Technical Cashew Nut Shell Liquid Research Articles

Ozonization of phenols from Anacardium occidentale (cashew)

AbstractThe phenolic lipid components cardanol and cardol, obtained from heat‐processed technical cashew nutshell liquid from Anacardium occidentale, and anacardic acid from the natural product, each containing monoene, diene, and triene constituents, were ozonized. The ozonides were reduced chemically and catalytically to give 8‐(3‐hydroxyphenyl)octanal, 8‐(3,5‐dihydroxyphenyl)octanal, and 8‐(3‐hydroxy‐2‐carboxyphenyl)octanal, respectively, together with formaldehyde, malondialdehyde, butanal, and heptanal in each case. Reduction of the 8‐(3‐hydroxyphenyl)octanal, which was synthesized from 3‐benzyloxybenzaldehyde, gave 3‐octylphenol. Oxidation of the aldehyde with potassium permanganate gave 8‐(3‐hydroxyphenyl)octanoic acid, and reduction with sodium borohydride yielded 8‐(3‐hydroxyphenyl)octanol. For comparison, the trans‐diols of cardanol were prepared by treatment of cardanol with peroxyformic acid and cleaved by periodate oxidation to give an alternative route to 8‐(3‐hydroxyphenyl)octanal but in lower yield. Likewise, the cis‐diols were obtained with potassium permanganate and cleaved without isolation to give the same product in lower yield compared with ozonization.

Biologically Active Derivatives of Cardanol: Antifungal 8-aryloctanoic Acids

Abstract Nine antifungal 8-aryl-octanoic acids were prepared using cardanol, the main constituent of technical cashew nut shell liquid (CNSL), as starting material. The structures of the compounds were confirmed by spectral analysis.

The extraction of natural cashew nut‐shell liquid from the cashew nut (Anacardium occidentale)

AbstractIn the two‐stage recovery of natural cashew nut‐shell liquid (CNSL) by solvent extraction, the overall yields from half‐shells obtained by mechanical cutting and from chilled fragmented shells (to solidify the phenols) by manual processing are identical, indicating that no physical loss of phenolic material occurs in the mechanical process. At the first stage, prior to comminution, the yield from intact half‐shells of mechanical origin is considerably less than that from manually processed shells due to extensive internal fracturing of the shell structure and greater solvent penetration in the latter case. Static solvent extraction of macerated shells gave the same yield as Soxhlet extraction, but the filtration stage was difficult and large volumes of solvent were required. Soxhlet solvent extraction or ultrasound/solvent extraction of manually processed shells at ambient temperature gave similar yields and economy in solvent usage. Both were much superior to mechanical agitation. By catalyzed decarboxylation of the recovered natural CNSL an almost theoretical yield (25%) of phenolic lipid rich in cardanol was obtained, which is considerably higher than that (10%) in the traditional recovery of technical CNSL by the hot oil bath industrial method. Natural CNSL contains a predominant amount of anacardic acid and represents a novel phenolic lipid source. Chemical reduction with air/aqueous hydrazine gave saturated natural CNSL. Polymerization of natural CNSL was effected in alkaline solution with paraformaldehyde.

Practical liquid chromatographic separation of the phenols in technical cashew nutshell liquid fromAnacardium occidentale

AbstractThe practical separation of cardanol from technical cashew nutshell liquid or its distillate has been effected by liquid chromatography on Silica Gel H 60 (TLC type) with solute/absorbent in the range 1∶5–1∶6. Concentrates of the monoene, diene and triene constituents of cardanol have been prepared by argentation liquid chromatography on Silica Gel H 60 with dry incorporation of 15% silver nitrate. The present use of pressurized columns was made prior to the advent of flash chromatography.

