羟乙膦酸钠合成工艺的研究

论文编号:HG196  论文字数:8890,页数:20

 摘 要：本论文是关于羟乙膦酸钠合成工艺的研究。以往的合成方法多采用两步法制备，即先制得羟乙膦酸，然后用冰醋酸重结晶，最后成钠盐。现将羟乙膦酸钠的合成方法由两步法改进为羟乙膦酸粗品不经重结晶而直接成盐。加一倍水稀释后，再加40%的氢氧化钠中和至pH值为4.5，最后加三倍乙醇沉淀得到羟乙膦酸钠的方法。研究了原料配比、反应温度、水用量和乙醇用量对产品质量和收率的影响。通过单因素法得出的最佳反应条件为：三氯化磷和醋酸摩尔配比为1：3、反应温度为110℃、水用量为1当量和乙醇用量为3当量。此方法不仅省略了羟乙膦酸重结晶步骤，而且简化了生产工艺，操作简单。提高了产品质量和收率，节约了设备和原料投资。
关键词：羟乙膦酸钠；羟乙膦酸；产品质量和收率

Abstract: This article is about study on synthesis of sodium etidronate . In the past , two-steps method was used. First , 1 - hydroxyethylidene -1,1- diphosphonic acid was preparated , then turned to sodium salt after recrystallizating with glacial acetic acid . And now the two-steps method of Synthesis of Sodium Etidronate is improved that the 1 - hydroxyethylidene -1,1- diphosphonic acid without recrystallizating but directly turned into salt . Water was added for diluting firstly, then 40% of sodium hydroxide was added for raising the pH value to 4.5 , at last three times’ volume of ethanol was plused to precipitate and get the Sodium Etidronate . It investigated the quality of products and yield by using different ratio of raw materials , different reaction temperature , different water usage and different volume of ethanol . Using single factor test , the result enunciate that the most suitable and proper reaction conditions is that: acetic acid and phosphorus trichloride’s molar ratio is 1:3 , the reaction temperature is 110℃ , the water usage is one time and the volume of ethanol is three times . This method not only omitted the step of recrystallization of 1 - hydroxyethylidene -1,1- diphosphonic acid, but also simplified the production process and operation . The quality of products and yield were improved , and equipment and raw materials investment were saved .
Keywords：Sodium Etidronate ; 1-hydroxy-ethylene-1,1diphosporic acid ; the quality of products and yield
 
目  录
中文摘要…………………………………………………………………………………………I
英文摘要 ………………………………………………………………………………………II
目录  …………………………………………………………………………………………III
目录   …………………………………………………………………………………………Ⅳ
1．绪论 …………………………………………………………………………………………1
    1.1 前言  …………………………………………………………………………………1
 1.2 研究现状  ……………………………………………………………………………1
 1.2.1 合成工艺（一） ……………………………………………………………3
 1.2.2 合成工艺（二） ……………………………………………………………3
 1.2.3 合成工艺（三） ……………………………………………………………3
 1.2.4 合成工艺（四） ……………………………………………………………3
2.实验部分  ……………………………………………………………………………………5
 2.1 实验仪器与试剂  ……………………………………………………………………5
 2.2 羟乙磷酸的合成………………………………………………………………………6
 2.3 羟乙磷酸钠的制备  …………………………………………………………………6
 2.4 反应条件的优化  ……………………………………………………………………7
 2.5 乙酸和乙醇的回收 ………………………………………………………………… 7
3.  结果与讨论 ……………………………………………………………………………… 8
 3.1 羟乙磷酸的合成 ……………………………………………………………………… 8
 3.2 羟乙磷酸钠的制备  ……………………………………………………………………8
 3.3 反应条件的优化 ……………………………………………………………………… 10
 3.3.1 原料配比的影响 ………………………………………………………………… 10
 3.3.2 反应温度的影响 ………………………………………………………………… 10
 3.3.3 水用量的影响 …………………………………………………………………… 11
 3.3.4 乙醇用量的影响   ……………………………………………………………… 12
3.4 乙酸和乙醇的回收 ……………………………………………………………………… 13

4.  总结与展望 ……………………………………………………………………………… 14
致谢 …………………………………………………………………………………………… 15
参考文献 ……………………………………………………………………………………… 16