Adsorption of hydrogen sulfide by biochars derived from pyrolysis of different agricultural/forestry wastes

Abstract

This paper focuses on the adsorption of hydrogen sulfide (H₂S) by biochars derived from wastes. The characteristics and mechanisms of hydrogen sulfide (H₂S) adsorption on three different boichars derived from agricultural/forestry wastes through pyrolysis at various temperatures were investigated. In this study, the H₂S breakthrough capacity was measured using laboratory characterization with pH and Fourier-transform infrared spectroscopy analysis. The results obtained demonstrate that all biochars were effective in H₂S sorption. The sorption capacity of the biochar for H₂S removal is related to the pyrolysis temperature and pH of the surface.

Physical Activation of Waste-Derived Materials for Biogas Cleaning

“…As reported by Nabais et al (2007), physical activation with CO 2 promotes pore size and surface area increasing, with better performance than steam activation [55]. Activated biochar shows an adsorption capacity comparable to commercial sorbents, as reported also from [37,61]. Increasing the saturation zone of the filter, from 1% to 10% up to 100%, the adsorption capacity increases up to the saturation of pores, see Table 3.…”

“…In this work two waste-derived materials have been selected, such as char from the pyrolysis of wood waste, and ashes from the combustion of wood chips in a boiler. Virgin chars, as reported also in this article have lower adsorption capacity for the removal of trace compounds, especially sulphur compounds [37]. The activation methods are divided into chemical and physical origin.…”

“…Metal oxides are able to promote the dissociation of H 2 S and the HS − reaction to form sulphides. These reaction are reported in literature studies, as studied from Shang et al (2016) [37]. This was due to the chemical mechanisms developed between trace compounds to be removed and metals [62].…”

“…Thermo-chemical processes are applied to biomass, as reported in literature using pyrolysis or gasification systems [36]. Pyrolysis process produces char and oil, with a high potential for recovering energy [37,38]. Another waste material suitable for the gas cleaning of biogas is wood ash [39].…”

Mitigation of Gaseous Emissions from Swine Manure with the Surficial Application of Biochars

“…Results from an experiment conducted by Komnitnas et al, 2016 [28], show that biochar can adsorb 77% of phenol and 26% of NH3 emitted according to Li et al [29]. A mini-review of research on uses of biochar as an adsorbent for different gases in laboratory-scale experiments is summarized in Table 3 [28][29][30][31].…”