Long‐chain phenols. Part 231 practical separations of the component phenols in technical cashew nut‐shell liquid (Anacardium occidentale): Distillation procedures for obtaining cardanol

AbstractThe separation of cardanol from cardol and coloured impurities in technical cashew nut‐shell liquid (CNSL) has been examined by molecular and vacuum distillation and the purity of fractions carefully assessed by thin‐layer, gas‐liquid and high‐performance liquid chromatographic analysis. A small 10‐stage rotary still (Vitamins‐Watt type) produced cardanol (99%) in approx. 58% yield with a total phenolic recovery between 80 and 90%. A falling film single‐stage still (Edwards type) gave less pure cardanol and a good total phenolic recovery. Prerequisites to avoid polymerisation in conventional vacuum distillation were wide‐bore vacuum equipment and a nitrogen leak. Excessive flask and surface temperatures resulted in only a 70% total phenolic recovery, the cardanol fractions being approx. 90% pure. With a lower flask and surface temperature, by the use of a liquid‐heating bath, the total phenolic recoveries were better than those in molecular distillation and the cardanol fractions (60 %) were 90–95 % pure. The procedure of slow addition enabled the scale of apparatus to be reduced. The distillation of hydrogenated technical CNSL appeared less satisfactory than that of the unsaturated material.

Long-chain phenols : XXI. quantitative analysis of the phenolic lipids in technical cashew nut-shell liquid, from anacardium occidentale, by high-performance liquid chromatography

The novel separation of the constituent phenols in technical cashew nut-shell liquid from the industrial processing of Anacardium occidentale has been effected by high-performance liquid chromatography. The adsorption mode on columns of 5-μm and 10-μm Partisil and the reversed-phase partition mode with 5-μm and 10-μm Spherisorb bonded with octadecylsilane have been investigated. Determination of relative molar response values for the main constituent phenols and the use of an internal standard have led to a quantitative procedure by isocratic elution under reversed-phase partition, preferably with the solvent acetonitrile-water. Gradient elution with tetrahydrofuran and acetonitrile has also enabled the polymeric material to be estimated in the various types of technical cashew nut-shell liquid examined.

Compositional studies on technical cashew nutshell liquid (cnsl) by chromatography and mass spectroscopy

AbstractThe composition of technical cashew nutshell liquid (CNSL), Anacardium occidentale, from four different sources has been examined. The C15 component phenols cardanol, cardol, 2‐methyl cardol, and traces of anacardic acid have been determined by gas liquid chromatography (GLC), after hydrogenation and methylation, on the stationary phases Dexsil 300, SE52, SE30, and OV17, or alternatively the acetylated (unsaturated) phenols on Dexsil 300, SE52, or SE30. After thin layer chromatographic (TLC) separation of the component phenols, their saturated (15:0), monoene (15:1), diene (15:2), and triene (15:3) constituents have been determined by mass spectrometry (MS). In both the GLC and the MS procedures, the results have been corrected for differing relative responses. The more highly polymeric material present in technical CNSL from different sources has been determined by molecular distillation and by TLC. The fractions obtained by molecular distillation have been analyzed by GLC, the results of which show there is present some low polymeric material less volatile than the C15 component phenols, but the major portion of technical CNSL is volatile and can be analyzed by GLC.

Long-Chain Phenols : IX. Compositional studies on the unsaturated phenols of anacardium occidentale (cashew nut-shell liquid)

An extensive gas chromatographic investigation of alternative stationary phases to polyethyleneglycol adipate has revealed two which are suitable for the quantitative analysis of hydrogenated and methylated natural and technical cashew nut-shell liquid. Relative response factors have been obtained for the saturated (15:0), monoene (15:1), diene (15:2) and triene (15:3) constituents of all the component phenols and have been used to correct the gas chromatographic results described in Part IV. A comparison has been drawn between the ionisation processes in the flame ionisation detector and in mass spectrometry.

Determination of the component phenols in natural and technical cashew nut-shell liquid by gas-liquid chromatography

Determination of the component phenols in natural and technical cashew nut-shell liquid by gas-liquid chromatography