Coke and Chemistry最新文献

Pitch-like products play an important role in the production of carbon fibers, electrodes, and other carbon items. The production of pitch-like products from G, Zh, and GZh coal by thermal solution is considered. The solvent is anthracene oil derived from coal tar. The characteristics of the pitch-like products are determined.

The possibility of extracting vanadium from various carbon materials (petroleum coke, bitumen, fuel-oil ash and slag, ash from foundry graphite, black shale, and lignite) is investigated. Systems for producing vanadium slag from ash and from titanomagnetite ore are compared. The two types of slag are compared in terms of phase composition, chemical composition, and content of soluble forms of vanadium. In experimental melts, a vanadium alloy and vanadium slag are obtained. The potential for extracting vanadium from carbon materials is demonstrated.

The adsorption of aniline from aqueous solution on carbon sorbents is investigated. The sorbents are derived from D and G Kuznetsk Basin coal by chemical activation using potassium hydroxide at 800°C, when the coal/alkali ratio (by mass) is 1.0 : 0.5 and 1.0 : 1.0. The sorbents consist mainly of micropores, and their specific surface is relatively high (700–1340 m²/g). The experimental adsorption isotherms are plotted. On that basis, the parameters of the Langmuir, Freundlich, Dubinin–Astakhov, and BET sorption models are calculated. The models are appropriate for the description of aniline adsorption (R² > 0.9). The Langmuir model is the most accurate. The state parameters indicate that the adsorption of aniline by this means is very effective. The process may be described as monomolecular adsorption on the surface of microporous sorbents. The thermomechanical characteristics of the adsorption process are low. That indicates physical adsorption.

The treatment of mine wastewater is of great environmental importance. Treatment systems including sorption on activated carbon are widely used. The sorbents employed require periodic regeneration. That interrupts the wastewater flow. The solution is to use a battery of sorbent modules, which are regenerated in turn. Thus, the battery will always include a module that is being regenerated. The operating time of the sorbent modules without regeneration may be increased at no cost to treatment quality if the wastewater flow rate is decreased as the sorbent becomes saturated. However, this approach changes the overall productivity of the system. Accordingly, an automated system must be developed to monitor and regulate the distribution of the wastewater flow among the modules in the battery, taking account of the level of sorbent saturation in each one. The proposed automated system employs no less than five sorbent modules. The control algorithm ensures periodic shutdown of each of the modules for regeneration. The control system for each module adjusts the wastewater flow in accordance with its level of sorbent saturation.

One- and two-dimensional models are employed to determine how the heating wall temperature of a furnace chamber within a coke battery affects the coke quality. The half-width b of the chamber is considered as a secondary factor. One- and two-dimensional thermal models of coking permit the prediction of coke quality. The results are verified by means of production data for Moscow Coke and Gas Plant (Moskoks). The optimal coking temperatures are determined on the basis of the one- and two-dimensional models of the coke oven.

The organic mass of coal from different fields is studied by X-ray diffraction. On the X-ray diffraction patterns, the amorphous carbon structure of the coal mainly corresponds to broad intense peaks due to its disordered stacking, with narrow peaks corresponding to the mineral component. X-ray analysis permits not only diagnostics of any carbon component but also determination of the dynamics and mechanism of phase transformations in carbon systems under the action of physicochemical factors. The mineral component of the coal mainly consists of oxidized silicon. Calcium is present in the coal’s organic mass. Iron and aluminum appear partially as organomineral compounds in mineral inclusions. The goal of the research is to select the optimal coal for the production of specialized activated carbon additives that may be used in the thermal hydrocracking of heavy oil-refining residues. These additives must meet requirements on their mineral composition and chemical structure.

The action of nanosecond laser pulses (wavelength 532 nm, pulse length 14 ns, pulse repetition rate 6 Hz, energy density of laser radiation 0.2–0.6 J/cm²) in G and Zh coal pellets is investigated, in an argon atmosphere. The gaseous products of sample pyrolysis include H₂, CH₄, C₂H₂, CO, and CO₂. The content of the gaseous components is determined as a function of the laser energy density. In the range 0.2–0.4 J/cm², the volume of flammable gases formed (referred to the mass loss of the sample) increases; at higher energy densities, practically no change in volume is observed. The gross calorific value of the flammable gases increases linearly from ~8–10 to 19 MJ/m³ with increase in energy density of the laser radiation from 0.2 to 0.6 J/cm². A nanosecond pulse of energy density more than 0.4 J/cm² results in intense ablation of the pellets containing 0.005 wt % polyvinyl alcohol. The coal pellets that contain no binder break down under the action of a nanosecond laser pulse of energy density exceeding 0.2 J/cm².