Research On New Process Of Oxidation Refining Of Montan Wax And Its New Method Of Quality Evaluation

It has become a basic trend in the development of the industry that the oxidation refining process of montan wax being transformed to low-chromium and chromium-free.Exploring a more excellent oxidation refining process has always been a hot topic in the field,because this is crucial for the development of high-end products and even the overall value-added.Moreover,there has not been a relatively perfect methodological system about the quality evaluation on montan wax for a long time,especially the lack of a quality standard of comprehensive exterior color quality and internal material basis.But it is indispensable for the montan wax product classification,quality control,adulteration identification and origin attribution.Based on this,a series of related work of this thesis has been carried out,striving to break through the technical bottleneck of the original and provide a certain theoretical basis and practical basis for the process transformation and quality standard establishment of montan wax.The details and results were as follows:1.The backgrounds of lignite,montan wax,oxidation refining process,environmental oxidants,color space technology and fingerprint technology has been summarized through a lot of literature researches,on the basis of which the main research topics,research significance,technical route and the expected goals have then been summarized.2.The oxidation bleaching effects of the chromium-free oxidant system(P,Pa,P-Pa,Pa-P)and the low-chrome oxidant system(Pa-P-Cr6+,Cr6+-Pa-P)have been systematically studied,and it's shown that the Pa-P method and the Cr6+-Pa-P method were relatively good,then,related optimization experiments were done on this basis.Optimized according to the response surface methodology,the best bleaching conditions of Pa-P method were:Pa:ESRRMW-20:1,P:ESRRMW-36.72:1,t-80min,T-118.49?,and under this condition,the L value of the product was 62.02.In addition,according to preliminary simple optimization,the better whiteness process conditions of Cr6+-Pa-P method were:Na2Cr2O7·2H2O:ESRRMW-1.96:1,and the rest parameters remain consistent with the best value of Pa-P method,.Under this condition,the L value of the product was 62.09.However,judging from the product nature,the latter was obviously better than the former,and the latter was close to the product' nature of Cr6+ method.3.CIE Lab color mode was used to characterize the montan wax exterior colors digitally.Based on its feasibility and reliability,a color quality evaluation model of montan wax(y= 0.9*L-| 0.02*a |-| 0.08*b |)was established,and the composite scores of refined montan wax products from Zhaotong,E'shan,Xundian and Baoqing refined by Cr6+ method were obtained as follows:80.5,80.7,72.3,80.7.It was entirely consistent with the human visual perception trend.This method has made up for the language description failing to quantify the color differences and it has provided a strong reference for the color quality grading of montan wax.4.All the components of refined montan wax products from Zhaotong,E'shan,Xundian and Baoqing refined by Pa-P method,Cr6+ method and Cr6+-Pa-P method were characterized by GC.It's indicated that the compositions of the latter two were almost the same,but there were some differences with the former one.Meanwhile,there were similar features among the chemical compositions of the refined montan wax products in the four regions.All components and local components of representative refined montan wax' products refined by Pa-P method and Cr6+ method were qualitative analyzed by using GC-MS.It's indicated that the main components of the two were C15-C30 acids,and other minor components were mainly C20-C30 alcohols and C20-C30 hydrocarbons.Besides,acids of the latter were more than the former,and alcohols of the former were more than the latter,and hydrocarbons of the two were almost the same.The result was consistent with basic principle of the material change of oxidation refining process.It's revealed that the root cause for the product quality of the former not as good as the latter lies in its relatively shallow degree of oxidation.5.On the basis of investigation in the methodology,GC fingerprints of montan wax products in the four regions were established and the compositions of their internal features were reflected by the relative retention time and relative peak area values.It's shown that there was a high degree of similarity between the fingerprints while certain differences also exist.And it's also deep discussed on aspects such as process controlling,adulteration identification and origin attributions,which showed that there were pretty high practical value in these aspects.In addition,compared with the similar products of German montan wax,Chinese products have achieved a comparable level.