I\'m trying to separate 50% fluorenone, 40% methyl 4-aminobenzoate and 10% 1,4 d
ID: 998114 • Letter: I
Question
I'm trying to separate 50% fluorenone, 40% methyl 4-aminobenzoate and 10% 1,4 dibromobenzene.
The solvents avalailable are:
1M & 6M NaOH, 1M & 6M HCl, 1M NaHCO3, Saturated NaCl, Diethyl ehter, 95% ethanol, methanol, isopropyl alcohol, acetone, hexane, toluene, methylchloride and granular anhydrous sodium sulfate.
I understand that acid-base extraction that when we use HCl to extract, we will separate the methyl 4-aminobenzoate and get fluorenone and 1,4 dibromobenzene. But how can i separate these two compounds when they both similar in polarity, melting point , and neutral. In other words, what solven could i use to separate these two neutral compounds
Explanation / Answer
Fluorenone and 1,4 dibromobenzene have similar polarity but not same polarity. We can use fractional crystallization to separate these two. We will have to determine suitable solvent/ solvent system by trial and error method.
We will dissolve the mixture of 1,4 dibromobenzene and fluorenone in a suitable solvent system and make a homogenous saturated solution and sufficiently high temperature. Then we will slowly cool the solution and also reduce the polarity of the solvent system by dropwise addition of non polar solvent. This we will carry out till a point when one of the two components crystallizes out. Then we will filter the solution and then further continue cooling and lowering polarity till second component crystallizes out. We will again filter the solution.