What is the cardanol?
The cardanol is a phenolic lipid obtained from anacardic acid, the main component of cashew nutshell liquid (CNSL), a byproduct of cashew nut processing.
Cardanol based resins posses an outstanding resistance to softening action of mineral oil and high resistance to acids alkalies, antimicrobial property termite and insect resistance etc. Contributes to improved flexibility, good drying after banking, high electric insulation properties and thermal stability. Amenability to chemical modification to effect desirable changes so as to get specific properties for making tailor-made polymers of high value, thus the structural changes could be effected at the hydroxyl group, on the aromatic ring and on the side chain. These properties make Cardanol an effective substitute for the petroleum-based phenol.
In Cashew shell have 20 % CNSL content, In CNSL contains 60-65% cardanol, 2-10% cardol, 10-15% oligomers/polymers and 0-2% 2-methylcardanol and anacardic acid. The process according to the invention provides a color-stable composition containing cardanol and cardol. This composition is not only color-stable in storage, the phenalkamines produced from it are also. In addition, the composition is distinguished by the fact that it has better dermatological compatibility than known commercially available products, so that handling and transportation are safer. In a preferred embodiment, the main fraction of step 3 of the process according to the invention is after-treated with small quantities of adsorbents and/or reducing agents.
Specifications of cardanol:
How about application of cardanol?
The products obtained from CARDANOL have many advantages over these manufactured from other substituted phenols as the chemical industry in resins, coatings, frictional materials, and surfactants used as pigment dispersants for water-based inks. It is used to make phenalkamines, which are used as curing agents for the durable epoxy coatings used on concrete floors, electrical Insulating, Varnishes, Brake lining, clutch facings, Lacquers, Pesticides, Rubber compounding, Adhesives, Wax substitutes, Mineral oil additives, Azo Dyes …
How is Cardanol made?
The Cardanol is processing from cashew shell oil (Raw cashew nut shell liquid) one byproduct of cashew processing factory
Cardanol process flowchart: Cashew shell -> pressing oil -> Filtering -> Refining CNSL -> Refining Cardanol.
Cardnol is distilled from Cashew Nut Shell Liquid. A batch of Decarboxylated CNSL is heated to 280degree celcius under Vaccum in a reactor. After few minutes of heating the vapours of Cardanol come into the condenser where it is cooled using suitable coolant to convert the vapour into liquid.
The liquid is collected into a reciever. The process runs for a fixed time after which the receivers and reactors are emptied and fresh batch is started. The Cardanol is filled in tanks or barrels and Residol in barrels after few minutes of cooling.
Samples are drawn for preliminary testing of Colour, Viscosity and pH.
Cashew nut shell liquid from different sources is purchased and stored separately for distillation.
Cashew nut shell liquid is measured using a batch tank and taken into reactor where it is distilled under vacuum at 280 degree celcius.
After the stipulated batch time , Cardanol (Grade 2) is drained from the receiver and stored in vacuum tanks or packed in drums as required . Residol is drained from the reactor into a cooling tank and stored in MS drums .
Some customers prefer double distilled cardanol also known as Grade 1 Cardanol. This is manufatured by re distilling the Cardanol at low temperature under vacuum. The distillate is almost colourless liquid and has application is many products like PU resins etc.
Residol is a thick viscous liquid formed due to polymerisation on non Cardanol components in Cashew Nut Shell Liquid . Residol in cold conditions is highly viscous and often during winters requires external heating of drums to discharge the residol. To avoid this few manufacturers prefer residol to be diluted with cashew nut shell liquid . Depending upon the viscosity requirement of customers , appropriate amount of CNSL is added.
MEKONG TECH GROUP is designed and manufactured complete turkey for CNSL & Cardanol processing plant, Can refer CNSL processing plant as below:
Cashew shell pressing machine
CNSL processing machine
Cardanol processing machine
