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1

Analiza wybranych konstrukcji wielozłożowego adsorpcyjnego układu chłodniczego

Neska Mirosław, Opara Tadeusz, Majcher Andrzej

Przemysł Chemiczny

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2024

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T. 103, nr 1

73--78

PL

Omówiono budowę i funkcjonowanie prostego, jednozłożowego adsorpcyjnego układu chłodniczego. Dokonano analizy wybranych konstrukcji układów wielozłożowych. Zweryfikowano opracowany prototyp własnego rozwiązania systemu adsorpcyjnego. Zaprezentowano przykładowe wyniki z weryfikacji układu, dla którego osiągnięto temperaturę w parowniku na poziomie ok. 6°C. Innowacyjnym elementem tego układu był kształt prototypowych adsorberów ze stali nierdzewnej, które są wykonane jako dwa różne rozwiązania konstrukcyjne: walcowo-krzyżowy i walcowo-rurowy. Prezentowane systemy adsorpcyjne, ze względu na swoje parametry pracy, mogą być wykorzystywane do zagospodarowania niskotemperaturowego ciepła odpadowego w przemyśle.

EN

The construction and operation of a simple single-bed adsorption refrigeration system were discussed. Selected designs of multi-bed systems were analyzed. A verified prototype of our own soln. of a threebed adsorption refrigeration system was presented. Examples of results from the verification of the system for which the temp. in the evaporator was reached at the level of approx. 6°C were presented. An innovative element of the system was the shape of the prototype stainless steel adsorbers, which were made in 2 different design solns.: cylindrical-cross and cylindrical-tube. Due to their operational parameters, the presented adsorption systems can be used for the management of low-temp. waste heat in industry.

2

Adsorption and desorption characteristics of rare earth ions on halloysite surfaces

Long Qibang, Yan Huashan, Zhou Xiaowen, Qiu Sen, Qiu Tingsheng

Physicochemical Problems of Mineral Processing

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2024

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Vol. 60, iss. 1

art. no. 185763

EN

Rare earths (REs) are primarily adsorbed in ionic form on the surface of clay minerals such as halloysite in ionic rare earth ores. As a result, understanding the adsorption and desorption behaviors of RE ions on the surface of the halloysite may contribute to clarifying the mineralization process of ionic rare earth ores and provide a theoretical framework for the optimization of the extraction process. The adsorption and desorption characteristics of light (Nd3+), medium (Eu3+), and heavy (Lu3+) RE ions on the surface of halloysite-10 Å were comprehensively examined in this study. Because REs are more inclined to form an outer layer and inner layer adsorption when halloysite is protonated and deprotonated with the range of pH, respectively, pH has a significant impact on how halloysite adsorbs and desorbs. The experiment findings indicate that RE concentration, duration, and pH all increased the adsorption capacity of light, medium, and heavy REEs, and exhibited some selectivity for heavy REEs. Nd3+, Eu3+ and Lu3+ ions adsorption processes on the surface of Halloysite-10 Å are consistent with the Langmuir isothermal adsorption model and pseudo-second-order kinetic equations. The desorption efficiency of Lu3+ decreases dramatically with increasing pH due to hydrolysis and more inner layer adsorption than that of Nd3+ and Eu3+.

3

Cleaning and Management of Water Contaminated with Pesticides through the Process of Adsorption in the Natural Clay of Brari

Behrami Esad, Berbatovci Isak, Xhaxhiu Kledi, Isak Nensi, Andoni Adelaida, Reka Arianit, Hamiti Xhuljeta, Musliu Zehra Hajrulai, Uzunov Risto

Ecological Engineering & Environmental Technology

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2024

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Vol. 25, iss. 2

281--291

EN

This study aimed to investigate the potential for widespread application of clay in the purification of water polluted with pesticides and water management through the absorption and desorption of dimethoate and methomyl in the natural clay of Brari (Tirana). While the maximum adsorption of methomyl on Brari clay was reached in 12 hours, the maximum adsorption of dimethoate on Brari clay was reached in 48 hours. To compare the adsorption of methomyl and dimethoate on Brari clay, their water degradation time was also taken into account. Dimethoate dissolves quickly; a contact period of 1–2 hours is sufficient to desorb 81.2% of the material. Dimethoate dissolves in water at 25 °C and has a half-life t1/2 = 30 days. Methomyl is desorbed even faster; in just two hours, 96.2% of the material is desorbed. At 25 °C, dimethoate has a half-life of t1/2 = 14 days and a high solubility of 58 g/L in water. Because methomyl and dimethoate bind poorly to clay, they can contaminate surface and groundwater.

