Effect of operating parameters on precipitation for recovery of lactic acid from calcium lactate fermentation broth

Abstract

Precipitation is a simple, efficient method for separating and recovering lactic acid in the form of calcium lactate from fermentation broth by adding sulfuric acid. Major operating parameters of the recovery step as well as the temperature of concentration of the recovered lactic acid solution and the type and amount of adsorbent used for pigment (color) removal were optimized. When the molar ratio of calcium lactate to sulfuric acid was 1 : 1 and the pH was increased to a value greater than the pKa (3.86), calcium sulfate was precipitated and could be removed more effectively, allowing for more efficient separation and recovery of supernatant lactic acid. Precipitation could be facilitated by adding calcium lactate solution with mixing (up to 220 rpm) and was completed in over 18 h. The optimal temperature for the concentration of lactic acid recovered from the supernatant after removing the precipitated calcium sulfate was found to be 90 o C in terms of the time required for concentration and the stability of the product. Activated carbon (SX-PLUS, 9 g/L) was most effective as an adsorbent for color removal from the recovered lactic acid. Under the optimized precipitation conditions, an overall yield of 92% of lactic acid from fermentation broth could be achieved.

Separation of lactic acid and recovery of salt-ions from fermentation broth

“…Nevertheless, separation of lactic acid and impurities was satisfactory and almost all of the loaded lactic acid was found in the BV‐fractions when Amberlite FPA 53 was used together with 12.5 mmol L −1 H 2 SO 4 as eluent. The yield of more than 90% lactic acid was highly comparable with the yield obtained by the state‐of‐the‐art method: precipitation of calcium lactate and recovery of lactic acid by adding H 2 SO 4 under formation of large amounts of CaSO 4 . A decrease in flow rate and sample volume loaded may even improve the recovery yield and purity as found by Tong et al for the separation of lactic acid from fermentation broth using Amberlite IRA‐92.…”

Lactic Acid Production to Purification: A Review

“…Otherwise, the separation steps are widely discussed in literature, such as precipitation (Rauch et al 1960;Min et al 2011;Kwak et al 2012;Nakano et al 2012), solvent extraction (Malmary et al 2000;Wasewar et al 2002;Matsumoto et al 2003;Yankov et al 2004;Alkaya et al 2009;Krzyzaniak et al 2013), membrane separation processes, and others. Membrane separation processes that have been studied include reverse osmosis, electrodialysis, and ultrafiltration (Kim and Moon 2001;Choi et al 2002;Madzingaidzo et al 2002;Li and Shahbazi 2006;González et al 2008;Ecker et al 2012;Lu et al 2012;Ramchandran et al 2012;Sikder et al 2012;Dey and Pal 2013;Pal and Dey 2013;Wang et al 2014).…”

Separation and Purification Technologies for Lactic Acid – A Brief Review

“…Min et al 2011 Multiple crystallizations in order to obtain high purity lactic acid Substrate: not indicated Microorganism: not indicated…”