Controlled Synthesis And Application Of Magnesium Oxate

Magnesium oxyacid salt resources are abundant and widely distributed in China.The efficient utilization method of magnesium resources is to transform them into inorganic functional materials such as magnesium carbonate and magnesium silicate which have industrial application value and are diversified in size,phase state as well as morphology.Among them,amorphous magnesium carbonate,as a precursor of biomineralization and magnesium functional material,is widely used in the fields of medicine,rubber,plastics and food additives.Magnesium silicate crystal material is a kind of stable performance,economic and environmental protection material,and has a high specific surface area and abundant pore structure,so it has a great potential application in the field of environmental treatment.Therefore,it is a great academic significance and industrial application value to study the synthesis method of relatively simple magnesium oxyacid salt and explore the formation mechanism and application of its specific form.In order to better understand the growth process of magnesium oxyacid salt under special conditions,the specific morphology and crystal form of functional materials were obtained.This paper respectively by nano amorphous magnesium carbonate and petals shape morphology of crystal magnesium silicate as the research target,it was realized that the nano amorphous magnesium carbonate(50-110nm)the controllable synthesis and crystal transformation as well as its application in high density polyethylene by polyamide amine(PAMAM).At the same time,it was explored that the synthesized under the condition of moderate magnesium silicate crystals,its surface modification and thiol nano Fe S load.This paper studied the basic application value of functionalized magnesium silicate for the adsorption and degradation of methylene blue.The specific results are as follows:1.In this paper,the experimental conditions of G0.5 PAMAM water system were explored by one-step precipitation method to realize the controlled synthesis of amorphous magnesium carbonate.The stability of amorphous magnesium carbonate was enhanced by the molecular cavity and electrostatic interaction of G0.5PAMAM.When the concentration of G0.5PAMAM was 3000mg/L,the stability time of amorphous magnesium carbonate was the best(1870s),which was 3 times that of water system.At the same time,temperature is an important factor affecting stability,the higher the temperature,the more conducive to the conversion of amorphous magnesium carbonate to magnesium carbonate.The application results of polyethylene showed that the tensile strength of polyethylene increased by 5.02% when the addition amount was 2wt%.Tensile strain increased from 756.87% to 805.24%.2.Under normal pressure conditions,it was explored the influence of factors such as p H value and raw material ratio on the crystallization and morphology of magnesium silicate under mild temperature conditions(20-80℃).The results showed that the crystallinity of magnesium carbonate increased from 12.65% to 66.14% at the temperature of 20-80℃,which indicated that the temperature is the main factor affecting the crystallization of magnesium silicate,and the higher the temperature is,the more beneficial to the formation of crystal phase of magnesium silicate.3.The surface of petal-like crystal magnesium silicate synthesized at 80℃ was modified by sulfhydryl group,supported by nano-Fe S and adsorbed by methylene blue.The results showed that the surface of magnesium silicate supported Fe S had good dispersion and uniform particle size.When p H=10,the maximum adsorption capacity of methylene blue by magnesium silicate crystal was 304.7mg/g.The surface loaded nano-Fe S magnesium silicate crystals showed good removal effect on methylene blue in the range of p H4-10,and the maximum removal capacity was 318.3mg/g.