Removal Of Carbon Disulfide Research Articles

Removal of carbon disulfide from air stream by absorption combined with electrochemical oxidation

The removal of carbon disulfide (CS2) in air stream by aqueous solution absorption combined with electrochemical oxidation was experimentally investigated. A rod-to-cylinder electrochemical oxidation reactor is employed for the experiment. The sample gas was introduced into the reactor from the bottom of the reactor and leaving from the upside of the reactor. It was found that the removal rate of CS2 in NaCl solution is higher than that in Na2SO4 solution. The removal of CS2 also depended on the applied current density and the pH value of the absorption solution. A maximum CS2 removal of about 40% was achieved in 0.05 mol·L−1 NaCl solution with a pH value of 4 and applied current density is 39 mA·cm−2. The final products of CS2 degradation were confirmed to be sulfate, carbon dioxide and a small amount of carbonyl sulfide.

Small-Scale Technology for Benzene Synthesis from Coke-Oven Gas

A small-scale production technology for benzene, toluene, xylenes, thiophene, saturated hydrocarbons, polymers, thiourea, and ammonium thiocyanate has been developed. The technology consists of three stages: 1) thermal polymerization of unsaturated compounds with simultaneous extraction of hydrogen sulfide from SB-1 crude benzene by ammonia and rectification to produce a benzene fraction, toluene, and a xylene blend; 2) removal of carbon disulfide and saturated compounds from the benzene fraction by adsorption; 3) removal of thiophene and unsaturated compounds from the benzene fraction by adsorption, to meet the standards of benzene for use in synthesis. In the first purification stage, ammonia produced in house at PAO Koks is employed. No wastes are formed in processing the crude benzene.

Low-temperature hydrolysis of carbon disulfide using the Fe[sbnd]Cu/AC catalyst modified by non-thermal plasma

The removal of carbon disulfide (CS2) from gas streams via FeCu/AC catalyst modified by non-thermal plasma (NTP) were investigated. In particular, effects of treatment conditions on the catalyst’s properties were studied. The properties change in the catalyst after NTP modification is measured by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and scanning electron microscope (SEM). The results showed relatively high capacities of FeCu/AC catalyst modified by NTP for removal of COS. The catalytic activity and sulfur capacity of material enhanced due to the extended oxygen functional groups on the surface of carbons. In addition, the surface area and micro-pore volume on NTP-modified catalysts played another important role in the process of CS2 removal.

Effects of Reaction Conditions on Low-Temperature Removal of Carbon Disulfide over Modified Coconut Shell Activated Carbons Catalysts

In this work, a series of modified coconut shell activated carbons (CSAC) catalysts were prepared by sol-gel method and used for catalytic hydrolysis of carbon disulfide (CS2) at low-temperatures. The influences of reaction conditions such as: reaction temperature, O2 concentration, relative humidity (RH), gas hourly space velocity (GHSV) and inlet concentration of CS2 on catalytic hydrolysis activities were studied. When the reaction temperature was 60°C, this catalyst showed the best catalytic performance and no better effect occurs with the increase of temperature. CS2 hydrolysis activities were decreased with increasing amounts of O2. When the RH was 30%, the catalyst manifests the best activity. The catalytic hydrolysis activities were decreased with increased of GHSV from 5000~20000h-1. In addition, when the inlet concentration of CS2 increased from 10ppm to 100ppm, the catalytic hydrolysis activities could be decreased.

Removal of Carbon Disulfide from Gas Streams Using Dielectric Barrier Discharge Plasma Coupled with MnO2 Catalysis System

The removal of gaseous carbon disulfide (CS2) via dielectric barrier discharge (DBD) combined with MnO2 catalysis has been investigated. CS2 removal and energy yield (EY) had been examined as a function of catalyzer position in DBD reactor, initial CS2 concentration, input power, and gas residence time. The results showed that DBD combined with MnO2 catalyst can improve the CS2 energy and removal efficiency, and MnO2 catalyst placed in afterglow area can enhance the CS2 removal efficiency by about 10 % as compared with DBD treatment only. When increasing initial CS2 concentration and flow rate, a higher EY is obtained. The possible CS2 removal pathways by DBD combined with MnO2 were proposed based on the product identification by FT-IR.

