H2S adsorption onto Cu-Zn-Ni nanoparticles loaded activated carbon and Ni-Co nanoparticles loaded γ-Al2O3: Optimization and adsorption isotherms.

The nanocomposites based on copper, zinc and nickel were loaded on activated carbon (Cu-Zn-Ni-NPs-AC) and cobalt and nickel nanoparticles was loaded on γ-alumina (Ni-Co-NPs-γAl2O3) and applied for removal of hydrogen sulfide (H2S) from natural gas and their efficiency were compared. Cu-Zn-Ni/AC and Ni-Co/γ-Al2O3 was characterized using different techniques such as energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM). The effects of variables such as amount of adsorbent, flow rate, temperature, pressure and volume of gas on H2S removal were examined and optimum values were found to be 0.3g adsorbent, and flow rate of 0.15L/min and 15°C and 7Psi for both adsorbent and also 5.5 and 6.5L of sample by Cu-Zn-Ni/C and Co-Ni/γ-Al2O3, respectively. Setting conditions at the above optimum conditions lead to achievement of maximum removal of H2S (94% and 91.6%) by Cu-Zn-Ni/AC and Co-Ni/γ-Al2O3. The negative value of ΔG° and its numerical value confirm physisorption nature of adsorption. The experimental equilibrium data with high efficiency were explained and represented by Langmuir model for both adsorbents with the highest correlation coefficients.