Deacidification of high acidic rubber seed oil by reesterification with glycerol

Some studies have shown that rubber seed oil (RSO) from the seed of rubber tree (hevea brasiliensis)has potential technical applications. However, the high free fatty acid (FFA) associated with the oil may be a limiting factor in its applications. In this study, crude rubber seed oil (RSO) containing 37.69% FFA was deacidified using 4.3-5.6% of glycerol. The reactions were carried out at a pressure of 20mmHg in the presence of zinc dust and zinc chloride catalysts added separately at high temperature (150 – 2500C). The progress of the reaction was monitored by determining the FFA at various time intervals.The FFA content in the RSO was reduced to 1.5% in six hours when 4.3% glycerol was used with zinc dust at a temperature of 2000C while the triglycerides content of the oil increased from 40.32% in the crude oil to 80.62% in the deacidified RSO. The study showed that this process is effective in the deacidification of RSO without loss of neutral glycerides as in alkali neutralization

Synthesis and Characterization of Vulcanized Vegetable Oil from Rubber Seed Oil

Vulcanized vegetable oil (VVO) is a product synthesized from unsaturated vegetable oil and a vulcanizing agent such as sulphur. It is used in rubber industry as processing aid and is imported into Nigeria whereas there are potential plant oils such as rubber seed oil (RSO) locally available in the country for its synthesis. Rubber seed oil is obtained from the seeds of the rubber tree (hevea brasiliensis) and are in abundance in Nigeria but unexploited. Its use in the synthesis of VVO was investigated by using sulphur as the vulcanizing agent. The effects of various doses of additives such as iodine, magnesium oxide, sodium carbonate, 2-mercaptobenzothioazole and zinc diethyldithiocarbonate on the vulcanization process were investigated. The vulcanized rubber seed oil (VRSO) obtained was characterized in terms of hardness, free sulphur, ash content and acetone extract. The type of vulcanized oil produced from rubber seed oil was found to depend on the level of sulphur and additive used. As the level of sulphur used in the synthesis without additives was increased from 15wt% to 30wt% of oil, the gel time was reduced from 35minutes to 14minutes and the physical properties of the VRSO improved. The use of some of the additives markedly affected the gel time particularly magnesium oxide which at 10wt% and 30wt% sulphur loading reduced gel time to 6minutes while some others seemed to have little effect on the gel time. The study shows that VVO can be produced from RSO when the right combination of additives is used instead of when sulphur is used separately

Considerations of the extraction process and potential technical applications of Nigerian rubber seed oil

Rubber seeds from the rubber tree (hevea brasiliensis) are in abundance in Nigeria from which nonedible oil could be obtained. However, the seeds are wasted in the rubber plantations annually even though the extractable oil has potential technical applications. If the full potentials of the oil are to be realized, there is need to have a data base information on the oil extraction process and its properties. Rubber seeds were collected from different rubber clones and extracted first by n-hexane to determine the yield characteristics. Second, the seeds were extracted by a hydraulic press at varied operating conditions: pressure range (5-8MPa), temperatures, 40-90ºC; and moisture content, 7-16%. The effect of particle size and other operating variables on oil yield were studied. The physico-chemical properties of the extracted oil were evaluated. It was found that the percentage oil yield from the seeds of the rubber clone NIG800 at 45.03% was higher than the yield from other clones; GTI (40.21%) and RRIM 707 (38.42%) when the particle size of 1.16 mm was used. Oil yield increased with increase in temperature and pressure. Maximum oil yield was obtained during mechanical pressing at a moisture content of 10% (wt), temperature of 70ºC and pressure of 8MPa. The physicochemical characteristics of the oil showed high incidence of free fatty acid (FFA) of 37.96% (wt) and the high iodine value (IV) of 142.45 is indicative of the presence of high unsaturation. Rubber seed oil could therefore serve as semi-drying oil used in ingredients for surface coating and in the formulation of products where the presence of unsaturation is important

Application of ground scrap tyre rubbers in asphalt concrete pavements

333-338 A laboratory scale evaluation of the feasibility of using ground rubber from scrap tyres in dry process hot-mix asphalt concrete used for road pavement was investigated. The rubber to asphalt ratio (by weight) of the specimens that was initially kept constant at 0.2 was subsequently varied from 0.1 to 0.5 using different rubber particle sizes. Some specimens were cured at ambient temperature, while others were soaked in water inside a curing tank, for a period of 28-days in the laboratory. The Marshall method was used to prepare both conventional and rubberized asphalt concrete specimens. The indirect tensile testing machine was used in the measurements of mechanical properties of all specimens. The results from the study show that the rubberized asphalt concrete mix has much better mechanical properties than the conventional one: the tensile strength of the specimens for example, increased from 1.82 103 to 2.04 103 kPa as the rubber to asphalt ratio increased from 0.1 to 0.3. Similar trends were observed in compressive and tensile moduli. The mechanical properties of rubberized specimens cured in air and those soaked in water were not significantly different (P>0.05). However, the conventional concrete especially those soaked in water showed inferior mechanical properties. The rubber particle size of 0.60 mm had the best mechanical properties while that of particle size 2.36 mm has the poorest mechanical properties. </smarttagtype