4

Removal of silver from chloride solutions using new polymer materials

Pilśniak-Rabiega Magdalena, Wolska Joanna

Physicochemical Problems of Mineral Processing

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2023

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Vol. 59, iss. 6

art. no. 174357

EN

This work presents the synthesis of polymer resins with heterocyclic functional groups, that is, N-(3-aminopropyl)-2-pipecoline, N-(3-aminopropyl)-2-pyrrolidinone, and trans-1,4-diaminocyclohexane for the recovery of Ag(I) from chloride solutions. The modification yield was 69.2, 74.6 and 88.3%, respectively. The best Ag(I) sorption was achieved from synthetic and real chloride solutions in the case of trans-1,4-diaminocyclohexane resin (sorption was 26.8 and 21.5 mg/g, respectively). The sorption kinetic data were well fitted to the pseudo-first-order kinetic model. The maximum sorption capacity of Ag(I) is 105.4, 117.8 and 130.7 mg Ag(I)/g for N-(3-aminopropyl)-2-pipecoline resin, N-(3-aminopropyl)-2-pyrrolidinone resin and trans-1,4-diaminocyclohexane resin, respectively. The trans-1,4-diaminocyclohexane modified resin was very selective towards Ag(I) compared to Cu(II), Pb(II), and Zn(II) from the real chloride leaching solution. The N-(3-aminopropyl)-2-pipecoline and N-(3-aminopropyl)-2-pyrrolidinone resins showed high preferences for Ag(I) over Pb(II) in real solution. These results indicated that the polymers can be applied in the recovery of Ag(I).

5

Effects of cations on rare earth adsorption and desorption in binding sites of montmorillonite

He Zhengyan, Nie Wenrui, Yang Huifang, Tang Yuchen, Sha Aoyang, Qu Jun, Xu Zhigao, Chi Ruan

Physicochemical Problems of Mineral Processing

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2023

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Vol. 59, iss. 3

art. no. 168280

EN

The exchangeability of rare earth (RE) in weathered crust elution-deposited rare earth ores largely depends on its interaction with clay minerals, which may be significantly influenced by various cations. Therefore, the effects of K+, Ca2+ and Al3+ on RE3+ adsorption and desorption in binding sites of montmorillonite (MMT) were investigated. Through the pre-saturation, the interlayer ions of MMT had been replaced by K+, Ca2+ or Al3+. RE3+ can adsorb on the interlayer sites of Ca-MMT and K-MMT, but nearly not Al-MMT. The basal spacing of Ca-MMT is larger than K-MMT, which provides a smaller hinder effect of interlayer collapse for the interlayer diffusion of RE3+. The adsorption capacity followed the order: Ca-MMT＞K-MMT＞Al-MMT and La3+＞Y3+＞Eu3+. It can predict that the grade of the exchangeable RE in ores abundant in Ca2+ is the most, followed by the ore rich in K+ and Al3+ the least. Clay minerals tend to adsorb light RE and hard to adsorb middle and heavy RE. The reversibility of RE adsorbed in interlayers, especially in collapsed interlayers, is far worse than that on externals. The desorption rates of RE were in the order of RE-Al-MMT＞RE-K-MMT＞RE-Ca-MMT and Eu3+＞Y3+＞La3+. For the desorption of interlayer RE3+, NH4+ is better than Mg2+ because the larger change of the basal spacings (Δd) provides more minor activation energy barriers (ΔE) for NH4+ diffusion within interlayers. It can enrich the metallogeny theory of weathered crust elution-deposited rare earth ores and provide a certain theoretical basis for its efficient exploitation.

6

Recovery of Niobium Pentaoxide and Ammonium Sulfate from Titanium-Magnesium Production Waste

Ultarakova Almagul, Lokhova Nina, Karshyga Zaure, Toishybek Azamat, Yessengaziyev Azamat, Kassymzhanov Kaisar, Mukangaliyeva Arailym

Journal of Ecological Engineering

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2023

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Vol. 24, nr 11

227--235

EN

This study was aimed to investigate the development of a technology for the extraction of niobium pentaoxide and ammonium sulfate from titanium-magnesium production waste, specifically, the sublimates of dust chamber into concentrate in the form of niobium pentoxide. Optimal conditions for washing the niobium hydroxide precipitate by repulpation with hot (60–70°C) distilled water, drying at 200°C for 6 hours were determined. The influence of temperature and duration of the process was studied. Optimal conditions for the dynamic desorption of niobium from saturated ionite (Purolite A100) was determined. The results further indicated that the optimum quantity of the solution of desorption with sulfuric acid was equal to 5.5% and ammonium oxalate was equal to 4%, while temperature and the flow rate of the desorbing solution was 22–27°C and 6 rpm, respectively. The study of the precipitation of niobium from sulfuric acid desorbates showed that the interaction of niobium ions with ammonia takes place at a low rate. The degree of precipitation of niobium hydroxide equal to 99.6% was achieved in 7 hours of agitation of the suspension at a temperature of 22–25°C.

