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Preparation and Characterization of Porous Carbon/RDX Nanocomposite Energetic Materials

Jiang Ju, Su Jin-Xiao, Liu Zhi-Tao, Du Ping, Liao Xin, Li Xiao-An

Central European Journal of Energetic Materials

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2023

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Vol. 20, no. 3

284--301

EN

A novel energetic material was fabricated by filling porous carbon with 1,3,5-trinitro-1,3,5-triazinane (RDX) via the ultrasonic stirring method. Characterization (TEM, BET, XRD, FTIR, etc.) was performed to determine the micromorphology, crystal structure, and specific surface area. TEM images indicated that the RDX particles were homogeneously distributed in the channels of the porous carbon, FTIR spectra and the XRD curve of the C/RDX composite exhibited the combined characteristics of porous carbon and RDX. The BET test data also confirmed this situation. The thermal decomposition kinetics and thermodynamics of the C/RDX nanocomposite energetic material were investigated at various heating rates (5, 10, 15, and 20 K·min⁻¹). The test results showed that the thermal decomposition temperature and the critical temperature of thermal explosion were lower than for RDX alone by 46.8 and 40.69 ℃, respectively. The activation energy of the C/RDX composite was lower than those of raw RDX and a C/RDX physical mixture, indicating that the C/RDX composite exhibited high thermolysis activity.

2

Właściwości porowatych materiałów węglowych otrzymywanych metodą mechanochemiczną

Borysiuk Sylwia, Szczęśniak Barbara, Choma Jerzy, Jaroniec Mieczysław

Wiadomości Chemiczne

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2020

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[Z] 74, 5-6

339-369

EN

Most methods used for the synthesis of functional nanomaterials contribute to the increasing amount of waste solvents. An environmentally friendly solution of this issue is the utilization of “green” procedures for a large-scale production of materials such as mechanochemical synthesis. Although, the beginnings of mechanochemistry date back to ancient times, it nowadays experiences a renaissance and attracts a lot of attention. Recently, mechanochemistry has been successfully implemented for the synthesis of diverse carbonaceous materials, i.e., activated carbons, ordered mesoporous carbons, graphene-based materials and carbon nanotubes, the usage of which ranges from adsorption, catalysis to environmental and energy storage applications. Undoubtedly, it becomes quite universal and powerful synthesis method. Hence, a review summarizing the current accomplishments in this field is needed.

3

Badania kinetyczne adsorpcji wybranych barwników z roztworów wodnych na nanoporowatych węglach aktywnych otrzymanych z prekursorów polimerowych

Czubaszek M., Choma J.

Ochrona Środowiska

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2016

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Vol. 38, nr 4

3--12

PL

Badano kinetykę adsorpcji wybranych barwników (oranż kwasowy 7, oranż kwasowy 52 i błękit zasadowy 9) z roztworów wodnych na trzech porowatych adsorbentach. Dwa z nich stanowiły proszkowe węgle otrzymane laboratoryjnie z prekursorów polimerowych, natomiast trzeci – zastosowany w celach porównawczych – był handlowym węglem aktywnym firmy Chemviron Carbon. Pierwszy adsorbent laboratoryjny był węglem aktywnym ze znaczną objętością mikroporów, otrzymanym z sulfonowej żywicy styrenowo-dwuwinylobenzenowej. Drugi był natomiast uporządkowanym mezoporowatym węglem otrzymanym z żywicy fenolowo-formaldehydowej metodą miękkiego odwzorowania. Do opisu kinetyki procesu adsorpcji barwników wykorzystano równania pseudo I i pseudo II rzędu. Stwierdzono, że adsorpcja wybranych barwników na badanych węglach aktywnych przebiegała zgodnie z modelem pseudo II rzędu, o czym świadczyły wartości współczynnika korelacji bliskie 1. Wykazano, że kinetyka adsorpcji na poszczególnych węglach różniła się istotnie – stan równowagi adsorpcyjnej osiągany był najszybciej (kilka minut) na węglu aktywnym z sulfonowej żywicy styrenowo-dwuwinylobenzenowej, natomiast najwolniej (kilka godzin) na węglu handlowym. Badane węgle także istotnie różniły się pojemnością adsorpcyjną – najlepszą charakteryzował się węgiel aktywny otrzymany z sulfonowej żywicy styrenowo-dwuwinylobenzenowej. Wymagana dawka tego węgla w celu usunięcia 100% barwnika z roztworu o stężeniu 150 mg/dm3 wynosiła 400 mg/dm3, natomiast w przypadku pozostałych dwóch węgli była pięciokrotnie większa.

