*3.1. Adsorbents Properties*

Five capping adsorbents, sieved to 30–60 mesh, were analyzed and their physical and chemical properties are summarized in Table 1, including the BET surface areas (SBET), average pore sizes, and total pore volumes (Vtotal). The data revealed that HAP had the absolutely largest BET surface area and pore volume among these five materials, and CB had a relatively larger specific surface area and the second largest pore volume.

**Table 1.** BET surface areas, average pore sizes and total pore volumes (Vtotal) of five materials.


The results of element analyses of the five materials are given in Table 2. FeS was not analyzed and theoretically it is composed of 63.64 wt% of iron and 36.36 wt% of sulfur. It can be seen that CB was rich in C (77.87 wt%) and had a great amount of S (2.53 wt%) because it originated from waste tire. OSP and HAP were rich in O (32.29 and 13.24 wt%, respectively). The proportions of C in OSP roughly corresponded to the proportion of CaCO3 in oyster shell.


**Table 2.** Elemental analyses of the five test materials.