7

Effect of Magnetite Oxide Nanoparticles and Tungsten Oxide Nanoparticles on Phosphate Removal from Aqueous Solutions

EL-Baz Amro, Mokhtar Mona, Abdo Ahmed

Journal of Ecological Engineering

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2023

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Vol. 24, nr 3

287--303

EN

Phosphate (P) removal from aqueous solutions were studied by a new mineral adsorbent, tungsten (VI) oxide (WO3) nanoparticles (NPs), which has not been the subject of much research in the field of removing P contaminants from agricultural wastewater. In this paper, P was removed from aqueous solutions by a new mineral adsorbent, WO3 NPs and it was compared with magnetite (iron IV) oxide (Fe3O4) nanoparticles (NPs) under the same ambient operating conditions i.e., The influence of the dosage of adsorbents, initial P concentration, contact time, pH and temperature. The values that achieved the best removal were recorded. It was concluded that the best limits for pH were at 2–3, contact time at 40 minutes, temperature at 45 °C and adsorbent dose at 1.0 g/L. Best results of the variables were applied on samples of real agricultural wastewater, which achieved removal ratio of 77.3% and 75.42% for Fe3O4 and WO3 NPs, respectively. SEM, EDX and FTIR images and analyses were conducted to describe the characteristics of nano-adsorbents used before and after P adsorption in aqueous solutions. The P adsorption kinetics for aqueous solutions were examined by fitting results of the experiment to both the first & second pseudo-kinetically models. The outcome indicated that kinematic data fit better with pseudo-second-order kinetic models. Moreover, the information captured from equilibrium adsorption was analyzed using isothermal methods (by Langmuir & Freundlich Forms). Their results showed that the Freundlich form is considered more suitable than Langmuir form in analyzing the biosorption of P ions. The thermodynamic demeanor of P adsorption by Fe3O4 and WO3 NPs was analyzed and evaluated, and the thermodynamic data analyses confirmed the process of P adsorption was spontaneous. The ΔG° value was negative, while ΔH° and ΔS° values found to be positive, which means that the adsorption of P was a spontaneous, random and endothermic operation. In general, Fe3O4 and WO3 nanoparticles had a high efficiency in removing phosphate from water. In addition, WO3 NPs has been identified as one of the most promising adsorbents due to its rapid and effective adsorption of pollutants.

8

Cleaning of Pesticide-Contaminated Water Using Natural Clays

Behrami Esad, Avdiu Vahid

Journal of Ecological Engineering

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2023

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Vol. 24, nr 6

13--24

EN

The primary purpose of this research was the study of two natural clays Dardha (Korçë), which is located at 40°31'16.59'' N and 20°49'33.69'' E and the clay of Brari (Tirana), 41°21'14.49'' N and 19°50'17.74'' E for the removal of dimethoate, in order to clean the waters polluted with this pesticide. During the Clay-water+dimethoate contact time from 0 to 24 hours, there was spontaneous hydrolysis of dimethoate, which also theoretical data accurately explains this phenomenon. Clay-water+dimethoate contact time longer than 120 hours are not of interest for this study, because after this time there is no adsorption of dimethoate. Our experimental study focused on contact times from 24 to 120 hours. The adsorption process of dimethoate with concentrations of 0.2 mg/mL was studied; 0.3 mg/mL and 0.5 mg/mL in the natural clays of Dardhe and Brari. The desorption process of dimethoate from these clays was also studied. The desorption process was fast, where in the first two hours of contact 80 to 95% dimethoate was desorbed.

