【作者】 甘林火；

【导师】 翁连进；

【作者基本信息】 华侨大学 ， 化学工程， 2004， 硕士

【摘要】 考察离子交换法从胱氨酸母液中提取L-精氨酸的过程中胱氨酸母液的脱盐、L-精氨酸在离子交换剂上的吸附及L-精氨酸的纯化精制三个主要过程。 首先，提出溶剂萃取与沉淀联合法脱氯盐的方法，考察了氯化钠和硫酸钠浓度、盐酸及硫酸浓度对萃取盐酸的影响。结果表明，氯化钠的存在和硫酸浓度的增大有利于提高盐酸与硫酸萃取分离系数，硫酸钠的存在使分离系数降低，盐酸浓度的增大使分离系数呈先增大后减小的趋势。含氯离子浓度高达3.2mol／L的胱氨酸母液经七级错流萃取后，其剩余氯离子浓度＜0.1mol／L，最终脱盐率＞98％。 其次，测定了25℃时阳离子交换树脂A、大孔阳离子交换树脂B和羧酸型阳离子交换纤维三种离子交换剂吸附L-精氨酸的吸附动力学曲线和吸附等温线，表明三者达到吸附平衡的时间分别为2小时、40分钟和30分钟，三者的最大平衡吸附量分别为115.94mg／g、136.49mg/g和91.76mg/g；考察了溶液pH值、温度、时间、氯化铵和氯化钠浓度对三种离子交换剂吸附L-精氨酸的影响，表明吸附的适宜pH均在7～8之间，氯化钠和氯化铵的存在均导致三者吸附L-精氨酸的吸附率迅速下降，温度对三者吸附L-精氨酸影响均不明显，吸附过程可在室温下进行。L-精氨酸在三种离子交换剂上的吸附行为均能用Langmuir方程较好地描述。综合比较最大平衡吸附量和平衡时间这两个重要指标，选用大孔阳离子交换树脂B作为离子交换法从胱氨酸母液中提取L-精氨酸工艺的离子交换剂，并考察其动态吸附与解吸曲线，L-精氨酸洗脱率可达99％。 次之，分别采用苯甲醛沉淀法和离子交换法对L-精氨酸粗提液进行纯化精制。考察了溶液pH值、苯甲醛与L-精氨酸摩尔比、氯化钠与氯化铵浓度、L-赖氨酸浓度、L-精氨酸初始浓度对苯甲醛沉淀L-精氨酸的影响，结果表明，沉淀反应的适宜pH值大于11，苯甲醛与L-精氨酸的适宜摩尔比为1.25，L-精氨酸适宜的初始浓度在15g/L以上，氯化钠的存在对沉淀率基本上没有影响，而氯化铵和L-赖氨酸的存在使沉淀率下降；同时测定了25℃时阴离子交换树脂A吸附L-赖氨酸的吸附等温线，表明其最大平衡吸附量为30mg/g，考察了溶液pH值、温度、氯离子浓度对阴离子交换树脂A吸附脱除L-赖氨酸的影响，结果显示从L-精氨酸和L-赖氨酸混合液中吸附分离出L-赖氨酸的适宜pH值为10.5±0.2，温度对L-赖氨酸吸附率影响不大，吸附过程可在室温下进行，氯离子的存在使L-赖氨酸的吸附率降低。 最后，将含氯化铵的胱氨酸母液经溶剂萃取与沉淀联合脱盐法除盐后，再经大孔阳离子交换树脂B柱初步分离出L-精氨酸，所得粗提液采用苯甲醛沉淀法对其进行纯化精制，L-精氨酸提取率可达80％。更多还原

【Abstract】 During the process of extracting L-Arginine from Lystine motherliquid by ion-exchange method, the desalting of Lystine motherliquid, adsorption of L-Arginine by ion exchanger and eluent’s fine purification were studied.First, the solvent extraction associating with precipitation method was suggested to desalt the Lystine motherliquid. The effects of concentrations of sodium chloride and sodium sulfate, the initial concentrations of hydrochloric acid and sulfuric acid on depickling were investigated. The results showed the separating coefficient between hydrochloric acid and sulfuric acid was increasing while increasing the concentrations of sodium chloride and sulfuric acid, the separating coefficient decreased under the existence of sodium sulfate, raising the concentration of hydrochloric acid caused that the separating coefficient was increasing before decreasing. After seven-stage cross current extraction, concentration of chloride ion of Lystine motherliquid varied from 3.2mol/L to 0. 1mol/L or less, the last desalting rate>98%.Second, adsorption kinetic curve and isotherm at 25 C of L-arginine on resin A, resin B and carboxylic ion exchange fiber were measured, the results showed that the equilibrium time of these three ion exchangers were 2 hours, 40 minutes and 30 minutes, respectively; and the maximal equilibrium adsorbances were 115.94, 136.49 and 91.76 mg/g, respectively; The influences of pH value, temperature, time, concentrations of sodium chloride and ammonia chloride on L-Arginine’s adsorption by these three ion exchangers were investigated, the results indicated that the proper pH value was between 7 and 8 during adsorbing, the adsorption rates of L-Arginine of these three ion exchangers were all decreasing rapidly under the existences of sodium chloride and ammonia chloride, temperature had little effect on adsorption of L-Arginine by these three ion exchangers, process could be operated at room temperature. Considering both of the maximal equilibrium adsorbance and equilibrium time, macropore cation exchange resin B was chose as the ion exchanger of the technology of separating L-Arginine from Lystine motherliquid by ion exchange method, its curves of adsorption and elution were studied, the result showed elution rate reached 99%.Third, the phenyl aldehyde precipitation method and ion-exchange method were utilized to refine the eluent. The effects of solution’s pH value, mol ratio between phenyl aldehyde and L-Arginine, concentrations of sodium chloride, ammonia chloride andL-Lystine, initial concentration of L-Arginine on precipitation rate of a -tolylene arginine were investigated, the results indicated that phenyl aldehyde precipitation method’s appropriate pH value was higher than 11, suitable mol ratio between phenyl aldehyde and L-Arginine was 1.25, initial concentration of L-Arginine was must higher than 15g/L, sodium chloride had little effect on precipitation rate, on the contrary, ammonia chloride and L-Lystine had great effect on it, both of them must be eliminated; At the same time, adsorption isotherm at 25 C of L-Lystine on anion exchange resin A was measured, the result showed that the maximal equilibrium adsorbance was 30mg/g, the influences of solution’s pH value, temperature, concentration of chloride ion on adsorption of L-Lystine by anion exchange resin A were also studied, the results indicated that appropriate operational pH value was 0.5 0.2, the effect of temperature on adsorption ratio was little, process could be operated at room temperature, the concentration of chloride ion must be eliminated.Finally, the Lystine motherliquid was desalted by the solvent extraction associating with precipitation method, then separated the L-Arginine roughly by adsorption on the ion exchange B column, the eluent was refined through the phenyl aldehyde precipitation method. The result showed that percentage extraction of L-Arginine reached 80%.更多还原