Oxidized coal as a sorbent for softening water

Sorption tests carried out oxidized nitric acid active carbon in H+- and Na+- form in relation to cations Mg2+ and Ca2+ and mixture thereof. Values obtained statistical volumetric capacity samples and mass loss them during processing nitric acid, that is oxidation state. Discovered correlation between these data and relevant sorption volume samples. Demonstrated a possible water softening oxidized coal subject to specific solution acidity.

Neutralization of solvent vapors of brand 650 by the adsorption‑catalytic method

The purpose of this work is to study the process of neutralization of vapors of a mixed solvent of the brand 650 by the adsorption‑catalytic method. The essence of the method consists in the concentration of solvent components on the sorbent, thermal desorption followed by periodic flameless catalytic oxidation of accumulated organic substances to carbon dioxide and water. Synthetic zeolite of the NaX brand was used as a sorbent, and a porous material based on foam ceramics of the Al2O3/SiO2 composition with a highly developed modified surface with an active catalytic phase was used as a catalyst. The mixed solvent contains, xylenes, ethylcellosol, n‑butanol. It is shown that the value of the sorption volume of zeolite for each class of the considered compounds is influenced by certain factors: the length and structure of the carbon skeleton, the position of the hydroxyl group (for alcohols and esters), the number of methyl groups in the composition of molecules (for the production of benzene). The conversion rate of the mixed solvent components was 65.4–90.1 %.

Influence of moisture content on NO2 sorption ability of cedar wood

This study examined the influence of moisture content (MC) on NO2 sorption ability of cedar (Cryptomeria japonica) wood using the specimens with different MCs. Four MC conditions were applied, namely 0%, 8.6%, 12.7% and 16.5%, based on the differences of bonding condition of water molecule in the wood substances. As a result, the NO2 sorption volume increased drastically due to the presence of water, and as the MC increased, the NO2 sorption volume increased slightly. The NO generation volume and nitric acid concentration in the specimens were evaluated after an aeration test, and it was strongly indicated that the NO2 reacted with water in the specimen, and that the NO generation volume increased as the content of multilayer adsorbed water increased. The nitric acid seemed to be formed by the reaction between NO2 and water, and it was then held in the specimen. Based on the NO2 sorption volume calculated using the NO generation volume, it was shown that the NO2 sorption after 12-h aeration was caused mainly by the reaction between NO2 and water. Furthermore, the presence of both water and extractives contributed to the NO2 sorption in the initial period, and the presence of water contributed greatly to the NO2 sorption over the long term.

Neutralization of solvent vapors of brand 646 by the adsorption-catalytic method

The aim of the paper is investigation of neutralization of solvent vapors of the brand 646 by an adsorption-catalytic method. The adsorption-catalytic method includes the following stages: adsorption of the solvent components by adsorbent, thermal desorption and periodic flameless catalytic oxidation of organic substances to carbon dioxide and water. Synthetic zeolite of the NaX brand was used as a sorbent, catalyst was porous Al2O3/SiO2 ceramic foam material with an active catalytic phase. Solvent contains aceton, toluene, butylacetate, ethanol, ethyl cellosolve, n-butanol. It is shown that the value of the sorption volume of zeolite for each class of compounds depends on the certain factors: the length and structure of the carbon skeleton, the position of the hydroxyl group (for alcohols and esters), number of methyl groups in the molecules (for benzene derivatives). The conversion of the mixed solvent components was 65.4–90.1 %.

Adsorption properties of benzene vapors on activated carbon from coke and asphalt

The industry produces a variety of wastes in production processes. This has a negative impact on the state of ecological balance. Today, in the oil industry, many different types of oil waste are accumulated as reserves. Focusing them on targeted production is one of the most pressing issues today. The use of a high-vacuum adsorption device is important in producing adsorbents from coke and asphalt from residual oil products and in the complete determination of the sorption properties of the obtained adsorbents. Benzene and toluene adsorption isotherms, the sorption volume, and properties of the new adsorbent can be described in detail by studying the adsorption heat.

Bitemplate Synthesis of Mesoporous Silicas with Thiourea Groups

Mesoporous silicas with the thiourea functional group ≡Si(CH2)3NHC(S)NHC2H5 have been synthesized by monotemplate and bitemplate route (bitemplate is cetylpyridinium chloride as micelle-forming surfactant and monoethanolamide of saturated n-aliphatic acid as non-micelle-forming surfactant). The infl uence of a number of factors on mesoporous silicas structure has been studied: alkoxysilanes and surfactants concentration, and as well as the nature of medium in hydrothermal treatment of mesophases. The optimum conditions under which functionalized mesoporous silicas have possessing highly ordered hexagonal structure have been found. The surface area of mesoporous silicas synthesized using optimum bitemplate solubilization composition reaches 1055-1350 m2/g and sorption volume and pore diameter are 0.75-0.95 cm3/g and 2.5-2.9 nm respectively.

Dependence of the C Constant in the Brunauer-Emmett-Teller Equation on Water Pre-Adsorbed on Activated Carbon

The dependence of the C constant in the BET equation on the amount of pre-adsorbed water has been investigated by low-temperature nitrogen adsorption on activated carbon containing different amounts of water pre-adsorbed at the same relative water vapour pressure. It is suggested that the rapid decrease in the surface area as determined by the BET method in comparison with the C value in cases of low degrees of sorption volume filling is associated with blocking of part of the carbon texture and the parallel formation of extremely narrow micropores.