9

Badanie efektów cieplnych towarzyszących adsorpcji i desorpcji wybranych gazów na węglach w zrobach ścian polskich kopalń węgla kamiennego

Szumna Anna, Stefański Damian, Prażuch Magdalena

Przemysł Chemiczny

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2021

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T. 100, nr 8

737--742

PL

Przedstawiono wyniki badań efektów cieplnych towarzyszących sorpcji i desorpcji ditlenku i tlenku węgla, metanu, etanu, propanu i wodoru na węglach w zrobach ścian eksploatowanych pokładów: 510 w kopalni Wesoła, 505 w kopalni Jankowice i 405/2 w kopalni Bielszowice. Węgle z tych pokładów charakteryzują się zbliżonym stopniem uwęglenia oraz skłonnością do samozapalenia. Tego typu węgle są najczęściej eksploatowane w Polsce. Badania wykonano w temp. 308 K techniką mikrokalorymetrii przepływowej. Wykazano, że największe ilości ciepła wydzielane są podczas adsorpcji ditlenku węgla, a mniejsze podczas adsorpcji węglowodorów nasyconych (metan, etan, propan). Gazy o najmniejszym cieple adsorpcji to CO i wodór. Taką zależność uzyskano dla wszystkich badanych węgli.

EN

Bituminous coal samples of specified elementary compn., petrographic characteristics and particle size distribution collected from longwall gobs of exploited seams of 3 Polish coal mines were tested by microcalorimetry technique. The heats of adsorption and desorption of CO₂, CO, CH₄, C₂H₆, C₃H₈ and H₂ on the coal samples were detd. CO₂ showed the highest value of the heat of adsorption and CO and H₂ the lowest. Effect of coal fragmentation on gas adsorption heat was also tested. The adsorption heat increased with the increase in the amt. of larger diam. grains in the sample.

10

Destruction of the Structure of Boiling Emulsions

Pavlenko Anatoliy, Melnyk Viktor

Rocznik Ochrona Środowiska

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2020

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Tom 22, cz. 1

70--81

EN

In this paper we consider the processes of dynamic interaction between the boiling particles of the dispersed phase of the emulsion leading to the large droplet breakup. It is indicated the differences in the consideration of forces that determine the crushing of non-boiling and boiling drops. It is determined the possibility of using the model to define the processes of displacement, deformation or fragmentation of the inclusion of the dispersed phase under the influence of a set of neighboring particles. The proposed method allows us to determine the main energy parameters of the homogenization process by boiling the emulsion.

PL

W tym artykule rozważamy procesy dynamicznej interakcji między wrzącymi cząsteczkami zdyspergowanej fazy emulsji, prowadzące do rozpadu dużych kropel. Wskazano na różnice w uwzględnianiu sił, które determinują kruszenie kropli niewrzących i wrzących. Określono możliwość wykorzystania modelu do zdefiniowania procesów przemieszczenia, deformacji lub fragmentacji włączenia fazy rozproszonej pod wpływem zestawu sąsiednich cząstek. Proponowana metoda pozwala określić główne parametry energetyczne procesu homogenizacji podczas ogrzewania i wrzenia emulsji.

11

Usuwanie jonów Cu2+ z roztworów wodnych za pomocą wybranych sorbentów

Bożęcka Agnieszka, Orlof-Naturalna Monika, Korpalski Aleksander

Przemysł Chemiczny

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2020

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T. 99, nr 10

1501--1504

PL

Przedstawiono wyniki badań dotyczących usuwania jonów Cu2+ z roztworów wodnych za pomocą węgla aktywnego Norit SX2, zmielonych łusek ryżu oraz żywicy jonowymiennej C-160. Badane procesy sorpcji opisano za pomocą modelu adsorpcji Langmuira. Najlepszymi parametrami sorpcyjnymi charakteryzował się jonit C-160. Stwierdzono, że łuska ryżowa i węgiel aktywny to skuteczne sorbenty w roztworach rozcieńczonych. Odzysk miedzi w procesie regeneracji węgla aktywnego, jonitu oraz łuski ryżowej był duży. Wydajność desorpcji wyniosła odpowiednio 98,12%, 92,31% i 88,90%.

EN

The Cu2+ ions were adsorbed from their aq. solns. (10–10 000 mg/L) on com. activated C, milled rice husks and an ion-exchange resin in Na form under stirring (200 rpm) for 60 min and then desorbed by using aq. HCl soln. (10% by mass). The adsorption followed the Langmuir isotherm model. The most efficient removal of the Cu2+ ions took place on the ion-exchange resin while the rice husks and activated C were effective sorbents only in diluted solns. The recovery of Cu2+ ions from activated C, ion-exchange resin and rice husk was 98.12%, 92.31% and 88.90%, resp.

12

Termodesorpcja argonu implantowanego do germanu

Turek Marcin, Droździel Andrzej, Pyszniak Krzysztof, Vaganov Yuriy A.

