Coconut reactor

Fig. 1.16 C eneral view of the coconut reactor (courtesy of D. Stuerga).

D. Stuerga and P. Pribetich have designed an egg-shaped microwave reactor. Its name has been chosen in relation to its appearance (a black egg which reveals, after opening, a white core). The coconut reactor is described by Fig. 1.16. 

Kim et al. [123] conducted the kinetic study of methane catalytic decomposition over ACs. Several domestic (South Korea) ACs made out of coconut shell and coal were tested as catalysts for methane decomposition at the range of temperatures 750-900°C using a fixed-bed reactor. The authors reported that no significant difference in kinetic behavior of different AC samples was observed despite the differences in their surface area and method of activation. The reaction order was 0.5 for all the AC samples tested and their activation energies were also very close (about 200 kj/mol) regardless of the origin. The ashes derived from AC and coal did not show appreciable catalytic effect on methane decomposition. 

Continuous interesterification processes exist but to date none have been commercialized. Interesterification is generally performed in small batches by specialty processors. An alternate method of increasing interest is directed interesterification using enzymes. The process is generally applied to palm-oil-based materials such as cocoa butter substitutes and to coconut oils. There is some concern about the effectiveness of interesterification with physical refined oils as low levels of FFA must be present or the reaction will not proceed as planned (5). Although not a hazardous process, interesterification is often included in the hydrogenation section of the refinery because of the similarity of the reactors. 

Alkanolamide from Coconut Oil. A 2 1 cocodiethanolamide (CDEA) can be produced using 6 moles of diethanolamine and 1 mole of rehned and bleached coconut oil. The materials are charged with the reactor and a small amount of catalyst (0.25-0.3% sodium methylate or sodium hydroxide) is added. The temperature of the batch is increased to 70-75°C at normal pressure. After 90 min, the reaction is completed. For a 10-t batch, total cycle time from charging the materials, heating them up, allowing the reaction to proceed to completion, and transferring the finished product takes at least 4 h. 

If fatty acid is the starting material, a different operating parameter is used to drive off the water formed during the reaction. If superamide is to be produced, cocomethyl ester and diethanolamine can be used as the starting materials in a mole ratio of 1 1. These materials are charged to the reactor with 0.3-0.5% sodium methylate as the catalyst. The reaction is carried at around 100°C and a vacuum of 4-5.3 kPa for a period of 90-120 min. The reaction temperature can be lowered to 70-75°C by employing a vacuum of less than 4 kPa. The reaction time takes longer to enable the maximum vaporization of the methanol byproduct. The methanol is rectified and recycled for use in the transesterification of the coconut oil to produce the methyl ester. 

Sn-beta, combined with hydrogen peroxide as oxidant, has the potential to substitute classical oxidants, for example peracids, in BV oxidations. As an example, the oxidation of delfone (2 pentylcyclopentanone) to d-decalactone (tetrahydro-6-pentyl-2H-pyran-2-one) is currently achieved using the corrosive peracetic acid. The resultant lactones have a creamy coconut-and peach-like aroma and are important flavor constituents of many types of fruit, and cheese and other dairy products. The lactones are also used in fragrances the two enantiomers have different aromas. Sn-beta was tested for this BV transformation in a stirred reactor. The desired lactone product was obtained in 86% yield in the presence of the Sn-beta catalyst. (302) This result demonstrated clearly that the combination of Sn-beta and hydrogen peroxide is an environmentally friendly alternative to the commonly used organic peracids, even in asymmetric synthesis. Instead of a stoichiometric amount of carboxyHc acid waste, water is produced as a side product from the oxidant. 

Coir fibers are obtained from the husk of the coconut. Coir fiber is generally extracted by mechanical means from the plant [52]. Manilal et al. [52] extracted coir fibers by a closed retting process in an aerobic retting reactor. Bakri and Eichhorn [53] mechanically extracted coir and celery fibers and studied their tensile behaviors in terms of micromechanics. Mothe and Miranda [45] studied the thermal stability and chemical constituent analyses of coir fibers. Khan and Alam [54] investigated the effects of several chemical treatments on the thermal and meachanical properties of coir fibers. Mahato et al. [55] studied the effect of alkalization on the thermal degradation of coir fibers. 

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