Effects of Surface Features on Adsorption of SO₂ on Graphite Oxide/Zr(OH)₄ Composites

Abstract

Zirconium hydroxide/graphene composites were synthesized from zirconium chloride and graphite oxide with the content of the graphene component between 5 and 50%. They were used as adsorbents of sulfur dioxide at ambient conditions. The initial and exhausted materials were characterized using adsorption of nitrogen, infrared spectroscopy, potentiometric titration, scanning electron microscopy and thermal analysis. The results indicated enhanced adsorption of SO2 on the composites, which is linked to the formation of new basic sites and porosity as a result of interactions between zirconium hydroxide units and the oxygen groups attached to the graphene layers. Both physical adsorption and reactive adsorption of SO2 via formation of sulfites play a role in the retention process. The graphene component catalyzes oxidation of SO2 and leads to the formation of sulfates.

Reactive adsorption of hydrogen sulfide on graphite oxide/Zr(OH)4 composites

“…The details of synthesis of the particular GO used in this study are described elsewhere [29]. The preparation of the GO/zirconium hydroxide composites was described in details elsewhere [27]. Briefly GO was dispersed in zirconium chloride and then NaOH was added slowly in the stoichometric amount, which resulted in the precipitation of zirconium hydroxide.…”

“…The results indicated high adsorption capacity. The synergetic effect of the new composite porosity and chemistry was clearly seen [27].…”

“…As a surface reaction products sulfites were identified [26]. Following this path we investigated SO 2 adsorption on graphite oxides Zr(OH) 4 composites [27]. The results indicated high adsorption capacity.…”

Environmental applications using graphene composites: water remediation and gas adsorption

“…However, even with the inclusion of these reactive iron centers the The adsorption of SO 2 has been achieved using a hydrous zirconia-graphene composite, where the composite material adopts a Zr(OH) 4 bridged graphene layer structure. 200 The interactions between the zirconia and the graphene result in pores which increase the adsorption capacity of SO 2 under both dry and moist conditions compared to GO and pure Zr(OH) 4 , when the GO content is 5 wt%. When the GO content is increased there is an increased pore formation due to enhanced binding between GO and Zr(OH) 4 .…”

Key role of terminal hydroxyl groups and visible light in the reactive adsorption/catalytic conversion of mustard gas surrogate on zinc (hydr)oxides

“…The latter is owing to the high reactivity of their OH groups, especially terminal ones, with specific adsorbates. For example, Mabayoje and co-workers [11] found that the efficiency of SO 2 [12], NO 2 [13], and H 2 S [10] removal increased with an increase in the number of terminal hydroxyl groups detected on the surface. In addition, those OH groups can represent an important source of active radicals for photoactive reactions [10].…”