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4.1.2 Process I ntroduction while the moisture and the azeotropic agent Cyclohexane will
removed from the top. Subsequently it's fed into the rectify
IPA and water will form an azeotrope, which cannot be
column with metal filter on the top and particle filters to make
separated into pure substances by traditional distillation. The
electronic grade 5N IPA product with impurities at or less
most commonly used method in industry to separate IPA/
than ppt level. See more details in Figure 7 below.
water azeotrope is to add an entrainer to form a low-boiling
three-component azeotrope. The Table 3 below shows the 4.1.3 Plant Layout
boiling point and the azeotrope of the cyclohexane/IPA/
As shown in Figure 8 below, the waste IPA will be
water system. Among them, the three-component azeotrope
shipped by tank trucks from F15A or F15B, and transferred it
has the lowest boiling point, and the water is removed by
to IPA waste tank area. Then waste IPA is pumped to Process
the formation of the three-component azeotrope at the top
area for purification. The final IPA product will be uploaded
of the tower, and the IPA product can be obtained at the
to tank truck in product filling area and sent back to F15A or
bottom of the tower.
F15B for use.
Some wastewater containing IPA and impurities will be
Table 3、The Azeotrope of the Cyclohexane/IPA/Water system
treated in wastewater treatment area before discharging back
共沸物 共沸點(℃) 共沸組成(wt%) to CTSP WWTP(wastewater treatment plant).
環已烷 IPA H 2 O
環已烷-IPA 69 68.8 31.2
環已烷-H 2 O 69.2 91.6 8.36 4.1.4 Project Milestone
IPA-H 2 O 80.2 87.1 12.9
環已烷-IPA-H 2 O 63.4 71.9 21.8 6.26
As shown in Figure 9, the supplier will take about 4
months to apply CTSP member in order to rent the land and
Waste IPA, about 10-20% od IPA, is fed into the primary
apply construction permits. The construction will start around
distillation column, where the product will be concentrated
11/E in 2021 and take about 14 months to complete including
to 85% of IPA from top of the column and the majority of
equipment installation. The commissioning will start from
moisture and metal will removed from the bottom. Then it's
February 2023 but the operation permits may take about 6
fed into azeotropic distillation column, where the product will
months. Thus the normal operation is debuted on 7/E in 2023.
be concentrated to>99% of IPA from bottom of the column

Figure 7、Process Flow Diagram of IPA Purification

FACILITY JOURNAL 09 2021 63