Systems and procedures carbonate matrix acidizing

The OMC structure also depends on the polymerization step. As mentioned above, the polymerization of the precursor adsorbed in the pore system of the matrix is catalyzed by acids. Different synthesis procedures were developed. For example, an acid solution can be added to the reaction mixture. In this case, the polymerization will take place throughout the entire pore system of the matrix. The resulting OMC can be described as a three-dimensional network of interconnected carbon rods. An example is CMK-3, already presented in Fig. 18.1. In this OMC, parallel-arranged carbon rods with a diameter of approximately 5 nm are connected by narrower carbon rods. The narrow carbon rods were formed in micropores that connect the mesopores of the SBA-15 silica matrix [21]. In an alternative synthesis procedure, a matrix with acid sites on the pore walls (e.g., an aluminosilicate) can be used. In this case, the polymerization of the precursor takes place on the mesopore walls and a carbon film is formed there, whereas the much narrower micropores are entirely filled with the polymerization product. Thus, after pyrolysis and removal of the matrix, the OMC consists of interconnected nanopipes, as opposed to interconnected carbon rods. An example is CMK-5. This OMC is synthesized in an acid form of the matrix used for the synthesis of CMK-3. Thus, CMK-5 consists of interconnected carbon nanopipes, arranged in the same fashion as the carbon rods of CMK-3 (Fig. 18.2) [22]. However, the pore system of these two OMCs differs. The pore system of CMK-3 consists of the voids in between the carbon rods, whereas in addition to these pores CMK-5 also has pores inside the nanopipes. 

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