Mercury porosimetry report

An examination of the data shows that 6% of the mercury intruded into pores smaller than 0.007 pm but that these micropores contributed 59% of the surface. 18% of the mercury intruded into pores in the size 

Pressure (P) psia Intnided volume V) cm3 g-1 Pore radius r) p.m Cumulative surface (S) m g-l Mean radius (0 um dV dS 

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The poly-[HIPE] sample intrusion mercury porosimetry study reported in Figure 4.67 was carried out in a Micromeritics, Atlanta, GA, USA, AutoPore IV-9500 automatic mercury porosimeter.1 The sample holder chamber was evacuated up to 5 x 10-5 Torr the contact angle and surface tension of mercury applied by the AutoPore software in the Washburn equation to obtain the pore size distribution was 130° and 485mN/m, respectively. Besides, the equilibration time was 10 s, and the mercury intrusion pressure range was from 0.0037 to 414 MPa, that is, the pores size range was from 335.7 to 0.003 pm. The poly-(HIPE) sample was prepared by polymerizing styrene (90%) and divinylbenzene (10%) [157],... 

Table 1 summarizes the results. For Vycor, an average pore size 44 A is calculated, which is in an excellent agreement with that claimed by the manufacturer and also reported to several other studies [14, 20]. For CPG s the calculated pore sizes are in good agreement with their nominal ones. One may note that the polydispersity in CPG s is slightly overestimated. Further detailed analysis of the results and comparison with gas adsorption and mercury porosimetry data is under progress. 

The surface area of MCM-41 obtained by mercury porosimetry, calculated using the Rootare-Prenzlow equation, " is lower than that found by the adsorption method, as shown in Table 2. In general for MCM-41, the surface areas obtained were in the following order mercury porosimetry < gas adsorption < SAXS < SANS. The mesopore diameters of the MCM-41 studied in the current work are in the range of 2.3 - 4.4 nm, and the lowest diameter of the cylindrical pores in which mercury can penetrate (at the highest pressure studied in this work) is about 3.2 nm. Therefore, if the walls of the pores are rigid, for the samples C14-C18 the surface area reported by mercury porosimetry is too low. 

Several determination methods of a porous texture can be used for characterizing the supports. Certain of these methods (i.e., scanning electron microscopy, mercury porosimetry) are described in other chapters of this book. We shall only report here the specific methods of support characterization. 

Chemical characterization total metal analysis has been performed using atomic adsorption spectroscopy (Varian Techtron analyzer). Metals were reported in % by weight (bulk) of total metal oxides in the support (W, Ni, Pt / Al-Si support). See Table 1. Physical method Surface, pore volume, and average pore diameter were measured using standard nitrogen adsorption and mercury porosimetry methods. See Table 1. 

GMA-EGDM copolymer beads were synthesised as reported earlier [16]. The surface area and pore volume were determined by mercury porosimetry. 2-Picolyl amine copolymers were generated by reacting 17 mmole of 2-picolyl amine with 5g (8.5 mmole) of GMA-EGDM copolymer in ethanol at 70°C for 24 hours. 

The basical theories, equipments, measurement practices, analysis procedures and many results obtained by gas adsorption have been reviewed in different publications. For macropores, mercury porosimetry has been frequently applied. Identification of intrinsic pores, the interlayer space between hexagonal carbon layers in the case of carbon materials, can be carried out by X-ray dififaction (XRD). Recently, direct observation of extrinsic pores on the surface of carbon materials has been reported using microscopy techniques coupled with image processing techniques, namely scarming tunneling microscopy (STM) and atomic force microscopy (AFM) and transmission electron microscopy (TEM) for micropores and mesopores, and scanning electron microscopy (SEM) and optical microscopy for macropores [1-3],... 

Equation (6.13) requires only the measurement of the dependence of the volume of the intruded mercury on the applied pressure, and can be used to investigate irregularities of the solids within the range of scales provided by mercury intrusion data. Application of the mercury porosimetry technique has been reported in several papers studying soils [14, 17, 33, 37 5]. 

There is a scarcity of studies in the literature for pore size distributions in the range where mercury porosimetry and the BET Kelvin method overlap. However, the pore size distribution of CPG 75 in the 10 nm range as measured using porosimetry was in excellent agreement with that measured using BET surface area, as reported by Porcheron et al. [52] (see Figure 3.12b). 

The porous network characteristics (specific pore volume, mean pore size, pore size distribution, etc.) reported in the literature are usually obtained either by adsorption of nitrogen [111] or by non-intrusive mercury porosimetry [112] and are discussed in detail in Chap. 21. An example of pore size distribution obtained by non-intrusive mercury porosimetry is presented in Figure 2.13. 

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