23
2
two steps. If necessary, bleaching with
bleaching earth or adsorption on activated
carbon can follow.
5 The last step is damping the oil. Volatile
products of the oil are removed according to
the well-known principle of vacuum steam
distillation. Since unpleasant odors are also
removed during this damping process, this is
referred to as deodorization of the oil.
If one examines the chemical composition of
the coconut oil thus obtained, the fatty acid distribution already presented in . Table 2.3 (line 1)
results: The triglycerides of coconut oil contain in
large proportions the “lauric”, i.e. the lauric acid
and the myristic acid, and in only small proportions the palmitic, stearic and oleic acids. Coconut oil is therefore an excellent raw material for
detergent alcohols (cf. 7 Chap. 3).
2.2.2 Palm Oil and Palm Kernel Oil
Another important type of palm is the oil palm
(Elaeis guineensis). It originates from the rainforests of Guinea and has therefore been given its
botanical name. Already in 1466, the Portuguese
5 This extraction can be carried out, for example, with n-hexane or with gasoline, whereby
the extraction material is fed in countercurrent to the solvent. The solvent is then
separated off again by distillation.
5 Modern processes use supercritical carbon dioxide (scCO 2 ) as extraction agent.
However, these processes require high
pressures and are therefore more expensive.
The advantage is that the carbon dioxide
evaporates completely when the solution is
released and thus no residual solvents are
contained in the oil.
The “crude oils” isolated in this way still have
to be processed in a further refinery:
5 During degumming, hydrolysis precipitates
proteins and phospholipids, making the oil
much more stable in storage.
5 Enzymatically or microbially the triglycerides
can split off free fatty acids which give the
oil unfavorable properties. These fatty acids
are neutralized in deacidification by adding
alkali solutions, e.g. diluted NaOH.
5 Oils may contain natural colorants, e.g.
carotenoids or chlorophyll. Most of these
substances are already removed in the first
Silo
Heating
Crude oil
Filter press
Extraction
Screw press
Oil
tank
Grinding
mill
Crusher
Oil
. Fig. 2.5 Mechanical processes for oil extraction from oil fruits
2.2 · Overview of Important Vegetable Oils and Animal Fats
2
two steps. If necessary, bleaching with
bleaching earth or adsorption on activated
carbon can follow.
5 The last step is damping the oil. Volatile
products of the oil are removed according to
the well-known principle of vacuum steam
distillation. Since unpleasant odors are also
removed during this damping process, this is
referred to as deodorization of the oil.
If one examines the chemical composition of
the coconut oil thus obtained, the fatty acid distribution already presented in . Table 2.3 (line 1)
results: The triglycerides of coconut oil contain in
large proportions the “lauric”, i.e. the lauric acid
and the myristic acid, and in only small proportions the palmitic, stearic and oleic acids. Coconut oil is therefore an excellent raw material for
detergent alcohols (cf. 7 Chap. 3).
2.2.2 Palm Oil and Palm Kernel Oil
Another important type of palm is the oil palm
(Elaeis guineensis). It originates from the rainforests of Guinea and has therefore been given its
botanical name. Already in 1466, the Portuguese
5 This extraction can be carried out, for example, with n-hexane or with gasoline, whereby
the extraction material is fed in countercurrent to the solvent. The solvent is then
separated off again by distillation.
5 Modern processes use supercritical carbon dioxide (scCO 2 ) as extraction agent.
However, these processes require high
pressures and are therefore more expensive.
The advantage is that the carbon dioxide
evaporates completely when the solution is
released and thus no residual solvents are
contained in the oil.
The “crude oils” isolated in this way still have
to be processed in a further refinery:
5 During degumming, hydrolysis precipitates
proteins and phospholipids, making the oil
much more stable in storage.
5 Enzymatically or microbially the triglycerides
can split off free fatty acids which give the
oil unfavorable properties. These fatty acids
are neutralized in deacidification by adding
alkali solutions, e.g. diluted NaOH.
5 Oils may contain natural colorants, e.g.
carotenoids or chlorophyll. Most of these
substances are already removed in the first
Silo
Heating
Crude oil
Filter press
Extraction
Screw press
Oil
tank
Grinding
mill
Crusher
Oil
. Fig. 2.5 Mechanical processes for oil extraction from oil fruits
2.2 · Overview of Important Vegetable Oils and Animal Fats