Preparation of nodular carbon cryogel from simple and inexpensive polycondensation reaction of commercial modified black wattle tannin
Tannin–formaldehyde cryogels (TFC) were synthesized by sol–gel polycondensation of low molecular weight and highly reactive modified tannin with formaldehyde using HCl as a catalyst. Carbon cryogels (CC) were obtained by the TFC pyrolysis at an inert atmosphere at 800 °C. Pyrolysis caused significant changes in the physical and chemical properties of the material. The pyrolysis induced the decomposition of acid superficial groups and the development of basic ones. Pyrolysis also provoked significant change in the pore volume, forming a great amount of micropores. TFC and CC showed amorphous and turbostratic structures, respectively. Unpurified samples had inorganic impurities in their compositions.
KeywordsTannin Porosity Pyrolysis Carbon cryogel Adsorption
The authors gratefully acknowledge CAPES for financial support.
- 23.Kamachi M, Cheng XS, Kida T, Kajiwara A, Shibasaka M, Nagata S (1987) Synthesis of new polymers containing porphyrins in their side chains: radical polymerizations of 5-[4-(acryloyloxy)phenyl]-10,15,20-triphenylporphyrin and 5-[4-(methacryloyloxy)phenyl]-10,15,20-triphenylporphyrin. Macromolecules 20:2665–2669CrossRefGoogle Scholar