Critical temperatures and pressures and high temperature vapour pressures of seven alcohols

Critical temperatures and pressures have been determined experimentally for the four lowest n-alcohols, 2-propanol, 2-butanol, and 2-methyl-1-propanol, and are given in the penultimate line of Table 3. The last line of Table 3 lists the weighted mean critical pressures, with the corresponding critical temperatures obtained from he vapour pressure equation. Comparison with the corresponding data from standard reference books reveals deviations from the experimental data in some [2, 4] and incorrect critical pressure for ethanol in all five reference books quoted in Table 3. In addition, vapour pressure data were obtained for the same alcohols in the temperature range approaching the critical point. The measurements are reproduced by the simplified Clausius-Clapeyron equation with the constants and standard deviation given in Table 2.     

Technologies providing for competitiveness of main refractories on the domestic and foreign markets

The paper considers technological innovations successfully used in large-scale production, which ensure good competitive prospects for the Magnezit Works with respect to its competitors. __________ Translated from Novye Ogneupory, No. 12, pp. 13–17, December, 2006.     

Simultaneous afterclearing and decolorisation by ozonation after disperse dyeing of polyester

A set of trials have been conducted to examine the efficiency of ozonation on afterclearing of disperse dyed poly(ethylene terephthalate) fibres. Ozonation was performed in the cooled dyebath after the completion of the dyeing cycle. The ozone concentration used was 12.8 ± 0.3 mg/min at a gas flow rate of 400 ml/min. The results indicate that 3 min ozonation time is appropriate to achieve wash fastness results comparable to conventional reduction clearing. These results were obtained with simultaneous dyebath decolorisation ratios up to 67% and without significant colour yield ( K/S value) losses of the dyed fabric. Ozonation periods exceeding 3 min caused significant colour yield ( K/S value) losses, although dyebath decolorisation ratios increased up to 82% and wash fastness properties further improved. The chemical oxygen demand of the dyeing process decreased up to 62% by the ozonation afterclearing. The advantages of the ozonation afterclearing process are savings in terms of water, energy and time and reduction in environmental load.     

Afterclearing by ozonation: a novel approach for disperse dyeing of polyester

A set of trials has been conducted to examine the efficiency of ozonation afterclearing on poly(ethylene terephthalate) fibres dyed with disperse dyes. The afterclearing process was performed in neutral distilled water at room temperature with 12.8 ± 0.3 mg/min ozone at 400 ml/min ozone gas flow rate. The results indicate that 1 min ozonation time is adequate to achieve wash fastness results comparable with conventional reduction clearing without significant colour yield losses. Ozonation periods greater than 1 min not only caused significant colour yield losses, but also caused a severe decrease of the breaking load of the fabric. The advantages of ozonation afterclearing are: savings in energy and time, as it is performed at room temperature for only 1 min, and decrease of environmental load as it avoids the use of the harsh chemicals used in conventional reduction clearing.