydrodistillation in Deryng apparatus. It was found that the analyzed essential oils varied in terms of chemical composition depending on the variety and conditions of growth. Sixty-four to 87 different compounds were identified in the oils. Essential oils of all 3 varieties obtained in in vitro cultures contained large amounts of borneol (13–32%). This compound was also dominant in plants obtained from in vivo conditions in varieties Ellagance Purple (11%) and Blue River (13%), and in the Munstead variety, the dominant compound was linalool (13%). High concentration of epi-α-cadinol (10–20%) was found in essential oils obtained from in vitro cultured plants. Globulol was found in high concentration (10%) in the Munstead variety grown in in vitro conditions. However, significant quantitative and qualitative differences were found with respect to composition of essential oils obtained from plants grown in the field and in vitro conditions. There was a lack of (E)-β-ocimene, 3-octyn-2-one, 1-octen-3-yl acetate, sabina ketone, pinocarvone, trans-carveol, nerol, epi-longipinanol, or humulene epoxide II. In comparison to oils obtained from field-grown plants, the oils isolated from plants grown in in vitro conditions contained the less volatile compounds identified in the final stage of GC–FID and GC–MS analysis, i.e., thymol, carvacrol, γ-gurjunene, trans-calamene, α-calacorene, khusinol, and 8-cedren-13-ol.

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TG/DTG/DTA, FTIR and GC/MS Studies of Oil Sand for Artistic and Precision Foundry with the Emission of Gases Assessment

Bobrowski A., Żymankowska-Kumon S., Drożyński D., Grabowska B., Kaczmarska K.

Archives of Foundry Engineering

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2017

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Vol. 17, iss. 4

25--30

EN

The paper presents the results of thermoanalytical studies by TG/DTG/DTA, FTIR and GC/MS for the oil sand used in art and precision foundry. On the basis of course of DTG and DTA curves the characteristic temperature points for thermal effects accompanying the thermal decomposition reactions were determined. This results were linked with structural changes occurred in sample. It has been shown that the highest weight loss of the sample at temperatures of about 320°C is associated with destruction of C-H bonds (FTIR). In addition, a large volume of gases and high amounts of compounds from the BTEX group are generated when liquid metal interacts with oil sand. The results show, that compared to other molding sands used in foundry, this material is characterized by the highest gaseous emissions and the highest harmfulness, because benzene emissions per kilogram of oil sand are more than 7 times higher than molding sand with furan and phenolic binders and green sand with bentonite and lustrous carbon carrier.

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Procesy pirolizy i ich wpływ na jakość odlewów oraz na warunki pracy

Holtzer M., Kmita A., Roczniak A.

Prace Instytutu Odlewnictwa

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2016

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Vol. 56, no. 3

175--192

PL

W artykule omówiono procesy termiczne, jakim jest poddawana masa formierska w kontakcie z ciekłym stopem odlewniczym. W zależności od charakteru atmosfery w formie może to być proces spalania lub pirolizy (przy braku tlenu). Procesy te, szczególnie gdy w skład masy wchodzą związki zawierające węgiel (np. masy z żywicami lub z bentonitem i nośnikiem węgla błyszczącego (NWB)), generując odpowiednią atmosferę wewnątrz formy, mają duży wpływ na występowanie takich wad w odlewach, jak: żyłki, przypalenia czy penetracja ciekłego metalu. Aby uniknąć tych wad, należy wytworzyć we wnęce formy atmosferę redukującą. W artykule dokonano obszernego przeglądu prac, w tym również prac własnych autorów, w zakresie procesów pirolizy zachodzących w masach z dodatkiem substancji zawierających węgiel. Przedstawiono schematy mechanizmów rozpadu termicznego żywic oraz NWB podawane przez różnych autorów. Procesy pirolizy generują wiele szkodliwych związków z grupy tzw. Niebezpiecznych Zanieczyszczeń Powietrza (HAPs – Hazardous Air Pollutants), w tym z grupy BTEX (benzen, toluen, etylobenzen i ksyleny) oraz z grupy WWA (wielopierścieniowe węglowodory aromatyczne), co zagraża zdrowiu pracowników odlewni.

EN

The article discusses the thermal processes undergone by the sand mould in contact with the liquid casting alloy. Depending on the character of the atmosphere in the mould, this can be the process of combustion or pyrolysis (when there is no oxygen). These processes, especially when the sand mould contains compounds with carbon, (e.g. sand moulds with resins or bentonite and lustrous carbon formers (LCF)), generating the proper atmosphere inside the mould, have a significant effect on the presence of such casting defects as: veinings, burn-ons and liquid metal penetration. In order to avoid these defects, a reducing atmosphere should be formed inside the mould cavity. The article provides a comprehensive review of the studies, including the authors’ own works, in the scope of the pyrolysis process taking place in sand moulds with the addition of a carbon-containing substance. Diagrams of the mechanisms of the thermal decomposition of resins and lustrous carbon formers (LCF) given by various authors are presented. The pyrolysis processes generate many hazardous compounds from the group of the so-called Hazardous Air Pollutants (HAPs), including those from the BTEX group (benzene, toluene, ethylbenzene and xylenes) as well as from the PAH group (polycyclic aromatic hydrocarbons), which create risks for the health of the foundry workers.

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Assessment of the Harmfulness of Moulding Sands with Alkyd Resin Subjected to the High Temperature Influence

Holtzer M., Dańko R., Żymankowska-Kumon S., Kubecki M., Bobrowski A.

Archives of Metallurgy and Materials

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2016

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Vol. 61, iss. 4

2171--2176

EN

Out of moulding sands used in the foundry industry, sands with organic binders deserve a special attention. These binders are based on synthetic resins, which ensure obtaining the proper technological properties and sound castings, however, they negatively influence the environment. These resins in their initial state these resins are not very dangerous for people and for the environment, thus under an influence of high temperatures they generate very harmful products, being the result of their thermal decomposition. Depending on the kind of the applied resin, under an influence of a temperature such compounds as: furfuryl alcohol, formaldehyde, phenol, BTEX group (benzene, toluene, ethylbenzene, xylene), and also polycyclic aromatic hydrocarbons (PAHs) can be formed and released. The aim of the study was the development of the method, selection of analytical methods and the determination of optimal conditions of formation compounds from the BTEX and PAHs group. Investigations were carried out in the specially designed set up for the thermal decomposition of organic substances in a temperature range: 500 – 1 300°C at the laboratory scale. The object for testing was alkyd resin applied as a binding material for moulding sands. The qualitative and quantitative analyses of compounds were performed by means of the gas chromatography coupled with the mass spectrometry (GC/MS).