Przegląd Elektrotechniczny

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2020

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R. 96, nr 8

126--130

PL

Badano termodesorpcję Ar zaimplantowanego do germanu (z energią 100 keV i 150 keV, dawka 2×1016 cm-2). Zaobserwowano gwałtowne uwolnienia Ar w temperaturach 790-840 K w postaci wąskich wierzchołków w widmach TDS, co świadczy najprawdopodobniej o uwalnianiu Ar zgromadzonego w postaci bąbli we wnękach w Ge. Analiza przesunięć położenia wierzchołków pozwoliła oszacować wartości energii aktywacji desorpcji – wynosi ona 3.2 eV (100 keV) i 2.2 eV (150 keV) - znacznie więcej niż uzyskane w przypadku He implantowanego do Ge.

EN

Thermal desorption of Ar implanted into germanium (with energies 100 keV and 150 keV, fluence 2×1016 cm-2) was studied. Sudden release of Ar was observed as narrow peaks in temperature range 790-840 K in TDS spectra, which may be assigned to the release of gas trapped as bubbles in cavities in the Ge lattice. The analysis of peak shifts enabled estimation of desorption activation energies - it is 3.2 eV (100 keV) and 2.2 eV (150 keV) - these values are much larger than those measured for He implanted into Ge.

13

Ablation of single-crystalline cesium iodide by extreme ultraviolet capillary-discharge laser

Wild Jan, Pira Peter, Burian Tomas, Vysin Ludek, Juha Libor, Zelinger Zdenek, Danis Stanislav, Nehasil Vaclav, Rafaj Zdenek, Nevrly Vaclav, Dostal Michal, Bitala Petr, Kudrna Pavel, Tichy Milan, Rocca Jorge J.

Nukleonika

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2020

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Vol. 65, No. 4

205--210

EN

Extreme ultraviolet (XUV) capillary-discharge lasers (CDLs) are a suitable source for the efficient, clean ablation of ionic crystals, which are obviously difficult to ablate with conventional, long-wavelength lasers. In the present study, a single crystal of cesium iodide (CsI) was irradiated by multiple, focused 1.5-ns pulses of 46.9-nm radiation delivered from a compact XUV-CDL device operated at either 2-Hz or 3-Hz repetition rates. The ablation rates were determined from the depth of the craters produced by the accumulation of laser pulses. Langmuir probes were used to diagnose the plasma plume produced by the focused XUV-CDL beam. Both the electron density and electron temperature were sufficiently high to confirm that ablation was the key process in the observed CsI removal. Moreover, a CsI thin film on MgO substrate was prepared by XUV pulsed laser deposition; a fraction of the film was detected by X-ray photoelectron spectroscopy.

14

Nowa metoda interpretacji przestrzeni porowej na podstawie łączenia badań porozymetrii rtęciowej i adsorpcji azotu na przykładzie wybranych łupków menilitowych

Dudek Lidia

Nafta-Gaz

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2020

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R. 76, nr 5

291--298

PL

W artykule przedstawiono nowe podejście do interpretacji charakterystyki przestrzeni porowej, polegające na połączeniu pochodnych różnic objętości porowych – wyników porozymetrii rtęciowej i adsorpcji azotu na wspólnej skali, bez stosowania jakichkolwiek sztucznych przesunięć danych. To nowe podejście zastosowano wykorzystując wyniki pomiarów próbek łupków menilitowych pobranych z powierzchni terenu. Jest ono oparte na przyjętym założeniu, że w zakresie dowolnie wybranych średnic porowych istniejąca objętość porowa jest niezależna od użytego typu cieczy niezwilżającej (rtęć, ciekły azot, ciekły argon itp.). Jakiekolwiek różnice pomiarowe wynikające z tych dwóch pomiarów są konsekwencją mechanicznego pękania ścianek porów pod wpływem wysokich ciśnień rtęci lub też ich odkształceń elastycznych i\lub plastycznych oraz innych interakcji pomiędzy materiałem ścianek porów a zastosowaną cieczą niezwilżającą. Znaczące populacje porów w łupkach są zbyt małe, aby mierzyć je tylko za pomocą MICP (ang. Mercury Injection Capillary Pressure), co wyjaśniałoby niedoszacowanie całkowitej połączonej objętości porowej. Dlatego też do jej określenia zastosowano uzupełniającą metodę adsorpcji azotu. Struktura porowa próbek łupków menilitowych wygrzanych w 105°C była mierzona metodą porozymetrii rtęciowej w temperaturze otoczenia oraz metodą adsorpcji azotu w temperaturze wrzenia ciekłego azotu −195,8°C. Rozkłady pochodnych objętości względem średnicy porów otrzymanych z tych dwóch uzupełniających się metod zostały przedstawione w postaci wykresów zależności dV/dD. Na podstawie badań porozymetrycznych i piknometrii helowej obliczono porowatość całkowitą i otwartą, co pozwoliło na scharakteryzowanie własności filtracyjnych próbek skał. Na podstawie badań adsorpcyjnych obliczono powierzchnię właściwą BET, rozkład wielkości porów i zajmowaną przez nie objętość.

