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绿色阻垢剂聚环氧琥珀酸的合成及阻垢机理研究
The Study of Synthesis and Scale Inhibition Mechanics of Contamination Free Scale Inhibitor Polyepoxysuccinic Acid
【作者】 高书峰;
【导师】 张爱民;
【作者基本信息】 四川大学 , 材料学, 2007, 硕士
【摘要】 聚环氧琥珀酸是上世纪90年代开发出来的一种环保型阻垢剂,它具有优良的阻垢性能,且无磷、非氮、可生物降解性好,是现在阻垢剂的更新换代产品。本文以顺丁烯二酸酐为原料,通过环氧化和开环聚合的方法合成了一种聚环氧琥珀酸(PESA)。整个合成过程分两步进行研究:环氧琥珀酸(ESA)的合成和聚环氧琥珀酸的合成。在第一步反应中,利用紫外—可见分光光度法测得了产物中未反应的马来酸和副产物酒石酸的含量,间接求出了环氧琥珀酸的收率;通过实验设计系统研究了各工艺参数对环氧琥珀酸收率的影响,得到了优化的环氧琥珀酸合成工艺。在此基础上,加入引发剂使ESA聚合得到了PESA,同样进行了系统的实验,以产物的最终阻垢率为考察目标,研究了影响因素与产物阻垢性能之间的关系,最终得到了较好的聚环氧琥珀酸的合成工艺。利用红外光谱表征了环氧琥珀酸和聚环氧琥珀酸的分子结构,发现环氧琥珀酸分子中含有特征基团环氧基,而在聚环氧琥珀酸的红外谱图中,环氧基的特征吸收峰消失,出现了醚键的特征吸收峰,说明环氧琥珀酸在引发剂的作用下发生了开环聚合。用核磁共振碳谱验证了所得产物确实具有与设计的聚环氧琥珀酸相同的分子结构。采用静态阻垢法考察了PESA阻碳酸钙垢的性能,结果表明,PESA具有良好的阻垢性能,适用于高碱高固水系。通过X射线衍射和扫描电镜等分析手段研究了聚环氧琥珀酸加入前后碳酸钙垢晶型的变化,发现PESA的加入使碳酸钙的晶格发生了畸变,由原来的方解石晶型转变为文石和球霰石,碳酸钙垢的形态由致密的硬垢转变为疏松的软垢,易于被流水冲去;并研究了加入PESA前后碳酸钙成垢诱导期的变化,发现PESA可以增加碳酸钙成垢的位垒,使钙离子能较长时间的稳定在水中而不析出。在此基础上探讨了聚环氧琥珀酸的阻碳酸钙垢的机理。
【Abstract】 Polyepoxysuccinic acid(PESA) is a kind of contamination free scale inhibitor,which was exploited in the 90’s, last century. It is wildly used as a new product ofscale inhibitor at present for its excellent scale inhibition, biodegradability andunique molecular structure having no hetero-atoms such as nitrogen and phosphorus.In this paper, PESA was synthesized through epcxidation and epoxy breakingpolymerization from the raw material maleic anhydride, which included two steps:The synthesis of epoxysuccinic acid (ESA) and the polymerization of ESA. Duringthe first step, the content of tartaric acid and maleic acid unreacted were determinedby spectrophotometer, and then the yield of epoxysuccinic acid was calculated. Theinfluence of technological parameter to the yield of ESA was investigated throughexperimental design, and the optimized synthetically technology of ESA wasachieved. In the second step, ESA was polymerized using initiator. Systematicalexperiments were carried out to investigate the influence of technological parameterto scale inhibition of PESA. A preferable polymerization technology of PESA wasachieved.The molecular structure of ESA and PESA was characterized by infra-redspectrometry. It was revealed that there was epoxy in ESA molecules. However thewave crest of epoxy disappeared in IR spectrum of PESA and was taken the place ofthe wave crest of ether link. It showed that ESA polymerized though epoxy breaking.The product was proved to have the same molecular structure with PESA by13C-NMR.The property of CaCO3 inhibition of PESA was investigated by static tests whichrevealed that PESA has high scale inhibition performance, and is suitable for high pH value and hard water.Calcium carbonate crystal parameter and morphology was investigated by X-raydiffraction (XRD) and Scanning Electron Microscopy (SEM). It was revealed thatwhen PESA was added, the crystal of calcium carbonate was deformed from calciteto aragonite and vaterite, and the morphology of the scale of calcium carbonate wasturned from compact hard scale to loose soft scale, which could be easily washed offby water scouring. The effect of PESA to the induction period of calcium carbonatescaling was also studied, it was revealed that PESA could increase the potentialbarrier of calcium carbonate scaling to hold the Ca2+ in the water longer time, basedon which the scale inhibition mechanism of PESA was discussed.
【Key words】 Polyepoxysuccinic acid; Synthesis; Scale inhibition; Scale inhibition mechanism;
- 【网络出版投稿人】 四川大学 【网络出版年期】2008年 05期
- 【分类号】TQ317
- 【被引频次】8
- 【下载频次】768