Abstract
Various kinds of waste paper with different ash content were solubilized by hot compressed water (HCW) in mini-batch reactor for the purpose of examining an optimum operating condition to yield a higher conversion rate of water-solubilized carbon. When the operating conditions of reaction temperature and time were varied, a maximum value of conversion rate of water-solubilized carbon reached around 50wt% and it was found formic, acetic and lactic acids were mainly produced. Waste paper with higher calcium carbonate content was favorable in producing much more amount of organic acids. As an example, the conversion rate of water-solubilized carbon of about 50wt% and acetic acid of 14700mg/L were obtained, when a flier, 26.3wt% ash content and 10wt% calcium carbonate content, was treated under the condition of 325°C and 120s. Ad-dition of hydrogen peroxide improved decomposition behavior of waste paper. In the case of using 5.2wt% hydrogen peroxide water solution as a hydrolysis medium, conversion rate of water-solubilized carbon reached about 43wt% and total organic acids of 13500mg/L was yielded in the treatment of the same flier despite of a milder condition of 275°C and 5min. Moreover, adherence of char to the inner wall of the reactor was markedly decreased.
