Natural clays have the strongest structures that resist attrition that may occur when bleaching materials are pneumatically conveyed & when they pass through pumps.
Acid-Activated Bleaching Earths have silica fronds that are formed during the acid-activation process. Hash handling may cause these fronds to break off resulting in loss of bleaching performance and may adversely affect filtration performance.
Activated Carbons are relatively soft materials and are most susceptible to particle-size deterioration during handling. The production of fines, and resulting fines breakthrough are important factors. The abrasion resistance is thus an important factor in the selection of activated carbons. We utilize steam-activated that have similar structural strength to acid-activated clays.
|COMPARISON OF THE PROPERTIES OF NATURAL BLEACHING EARTH,
|ACID-ACTIVATED BLEACHING EARTH AND ACTIVATED CARBON
Action of Absorbent
Natural Bleaching Earths & Activated Carbons primarily remove impurities by absorption, without affecting the other properties of the oil being processed. We utilize a blend of different activated carbons in order to achieve the desired structural strength and impurity removal performance.
Acid-Activated Bleaching Earths function as absorbents, and also have greater ion-exchange capacity and catalytic properties as compared with natural bleaching earths and activated carbons. Acid catalytic cracking can reduce the size of larger molecules, and protonation can cause structural changes that make certain pigments invisible.
Natural Bleaching Earths, Acid-Activated Bleaching Earths and Activated Carbons all have different properties. For this reason, the refiner must select which bleaching earth, or bleaching earth blended with activated carbon that is most appropriate for the oil being refined, to meet their desired properties for the fully refined oil. Our team are on hand to assist you with your grade selection.
Our bleaching earths are utilized to successfully refine a range of chemically- and physically- refined edible oils, including palm oil & its fractions, coconut oil, soyabean oil, Canola/rapeseed oil, groundnut oil, mustard seed oil, rice bran oil, cottonseed oil, and corn oil.
ENHANCING NATURE’S POTENTIAL
Natural Bleach’s “NB14000 Series” of Natural Non-Acidic Bleaching Earths are activated by physical processing natural clays to develop enhanced absorbent properties. In the process the clays are transformed into granules or free-flowing powders.
No chemicals are utilized in the processing, and no wastes are generated.
“NB14000 Series” bleaching earths act primarily as absorbents, removing impurities from the oil being processed, without otherwise affecting the oil. This distinguishes the “NB14000 Series of bleaching earths from classical acid-activated bleaching earths that can modify the oil through cracking and isomerization reactions.
PRESERVES NUTRITIONAL VALUE
“NB14000 Series” bleaching earths are absorbents that remove oxidized materials, gums, trace metals and pigments from the oil during the bleaching process.
The absence of catalytic activity preserves the structure of the oil, as there is no double bond shifting or conjugation that would cause a reduction in stability of the oil.
The lack of catalytic activity also means that harmful Trans-isomers are Not formed when utilizing “NB14000 Series” bleaching earth.
This important feature of the “NB14000 Series” of bleaching earths can be utilized in the processing of crude palm oil.
The Carotenoids can be substantially preserved in the oil during the bleaching stage, enabling stable and nutritionally beneficial “Red Palm Oil” to be produced, after deodorizing under mild conditions, or low-coloured oil under normal high-temperature deodorization.
Since the clays that we utilize for the manufacture of our “NB14000 Series” bleaching earths have never been exposed to sea water, they are naturally very low in chloride and chlorine content. This greatly assists those refiners who wish to produce oils with the lowest possible contents of the harmful compounds known as 3-MCPDs.
Activated carbon blends have additional benefits in that they have enhanced removal properties for organo-chlorine compounds, including dioxins.
TYPICAL COMPOSITION OF MOST POPULAR GRADES