Hydrothermal Transformations of Organic Matter of Carbon-Rich Domanik Rock in Carbon Dioxide Environment at Different Temperatures

2020 ◽  
Vol 60 (3) ◽  
pp. 278-290
Author(s):  
G. P. Kayukova ◽  
A. N. Mikhailov ◽  
I. P. Kosachev ◽  
V. P. Morozov ◽  
A. V. Vakhin
Keyword(s):  
Carbon Dioxide ◽  
Organic Matter ◽  
Different Temperatures ◽  
Domanik Rock

scholarly journals The Effect of the Temperature and Moisture to the Permeation Properties of PEO-Based Membranes for Carbon-Dioxide Separation

Polymers ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 2053
Author(s):  
Dragutin Nedeljkovic
Keyword(s):  
Carbon Dioxide ◽  
Partial Pressure ◽  
Carbon Dioxide Emission ◽  
Combustion Products ◽  
Mixed Matrix Membranes ◽  
Mixed Matrix Membrane ◽  
Mixed Matrix ◽  
Gas Treatment ◽  
Carbon Dioxide Separation ◽  
Different Temperatures

An increased demand for energy in recent decades has caused an increase in the emissions of combustion products, among which carbon-dioxide is the most harmful. As carbon-dioxide induces negative environmental effects, like global warming and the greenhouse effect, a decrease of the carbon-dioxide emission has emerged as one of the most urgent tasks in engineering. In this work, the possibility for the application of the polymer-based, dense, mixed matrix membranes for flue gas treatment was tested. The task was to test a potential decrease in the permeability and selectivity of a mixed-matrix membrane in the presence of moisture and at elevated temperature. Membranes are based on two different poly(ethylene oxide)-based polymers filled with two different zeolite powders (ITR and IWS). An additive of detergent type was added to improve the contact properties between the zeolite and polymer matrix. The measurements were performed at three different temperatures (30, 60, and 90 °C) under wet conditions, with partial pressure of the water equal to the vapor pressure of the water at the given temperature. The permeability of carbon-dioxide, hydrogen, nitrogen, and oxygen was measured, and the selectivity of the carbon-dioxide versus other gases was determined. Obtained results have shown that an increase of temperature and partial pressure of the vapor slightly increase both the selectivity and permeability of the synthesized membranes. It was also shown that the addition of the zeolite powder increases the permeability of carbon-dioxide while maintaining the selectivity, compared to hydrogen, oxygen, and nitrogen.

scholarly journals Determination of Oleanolic and Ursolic Acids inHedyotis diffusaUsing Hyphenated Ultrasound-Assisted Supercritical Carbon Dioxide Extraction and Chromatography

2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
Ming-Chi Wei ◽  
Yu-Chiao Yang ◽  
Show-Jen Hong
Keyword(s):  
Carbon Dioxide ◽  
Supercritical Carbon Dioxide ◽  
High Performance ◽  
Extraction Yield ◽  
Extraction Time ◽  
Different Temperatures ◽  
Ultrasound Assisted ◽  
High Concentrations ◽  
Static Extraction ◽  
Supercritical Carbon

Oleanolic acid (OA) and ursolic acid (UA) were extracted fromHedyotis diffusausing a hyphenated procedure of ultrasound-assisted and supercritical carbon dioxide (HSC–CO2) extraction at different temperatures, pressures, cosolvent percentages, and SC–CO2flow rates. The results indicated that these parameters significantly affected the extraction yield. The maximal yields of OA (0.917 mg/g of dry plant) and UA (3.540 mg/g of dry plant) were obtained at a dynamic extraction time of 110 min, a static extraction time of 15 min, 28.2 MPa, and 56°C with a 12.5% (v/v) cosolvent (ethanol/water = 82/18, v/v) and SC–CO2flowing at 2.3 mL/min (STP). The extracted yields were then analyzed by high performance liquid chromatography (HPLC) to quantify the OA and UA. The present findings revealed thatH. diffusais a potential source of OA and UA. In addition, using the hyphenated procedure for extraction is a promising and alternative process for recovering OA and UA fromH. diffusaat high concentrations.

