高岭石泥岩夹矸的焙烧相变特征和深加工应用

CHARACTERISTICS OF PHASE TRANSFORMATION DUE TO CALCINATION OF TONSTEIN AND ITS REFINED PROCESSING AND THE APPLICATION OF SYNTHETIC 4A MOLECULAR SIEVE IN PLASTICS INDUSTRY

通过热分析、X射线衍射分析对高岭石泥岩夹矸焙烧相变特征规律进行研究,阐述了深加工工艺方法,开重点研究了4A分子筛的合成工艺路线和在塑料中的应用性能。高岭石泥岩夹矸的脱羟温度大于600℃,说明其有序度高。高岭石在加热分解为偏高岭石的过程中衍射峰是逐步消失的。对高岭石泥岩深加工工艺包括超微细和改性(包覆、接枝、乳液聚合)、化学处理等方法,焙烧工艺非常关键,先超细再焙烧,可大大降低了能耗。由高岭石泥岩合成4A分子筛,因其具多孔结构和特殊的晶体形态,可显著提高重质碳酸钙在塑料中的分散性,具有固体分散剂的特征,故可用于塑料中以提高塑料产品性能。

In this paper, thermal and X-ray diffraction analyses were conducted of tonstein to characterize the phase transformation resultant from its calcination so as to reveal the laws that govern the change. Moreover, the refined processing technology and methods of tonstein were also expounded, and the focus is put on the technology and routes for the synthesis of 4A molecular sieve, its properties and its application in plastics industry. Results demonstrate that dehydroxylation of tonstein occurred at a temperature higher than 6001, which indicates a high degree of order for kaolinite, and it is also found that the diffraction peaks during the period when kaolin was calcined and decomposed into pianlinite disappeared step by step. The refined processing technology for tonstein includes superfine processing, property alteration (such as cladding, branching, emulsion polymerization, etc.), as well as chemical treatment methods. It is found in our research that the calcination technology is the key to the refined processing, and superfine processing must be followed by calcination in order for a remarkable reduction of the necessary energy consumption. The 4A molecular sieve synthesized from tonstein, due to its vesicular structure and special crystal morphology, can serve as a kind of solid dispersant and help to improve significantly the dispersiveness of heavy carbonate in plastics. As a result, the synthetic 4A molecular sieve can be extensively applied in plastics industry to improve the properties of plastic products.