However, upon cooling, [QPS]PW and [PyPS]PW were precipitated
from the reaction mixture and their solubilities were gradually decreased due to their relatively low solubilities in methanol (Table 2,
entries 3 and 4). The precipitates were separated from the reaction
mixture by centrifugation, dried and weighed. The recyclabilities of
the catalysts based on wt.% of precipitate were reported in Table 2.
As can be seen, [QPS]PW showed desired temperature-dependence
solubility (Table 2, entry 4). This catalyst was soluble in the reaction
mixture at 65 °C (as a homogeneous catalyst) and precipitated quantitatively at the end of the reaction upon cooling. Therefore, it can be
separated easily as a heterogeneous catalyst. This catalyst was used
as the best one in further investigations.
The effects of catalyst loading and methanol to oil weight ratio were
investigated in the esterification of oleic acid with methanol using [QPS]PW as the best catalyst (Table 3).
However, upon cooling, [QPS]PW and [PyPS]PW were precipitated
from the reaction mixture and their solubilities were gradually decreased due to their relatively low solubilities in methanol (Table 2,
entries 3 and 4). The precipitates were separated from the reaction
mixture by centrifugation, dried and weighed. The recyclabilities of
the catalysts based on wt.% of precipitate were reported in Table 2.
As can be seen, [QPS]PW showed desired temperature-dependence
solubility (Table 2, entry 4). This catalyst was soluble in the reaction
mixture at 65 °C (as a homogeneous catalyst) and precipitated quantitatively at the end of the reaction upon cooling. Therefore, it can be
separated easily as a heterogeneous catalyst. This catalyst was used
as the best one in further investigations.
The effects of catalyst loading and methanol to oil weight ratio were
investigated in the esterification of oleic acid with methanol using [QPS]PW as the best catalyst (Table 3).
การแปล กรุณารอสักครู่..