EN

In this paper, a new approach has been shown for the interpretation of the pore space characteristics, consisting in combining pore space volumetric fractional derivatives of mercury intrusion and nitrogen adsorption on the same scale without using any artificial data transformation. This new approach was shown using obtained results of measurements of surface Menilite Shales. It is based on the assumption that for any selected pore diameters, the existing pore space volume is independent of the applied non-wetting liquid agent (mercury, liquid nitrogen, liquid argon etc.). Any recorded differences of these two methods are due to cracking of pore walls under high mercury pressure or their elastic and/or plastic deformations and other interactions between pore building material and the non-wetting liquid used. Significant populations of pores in shales are too small to be measured using only MICP (Mercury Injection Capillary Pressure), which would explain the underestimation of the total porous space. Therefore, for its proper estimation, the complementary method of nitrogen adsorption has been used. The porous structure of Menilite Shale samples preheated at 105°C was measured using the mercury intrusion method MICP at ambient temperature and using nitrogen adsorption at its boiling point temperature of −195.8°C. Volumetric fractional derivatives of pore diameters obtained by these 2 different complementary methods were shown in the form of graphs dV/dD. Based on the porosimetric and helium pycnometric tests both bulk and open porosity was calculated, which allowed to characterise the filtration properties of rock samples. Based on the adsorption testing, the specific surface BET was calculated, as well as the pore size distribution and its total porous volume.

15

Study of the impact of exploitation structures on pressure distribution and adsorbed methane content in coal seams using dynamic flow models. A case study

Szott Wiesław, Miłek Krzysztof, Łętkowski Piotr, Gołąbek Andrzej

Mining Science

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2020

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Vol. 27

133--153

EN

One of the most serious difficulties encountered during the estimation of results of various methods of methane drainage from coal seams is the determination of the initial condition of the analysed coal seam prior to commencement of the actual process of methane drainage. It is well known that the exploitation operation in adjacent coal seams, as well as preparatory works in the analysed seam may significantly modify the original state of methane adsorption in that seam, as well as influence the distribution of pore pressure and saturation of its natural fractures with fluids (gas, water). This state is of dynamic nature and depends on a long and complex history of the mining activity in the analysed facility and its surrounding. Detailed specification of the above condition is usually replaced by qualitative and very approximate models, which does not allow for consideration of the process preceding the methane drainage. The subject of the paper is the quantitative evaluation of the initial conditions for a coal seam with the use of dedicated simulation models of the analysed seam along with its broad surroundings. Results of this modelling including modifications of appropriate transport parameters of layers between the seams and their influence on detailed distribution of pore pressures, levels of methane desorption from the coal matrix, directions of reservoir fluids flow (methane, water) and saturation with these fluids in natural fractures of the selected seam, as well as in the pores of overburden and underburden rocks will be thoroughly analysed for determination of spacious and temporal effects of the mining activities in terms of their influence on the selected seam.

16

Effective Removal of Iron (II) from Aqueous Solution by Adsorption using Zn/Cr Layered Double Hydroxides Intercalated with Keggin Ion

Oktriyanti Melantina, Palapa Neza Rahayu, Mohadi Risfidian, Lesbani Aldes

Journal of Ecological Engineering

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2020

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Vol. 21, nr 5

63--71

EN

Zn/Cr and Zn/Cr layered double hydroxides (LDHs) intercalated with Keggin ion [α-SiW12O40]4-were successfully synthesized at room temperature and pH value of 10. The synthesized materials were characterized by means of the XRD, BET, and FT-IR analyses and used as an adsorbent iron(II). The adsorption process was investigated by studying pH, the kinetics, and thermodynamic properties of the adsorption process. The results showed the interlayer Zn/Cr LDHs was 7.53 Å and increase to 10.26 Å on Zn/Cr LDHs intercalated with Keggin ion [α-SiW12O40]4-. The BET analysis showed that the pore volume of both materials increased from 0.063 cm3 g-1 to 0.163 cm3 g-1. The pH point zero charge measurement for the Zn/Cr LDHs material was 10 while LDHs Zn/Cr intercalated with Keggin ion [α-SiW12O40]4- was 8. Zn/Cr LDHs intercalated with Keggin ion [α-SiW12O40]4- has higher adsorption capacity than Zn/Cr LDHs without intercalation. Desorption of iron (III) was successfully conducted using HCl as reagent showing the involvement of ion exchange in the adsorption.

