Cu/HZSM-5 Sorbent Treated by NH₃ Plasma for Low-Temperature Simultaneous Adsorption–Oxidation of H₂S and PH₃

Abstract

In this study, an NH3 plasma-treated Cu/HZSM-5 sorbent was introduced to simultaneously remove H2S and PH3 in low-temperature and low-oxygen environments. The effects of the Cu loading amounts, modification methods, and plasma-treatment conditions on the adsorption–oxidation performance of the sorbents were investigated. From the performance test results, the sorbent treated by NH3 plasma with the specific energy input (SEI, electrical input energy to the unit volume of gas) value of 1 J·mL–1 (Cu/HZSM-5-[S1]) was identified as having the highest breakthrough capacities of 108.9 mg S·g–1 and 150.9 mg P·g–1 among all of the materials tested. After three times of regeneration, the sorbent can still maintain the ideal performance. The results of Fourier transform infrared (FT-IR) spectroscopy and CO2 temperature-programmed desorption (CO2-TPD) indicated that the NH3 plasma treatment can introduce amino groups (functional groups) onto the sorbent surface, which greatly increases the number and strength of the basic sites on the sorbent surface. Results of N2 adsorption/desorption isotherms and scanning electron microscopy–energy dispersive spectroscopy (SEM–EDS) showed that the morphology of the sorbent changed after the plasma treatment, which exposed more active sites (copper species). In situ IR spectra showed that the amino groups are continuously consumed during the reaction process, indicating that these amino groups can help sorbents to capture gas molecules. Moreover, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analyses indicated that CuO is the main active species and the consumption of CuO and accumulation of the reaction products on the surface and inner pores of the sorbent are the primary reasons for the deactivation of the sorbent.

Unveiling the Potential of Novel Struvite–Humic Acid Composite Extracted from Anaerobic Digestate for Adsorption and Reduction of Chromium

“…The specific surface area and average diameter of the pores of HA were 5.1 m 2 g −1 and 10.25 nm, respectively, which was lower than for S-HA (19.3 m 2 g −1 and 4.3 nm, respectively). These findings indicated that the struvite coated on the surface of HA affected the physical properties and pore structure of the S-HA, thus increasing the complexing capacity of S-HA [33].…”

“…The specific surface area and average diameter of the pores of HA were 5.1 m 2 g −1 and 10.25 nm, respectively, which was lower than for S-HA (19.3 m 2 g −1 and 4.3 nm, respectively). These findings indicated that the struvite coated on the surface of HA affected the physical properties and pore structure of the S-HA, thus increasing the complexing capacity of S-HA [33]. Moreover, the specific surface area and average pore diameter of HA and S-HA were estimated based on the N 2 adsorption/desorption isotherms combined with Brunauer-Emmett-Teller (BET) multilayer adsorption theory (Figure S2).…”

One-Step Synthesis of Ammonia Directly from Wet Air/N2 by Plasma Combined with a γ-Al2O3 Catalyst

“…32 The extra energetic electrons do not participate in effective collisions, so the energy is wasted, and the energy efficiency is reduced in the discharge process. In addition, NH 3 molecules are reported to be dissociated in the plasma environment, 40 suggesting that high SEI may cause the generated NH 3 to be decomposed again, thus reducing the system's energy efficiency. Plasma catalytic coupling is a very sophisticated system in which the ammonia formation rate and energy efficiency are affected by the plasma reactor (type, size, material, and structure), discharge parameter (voltage, frequency, energy density, etc.…”

Effect of Catalytic Factors of Activated Carbon and Gas Stream Properties on H2S Catalytic Conversion

“…The exposed concentration beyond 500 ppm causes a loss of consciousness (Azargohar et al 2011). The conventional methods for H 2 S treatment contain the biological treatment (Barbusinski et al 2021), wet scrubbing (Wang et al 2020), low temperature plasma technology (Feng et al 2021), advanced oxidation (Gao et al 2022), special activated carbon adsorption (Ning et al 2018;Shen et al 2018;Li et al 2022). Among these methods, adsorption is one of the most effective methods for deodorization and has been widely used.…”