How to Extract Citric Acid From a Grapefuit

Instructions

• 1

  Put on gloves and use precaution when handling all solutions, and when carrying out this procedure.

• 2

  Measure 90 milliliters of the grapefruit juice into a 250-milliliter beaker. Add 10 percent sodium hydroxide solution until there is a distinct change in color.

• 3

  Strain the liquid to remove large pieces of pulp. Place filter paper on Buchner funnel and filter solution. Measure the amount of clear filtrate and transfer into a beaker.

• 4

  Add 5 milliliters of 10 percent calcium chloride for each 10 milliliters of filtrate, and boil the solution to precipitate calcium citrate.

• 5

  Separate the precipitate by filtering the hot solution through the Buchner funnel. Rinse the calcium citrate with hot water and transfer contents to a new beaker.

• 6

  Dissolve the calcium citrate precipitate in a small volume of cold water. Boil the solution to precipitate the calcium citrate again. Repeat the filtration step to separate calcium citrate and air dry.

• 7

  Carefully add sulfuric acid to the air dried calcium citrate in a beaker, until a calcium sulfate salt is formed, leaving the citric acid in the solution.

• 8

  Concentrate the solution of citric acid in a water bath. Air dry the solution to obtain crystals of citric acid.