Manufacturing and Application of Fatliquor from Castor Oil for Upper Leathers

Abstract

Castor oil is classified as semi-drying oil because it oxidizes on exposure to air,

giving a gummy film, and can be highly sulphated to make it emulsible in water. In

the raw condition it is seldom used in fatliquoring of leathers because crude oil

does not emulsify with water and hence the failure of the fatliquor process. Castor

seeds were collected, sundried, and crushed. Castor oil was leached in a soxhlet

apparatus using hexane as a solvent. An oil content of 28.4%was obtained.

Physical and chemical analysis was carried out to obtain crude castor oil. The

crude castor oil was converted to fatliquor by sulphation using conc sulphuric

acid(98%). The physical and chemical analysis were carried out for the produced

fatliquor and compared with the standards. This study is carried, through extraction

and characterization of castor oil. Normal hexane was used as a solvent for the

extraction process. The characterization analysis revealed that important

parameters, include specific gravity, PH, saponification and iodine values for both

crude and refined castor oil produced, these were compared the ASTM standard

specifications. Sulphated castor oil are added to the leather during re-tannaing

process to lubricate leather fibers and to impart softness, flexibility and hand

feeling. Fatliquors are mainly emulsifyied mixtures, prepared by addition of

phosphate, sulphonate, and sulphite groups etc.Sulphation is one of the methods

used to prepare fatliquor emulsion where sulphuric acid is used. In the present

study, castor oil is extracted from castor beans. The physicochemical properties of

the prepared fatliquor were determined. The fatliquor was applied to leathers in the

re-tannaing process and the strength properties of the resultant upper leather were

assessed through various physical and chemical tests. The results obtained revealed

that castor oil can effectively be used to manufacture fatliquor to be used to lubricate leather in fatliquoring process.