Carbocentric limnology: looking back, looking forward

2008 ◽  
Vol 65 (3) ◽  
pp. 543-548 ◽  
Author(s):  
Yves T Prairie
Keyword(s):  
Carbon Dioxide ◽  
Organic Matter ◽  
Microbial Community ◽  
Organic Carbon ◽  
Dissolved Organic Carbon ◽  
Carbon Budget ◽  
Metabolic Balance ◽  
Lake Ecosystems ◽  
Looking Back ◽  
Landscape Level

In this perspective article, I argue that dissolved organic carbon occupies a central role in the functioning of lake ecosystems, comparable in importance to that played by nutrients. Because lakes receive so much dissolved organic carbon from the terrestrial landscape, its accumulation in water bodies usually represents the largest pool of lacustrine organic matter within the water column. The transformation of even a small fraction of this external carbon by the microbial community can alter significantly the metabolic balance of lake ecosystems, simultaneously releasing carbon dioxide to the atmosphere and burying organic carbon in lake sediments. At the landscape level, even if they occupy a small fraction of the landscape, lakes play a surprisingly important role in the regional carbon budget, particularly when considered at the appropriate temporal scale.

scholarly journals Carbon dioxide and methane fluxes at the air–sea interface of Red Sea mangroves

2018 ◽  
Vol 15 (17) ◽  
pp. 5365-5375 ◽  
Author(s):  
Mallory A. Sea ◽  
Neus Garcias-Bonet ◽  
Vincent Saderne ◽  
Carlos M. Duarte
Keyword(s):  
Carbon Dioxide ◽  
Organic Matter ◽  
Red Sea ◽  
Ghg Emissions ◽  
Eastern Coast ◽  
Relative Role ◽  
Emission Rates ◽  
Mangrove Forests ◽  
Ch4 Production

Abstract. Mangrove forests are highly productive tropical and subtropical coastal systems that provide a variety of ecosystem services, including the sequestration of carbon. While mangroves are reported to be the most intense carbon sinks among all forests, they can also support large emissions of greenhouse gases (GHGs), such as carbon dioxide (CO2) and methane (CH4), to the atmosphere. However, data derived from arid mangrove systems like the Red Sea are lacking. Here, we report net emission rates of CO2 and CH4 from mangroves along the eastern coast of the Red Sea and assess the relative role of these two gases in supporting total GHG emissions to the atmosphere. Diel CO2 and CH4 emission rates ranged from −3452 to 7500 µmol CO2 m−2 d−1 and from 0.9 to 13.3 µmol CH4 m−2 d−1 respectively. The rates reported here fall within previously reported ranges for both CO2 and CH4, but maximum CO2 and CH4 flux rates in the Red Sea are 10- to 100-fold below those previously reported for mangroves elsewhere. Based on the isotopic composition of the CO2 and CH4 produced, we identified potential origins of the organic matter that support GHG emissions. In all but one mangrove stand, GHG emissions appear to be supported by organic matter from mixed sources, potentially reducing CO2 fluxes and instead enhancing CH4 production, a finding that highlights the importance of determining the origin of organic matter in GHG emissions. Methane was the main source of CO2 equivalents despite the comparatively low emission rates in most of the sampled mangroves and therefore deserves careful monitoring in this region. By further resolving GHG fluxes in arid mangroves, we will better ascertain the role of these forests in global carbon budgets.

scholarly journals Quality and shelf life of packaged fresh sliced mushrooms stored at two different temperatures

2008 ◽  
Vol 15 (4) ◽  
pp. 414 ◽  
Author(s):  
E. GONZÁLEZ-FANDOS ◽  
A. SIMON JIMENES ◽  
V. TOBAR PARDO
Keyword(s):  
Carbon Dioxide ◽  
Shelf Life ◽  
Agaricus Bisporus ◽  
Microbiological Quality ◽  
Air Atmosphere ◽  
Pvc Film ◽  
Different Temperatures ◽  
Aerobic And Anaerobic ◽  
Quality And Shelf Life

