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多元萃取体系提取林可霉素的热力学研究

Study on Thermodynamics in Multi-Extraction System of Lincomycin

【作者】 李瑸

【导师】 吴兆亮;

【作者基本信息】 河北工业大学 , 化学工艺, 2004, 硕士

【摘要】 林可霉素是一种高效广谱抗生素,对组织和细胞的穿透力强,临床上常用于骨髓炎的治疗。目前,在工业上萃取法提取发酵液中的林可霉素因其成本低和操作简单而受到广泛应用。本文针对林可霉素发酵体系的特点提出了林可霉素的测定方法,比较了不同类型溶剂对林可霉素的萃取性能,提出了以多元萃取剂提取林可霉素的方法,寻找到了适合该体系的二元萃取剂,并对萃取剂进行了优化和工艺研究,计算了多元萃取体系的热力学函数。将UNIFAC基团贡献法应用于林可霉素多元萃取体系——液液大分子体系,根据所得相干衡常数对体系中缺少的基团交互作用参数进行了回归,绘制了多元萃取体系相图。 1.林可霉素的测定方法 研究了旋光法测定溶液中林可霉素的影响因素,并以氯化钯为显色剂,建立了紫外分光光度法测定发酵液中林可霉素含量的方法。其操作条件为:最佳测定波长为380nm,络合物稳定时间为30min,测定0.5ml发酵液所需显色剂的最佳用量为0.5ml,显色剂浓度为0.02mol/L,林可霉素效价浓度在20u/ml~300u/ml范围内吸光度与效价浓度有线性关系。 2.二元萃取剂提取林可霉素 以醇类萃取剂B—S组成的二元萃取体系对林可霉素的分配系数明显高于其它溶剂体系,在pH为10.5时,其分配系数是正丁醇的2倍,且溶剂在水中的溶解度比正丁醇下降了2.5倍。萃取剂体系中萃取剂B的适宜体积分数为60%—80%,且在该浓度范围内有协萃效应,最大协萃系数1.28。同时,该萃取剂还具有理化性质稳定、毒性较小、挥发度较低且工业中易得的特点。 3.多元萃取体系的工艺研究 以萃取剂B—S组成的二元萃取剂对林可霉素最佳操作条件:料液pH值10.6,相比(O/A)2:1,萃取剂B体积分数65%,萃取温度35℃。反萃水pH值小于2.0即可顺利实现反萃取,反萃率可达95%以上。相同条件下,萃取发酵液中林可霉素,其萃取率与水溶液相比仅下降2%左右。萃取过程的溶剂化系数分别为1.79、0.89(萃取剂B,S),萃取平衡常数为5.194,ΔH_m为12.96kJ/mol,ΔG_m为—13.306kJ/mol,ΔS_m为85.24kJ/mol。 4.UNIFAC基团贡献法在体系中的应用 填补了一些UNIFAC—r~∞参数数据,共回归了9个亚基团的44个基团交互作用参数。根据文献数据以及回归得到的参数,用UNIFAC法计算了林可霉素的相平衡常数,与实验所得数据误差相比除个别数据外部在30%以内,基本满足了工程计算的需要。用UNIFAC法计算的其他体系的相平衡常数与实验数据相比,也有较好的精度,误差也均在30%以内。 5.多组分相图绘制绘制了在不同温度下,萃取相浓度和萃余相浓度与萃取剂浓度之间关系的相图。在相图中发现随着萃取剂B浓度增加,平衡线的斜率逐渐减小,即萃取相中林可霉素浓度与萃余相中林可霉素浓度比值逐渐增加,萃取率逐渐上升。

【Abstract】 Lincomycin, which is a type of high active and broad spectrum antibiobtic, has been used for the clinical treatment of osteomyelitis for its penetrability in tissues and cells. Presently, extraction is an accepted method in the extracting process of lincomycin from fermented broth in industry for its low cost and simpleness operation. In this paper, according to the properties of lincomycin, method of measurement of lincomycin concentration in broth was constructed, extracting capability of different solvents was researched, the method of extracting lincomycin by multi-extractant was put forward, a new binary-extractant fitting for extracting lincomcy was found and optimized, extracting technology was studied, and thermodynamics parameters was calculated. UNIFAC group-contribution method was applied in lincomycin extraction system, macro-molecule system, and group interaction parameters was complemented according to experimental data. Phase graph was drawed for multi-extraction system.1.Method of measurement of lincomycin concentration. Effect on rotation-measurement of lincomycin concentration was studied. And the method of measurement of lincomycin concentration in fermented broth by spectrophotometry was established, which was used palladium chloride as color reagent. Optimum measured wavelength is 380nm, reaction time is 30min, and dosage of color reagent is 0.5ml which concentration is 0.02mol/l measuring 0.5ml fermented broth. In the range of 20-300u/ml, absorbency and lincomycin concentration has linear relation.2.Extraction of lincomycin by binary-extractant. Extractant B-S, mellow solvent, has higher extraction ability than others. Distribution coefficient of lincomycin in it is twice times as much as it in n-butanol, and solubility of it is twice and a half times as low as n-butanol’s. Optimum volume fraction of extractant B in binary-extractant is 60%-80%, and the highest cooperate coefficient is 1.28, which exists in this range. Besides that, this binary-extractant also has characters of stabilization, low toxicity, low volatilization and facile in industry.3.Optimization of extraction technology. Optimum conditions of extraction of lincomycinby binary-extractant is: aqueous pH 10.6, ratio of phase (O/A) 2:1, volume fraction of extractant B 65%, temperature 35℃. Stripping process can be achieved whose pH of stripping water is lower than 2.0, and stripping extraction is higher than 95%. In the same condition, extraction of extracting lincomycin in fermented broth decreases as little as 2% contrasting with it in aqueous solution. Coefficients of solvation are 1.79 and 0.89 (for extractant B,S), and constant of extraction equilibrium is 5.194, △Hm is 12.96kJ/mol, △Gmis - 13.306kJ/mol, △Sm is 85.24kJ/mol.4.Application of UNIFAC group-contribution method 44 interaction group-parameters of 9 sub - groups was fitted for complementing the parameters of UNIFAC--r∞. Equilibrium coefficient of lincomycin was calculated by UNIFAC method according to the literature data and fitted data. Error of value is less than 30% compared with experimental ones expect one or two, which can meet the needs of the engineering calculation. The method was even used for reckoning other systems’ equilibrium coefficient. The precision was satisfied, and error is less than 30% , too.5.Painting of phase graph for multi-component. Phase graphs were drawed which described the relation between concentration of lincomycin in extractant and raffinate and volume of extractant in different temperatures. In phase graph, some rules is learned, which slope of equilibrium of curves is decrease with the increase of volume fraction of extractant B, that is the ratio of concentration of lincomycin in extractant and in raffinate gradually increasing, and extraction was so.

  • 【分类号】TQ465
  • 【被引频次】5
  • 【下载频次】328
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