Method for purifying acetone

A method for purifying a crude acetone raw material containing low molecular weight impurities, using two columns in sequence comprising the steps of:

• a) feeding the crude acetone raw material into a first column;
• b) adding an aqueous sodium hydroxide solution and an aqueous hydrogen peroxide solution into the first column to form high molecular weight impurities;
• c) removing a top fraction from the first column by distillation to form a bottom fraction comprising an acetone mixture comprising high molecular weight impurities;
• d) feeding the bottom fraction comprising the acetone mixture obtained in step c) to a second rectification column at a charge point on the column;
• e) adding an aqueous sodium hydroxide solution to the second column above the charge point of the bottom fraction fed in step d);
• and
• f) separating a purified acetone from the high molecular weight impurities and removing the purified acetone as a top fraction by distillation in the second column,
• wherein the second rectification column is operated at atmospheric pressure, and wherein the purified acetone has an acetaldehyde level of less than 10 ppm as measured by gas chromatography from a calibration curve obtained using acetaldehyde/acetone standards and a KT-Test time of greater than 8.5 hours, as measured by the SABIC KT-Test method.

A method for purifying a crude acetone raw material containing low molecular weight impurities, using two columns in sequence comprising the steps of:

• a) feeding the crude acetone raw material into a first column;
• b) adding an aqueous sodium hydroxide solution and an aqueous hydrogen peroxide solution into the first column to form high molecular weight impurities;
• c) removing a top fraction from the first column by distillation to form a bottom fraction comprising an acetone mixture comprising high molecular weight impurities;
• d) feeding the bottom fraction comprising the acetone mixture obtained in step c) to a second rectification column at a charge point on the column;
• e) adding an aqueous sodium hydroxide solution to the second column above the charge point of the bottom fraction fed in step d);
• and
• f) separating a purified acetone from the high molecular weight impurities and removing the purified acetone as a top fraction by distillation in the second column,
• wherein the second rectification column is operated at atmospheric pressure, wherein the weight ratios of the sodium hydroxide solution to the hydrogen peroxide solution are between 1:0.5 to 1:10, and wherein the weight ratios of the sodium hydroxide solution in the first rectification column to the sodium hydroxide solution in the second rectification column are between 1:0.1 to 1:5, and wherein the purified acetone has an acetaldehyde level of less than 10 ppm as measured by gas chromatography from a calibration curve obtained using acetaldehyde/acetone standards and a KT-Test time of greater than 8.5 hours, as measured by the SABIC KT-Test method.