Methanation gravimetric measurements

Buss, E., Gravimetric measurement of binary gas adsorption equilibria of methane-carbon dioxide mixtures on activated carbon. Gas Sep. Purif, 9(3), 189-198 (1995). 

Densimetric-gravimetric measurements of binary coadsorption equilibria have been performed at IFT using the instrument shown in Figs. 4.13, 4.14 in 2001-2002, [4.17]. The system chosen was carbon dioxide (CO2), methane (CH4), and activated carbon (AC) D 47/3 at T = 293 K for pressures up to... 

Combined dielectric gravimetric measurements of adsorption equilibria Nitrogen (Na, 5.0), methane (CH4, 5.5) and carbon monoxide (CO, 3.7) on pellets AC-20 (Engelhard Process Chemicals, Nienburg) (Fig. 6.28). 

Figure 6.31. Specific volume of polycarbonate (GoodfeUow, UK) swelling due to the sorption of methane (CH4, 5.5) at T = 308 K for pressures up to 4 MPa and static dielectric permittivity (8,) of the (methane loaded) polymer [52, 6.3]. The volume has been determined by combined osciUometiic-gravimetric measurements, cp. Chap. 5. Figures 6.30, 6.31 refer to the same set of combined oscillometric-gravimetric-dielectric experiments [6.3, 6.41].

Isotherm measurements of methane at 298 K can be made either by a gravimetric method using a high pressure microbalance [31], or by using a volumetric method [32]. Both of these methods require correction for the nonideality of methane, but both methods result in the same isotherm for any specific adsorbent [20]. The volumetric method can also be used for measurement of total storage. Here it is not necessary to differentiate between the adsorbed phase and that remaining in the gas phase in void space and macropore volume, but simply to evaluate the total amount of methane in the adsorbent filled vessel. To obtain the maximum storage capacity for the adsorbent, it would be necessary to optimally pack the vessel. 

Total carbon in beryllium is determined by combustion of the sample, along with an accelerator mixture of tin, iron, and copper, in a stream of oxygen (15,16). The evolved carbon dioxide is usually measured by infrared absorption spectrometry. Beryllium carbide can be determined without interference from graphitic carbon by dissolution of the sample in a strong base. Beryllium carbide is converted to methane, which can be determined directly by gas chromatography. Alternatively, the evolved methane can be oxidized to carbon dioxide, which is determined gravimetrically (16). 

Gravimetric (Adsorption and Desorption) Measurements of Surface Species Formed during Methanation on Fresh and Sulfur-Poisoned 14/ Ni/Al203 at 675 K°... 

Henry constants and saturation concentrations obtained from the gravimetric sorption measurements on silicalite particles and diffusion constants obtained by the membrane method of methane and n-butane. After Vroon et al. [72-74]... 

In this work, the mechanism of methane oxidation over PCI/AI2O3 catalyst is investigated, the palladium oxidation state under stream reaction is identified and the reactive form of oxygen is determined. XPS, thermal gravimetric and surface potential measurements are performed on this catalyst under various dynamic gaseous treatments. 

Combined dielectric gravimetric oscillometric measurements of sorption equilibria of methane (CH4, 5.5) in polycarbonate (Goodfellow, UK), cp. Chap. 5, Sect. 3.4, (Figs. 6.30, 6.31). 

Ad 4. Dielectric-gravimetric-oscillometric measurements of sorption equilibria of methane in (swelling) polycarbonate. 

---