Process for isomerization of C5—C7 hydrocarbons in light naphtha range

A process for isomerization of C5-C7 hydrocarbons in light naphtha range, the process consisting of:

• a) feeding a light naphtha hydrocarbon feed to a first fractionation column for separating into a first stream, a second stream, and a third stream, wherein the first stream consists of i-pentane, the second stream consists of n-pentane, n-hexane, mono and di-branched isomers of n-hexane and methyl cyclopentane, and the third stream consists of methyl cyclopentane, cyclohexane, benzene and C7 paraffinic/naphthenic hydrocarbons;
• b) mixing the second stream with a recycled middle stream from a second fractionation column, and hydrogen, and feeding to a first isomerization reactor provided with a mixed metal oxide type catalyst;
• c) passing a first effluent obtained from the first isomerization reactor through a first separator to separate hydrogen and a first liquid stream after cooling;
• d) feeding the first liquid stream to a stabilizer for separating dissolved light gases, and a first bottom stream and sending the first bottom stream to the second fractionation column to produce a top stream, the middle stream and a second bottom stream;
• and
• e) mixing the third stream from the first fractionating column with hydrogen and feeding to a second isomerization reactor provided with a mixed metal oxide type catalyst to produce a second effluent which is passed through a second separator to remove hydrogen and obtain a second liquid stream after cooling,
• wherein an isomer product of C5-C7 hydrocarbons in light naphtha range is a mixture of the first stream, the top stream of the second fractionation column, the second bottom stream of the second fractionation column, and the second liquid stream, wherein the hydrogen used in the first isomerization reactor is a combination of a first make-up hydrogen and recycled hydrogen from the first separator, wherein the hydrogen used in the second isomerization reactor is a combination of a second make-up hydrogen and recycled hydrogen from the second separator, wherein the hydrogen from the first separator is passed to a first compressor and recycled to the first isomerization reactor, and wherein the hydrogen from the second separator is passed to a second compressor and recycled to the second isomerization reactor.