Ácido behénico
Nombre INCI: Behenic Acid. También: Ácido docosanoico.
Calcular una pastilla 100 % de ácido behénico
Eso es estequiometría sobre una composición medida y no una suposición, y está casi tan bien determinado como una cifra publicada: comprobado contra los 35 aceites del Codex en los que los dos campos vienen de la misma norma, el error mediano del método es del 0,90 % y su percentil 90 del 2,74 %, sin sesgo apreciable. La página de fórmulas enseña las cuentas. Si tiene un certificado de análisis de su lote, introduzca su valor medido en la calculadora y esta estimación se deja de lado.
Valores publicados
| Índice de saponificación | no publicado |
| Derivado de la composición | 166.2 ± 3 % mg KOH/g |
| Usado por la calculadora | 166.2 mg KOH/g (derivado) |
| SAP para NaOH | 0.1185 g/g |
| Índice de yodo | — |
| INS (SAP − índice de yodo) | — |
| Punto de fusión | 74–79 °C |
| Materia insaponificable | — |
Una pastilla hecha 100 % de ácido behénico
Cualidades convencionales sumadas a partir de los grupos de ácidos grasos; una pastilla de un solo aceite es una referencia, no una receta.
Perfil de ácidos grasos
| Ácido graso | Rango publicado, % | Usado | |
|---|---|---|---|
| Ácido araquídico | C20:0 · saturados | 10 | 10.0 |
| Ácido behénico | C22:0 · saturados | 85 | 85.0 |
De dónde salen estos números
Las notas con fuente que aparecen debajo, y los títulos de los documentos que citan, se mantienen en su idioma original. Una cita traducida no se puede consultar, y un resumen técnico traducido ya no es el resumen que se contrastó con el documento.
Chemical Properties table: Melting Point, method USP 741, 74-79 C; Acid Value, method USP 401, 161-169 mg KOH/g; Color, visual, White. Regulatory: INCI Behenic Acid, CAS 112-85-6, EINECS 204-010-8, manufactured Watertown, Connecticut. No saponification value, iodine value or fatty-acid composition is published on the page.
Product Specification table: product name LUNAC BA, chemical name Behenic acid, INCI name BEHENIC ACID, appearance granule, typical fatty acid composition C20 10 %, C22 85 %, producer region Asia. No acid, saponification or iodine value is given.
Specifications: Appearance (Color) white to pale cream or pale yellow; Assay (Silylated GC) 83.0 % min; Comment C24 = 0-3 %, C26 = 0-0.5 %; Melting Point (clear melt) 74-82 C; Identification (FTIR) conforms. CAS 112-85-6, C22H44O2, 340.592 g/mol.
Purity >99 %, CAS 112-85-6, C22H44O2, MW 340.58, solid, supplied neat. Cited only to establish that a >99 % grade exists; no titration values are published.
No allowed primary document publishes a saponification value for behenic acid, so sapKohMgPerG is null. Checked and empty-handed: Wilmar's fractionated fatty acid tables stop at C18 and have no C22 grade, Emery's oleobasics pages cover only stearic, oleic, tallow, vegetable, pelargonic and azelaic acids, Oleon's RADIACID range prints acid values but never a saponification value and has no C22 cut, KLK OLEO names three behenic grades (PALMERA A8522, A8922, A9322) but publishes no figures for them, NOF lists NAA-222 and NAA-222S with no specification, and Sigma-Aldrich/Merck, Thermo Scientific and Larodan publish purity only. What is published, and what this record holds: Koster Keunen's Behenic Acid (their code 220, described as a highly pure grade) gives melting point 74-79 C by USP <741> and acid value 161-169 mg KOH/g by USP <401>, colour white. Kao's LUNAC BA gives a typical composition of C20 10 % and C22 85 %; the remaining ~5 % is not itemised, which is why the profile here sums to 95. Thermo Scientific's technical 85 % grade specifies assay (silylated GC) 83.0 % min with C24 0-3 % and C26 0-0.5 % and a clear melt at 74-82 C, and Larodan's research-grade docosanoic acid is >99 %. On the arithmetic: a free fatty acid takes one KOH per molecule, so pure C22:0 (M 340.58) is 56106 / 340.58 = 164.7 mg KOH/g and the LUNAC BA composition works out at about 166 - both inside Koster Keunen's acid-value band, and for a saturated straight-chain acid the saponification value runs only about 1 mg KOH/g above the acid value (Wilmar prints both figures for its C8, C10, C12, C14 and C16 cuts and the gap is 1 in every one of them; it is 2 on their oleic acid). So 161-169 is a safe working number in practice, but it is an acid value and this record will not file it as a saponification value. Ricinoleic acid is the reason for the caution: the same kind of TDS prints acid value 165 and saponification value 185-190 for the same material, because the hydroxyl esterifies and the two titrations stop measuring the same thing. Iodine value is null - nobody publishes one, though a fully saturated acid must be near zero. In soap, behenic behaves like a longer, harder, slower stearic: it raises the melting point and hardness and dissolves reluctantly, so past a few percent it tends to leave a waxy bar with poor lather. Both Kao and Koster Keunen print the INCI name as Behenic Acid, so that field is sourced; the sodium and potassium salt names were not, and CosIng was not consulted, so saponifiedInci is null.
Esta ficha forma parte de la base de datos abierta de ingredientes (ODbL). ¿Ha encontrado un error o una fuente primaria mejor? El conjunto de datos está en GitHub; las correcciones con un enlace al documento son bienvenidas.