17

Model adsorpcyjnej pompy ciepła – porównanie wyników dla równania równowagi adsorpcji Dubinina-Astachowa i Totha

Zwarycz-Makles Katarzyna

Instal

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2020

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nr 7

6--12

PL

W artykule przedstawiono jednowymiarowy model analityczny adsorpcyjnej pompy ciepła, porównując uzyskane wyniki przy zastosowaniu opisu równowagi adsorpcji równaniem Dubinina-Astachowa i równaniem równowagi Totha. Rozpatrywana jest jednostopniowa adsorpcyjna pompa ciepła silikażel – woda. Przyjęto, że adsorber zbudowany jest z rurek, na których osadzony jest adsorbent (silikażel). Opracowany model może posłużyć do określania charakteru pracy urządzenia oraz zmian temperatur, stężeń i strumieni ciepła w adsorberze/desorberze. Model został rozwiązany przy użyciu arkusza kalkulacyjnego. W obliczeniach prowadzonych z uwzględnieniem równania równowagi Totha zaobserwowano wyższe współczynniki SHP i SCP oraz wzrost ilości ciepła dostarczonego/ odprowadzonego do adsorbera, co wpłynęło na wzrost współczynników COP.

EN

In the presented paper the adsorber analytical modeling results based on Dubinin-Astakhov adsorption equilibrium and Toth adsorption equilibrium of water vapour on silica gel were compared. The adsorption heat pump with silica gel adsorbent and water adsorbate was discussed. A conventional single stage cycle adsorption heat pump is modeled. The design of the adsorber/desorber considered element is the tube with deposited silica gel bed. The analytical model was created to describe the temperature and concentration changes in the adsorber/desorber and consequently to describe the performance of the adsorption heat pump. The mathematical model was solved using common spreadsheet. A considerable increase in the calculated SHP and SCP in the model based on the Toth equilibrium equation as well as slight increase in the heat supplied or released from adsorbent influenced the increase in the COP.

18

A dynamic model for the heat transfer behavior of a cooling system

Liu Wen, Zhang Chi, Hu Xiao-Xiong, Cao Jian-Bo, Liu Li-Jiao, Ye Xin-Y, Lin Li, Qi Xun-Ji

Control and Cybernetics

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2020

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Vol. 49, No. 3

315--332

EN

For purposes of studying the heat transfer behavior of various fluids in a refrigeration system, a dynamic model is established, obtained on the basis of analysis concerning the effects of adsorption velocity, adsorbent bed temperature, condensing temperature, and heat transfer fluids, as well as changes of external conditions. It is demonstrated that adsorption velocity increases sharply in the initial phase of adsorption process and gradually declines after reaching a peak value, whereas condensing temperature increases sharply in the initial phase of desorption process and decreases after reaching a peak value with the desorption quantity decreasing. Furthermore, the increase of heat source temperature and the decrease of cooling water temperature can advance the adsorption process. The present study therefore suggests some ways of improving the performance of such a refrigeration system by increasing heat source temperature, decreasing ambient air temperature, increasing return air temperature and decreasing cooling water temperature.

19

Interaction of selected pesticides with mineral and organic soil components

Barchańska Hanna, Czaplicka Marianna, Kyzioł-Komosińska Joanna

Archives of Environmental Protection

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2020

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Vol. 46, no. 3

80--91

EN

The pesticide persistence, in particular in soils, often significantly exceeding the declarations of their manufacturers is surprising. There are many publications devoted to the explanation of this phenomenon in the fi eld literature, but the diverse research methodologies used may lead to the ambiguous conclusions. On the basis of the collected literature, the attempt was made to systematize the available information on the interactions of commonly used groups of pesticides with individual soil components. The complex mechanisms of interactions between pesticides and soil based on van der Waals forces, ionic and covalent bonding, ligand exchange and charge transfer complexes formation were demonstrated. It was also proved that the nature of interactions is strictly dependent on the structure of the pesticide molecule. The conclusion of the review may contribute to the choice of plant protection products that, in addition to their effectiveness, are as little ballast for the environment as possible.

