a. Devise a LLE extraction method that could be used to isolate cocaine (pKa=8.6

Question

a. Devise a LLE extraction method that could be used to isolate cocaine (pKa=8.6) from methamphetamine (pKa=9.9) in a mixture of the drugs with powdered sugar, and cornstarch. Give details for the extraction design including the solvent(s) you will be using. Justify each step and separation.

There may be more than one correct answer, as long as your reasoning makes sense and your extraction procedure has a good probability of separating the compounds.

B. Design the isolation of cocaine and methamphetamine from the mixture now using SPE.

Explanation / Answer

clearly, there is a gap between cocaine + methamphetamine

pKcoca < pH < pKmeth

8.6 < pH < 9.9

then,

Set pH between that

cocaine will lack of H+ ions while meth will be rich in H+

Expect cocaine to turn "molecular" since NH+ --> N and H+

Expect meth to tun "ionic" since NH + H+ --> NH2+

so

Extract molecular sample in nonpolar solvent

Extract ionic sampe in water--> inic aqueous solution

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.