【作者】 高峰；

【导师】 潘鹤林； 温俨；

【作者基本信息】 华东理工大学 ， 化学工程， 2011， 硕士

【摘要】 在生产AKD(Alkyl Ketene Dimer,烷基烯酮二聚体)中性造纸施胶剂时,所使用的AKD蜡由国外进口产品改为国内生产产品时会有很高的经济效益。考虑到进口AKD蜡所使用的原料与国内的不同以及国产AKD蜡在纯度、稳定性以及施胶效果较国外的产品稍有不足。通过对AKD乳液的乳化过程进行分析和优化,在AKD蜡的乳化加工过程中通过配方优化以及工艺调整提高AKD乳液的稳定性、活性以及减少沉积物的产生,从而最大化的提高国产AKD乳液的使用价值。通过对进口及国产AKD蜡的分析发现,不同AKD蜡在碳链结构上存在差别,对于碳链较长的国产AKD蜡在加入较多的淀粉乳化剂时有助于提高其乳液粒径分布。即在不使用进口AKD的情况下,使用国内厂家生产的AKD原料,可以通过适当增加乳化剂的用量得到粒径分布较好的乳液,有助于乳液稳定性的提高及纸机应用。在对AKD进行乳化时需要针对不同的AKD蜡通过实验室确定其乳化温度。在使用国内厂家生产的AKD原料,在稳定性稍差时,可以在加工过程中的熔融、预混、均化等阶段适当提高温度,可以制得粒径分布较好的乳液产品,可以明显提高乳液的稳定性。AKD施胶剂中决定施胶效果好坏的关键指标是AKD施胶剂的活性含量。由于加工工艺以及设备、原料等差别,进口的AKD蜡活性含量较高。而AKD蜡活性的损失的主要途径是水解,随着温度升高,AKD蜡的水解程度和水解速率也随之升高。在使用国产AKD蜡时通过对温度的调整以及加工工艺中抑制水解的发生来减少活性损失,通过这些措施获得了较好的效果。在将温度设定为70℃以及对工艺进行优化后,使用国产AKD蜡生产得到的乳液完全符合要求,施胶效果达到采用进口AKD蜡制作的施胶剂同等水平。在使用国产AKD蜡作为原料生产AKD施胶剂时,通过对配方、工艺的调整,获得粒径分布较小的乳液,从而在纸机应用时减少沉积物的产生。更多还原

【Abstract】 In the AKD neutral sizing manufacture industry, there will be much economic profit when shift the AKD wax from import to local supplier. However consider there are some difference between import AKD wax with local AKD wax, such as the raw materials of AKD wax, a little bit poor in impurity, stability and sizing performance in local AKD wax. We focus on analyze and optimize the process of AKD emulsion manufacture to get the good paper machine application results with local AKD wax by optimize the AKD emulsion formulation and process, try to improve the performance of local AKD wax sizing emulsion by enhance the emulsion stability, assay and decrease the deposit in emulsion.We have analyzed the import and local AKD wax, the results show there are difference in import and local AKD wax in molecular carbon chain. for the local AKD wax, the carbon chain is much longer than import’s, and the more the emulsification agent has been added to AKD emulsion with local AKD, the more good particle size distribution emulsion you will get. That is to say, even with the local AKD wax, we can get the good particle size distribution emulsion with good stability and good paper machine application results.Before emulsify the AKD wax, a lab testing should be carry out to determine its the melting point according to different sourcing AKD wax. When making emulsion with local AKD with poor stability, we can increase the temperature during the melting, pre-mixing and homogenization steps to achieve good emulsification results to get good particle size distribution and stabile products.The key parameter in AKD emulsion relate to sizing performance is AKD assay. Due to the difference in manufacture process, equipment and raw materials, the import AKD wax has much higher assay. The main AKD assay loss is hydrolyzation, the hydrolyzation degree and speed depend on the temperature, the much higher temperature, the more rapid hydrolyze reaction and higher degree in hydrolyzation. The assay loss can be decreased during the AKD emulsification if control the temperature to a proper value and control the steps which there is hydrolyzation reaction. When use local AKD, if we control the emulsification temperature to 70℃and optimize the manufacture process, good AKD emulsion can be got and all characteristic meet specification requirement, the sizing performance can be same level with the emulsion with import AKD wax.The good particle size distribution emulsion can be got when using the local AKD wax by formulation and process modification, and then can reduce the deposit issue in paper application.更多还原