The sensory and microbiological quality of sliced mushrooms (Agaricus bisporus L.) packaged in films of perforated and non-perforated PVC and stored at 3 and 9ºC, was studied. The carbon dioxide and oxygen content inside the packages, colour, weight loss, sensory attributes, mesophiles, Pseudomonas, Enterobacteriaceae, aerobic and anaerobic spore formers were determined. The atmosphere generated with the perforated PVC film was similar to that of air atmosphere at 3 or 9ºC. T.he non-perforated PVC film generated inside the packages CO2 : O2 concentrations of 3.4% : 8.1% at 3ºC and CO2 : O2 concentrations of 4.5% : 0.15% at 9ºC. Browning of mushrooms was lower at 3 than at 9ºC. The quality of sliced mushrooms packaged in perforated PVC and stored at 3ºC was adequate after 9 days. However, at 9ºC, the slice deformation and brown blotches incidence were severe after 9 days. The atmosphere generated with non-perforated PVC inhibited aerobic microorganism growth compared to mushrooms packaged in perforated PVC. At 3ºC, the shelf life of mushrooms packaged in non perforated PVC was around 13 days. However, the extremely low O2 atmospheres generated at 9ºC was accompanied by off-odours and growth of anaerobic spore formers, although the appearance of sliced mushrooms was acceptable.;

scholarly journals Effects of ozonation and temperature on biodegradation of natural organic matter in biological granular activated carbon filters

2010 ◽  
Vol 3 (1) ◽  
pp. 107-132 ◽  
Author(s):  
L. T. J. van der Aa ◽  
L. C. Rietveld ◽  
J. C. van Dijk
Keyword(s):  
Carbon Dioxide ◽  
Organic Matter ◽  
Activated Carbon ◽  
Organic Carbon ◽  
Natural Organic Matter ◽  
Granular Activated Carbon ◽  
Carbon Dioxide Production ◽  
Oxygen Removal ◽  
Theoretical Maximum ◽  
Increasing Temperature

Abstract. Four pilot (biological) granular activated carbon ((B)GAC) filters were operated to quantify the effects of ozonation and water temperature on the biodegradation of natural organic matter (NOM) in (B)GAC filters. Removal of dissolved organic carbon (DOC), assimilable organic carbon (AOC) and oxygen and the production of carbon dioxide were taken as indicators for NOM biodegradation. Ozonation stimulated DOC and AOC removal in the BGAC filters, but had no significant effect on oxygen removal and carbon dioxide production. The temperature had no significant effect on DOC and AOC removal, while oxygen removal and carbon dioxide production increased with increasing temperature. Multivariate linear regression was used to quantify these relations. In summer the ratio between oxygen consumption and DOC removal exceeded the theoretical maximum of 2.5 g O2·g C−1 and the ratio between carbon dioxide production and DOC removal exceeded the theoretical maximum of 3.7 g CO2·g C−1. Bioregeneration of large NOM molecules could explain this excesses and the non-correlation between DOC and AOC removal and oxygen removal and carbon dioxide production. However bioregeneration of large NOM molecules was considered not likely to happen, due to sequestration.

Stabilization of organic carbon isolated from cryoconite holes in polar and mountain systems by 13С NMR spectroscopy

2021 ◽  
Author(s):  
Vjacheslav Polyakov ◽  
Evgeny Abakumov
Keyword(s):  
Carbon Dioxide ◽  
Organic Matter ◽  
Nmr Spectroscopy ◽  
Humic Acids ◽  
Carbon Dioxide Emissions ◽  
Heterogeneous Systems ◽  
Basic Research ◽  
13C Nmr Spectroscopy ◽  
The Arctic ◽  
Additional Contribution

