Colour and chlorophyll removal
Oils such as rapeseed and soybean carry chlorophyll, and palm oil carries carotenoids. Insufficient adsorption leaves colour that later processing may not remove, and the oil can miss customer specifications.
Industry · Edible Oil Refining
Bleaching Earth for Edible Oil Refining
Acid-activated bleaching clays that remove colour, trace metals and soaps from vegetable oils and fats, with grades for standard, demanding and speciality oils.
ISO 9001 certified processes
NABL-accredited lab testing
CoA, TDS & MSDS with every shipment
Export packaging worldwide
Overview
Minerals engineered for edible oil refining
Bleaching earth for edible oil refining is an acid-activated clay that adsorbs pigments, trace metals, soaps and oxidation products from crude and degummed oils. Obsidian Minerals supplies bleaching earth grades to refiners of palm, soybean, sunflower, rapeseed, rice bran and other vegetable oils, as well as fats and mineral oils.
In the bleaching step, the clay is dosed into hot oil under vacuum, held for a set contact time and removed by filtration. Its performance rests on the surface area, pore structure and acidity created during activation. A more active clay removes chlorophyll, carotenoids and phosphorus at a lower dosage, which reduces spent-earth volume and the oil retained in the filter cake. Free acidity and filtration rate matter too: excess acidity can raise free fatty acids, and slow-filtering earth limits throughput. Attapulgite, with its fibrous structure, is used in some blends to support adsorption and filtration.
Our edible oil range comprises standard bleaching earth, a high activity grade and a low free acid grade for speciality oils. Lots are tested in our NABL-accredited laboratory and shipped with a TDS and batch CoA. Customers should confirm suitability for food-contact processing in their market. Samples are available for laboratory bleaching tests on your own oil.
Problems we help solve
Oil retention and refining loss
Spent bleaching earth retains oil in the filter cake. Higher clay dosage means more oil lost and more waste to handle, so activity per kilogram directly affects refining economics.
Trace metals, soaps and phosphorus
Residual iron, copper, soaps and phospholipids shorten shelf life and poison hydrogenation catalysts. Bleaching must reduce them to low levels before deodorisation or further processing.
Filtration rate
Slow-filtering clay limits plant throughput and blinds filter leaves. Refiners need a consistent particle size distribution so filters build a permeable cake and cycle times remain predictable.
Recommended products for Edible Oil Refining
Bleaching Earth
Standard Bleaching Earth
Acid-activated bleaching earth for routine refining of palm, soybean and sunflower oils, removing colour pigments, soaps and trace metals at a practical dosage with good filtration behaviour.
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Bleaching Earth
High Activity Bleaching Earth
High activity bleaching earth for difficult crude oils and mineral oil purification, giving stronger adsorption of chlorophyll and impurities where a standard grade would need a higher dosage.
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Bleaching Earth
Low Free Acid Bleaching Earth
Low free acid bleaching earth for speciality and sensitive oils, limiting the rise in free fatty acids and acid-catalysed side reactions during the bleaching step.
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Attapulgite
Attapulgite
Fibrous attapulgite clay used as a component in bleaching and purification blends, where its porous, needle-like structure supports adsorption and the formation of a permeable filter cake.
View productEdible Oil Refining — common questions
What dosage of bleaching earth is used in edible oil refining?
Dosage commonly ranges from about 0.5 % to 2 % of oil weight, and can be higher for heavily coloured or poor-quality crude oils. The right level depends on oil type, pretreatment, target colour and the activity of the clay. Laboratory bleaching tests on your own oil are the reliable way to set the dosage before plant trials.
What is the difference between standard and high activity bleaching earth?
High activity bleaching earth is activated to give greater adsorption capacity, so it removes more chlorophyll, colour and impurities per kilogram. That can lower the dosage needed for difficult oils and reduce oil losses in the filter cake. Standard grades suit routine refining where oil quality is consistent and colour targets are less demanding.
Why choose a low free acid bleaching earth?
Acid-activated clays carry some residual acidity, which can raise free fatty acids or promote unwanted reactions in sensitive oils. A low free acid grade limits this effect, which suits speciality oils, oils intended for physical refining and products where acid-catalysed changes must be kept to a minimum. Confirm the benefit in laboratory bleaching trials.
Can we trial your bleaching earth on our oil?
Yes. Tell us your oil type, crude quality, current bleaching earth, dosage and the colour or impurity targets you work to. We will suggest a grade and send samples, along with the Technical Data Sheet, so your laboratory can run comparative bleaching and filtration tests on your own oil.
Request a quote
Talk to a edible oil refining specialist
Describe your process and current material. We will recommend a grade, share the datasheet and arrange samples for trial.