Ye Rong, Zhao Zirui, Gao Rong, Wan Junfen, Cao Xuejun
State Key Laboratory of Bioreactor Engineering, Department of Bioengineering, East China University of Science & Technology, 130 Meilong Road, Shanghai 200237, China.
ACS Omega. 2021 Dec 30;7(1):683-687. doi: 10.1021/acsomega.1c05316. eCollection 2022 Jan 11.
Citric acid is mainly produced in the fermentation industry, which needs complex processes and produces a high amount of CaSO as waste. In this study, CO has been used to convert calcium citrate to citric acid and CaCO by controlling the reaction parameters (reactants ratio, temperature, and pressure). The CaCO produced in this conversion could further be used in the fermentation industry for citric acid production. The transformation condition has been optimized by controlling temperature, pressure, reaction time, and mass ratio of calcium citrate and water. The highest conversion could reach up to 94.7% under optimal experimental conditions of 18 MPa of pressure, 65 °C of reaction temperature, 4 h of reaction time, and 2 g/L of calcium citrate/water suspension solution. This method features simple process, easy separation of citric acid, and environmentally friendly process, which could be a potentially alternative route for downstream treatment in fermentation production of citric acid.
柠檬酸主要在发酵工业中生产，这需要复杂的工艺，并且会产生大量的硫酸钙作为废物。在本研究中，通过控制反应参数（反应物比例、温度和压力），利用一氧化碳将柠檬酸钙转化为柠檬酸和碳酸钙。这种转化过程中产生的碳酸钙可进一步用于发酵工业生产柠檬酸。通过控制温度、压力、反应时间以及柠檬酸钙与水的质量比，对转化条件进行了优化。在压力为18兆帕、反应温度为65℃、反应时间为4小时以及柠檬酸钙/水悬浮液浓度为2克/升的最佳实验条件下，最高转化率可达94.7%。该方法具有工艺简单、柠檬酸易于分离以及环境友好等特点，可能成为柠檬酸发酵生产下游处理的一种潜在替代途径。
