Seite - 209 - in Advanced Chemical Kinetics

system.However, there isa significant increase in theconversionvalue from52%(200rpm) to 82%(520 rpm),which shows that for reactions like those,with lowcatalyst concentration, the rotationdoesnot interfere in the reactionvelocity,butat themaximumconversionvalue. Andwhat happens increasing 7.5 times the concentration of the catalyst? Does this pattern hold?Table4andFigure12 showtheanswers. Increasing the concentration of KOH clearly increases the rate of TAG consumption and, consequently, formation of FAME.While the reaction with 200 rpm reaches the maximum conversionand theequilibriumwith10minof reaction, the reactionat 520 rpmonly requires half the time,5min.However,despite thedecrease in time,weobservedthat thevalues for the maximumconversionareveryclose. Figure 11. Variation of (a) TAG concentration, (b) propagation velocity and (c) TAG conversion for the reactionswith 0.2%(w/w)ofKOH. 1.5%and200rpm 1.5%and520rpm Time[min] XTAG [%] CTAG [molL 1] υ [ms 1] XTAG [%] CTAG [molL 1] υ [ms 1] 0 0 0.83 1424.3 0 0.83 1421.3 1 8.3 0.75 1368.7 52.8 0.65 1363.2 5 71.5 0.24 1358.0 85.9 0.12 1358.8 10 81.6 0.15 1356.1 87.7 0.10 1357.6 20 82.5 0.15 1355.4 88.7 0.09 1356.3 40 83.4 0.14 1353.9 89.1 0.09 1356.9 Table 4. Results for 1.5% (w/w) ofKOHreactions. Ultrasound as a Metrological Tool for Monitoring Transesterification Kinetics http://dx.doi.org/10.5772/intechopen.70501 209