20

Wpływ zmian temperatury i czasu wygrzewania próbek skał mułowców na rozkład wielkości porów i powierzchnię właściwą BET na podstawie analiz izoterm adsorpcji

Dudek Lidia

Nafta-Gaz

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2019

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R. 75, nr 1

10--16

PL

Celem pracy jest przedstawienie efektów wygrzewania próbek skał ilasto-mułowcowych na ich strukturę porową, a konkretnie powierzchnię właściwą BET. Struktura porowa surowych i częściowo wygrzanych próbek była mierzona metodą adsorpcji azotu w niskiej temperaturze, w tym przypadku w temperaturze wrzenia ciekłego azotu. Otrzymane izotermy adsorpcji i desorpcji tych próbek były podobne i można je było zaklasyfikować jako typ II, według klasyfikacji IUPAC (Sing et al., 1985). Badania adsorpcyjne wykonano na próbkach skał ilastomułowcowych z utworów ordowiku i syluru oraz fliszu karpackiego. Selekcję próbek przeprowadzono na podstawie analizy składu mineralogicznego, opierając się na ilościowej analizie rentgenowskiej (tabela 3). Głównym kryterium wyboru była zawartość węglanu wapnia, ze względu na to, iż przyjmuje się, że węglany nie ulegają żadnym przemianom poniżej 550°C. Okazało się jednak, że przemiany następują już w znacznie niższych temperaturach. Dla każdej próbki wykonano co najmniej 30 pomiarów adsorpcyjnych, w sumie wykonując ich około 120 pomiarów. Otrzymano krzywe kumulacyjne oraz funkcje rozkładu objętości porów wyznaczone za pomocą algorytmu BJH (ang. Barrett-Joyner-Halenda) (Barrett et al., 1951), z gałęzi desorpcji przy użyciu równania statystycznej grubości warstwy Halseya i korekcji Faass (Faass, 1981) oraz wartości powierzchni właściwej BET (Brunauer et al., 1938). Analizując otrzymane wyniki można stwierdzić, że wszystkie próbki przed przystąpieniem do badania – w celu minimalizacji błędów pomiarowych związanych z heterogenicznością – należy przesiać przez sito 0,5 mm. Następnie po wygrzaniu i przedmuchaniu próbki w urządzeniu SmartPrep należy zatkać probówkę korkiem w celu eliminacji ponownego zawilgocenia. Konsekwencją wygrzewania próbki już nawet w temperaturze 65°C jest wzrost wartości Ro o 3%, lecz przy wygrzewaniu w 425°C rośnie ona aż o 500%. Po wykonaniu analizy adsorpcji azotem zauważono, że wszystkie próbki, niezależnie od ich współczynnika wzrostu lub spadku powierzchni właściwej BET z temperaturą, wykazują tendencję do lokalnych minimów w zakresie 130–190°C i 360–425°C oraz lokalnych maksimów 65–105°C i 250–320°C, których to wyjaśnienie powinno być przedmiotem osobnej pracy analizującej szczegółowo zjawiska fizycznochemiczne występujące w podobnym trendzie we wszystkich analizowanych próbkach.

EN

The purpose of this work was to show the effects of heating up of mudstones rock samples, on their pore structure and especially on their specific surface BET. Porous structures of both – raw and partly heated samples – were measured using nitrogen adsorption method at low temperature i.e. boiling temperature of liquid nitrogen. Adsorption and desorption isotherms obtained for these samples were similar and they could be classified as type II according to IUPAC classification (Sing et al. 1985). Adsorption testing was conducted on clay-mudstone rock samples from Ordovician, Silurian and Carpathian Flysch layers. Sample selection was based on mineral content analysis outcome from quantitative X-ray analysis. The main selection criteria was calcium carbonate content, due to the fact that theoretically they do not undergo any transformations below 550°C, it turned out, however, that they might occur at much lower temperatures. At least 30 adsorption measurements were taken for each sample, totaling about 120 adsorption measurements. Cumulative curves were obtained together with pore volume distribution functions using BJH (BarrettJoyner-Halenda) (Barrett et al., 1951) algorithm from the desorption branch using Halsey’s statistical layer thickness equation and Faass (Faass, 1981) correction and also specific surface measurements (BET). Analysis of the obtained results allow us to conclude, that all samples should be put through the 0.5 mm sieve before analysis to minimize the error associated with its heterogenity. Later, after the sample has been preheated and Nitrogen vented in SmartPrep apparatus, it has to be cork sealed to eliminate secondary moisture adsorption. The consequence of preheating of a rock sample even at 65°C is the increase in its Vitrinite Reflectance by 3%, but after preheating it at 425°C, VR increases even by 500%. After adsorption analysis it was concluded that all the samples – regardless of whether their BET, change with temperature was positive or negative – showed local minima in 130–190°C and 360–425°C, and local maxima in 65–105°C and 250–320°C which phenomena should be examined in detail in further research, in order to analyse both physical and chemical processes present in similar trend in all analyzed samples.