【作者】 王纯；

【导师】 仲剑初；

【作者基本信息】 大连理工大学 ， 化学工艺， 2010， 硕士

【摘要】 过硼酸钙与过氧化镁都是重要的碱土金属过氧化物。其中过硼酸钙是一种高附加值的精细硼化学品,可作为油墨、颜料的催干剂和聚烯烃催化剂的减活剂。虽然国外已开展了这方面的研究,但是国内尚无相关的生产技术。因此,开发过硼酸钙合成的新工艺,可填补国内在这一领域的空白。过氧化镁不仅具有较强的氧化作用,而且具有一定的碱性和防腐作用,因此是一种用途十分广泛的无机过氧化物,可用于化妆品,医药,环境保护等方面。本文研究的工作涉及两个部分：过硼酸钙的合成和过氧化镁的合成。过硼酸钙的制备工艺是先以硼砂(或硼酸)和氢氧化钙为原料合成偏硼酸钙,然后自然风干的偏硼酸钙与30%的过氧化氢在稳定剂存在下进行液固相反应,经过滤及干燥制备出过硼酸钙。实验考察了合成偏硼酸钙的原料、合成偏硼酸钙的配料硼钙比、反应温度、反应时间、液固比及稳定剂的种类等因素对过硼酸钙合成、得率和活性氧含量的影响。研究结果表明用硼砂和氢氧化钙为原料合成的偏硼酸钙,其晶体的表面形貌和结构更有利于制备过硼酸钙；合成偏硼酸钙的配料硼钙比对过硼酸钙活性氧含量也有影响,配料硼钙比m(B203)：m(CaO)为2.2：1时获得的过硼酸钙活性氧含量最高。过硼酸钙合成的其他适宜工艺条件为：反应温度60℃；反应时间40min；液固比为3.5：1(mL／g)；添加复合稳定剂Q。在上述条件下,制备的过硼酸钙组成为：B2O327～29%,CaO 22-24%,活性氧含量≥13.5%, Fe≤0.04%。在上述试验因素考察的基础上,为探索工业生产实施的可行性,对过硼酸钙的合成反应进行了循环实验研究；母液返回循环的试验表明：随着循环次数的增加,产品的活性氧含量逐渐减少,第九次循环的活性氧含量小于16%。过硼酸钙的热稳定性研究表明：在100℃的环境中放置1小时,过硼酸钙活性氧损失严重；在80℃环境中放置1小时,活性氧很稳定,没有损失,但放置2小时后其活性氧含量减少。过氧化镁的制备工艺是以碱式碳酸镁为原料,首先经过煅烧制备出活性较高的氧化镁,活性氧化镁再与30%的过氧化氢溶液进行液固相反应,经过滤及干燥制备出过氧化镁产品。实验考察了碱式碳酸镁的煅烧时间、煅烧温度,氧化镁中氧化钙的含量对过氧化镁的合成、得率和活性氧含量的影响。研究结果表明,碱式碳酸镁的煅烧时间和煅烧温度对合成过氧化镁的活性氧含量有较大影响,最佳煅烧时间为2h,煅烧温度为650℃。活性氧含量与得率随氧化镁中氧化钙的含量的增加而降低。通过对反应液固比、反应温度、反应时间及稳定剂因素进行考察,确定了适宜的工艺条件：在室温下,采用4：1(mL／g)的液固比,反应10min,获得的过氧化镁含Mg 31-32%,活性氧含量大于15%。过氧化镁的热稳定性分析结果表明：将过氧化镁在100℃下放置1h,活性氧含量损失1.17%,但可以提高过氧化镁的表观活性氧含量。更多还原

【Abstract】 Calcium perborate and magnesium peroxide are alkaline earth peroxide. Calcium perborate is a kind of fine boron chemicals with high additional value; it can be used as driers for ink or pigment, and deactivator of polyolefin catalyst. Although a few researches on alkaline earth perborate have been reported, there is no research in this respect at home.The study on the synthesis process of calcium perborate can remedy the shortage studied in this respect at present in our country. Magnesium peroxide not only has strong oxidation, but also has basic property and preservation; Therefore, it is one of the most versatile inorganic peroxide used in the areas of cosmetic, medicine and environmental protection and so on.The research work of this dissertation has two parts:the synthesis of calcium perborate and the preparation of magnesium peroxide.The preparation of calcium perborate can be divided into two steps:calcium metaborate was first prepared from borax (or boric acid) and calcium hydroxide, and then the air dried calcium metaborate was employed to react with 30% hydrogen peroxide in the presence of stabilizer, and the resultant mixture was filtrated to obtain calcium perborate. The effects of raw materials used for preparing calcium metaborate, the ratio of reaction raw materials employed for preparing calcium metaborate, reaction temperature, reaction time, liquid-to-solid ratio and kinds of stabilizer on the synthesis, yield and active O of calcium perborate was investigated, respectively. The results show that the surface morphology and structure of calcium metaborate prepared by borax is more suitable for manufacturing calcium perborate.The material ratio for preparing calcium metaborate also had an influence on active O of calcium perborate, the content of active O in calcium perborate is maximum when m (B2O3)/m (CaO) of reactive raw materials is 2.2:1. Based on experiments, the other suitable processing parameters were also obtained, i.e. reaction temperature and time,60℃and 40min; liquid-to-solid ratio,3.5:1(mL/g); adding composite stabilizers Q. The mass fractions of B2O3 and CaO in the product have reached 27-29%,22-24%, the mass fraction of active oxygen is above 13.5% and that of Fe less than 0.04%, respectively. According to the above mentioned investigation, the circulation experiments on the synthesis of calcium perborate with returning mother liquor were carried out in order to probe into industry operation. The experiment results demonstrate that the content of active O in calcium perborate would be decreased with the increases of the cycle number and the content of active O in calcium perborate is less than 16% at cycle 9. The researches on thermal stability of calcium perborate indicated that the loss of active oxygen was a serious problem when calcium perborate was stood at 100℃for an hour, and the content of active O was stable when it was stood at 80℃for an hour, but the content of active O was decreased when the product was stood at 80℃for two hour.Magnesium peroxide was prepared by the reaction of high active magnesia calcined from basic magnesium carbonate with 30% hydrogen peroxide. The effects of the calcination time and temperature of basic magnesium carbonate, content of calcium oxide in magnesium oxide on the synthesis, yield and active O of magnesium peroxide were investigated, resectively. The results indicated that the calcination time and temperature of basic magnesium carbonate play an important role in the active oxygen conten of magnesium peroxide, and the suitable calcination time and temperature are 2h and 650℃, respectively. The content of active O and yield for magnesium peroxide would be decreased with increaseing the content of impurity calcium oxide in the magnesium oxide. The effects of reaction liquid-to-solid ratio, reaction temperature and reaction time on the synthesis of magnesium peroxide were investigated, and suitable processing parameters were obtained, i.e. room temperature, liquid-to-solid ratio 4(mL):1(g), reaction time 10min. The mass fraction of Mg in the product have reached 31-32%, the mass fraction of active oxygen is above 15% under the suitable conditions. The researches on the thermal stability of magnesium peroxide showed that the loss of active oxygen is 1.17% when magnesium peroxide was stood at 100℃for an hour, while the fraction of apparent active oxygen in magnesium peroxide was increased.更多还原