7 Technologies for Conversion Bio-Lubricant …
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additives [5]. These elements protect the metal surface with easily sheared layers of
chlorines, phosphides, or sulfides, which forbid severe seizure and wear. However,
it should be noted that the use of these elements is controlled due to environmental
concerns—since these elements lead to corrosion of metal specimens as well as pollution [22]. In the past ten years, nitrogen-containing heterocyclic compounds and their
derivatives have become research hotspots for green lubricating oil additives. The
reported multifunctional lubricating oil additives containing nitrogen heterocyclic
derivatives can be summarized as thiadiazole, thiazole, benzothiazole, benzotriazole, morpholine, imidazoline, and triazine [40, 42]. Kalam investigated that waste
vegetable oil-contaminated lubricants with amine phosphate as anti-wear additive
reduced wear and friction coefficient as the same time increased viscosity [18, 25].
Other Additives
Plant oils and synthetic esters are easily hydrolyzed to produce acidic substances
that can cause metal rust. To achieve a good rust-proof effect, rust inhibitors need
to be added. The main types of lubricating oil rust inhibitors are sulfonates, carboxylic acids/carboxylates, alcohols, esters, organic amines, phosphoric acid, and
phosphates.
Thickeners that are commonly known for increasing viscosity can be used for
biodegradable greases. Although inorganic thickeners such as clay and silica cannot
be biodegraded in the environment, they do not pose a hazard to the environment
therefore still be used. Because soap-based greases such as lithium/calcium-based
mixed soaps, C 18 H 35 O 3 Li or (C 18 H 35 O 3 ) 2 Ca, and composite aluminum soaps have
good heat resistance and water resistance, they can also be used as thickeners. Of
course, the choice of thickener can also be determined by the properties such as
viscosity, toxicity, and degradability of the grease.
Other lubricant additives include corrosion inhibitors such as fatty acid derivatives, amines, imidazolines, and triazoles for preventing corrosion of equipment;
anti-foaming agent such as polysiloxanes and methacrylates to prevent foaming;
biodegradation accelerators such as phosphor-nitrogen modified fatty acid [7], etc.
7.2.3.2 Bio-Lubricant Blending Technology
Bio-Lubricant Blending Process
Lubricant blending is mostly a homogenous phase mixing process. When the lubricant additive is a solid, it is a heterogeneous phase mixing process, during which
solid additives will eventually dissolve and form a homogeneous phase. It is generally believed that the liquid-liquid homogenous mixing is a combination of three
diffusion mechanisms: molecular diffusion, eddy diffusion, and convection diffusion.
The blending of lubricant has two methods: intermittent and continuous blending.
During intermittent blending process, the material is blended under the effect of
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additives [5]. These elements protect the metal surface with easily sheared layers of
chlorines, phosphides, or sulfides, which forbid severe seizure and wear. However,
it should be noted that the use of these elements is controlled due to environmental
concerns—since these elements lead to corrosion of metal specimens as well as pollution [22]. In the past ten years, nitrogen-containing heterocyclic compounds and their
derivatives have become research hotspots for green lubricating oil additives. The
reported multifunctional lubricating oil additives containing nitrogen heterocyclic
derivatives can be summarized as thiadiazole, thiazole, benzothiazole, benzotriazole, morpholine, imidazoline, and triazine [40, 42]. Kalam investigated that waste
vegetable oil-contaminated lubricants with amine phosphate as anti-wear additive
reduced wear and friction coefficient as the same time increased viscosity [18, 25].
Other Additives
Plant oils and synthetic esters are easily hydrolyzed to produce acidic substances
that can cause metal rust. To achieve a good rust-proof effect, rust inhibitors need
to be added. The main types of lubricating oil rust inhibitors are sulfonates, carboxylic acids/carboxylates, alcohols, esters, organic amines, phosphoric acid, and
phosphates.
Thickeners that are commonly known for increasing viscosity can be used for
biodegradable greases. Although inorganic thickeners such as clay and silica cannot
be biodegraded in the environment, they do not pose a hazard to the environment
therefore still be used. Because soap-based greases such as lithium/calcium-based
mixed soaps, C 18 H 35 O 3 Li or (C 18 H 35 O 3 ) 2 Ca, and composite aluminum soaps have
good heat resistance and water resistance, they can also be used as thickeners. Of
course, the choice of thickener can also be determined by the properties such as
viscosity, toxicity, and degradability of the grease.
Other lubricant additives include corrosion inhibitors such as fatty acid derivatives, amines, imidazolines, and triazoles for preventing corrosion of equipment;
anti-foaming agent such as polysiloxanes and methacrylates to prevent foaming;
biodegradation accelerators such as phosphor-nitrogen modified fatty acid [7], etc.
7.2.3.2 Bio-Lubricant Blending Technology
Bio-Lubricant Blending Process
Lubricant blending is mostly a homogenous phase mixing process. When the lubricant additive is a solid, it is a heterogeneous phase mixing process, during which
solid additives will eventually dissolve and form a homogeneous phase. It is generally believed that the liquid-liquid homogenous mixing is a combination of three
diffusion mechanisms: molecular diffusion, eddy diffusion, and convection diffusion.
The blending of lubricant has two methods: intermittent and continuous blending.
During intermittent blending process, the material is blended under the effect of