Method for manufacturing succinic acid

A method for preparing succinic acid comprising the steps of:

• subjecting a carbon source to a fermentation step to form succinic acid, in which the fermentation step comprises the steps of fermenting a carbon source by means of a micro-organism capable of producing succinic acid in a fermentation broth to form succinic acid and neutralizing at least part of the succinic acid by adding a magnesium base selected from magnesium oxide, magnesium hydroxide, magnesium carbonate, and magnesium bicarbonate, thereby obtaining a magnesium succinate solution;
• providing the aqueous magnesium succinate solution, optionally after a biomass removal step and/or a concentration step, to an acidification step, wherein the magnesium succinate solution is acidified by the addition of hydrogen chloride, thereby obtaining an aqueous solution comprising succinic acid and magnesium chloride;
• subjecting an aqueous solution comprising succinic acid and magnesium chloride derived from the acidification step to a treatment step with active carbon;
• precipitating succinic acid from an aqueous mixture comprising succinic acid and magnesium chloride resulting from the active carbon treatment step in a precipitation step to form solid succinic acid and a magnesium chloride solution;
• separating the solid succinic acid from the magnesium chloride solution;
• subjecting the magnesium chloride solution to a thermal decomposition at a temperature of at least 300° C., thereby decomposing the magnesium chloride to magnesium oxide and hydrogen chloride;
• and
• recycling the hydrogen chloride generated in the thermal decomposition step to the acidification step.