EN

Adsorption kinetics of the selected dyes (Acid Orange 7, Acid Orange 52 and Basic Blue 9) from aqueous solutions were studied on three porous materials. Two of them were laboratory powdered carbons obtained from polymeric precursors, while the third one was a commercial micro-mesoporous activated carbon from Chemviron Carbon, used for reference purposes. The first laboratory adsorbent was an active carbon with a high micropore volume, synthesized from the sulfonated styrene-divinylbenzene resin. The second one was an ordered, mesoporous carbon obtained from phenol-formaldehyde resin by soft-templating. The adsorption kinetics data was illustrated using the pseudo-first and pseudo-second order models. The correlation coefficient values close to unity proved that adsorption of selected dyes on the studied active carbons proceeded according to the pseudo-second order model. It was demonstrated that the adsorption kinetics differed significantly between the studied materials. The active carbon obtained from the sulfonated styrene-divinylbenzene resin was the quickest (minutes) to reach the adsorption equilibrium, while the commercial one was the slowest (hours). Additionally, the studied carbons displayed significantly different adsorption capacities. The activated carbon obtained from the sulfonated styrene-divinylbenzene resin was the best adsorbent and 400 mg/dm3 was a dose sufficient to remove 100% of the dye from 150 mg/dm3 solution. For the remaining two carbons that dose was five times higher.

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Adsorption of humic acid on mesoporous carbons prepared from poly- (ethylene terephthalate) templated with magnesium compounds

Karolczyk J., Mozia S., Morawski A. W., Przepiórski J.

Polish Journal of Chemical Technology

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2012

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Vol. 14, nr 4

95-99

EN

Porous carbons obtained from poly(ethylene terephtalate) contained in a mixture with either MgCO3 or Mg(OH)2 were examined as adsorbents for removal of humic acid from water. Adsorption of the model contaminants is discussed in relation to the textural parameters of the obtained carbon materials. Pore structure parameters of the carbonaceous materials were strongly influenced by preparation conditions including temperature and relative amounts of the inorganics used during preparations as template. Porous carbons prepared revealed a potential to purify water from the model contaminant of high molecular weight. The results presented confirmed a key role of mesoporosity in the adsorption of humic acid. Fluorescence spectroscopy was confirmed to be an useful method to evaluate concentration of humic acid in water.

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The simplex optimization for high porous carbons preparation

Sreńscek-Nazzal J., Michalkiewicz B.

Polish Journal of Chemical Technology

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2011

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Vol. 13, nr 4

63-70

EN

The microporous carbon materials were prepared by chemical activation of Polish coal with potassium hydroxide using the simplex design method for planning the experiments. The experimental parameters were varied to identify the optimum conditions. Coal can be an excellent starting material for the preparation of high porous carbons for natural gas storage. The porosity of the resultant carbons was characterized by nitrogen adsorption (-196oC). Methane adsorption was investigated in a volumetric laboratory installation at range pressures from 1 to 3.5 MPa (25oC). The best results of methane storage capacity (557 cm3 . g-1) were obtained when using an impregnation ratio 3.41/1 KOH/precursor and temperature at 592oC, (SLANG = 2091 m2 . g-1). The parameters of the preparation of high porosity and high methane adsorption carbon were determined by a fast and simple method.

6

Preparation and properties of porous carbon material containing magnesium oxide

Przepiórski J., Czyżewski A., Kapica J., Casa-Lillo M. A. de la

Polish Journal of Chemical Technology

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2011

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Vol. 13, nr 4

42-46

EN

Porous carbons loaded with magnesium oxide were prepared through one-step process. Poly(ethylene terephthalate) and natural magnesite were used as carbon source and MgO precursor, respectively. An impact of a temperature and relative amounts of raw components used for preparations on the textural parameters of resulting hybrid materials is presented and discussed. As found, pore structure parameters tend to decrease along with MgO loading and temperature used during preparation process. Micropore area is the parameter being reduced primarily.

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Porous carbons from Novolac resin activated with solid NaOH

Pająk J., Łabojko G., Lachowski A.

Polish Journal of Applied Chemistry

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2007

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Vol. 51, nr 1-2

43-48

EN

Microporous carbons were prepared from Novoiac resin acti\ cited in the reaction with solid NaOH . The effects of activation temperature and time and the NaOH/resin ratio on the porosity were studied. It was shown that the changes in the reaction temperature (within 600-800°C) and reaction time had no significant effect on the porosity whereas NaOH/resin ratio had strong effect on the porosity. The ratio of 2:1 appeared to be the most appropriate for obtaining highly porous carbons. The influence of HMTAused for Novoiac curing on the yield and the characteristics of activated carbon was also investigated. The curing before activation increased the yield of final product without decreasing its porosity.