Ethylenediamine Vapor Research Articles

Conductometric Gas Sensor Based on MoO3 Nanoribbon Modified with rGO Nanosheets for Ethylenediamine Detection at Room Temperature.

An ethylenediamine (EDA) gas sensor based on a composite of MoO3 nanoribbon and reduced graphene oxide (rGO) was fabricated in this work. MoO3 nanoribbon/rGO composites were synthesized using a hydrothermal process. The crystal structure, morphology, and elemental composition of MoO3/rGO were analyzed via XRD, FT-IR, Raman, TEM, SEM, XPS, and EPR characterization. The response value of MoO3/rGO to 100 ppm ethylenediamine was 843.7 at room temperature, 1.9 times higher than that of MoO3 nanoribbons. The MoO3/rGO sensor has a low detection limit (LOD) of 0.235 ppm, short response time (8 s), good selectivity, and long-term stability. The improved gas-sensitive performance of MoO3/rGO composites is mainly due to the excellent electron transport properties of graphene, the generation of heterojunctions, the higher content of oxygen vacancies, and the large specific surface area in the composites. This study presents a new approach to efficiently and selectively detect ethylenediamine vapor with low power.

Detection of Ethylenediamine Vapor by Optical Waveguide Sensor Based on Tetrakis-Carboxylphenyl Porphyrin Film

A sensitive element was prepared by the spin coating method on the surface of a K+ exchange glass optical waveguide by dissolving tetrakis-carboxyphenyl porphyrin (TCPP) in the nontoxic solvent ethanol. The TCPP sensitive element detected 18 volatile organic compounds with an excellent selective response to ethylenediamine (EDA) gas. On this basis, the effects of the solvent, solution mass fraction, speed of the homogenizer and atmospheric humidity on the detection of EDA gas by the sensitive element were discussed. The formation of hydrogen bonds between TCPP and EDA molecules is proposed, which leads to changes in the morphology and light absorbance of the sensing film.

Gas phase infrared spectroscopy of the H2C NH2+ methaniminium cation

Abstract The methaniminium ion (H2C NH2+) was produced in a pulsed electrical discharge supersonic expansion of argon saturated with ethylenediamine vapor. It was identified and mass selected in a time-of-flight spectrometer. Its infrared spectrum was measured in the region of 2100–4100 cm−1 by photodissociation of the argon-tagged complex with a tunable infrared OPO/OPA laser system. The observed infrared spectrum was not described well by scaled harmonic theory, but could be assigned by comparison to second order vibrational perturbation theory computations at the B2PLYP/def2-QZVPP level.

Developing a new method for synthesizing amine functionalized g-C3N4 nanosheets for application as anti-corrosion nanofiller in epoxy coatings

In this research, the effect of graphitic carbon nitride (g-C3N4) on the corrosion protection performance of solvent-based epoxy coatings is investigated. The g-C3N4 is synthesized by two-step condensation of melamine and is characterized by X-ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy, and carbon–hydrogen–nitrogen elemental analysis. In order to enhance the dispersion of g-C3N4 in epoxy coating, it is chemically functionalized with ethylenediamine vapor via a simple method. Further, epoxy coatings containing different amounts (0, 0.05, 0.1, 0.3, 0.5, and 0.7 wt%) of amine functionalized g-C3N4 (AF g-C3N4) are spray coated on mild steel substrate. The dispersion quality of nanofillers in coating matrix is studied by field emission scanning electron microscopy. The corrosion resistance of samples is investigated by electrochemical impedance spectroscopy. The results reveal the superior corrosion protection of nanocomposite coatings due to barrier performance of AF g-C3N4. Meanwhile, epoxy coating containing 0.5 wt% AF g-C3N4 shows the highest corrosion protection compared to pure epoxy sample.

Highly responsive ethylenediamine vapor sensor based on a perylenediimide–camphorsulfonic acid complex via ionic self-assembly

Two perylene conductometric sensors with excellent selectivity and low detection limit towards ethylenediamine vapor have been developed by ionic self-assembly.

Surface Cross-Linking of ZIF-8/Polyimide Mixed Matrix Membranes (MMMs) for Gas Separation

The demand for cost-efficient separations requires membranes with high gas flux and high selectivity which opens the path for further improvements. Mixed matrix membranes (MMMs) made from 33.3 wt % ZIF-8 in 6FDA-durene were tested at 35 °C and 3.5 atm. At 33.3 wt % loading of ZIF-8, H2, N2, O2, and CH4 gas permeabilities increased approximately 400%. Cross-linking the surface of this MMM, by reacting with ethylenediamine vapor, yielded a 10-fold increase in H2/CO2, H2/N2, and H2/CH4 selectivities with respect to 6FDA-durene, preserving 55% of the H2 permeability of 6FDA-durene. The permselective properties of the cross-linked skin of the MMM fall above the most recent permeability–selectivity trade-off lines (2008 Robeson upper bounds) for H2/CO2, H2/N2, and H2/CH4 separations. To the best of our knowledge, this is the first example of a cross-linked ZIF/polymer MMM for gas separation.

Direct Synthesis of B−C−N Single-Walled Nanotubes by Bias-Assisted Hot Filament Chemical Vapor Deposition

Direct synthesis of large-scale ternary boron carbonitride single-walled nanotubes (BCN-SWNTs) via a bias-assisted HFCVD process was presented. The BCN-SWNTs were grown over the powdery Fe-Mo/MgO catalyst by using CH4, B2H6, and ethylenediamine vapor as the reactant gases. As high as 16 atom % nitrogen can be incorporated within the nanotube shells, with the boron content in the range of 2-4 atom %. The ternary covalent bonding nature of the BCN-SWNTs was well characterized, and the B, C, and N elemental maps were clearly imaged by energy-filtered transmission electron microscopy.

Preparation of uniform spherical titania particles coated with polyurea by the aerosol technique

The aerosol technique has been employed in the preparation of uniform colloidal inorganic particles coated with an organic polymer. Specifically, spherical titania cores were produced first by hydrolysis of Ti(IV) ethoxide droplets in contact with water vapor. Hexamethylenediisocyanate liquid was then condensed on these particles and exposed to ethylenediamine vapor. By varying experimental conditions (temperature and flow rate) one attained uniform coatings of polyurea of different thickness on titania.

Evaluation of Some Regenerate Sulfur Dioxide Absorbents for Flue Gas Desulfurization

The body of information presented in this paper is directed to chemical engineers in the field of environmental control technology. The vapor pressure of sulfur dioxide above aqueous solutions of citric acid, glycolic acid, 1-methyl-2-pyrrolidone, and ethylenediamine, as well as above pure tri-n-butyl phosphate, 1-methyl-2-pyrrolidone, and water were measured for possible application as absorbents for regenerable flue gas desulfurization systems. Results were used to estimate the steam rate and principal costs of processes using 11 of the absorbents. For sulfur dioxide absorption followed by indirect steam stripping, a 9.75 % ethylenediamine solution had the lowest steam rate. The ethylenediamine steam rate was 25% of the next two lowest steam rates, which were for pure l-methyl-2-pyrrolidone and citric acid solution. However, cost of losses of ethylenediamine vapor up the stack were excessive, indicating that a higher boiling point amine would be preferable.