Science Record

ia Neen)

13

According to the experimental data in Tables 1, 2, 3 and 4, we may point out:

t(hr.)

Fig. 5 Reactions of equivalent quantity ratio of sebacic acid with iso-octyl alcohol at 160°C catalyzed by 6.4275 N sulfuric acid.

I. There are probably two best ways for obtaining the highest yield for preparation of normal octyl sebacate. First, the experimental No. 3'in Table 1 is an example to give more than 90 per cent of the product in the absence of foreign acid, if we raise the temperature and prolong the time of reaction; Secondly, the experimentals No. 1 and 2 are two examples of producing more than 95 per cent of the product in the presence of a very small quantity of sulfuric acid added as catalyst.

Il. For gaining more than 90 per cent of iso-octyl sebacate we have to add sulfuric acid as catalyst, raise the temperature and prolong the time of reaction, such as exp. No. 3 in Table 4.

CONCLUSIONS

We have studied the kinetics of esterification between sebacic acid with normal-octyl alcohol and that with iso-octyl alcohol at different temperatures in the presence or absence of sulfuric acid as catalyst. According to our experimental results, we have pointed out the best conditions for preparation of normal-octyl and iso-octyl sebacates. Furthermore, our experimental results confirm once more the mechanism of hydrogen ion catalysis in esterification as suggested by us.