@article{oai:kitami-it.repo.nii.ac.jp:00006180,
 author = {岡, 宏 and 佐々木, 満雄 and 大野, 豊},
 issue = {4},
 journal = {北見工業大学研究報告},
 month = {Mar},
 note = {application/pdf, In the process of extraction of humic acid from peat, the most difficult operations were filtration, washing and drying of free humic acid. So, in order to speed up the above operations, freezing treatment of free humic acid has been tried. This treatment of the precipitates of free humic acid (moisture content was about 700?900％ on dry bases) was carried out at ?10, -20 and ?30℃.　And frozen matter was melted at a room temp., and then the humic acid was separated by means of Buchner’s funnel from the liquor. The humic acid has been obtained in the form of about 16?30 meshes of even grains (moisture content was about 100?170％ on dry bases). In this case, operations as filtration, washing and drying of free humic acid were carried out very easy, and the necessary time was about one-tenth in comparison with the usual methods. The humic acid, obtained by the freezing method, was soluble in organic solvents more readily than that by the usual methods, and ion exchange type carboxyl group was decreased},
 pages = {71--76},
 title = {泥炭フミン酸に関する研究 （第５報 ）- 遊離フミソ酸の凍結処理 -},
 volume = {1},
 year = {1966}
}