<p>Black carbon is one of the short-lived climatically significant factors. This term refers to climate-forming substances that are located for a short amount of time in the atmosphere - from several days to several years. To identify the role of cryoconite in the conditions of a possible climatic crisis, the stabilization of organic matter isolated from cryoconite holes was assessed. Humic acids are part of the organic matter accumulating in soils and cryoconites and are heterogeneous systems of high-molecular condensed compounds formed as a result of the decomposition of organic remains of plants and animals in terrestrial and aquatic ecosystems. Climatic parameters, precursors of humification, and the local position in the landscape determine the diversity of the composition and properties of HAs. Stabilization of organic material is defined as the transformation of organic matter into a state inaccessible to soil microorganisms, and the very property of stabilization is a characteristic stage in the dynamics of carbon. Using 13C NMR spectroscopy, we determined the proportion of aromatic and aliphatic compounds in the composition of HAs in order to assess the stabilization of organic matter in cryoconites from Mount Elbrus (Caucasus Mountains, Russia), the Arctic (Severnaya Zemlya archipelago, Russia) and Antarctica (King George Island, West Antarctica).</p><p>Samples for qualitative analysis of carbon accumulated in cryoconites were carried out during fieldwork in 2020. The studied samples were analyzed at the Department of Applied Ecology, St. Petersburg State University. Humic acids (HAs) were extracted from each sample according to a published IHSS protocol. Solid-state CP/MAS <sup>13</sup>C-NMR spectra of HAs were measured with a Bruker Avance 500 NMR spectrometer.</p><p>Thus, it follows from the obtained results that aliphatic fragments of humic acids predominate in all studied cryoconites. A similar composition of humic acids testifies to a single mechanism of accumulation and development of organic matter in glacier regions. Low biological activity and climatic features prevent condensation of high-molecular compounds in the organic matter of cryoconite holes. This is an essential prerequisite for high rates of carbon dioxide emissions into the atmosphere under the conditions of deglaciation of the studied regions. With the thawing of glaciers and the ingress of cryoconites into warmer conditions, an additional contribution of carbon dioxide to the atmosphere can occur and, therefore, increase the possible climate crisis on our planet.</p><p>This study was supported by Russian Foundation for Basic Research No. 19-05-50107.</p>

Temperature sensitivity of simulated soils with biochars produced at different temperatures

Soil Research ◽  
2019 ◽  
Vol 57 (3) ◽  
pp. 294 ◽  
Author(s):  
Xiaojie Wang ◽  
Guanhong Chen ◽  
Renduo Zhang
Keyword(s):  
Organic Matter ◽  
Dissolved Organic Matter ◽  
Temperature Sensitivity ◽  
Pyrolysis Temperature ◽  
Soil C ◽  
Ambient Temperatures ◽  
C Pools ◽  
C Cycle ◽  
Microbial Enzyme ◽  
Different Temperatures

The temperature sensitivity of multiple carbon (C) pools in the soil plays an important role in the C cycle and potential feedback to climate change. The aim of this study was to investigate the temperature sensitivity of different biochars in soil to better understand the temperature sensitivity of different soil C pools. Biochars were prepared using sugarcane residue at temperatures of 300, 500 and 800°C (representing different C pools) and C skeletons (representing the refractory C pool in biochar) were obtained from each biochar. The sugarcane residue, biochars and C skeletons were used as amendments in a simulated soil with microbes but without organic matter. The temperature sensitivity of the amended soils was characterised by their mineralisation rate changes in response to ambient temperatures. The temperature sensitivity of treatments with relatively refractory biochars was higher than that with labile biochars. The temperature sensitivity of treatments with biochars was lower than for their corresponding C skeletons. The different temperature sensitivity of treatments was attributable to the different internal C structures (i.e. the functional groups of C=C and aromatic structure) of amendments, determining the biodegradability of substrates. Dissolved organic matter and microbial enzyme activity of biochars were lower than those of corresponding C skeletons, and decreased with increasing pyrolysis temperature. The temperature sensitivities of treatments with biochars, C skeletons and sugarcane residue were negatively correlated with the properties of dissolved organic matter and microbial enzyme activities (especially dehydrogenase) in soil.

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