Removal of carbon disulfide: Experimental and modeling results

Abstract A mathematical model describing the rate of carbon disulfide (CS 2 ) removal has been developed. Kinetic studies were carried out in a fixed-bed reactor under atmospheric pressure and a range of temperatures (30–70 °C). The effects of flow rate, CS 2 inlet concentration, temperature and relative humidity were analyzed. A kinetic model based on axial dispersion, external and internal mass-transfer resistances, as well as effects of S deposition on the inner-face of the catalyst was in agreement with the CS 2 experimental breakthrough curves. The mathematical model can be used for process design and scale-up of similar systems.

Removal of carbon disulfide via coupled reactions on a bi-functional catalyst: Experimental and modeling results

A mathematical model describing the rate of carbon disulfide (CS 2) removal due to coupled reactions has been developed. Kinetic studies were carried out in a fixed bed reactor under atmospheric pressure and a range of temperatures (85–125 °C). The effects of flow rate, CS 2 inlet concentration, temperature and relative humidity were analyzed. A kinetic model based on axial dispersion, external and internal mass-transfer resistances, as well as effects of S deposition on the inner-face of the catalyst was in agreement with the CS 2 experimental breakthrough curves. The mathematical model can be used for process design and scale up of similar systems.

Removal of carbon disulfide (CS 2) from water via adsorption on active carbon fiber (ACF)

The primary objective of this paper was to demonstrate the suitability of ACF in effectively adsorbing CS 2 from water, and to compare its performance vs. that of GAC. Commercial ACF was modified to increase its specific surface and pore volume. CS 2 removal was studied by adding ACF to water containing CS 2 under varying conditions. The experimental results reveal that ACF is a potential adsorbent for capturing CS 2 under both equilibrium and dynamic adsorption/desorption conditions. The adsorption capacity of ACF was observed to considerably increase with the increase of CS 2 concentration: It was observed that the modified ACF exhibited greater adsorption for CS 2 than the GAC, and the mechanism for this difference was explored; The modified ACF showed a consistent performance within a pH range from 3–9; Under the experimental conditions, an modified ACF sample was adsorbed and desorbed by boiling water repeatedly without exhibiting any appreciable degradation in its adsorption performance.

A technique for the specific cleavage of arginyl bonds by trypsin

A method is presented for limiting the action of trypsin on proteins and peptides to hydrolysis of bonds involving the carboxyl groups of arginine. Lysine side chains are modified by reaction with carbon disulfide to form the dithiocarbamyl derivative. Bonds involving this residue are no longer susceptible to digestion by trypsin. This procedure was carried out both with a 20-amino acid peptide obtained from the limited digestion of RNAase with subtilisin (RNAase-S-peptide) and with reduced alkylated egg-white lysozyme. With both molecules it was demonstrated that the carbon disulfide could be easily removed and hydrolysis by trypsin of the bonds involving lysine could then be carried out. Confirmatory amino acid-composition studies were carried out on the products of digestion by trypsin of the RNAase-S-peptide, with and without carbon disulfide modification. The peptides produced by tryptic digestion of carbon disulfide-modified egg-white lysozyme were separated by ion-exchange column chromatography after removal of carbon disulfide. All of the peptides obtained were then individually redigested with trypsin and 8 of them gave 2 or more products which differed in electrophoretic mobility from their parent peptides, and which, unlike the latter, could be found in a control tryptic digest of unmodified egg-white lysozyme. This method is suggested as a means of easily obtaining part of the information required to arrange the tryptic peptides of a protein in order.