Vol 7, No 1 (2016) > Chemical Engineering >

Wax Aggregation Inhibition in Crude Oil by Oxirane Ester Copolymer

Yoki Yulizar, Tresye Utari, Destia Puteri Ananda


Abstract: Wax deposition can cause a
serious problem in the distribution process of crude oil through a pipeline. At
low temperatures, wax molecules can interact to form a wax aggregate. One way
to reduce the wax aggregation is to introduce an additive compound into the
crude oil. In this
study, 15 crude oil models were prepared by mixing gasoline, kerosene, oil,
wax, and asphaltene. Oxirane ester copolymer (OEC) additive was introduced into
the crude oil models with various concentrations and volumes, and its effect on
the crude oil models’ pour point and viscosity were evaluated. OEC
interactions with wax and asphaltene were observed by FTIR, and the wax
aggregation process was observed using cross polarized microscopy (CPM). The
optimum pour point of crude oil was reached at a temperature of 6oC
and optimum viscosity at 10 cSt for the selected model 4. OEC additions of 5% and
10% require 500 and 300 µL, respectively, to achieve the optima pour point
and viscosity. OEC was able to inhibit the wax aggregation, as evidenced from
the interaction between OEC-wax at 722 cm-1 and OEC-asphaltene at 1604 and 1494 cm-1 of FTIR
spectra. The distribution of the wax aggregate was observed using CPM, with the
value of the wax appearance temperature (WAT) at 28.7oC. This research can be the basis for designing or
selecting a molecule for use as a pour point depressant in accordance with the
characteristics of crude oil, particularly since each source of crude
oil has different characteristics.
Keywords: Crude oil; Inhibition process; Oxirane ester copolymer; Pour point; Wax

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