High-Pressure Phase Equilibria in Systems Containing CO2 and Ionic Liquid of the [Cnmim][Tf2N] Type

In this review, we present a comparison of the high-pressure phase behaviour of binary systems constituted of CO2 and ionic liquids of the [Cn(m)mim][Tf2N] type. The comparative study shows that the solubility of CO2 in ionic liquids of the [Cnmim][Tf2N] type generally increases with increasing pressure and decreasing temperature, but some peculiarities have been observed. The solubility of CO2 in ionic liquid solvents was correlated using the Soave–Redlich–Kwong equation of state. The results of the correlation were analysed by methods of mathematical gnostics. It was proved that the application of this equation of state is sufficient for testing the mutual agreement or disagreement of experimental data of the solubility of carbon dioxide in ionic liquids

Excess Molar Volume of Binary Systems Containing Mesitylene

This paper presents a review of density measurements for binary systems containing 1,3,5-trimethylbenzene (mesitylene) with a variety of organic compounds at atmospheric pressure. Literature data of the binary systems were divided into nine basic groups by the type of contained organic compound with mesitylene. The excess molar volumes calculated from the experimental density values have been compared with literature data. Densities were measured by a few experimental methods, namely using a pycnometer, a dilatometer or a commercial apparatus. The overview of the experimental data and shape of the excess molar volume curve versus mole fraction is presented in this paper. The excess molar volumes were correlated by Redlich–Kister equation. The standard deviations for fitting of excess molar volume versus mole fraction are compared. Found literature data cover a huge temperature range from (288.15 to 343.15) K

Ekscesni molarni obujam binarnih sustava koji sadrže mezitilen

This paper presents a review of density measurements for binary systems containing 1,3,5-trimethylbenzene (mesitylene) with a variety of organic compounds at atmospheric pressure. Literature data of the binary systems were divided into nine basic groups by the type of contained organic compound with mesitylene. The excess molar volumes calculated from the experimental density values have been compared with literature data. Densities were measured by a few experimental methods, namely using a pycnometer, a dilatometer or a commercial apparatus. The overview of the experimental data and shape of the excess molar volume curve versus mole fraction is presented in this paper. The excess molar volumes were correlated by Redlich–Kister equation. The standard deviations for fitting of excess molar volume versus mole fraction are compared. Found literature data cover a huge temperature range from (288.15 to 343.15) K.U ovom je radu dan pregled izmjerenih gustoća binarnih sustava koji sadre 1,3,5-trimetilben-zen (mezitilen) s različitim organskim spojevima pri atmosferskom tlaku. Literaturni podaci o binarnim sustavima razvrstani su u devet osnovnih skupina prema vrsti organskog spoja u smjesi s mezitilenom. Ekscesni molarni obujmi izračunati su iz eksperimentalno određenih vrijednosti gustoće i uspoređeni s literaturnim podacima. Gustoće su izmjerene pomoću nekoliko eksperimentalnih metoda: piknometrom, dilatometrom ili nekom od komercijalnih aparatura. Prikazani su eksperimentalni podaci i oblik krivulje ekscesnog molarnog obujma u ovisnosti o molnom udjelu. Procijenjene vrijednosti ekscesnih molarnih obujama u ovisnosti o molnom udjelu korelirane su Redlich-Kisterovom jednadžbom, a prikladnost odabrane funkcije izražena je usporedbom standardnih devijacija. Literaturni podaci pokrivaju široko temperaturno područje (od 288,15 do 343,15 K).</p

Changes in soil carbon and nitrogen accessibility with the application of biochars with different morphological and physical characteristics

Purpose The recent literature indicates that, depending on the feedstocks and pyrolysis temperature, biochar can be a good source of nutrients. On the contrary, some biochars are not good sources of available carbon and other nutrients, but their porous structure seems to be a suitable microenvironment for microbial colonization. We investigated the response of soil biological parameters, microbial biomass carbon and nitrogen (MBC and MBN), in relation to mobile N species. Material and methods Five different biochars were produced at different temperatures (300, 350, 400, 450, and 500 °C) from the same feedstock (woodchips). The physicochemical and morphological characteristics of the individual biochar samples were described, and incubation was carried out with the application of 2% biochar to two different soil types (luvisol and fluvisol). Results and discussion The addition of 2% biochar did not change the pH in the slightly acid soils used in the experiment, in spite of the alkaline character of biochar. The increasing amounts of total and nitrate-available nitrogen during the experiment are probably related to changes in soil microbial activity. The amount of soluble carbon was constant during the experiment, confirming its stability in the soil, most likely because of the high amount of lignin in the feedstock. The influence of biochar on the soil microbiome was determined on the basis of the concentrations ofMBC andMBN. Microbial biomass was increased in both soils treated with biochar produced at lower temperatures. Conclusions The physicochemical characteristics of the biochar as well as the sorption behavior of N-NO3 − and N-NH4 + indicate that at a pyrolysis temperature of 400 °C, biochar properties change substantially. However, these findings are only valid for biochar produced from woodchips, and the long-term effects of biochar application on soil properties need to be investigated in further studies

Structure of montmorillonite cointercalated with stearic acid and octadecylamine : modeling, diffraction, IR spectroscopy

Structural analysis of Na-montmorillonite co-intercalated with octadecylamine and stearic acid was carried out using combination of experiment: X-ray powder diffraction and IR spectroscopy with molecular modeling (force field calculations) in Cerius2 modeling environment. Results of structure analysis revealed the chemical reaction of guest compounds leading to the formation of octadecylammonium stearate. This reaction may occur even before the intercalation out of the interlayer space of montmorillonite. The presence of octadecylammonium stearate in the samples was clearly confirmed by IR spectroscopy and X-ray diffraction. Present results also showed that: (1) Stearic acid itself does not intercalate into Na-montmorillonite; (2) cointercalation with octadecylamine led to the formation of octadecylammonium stearate, which was successfully intercalated into the interlayer space of montmorillonite, and (3) Na-montmorillonite intercalated with octadecylammonium stearate does not create a stable structure. Intercalated samples in ambient conditions undergo gradual decomposition, accompanied by the release of octadecylammonium stearate from the interlayer space and rearrangement of the interlayer structure. Co-intercalation of STA and ODA to lower the octadecylamine content and consequently to suppress the unfavorable effect of amine groups on the polymer matrix in nanocomposite, was investigated