Co-Pyrolysis of Beet Pulp and Defecation Lime in TG-MS System

The process of pyrolysis of beet pulp, a by-product after the extraction of raw sugar from sugar beet, with the addition of defecation lime was studied in a thermobalance coupled with a mass spectrometer. The beet pulp pyrolysis process took place completely at 600 °C, and the resulting char, tar and gas were characterized by higher heating values of 23.9, 21.6 and 7.77 MJ/kg, respectively. The addition of the defecation lime to beet pulp caused both an increase in the char production yield and a decrease in the tar production yield. At the same time, the higher heating value of char and tar decreased along with the increase of defecation lime added to the sample. The deconvolution of derivative thermogravimetric (DTG) curves allowed us to identify the basic components of beet pulp, for which the activation energy by isoconversion method was calculated. The 20 wt.% addition of defecation lime caused an increase of the activation energy by about 18%. Further increase in the defecation lime content resulted in a reduction of activation energy. At the temperature above 600 °C, calcination of calcium carbonate contained in defecation lime occurred. The CO2 produced during calcination process did not cause auto-gasification of char.

Kinetics of Interaction between Fullerol C60(OH)24 and Polyacrylic Hydrogels

In this paper kinetics of binding of fullerol to polyacrylic hydrogel at different temperatures, 298, 308 and 318 K, has been investigated. Time dependences of specific capacity of fullerol binding to hydrogel at defined temperatures are determined. Kinetic curves of specific binding capacity of fullerol for hydrogel are described by equations: t x k t x k x max 1 2 max 1 1+ = and x=k2tn. Rate constants k1 and k2 of the specific fullerol binding capacity at various temperatures are determined. Based on changes in constants k1 and k2 with temperature, kinetic parameters of the investigated process are calculated. Also, due to a great difference in values of kinetic parameters k1 and k2 obtained by varying the temperature, kinetic parameters are determined by using Friedman’s isoconversion method. The values of kinetic parameters based on temperature changes in k2 correspond to the values of kinetic parameters for 9 . 0 » a , while the values of kinetic parameters calculated according to the temperature change in k1, correspond to the Ea values. According to the obtained results it is concluded that the investigated process is controlled by diffusion.