8 Oleochemistry Products
207
8.2.1 Introduction and Reason to Favour Oleochemicals
Surfactants
Surfactants are amphiphilic compounds containing both hydrophobic and
hydrophilic moieties, thus conferring them the ability to accumulate at the interface between fluid phases, such as oil/water or air/water, reducing the surface and
interfacial tensions to form emulsions. They do their function through their structure,
as it contains a hydrophilic head and hydrophobic tail, that enables them to interpose
themselves between water and water-insoluble substances. Surfactants are classified
according to their ionic properties in water as anionic, cationic, non-ionic or amphoteric surfactants depending on the type and charge of the hydrophilic groups. Surfactants are used in very wide applications such as household detergents, cleansing
sector, textile treatment, food, industrial cleanser, cosmetics, personal care products,
crop protection in mining and also has its applications in the production of paints,
dyes and paper [85, 185, 222].
Traditionally, surfactants are produced by organic chemical reactions from
petroleum feedstock on one hand. On the other hand, the growing awareness towards
the use of renewable-based products and ‘green products’ has stimulated the development of alternatives to these chemical surfactants [222]. Environmental protection
has led to the phasing out of surfactants having toxicological effects on nature (synthetic surfactants). In addition, biodegradability has become an important factor in
the environmental acceptance of a surfactant. Synthetic surfactants, i.e. alkyl phenols,
have often shown good functional properties but it has its hazard on the environment.
This has led to the development of surfactants based on natural products using millions of components that can be used as raw material. Many natural raw materials
incorporate special structures in the surfactant that may reveal new and unexpected
functional properties, which can lead to good substitutes for the traditional surfactants. Fatty acids, monoglycerides and glucosides are natural raw materials that have
been used for many years in the production of surfactants. Sterols are a more novel
class of surfactant raw materials from a natural origin [69].
The toxicological and environmental properties of surfactants based on oleochemicals are not necessarily better than those of surfactants prepared from petrochemical
products. However, the life cycle of a surfactant also needs to be studied. For example, the transport cost is an important factor, and it is thus of interest to source raw
materials that are locally available. Other life cycle aspects are, for example, the
biodegradability and toxicity of the surfactants; how long it takes for a sewage treatment plant to degrade the surfactant; and the eco-toxicity of the degradation products.
Furthermore, the synthesis of the surfactant plays a role: how many steps are needed,
how much carbon dioxide is produced and how toxic are the by-products. Sterol
surfactants have been used as a surfactant for years and it has two sources, synthetic
ethoxylated sterols and natural steryl glucosides [69].
Surfactants from renewable resources contribute less to the greenhouse effect if
harvested and grown sustainably. When the life cycle of the product is analysed
covering the CO 2 emissions from production, use and degradation after disposal,
207
8.2.1 Introduction and Reason to Favour Oleochemicals
Surfactants
Surfactants are amphiphilic compounds containing both hydrophobic and
hydrophilic moieties, thus conferring them the ability to accumulate at the interface between fluid phases, such as oil/water or air/water, reducing the surface and
interfacial tensions to form emulsions. They do their function through their structure,
as it contains a hydrophilic head and hydrophobic tail, that enables them to interpose
themselves between water and water-insoluble substances. Surfactants are classified
according to their ionic properties in water as anionic, cationic, non-ionic or amphoteric surfactants depending on the type and charge of the hydrophilic groups. Surfactants are used in very wide applications such as household detergents, cleansing
sector, textile treatment, food, industrial cleanser, cosmetics, personal care products,
crop protection in mining and also has its applications in the production of paints,
dyes and paper [85, 185, 222].
Traditionally, surfactants are produced by organic chemical reactions from
petroleum feedstock on one hand. On the other hand, the growing awareness towards
the use of renewable-based products and ‘green products’ has stimulated the development of alternatives to these chemical surfactants [222]. Environmental protection
has led to the phasing out of surfactants having toxicological effects on nature (synthetic surfactants). In addition, biodegradability has become an important factor in
the environmental acceptance of a surfactant. Synthetic surfactants, i.e. alkyl phenols,
have often shown good functional properties but it has its hazard on the environment.
This has led to the development of surfactants based on natural products using millions of components that can be used as raw material. Many natural raw materials
incorporate special structures in the surfactant that may reveal new and unexpected
functional properties, which can lead to good substitutes for the traditional surfactants. Fatty acids, monoglycerides and glucosides are natural raw materials that have
been used for many years in the production of surfactants. Sterols are a more novel
class of surfactant raw materials from a natural origin [69].
The toxicological and environmental properties of surfactants based on oleochemicals are not necessarily better than those of surfactants prepared from petrochemical
products. However, the life cycle of a surfactant also needs to be studied. For example, the transport cost is an important factor, and it is thus of interest to source raw
materials that are locally available. Other life cycle aspects are, for example, the
biodegradability and toxicity of the surfactants; how long it takes for a sewage treatment plant to degrade the surfactant; and the eco-toxicity of the degradation products.
Furthermore, the synthesis of the surfactant plays a role: how many steps are needed,
how much carbon dioxide is produced and how toxic are the by-products. Sterol
surfactants have been used as a surfactant for years and it has two sources, synthetic
ethoxylated sterols and natural steryl glucosides [69].
Surfactants from renewable resources contribute less to the greenhouse effect if
harvested and grown sustainably. When the life cycle of the product is analysed
covering the CO 2 emissions from production, use and degradation after disposal,