Entrapment In Azeotrope

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There are two way of cell immobilized is under consideration which are entrapment in calcium alginate or adsorption on ceramic beads. Both way is feasible in lab-scale and pilot-scale production of ethanol. However, according to research, adsorption on ceramics beads is a better way because alginate beads may arise with some problem such as gel degradation and high cost of raw material and the relative complexity of preparation of the biocatalysts (carrier-cell) with respect to the operative lifetime of the process. Entrapment in calcium alginate gel Entrapment in calcium alginate gel has been one of the most used matrices for whole cell entrapment due to its simplicity and non-toxic character. It is a cell-entrapment technique in order to…show more content…
The amount of ethanol recovered was used to determine the yield of ethanol from the reactors. A customized distillation section was used to recover an azeotropic ethanol/water mixture. Ethanol forms an azeotrope with water. Azeotrope is a term used to describe a constant boiling mixture. This means that an azeotrope is a mixture of two or more pure compounds in such a ratio that its composition cannot be changed by simple distillation. This is because when an azeotrope is boiled, the resulting vapor has the same ratio of constituents as the mixture of liquids. The composition of the ethanol-water azeotrope is 95.6% ethanol and 4.4% water (by weight). The composition of the ethanol-water azeotrope is 95.6% ethanol and 4.4% water (by weight). Ethanol boils at 78.4 ˚C, water at 100 ˚C and the azeotrope at 78.1˚C. This system is typical for separating two component feed into relatively pure overhead product containing the lower boiling component and bottoms product containing primarily the higher boiling component of the feed. The lower boiling component is the ethanol/water azeotrope and the higher boiling component is water in the ethanol/water system. The part of the packed tower below the feed point is the stripper. The stripper is the hottest section of the tower and the ethanol rich stream is vaporized and goes up the column. The ethanol rich vapor continues to rise up the rectifying section of the column where it contacts and increases the purity of the richer ethanol stream as it comes down the column. The overhead is the lowest boiling stream, which is the azeotrope in this case. This results in a constant temperature of about 78 degrees ˚C in the
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