Co-Precipitated Cu/ZnO/Al₂O₃ Sorbent for Removal of Odorants t-Butylmercaptan (TBM) and Tetrahydrothiophene (THT) from Natural Gas

Abstract

The removal of sulfur-containing odorants from natural gas has been investigated by using sorption. The CuO/ZnO/Al2O3 sorbents were prepared by a coprecipitation/aging method. A reduced sorbent, namely, Cu/ZnO/Al2O3, has a sorption capacity of 0.5 mmol/g at 250 °C when the sodium content is kept below 0.027 wt %. The high sorption capacity of the sorbent is due to the better dispersion of nanocrystalline copper metal particles in a zinc oxide matrix as confirmed by X-ray diffraction analysis. The Brunauer−Emmett−Teller surface area of calcined material (Cu/ZnO/Al2O3) increased systematically from 18.38 to 104.26 m2/g with the lowering of the residual “Na” concentration. The temperature-programmed reduction study revealed that high incorporation of “Na” made the reduction of the CuO phase difficult in unwashed sorbent. However, as the “Na” content is lowered below 0.027 wt %, the reduction of CuO particles occurred at much lower temperatures because of the strong interaction of nanosized CuO with ZnO particles.

Effect of precipitants during the preparation of Cu-ZnO-Al2O3/Zr-ferrierite catalyst on the DME synthesis from syngas

“…The residues can be either deposited on Cu-ZnO-Al 2 O 3 component and/or ionexchanged with acidic sites on Zr-modified ferrierite. Enough care was taken in the present study, thorough filtering and washing steps, to bring down the metal residue content to below 0.01 wt.% [21]. Therefore, the metal ions are expected to occupy ionexchange positions (acidic surface) of ferrierite preferentially rather than their interaction with Cu-ZnO-Al 2 O 3 .…”

Reactive adsorption desulfurization of NiO and Ni0 over NiO/ZnO–Al2O3–SiO2 adsorbents: role of hydrogen pretreatment

“…A mixed aqueous solution of Al(NO 3 ) 3 and Zn(NO 3 ) 2 was dropwise added into a mixed solution of Na 2 CO 3 (0.2 mol L À1 ) and Na 2 -SiO 3 (0.2 mol L À1 ) at a rate of 15 mL min À1 at a precipitation temperature of 20 C, followed by aging at the same temperature for 2 h. Then, the precipitation was ltrated out and washed with a large quantity of deionized water to remove the residue sodium until the pH of the suspension is below 6.5. [25][26][27][28] Aer that, the lter cake was dried at 120 C in air for 12 h, and then calcinated at 500 C in a muffle furnace in dry air for 4 h. The supporter ZnO-Al 2 O 3 -SiO 2 was obtained.…”

Reactive Adsorption Desulfurization of Fluidized Catalytically Cracked (FCC) Gasoline over a Ca-Doped Ni-ZnO/Al2O3–SiO2 Adsorbent

“…The ZnO–Al 2 O 3 –SiO 2 adsorbent support was prepared by a coprecipitation method, and then Ni and Ca components were loaded on the supporter by impregnation method, shown in Figure . A mixed aqueous solution of Al­(NO 3 ) 3 and Zn­(NO 3 ) 2 was added dropwise into a mixed solution of Na 2 CO 3 (0.2 mol/L) and Na 2 SiO 3 (0.2 mol/L) at a rate of 15 mL/min at a precipitation temperature of 20 °C, followed by aging at the same temperature for 2 h. The precipitation then was filtered out and washed with a designated amount of deionized (DI) water to remove the residual sodium until the pH of the suspension was <6.5. − The filter cake was dried at 120 °C in air for 12 h and then calcinated at different temperatures in a muffle furnace in dry air for 4 h. In this way, the ZnO–Al 2 O 3 –SiO 2 support was obtained.…”