| While microporous zeolites such as Y was playing a crucial role in FCC,much attention is draw to the mesoporous aluminosilicates.Unfortunately,mesoporous materials suffer from low hydrothermal stability,which hinders its industrial application in severe FCC process.To solve this problem,Our group reported that "MASTER-1" was obtained by introducing the primary and secondary structural units of the microporous molecular sieve into the pore wall of the MAs through the precursor assembly technology."MASTER-1" as the active component of "LPC-65" oil refining catalyst,was used in millions of tons of industrial catalytic production.However,there are defects in the synthesis process:low utilization rate of the template agent P123,large water consumption.To solve above problems the following studies were conducted in the paper:1.In this article,a novel strategy was developed by the introduction of Polypropylene glycol(PPG)to the P123 template system.In this process,part of PPG are "pushed" into the hydrophobic core of the micelles due to the repulsive effect.As the result of this,the rest of PPG molecules form a hydrophobic region accordingly.At the same time the P123 single molecules will close to the hydrophobic region that formed micelles by PPG molecules.From the results of BET and XRD studies,the sample has a typical p6mm mesoporous structure.The product obtained from the scale-up synthesis has"worm-like" mesoporous structure.2.High-concentration P123 template(0.16 mol/L)is expected to be the ideal system to improve its utilization efficiency.However,the negative effect of this system is the agglomeration of micelles,which will result in the decreased utilization rate of P123.In this composite system,PPG molecules are"pushed" into the hydrophobic core of the micelles due to the repulsive effect.its inherent hydrophilic segment will increase the hydrophilicity of the micelle and prevent micelles’ agglomeration.At the same time,the introduction of PPG increased the volume of the hydrophobic and hydrophilic segments of the micelles,which ultimately led to the bbigger pore size and the thicher wall thickness of the MAs.3.As a polar solvent,glycine is reasonably deduced to form a composite micelle through interaction between between glycine and PPO blocks.The utilization rate and water consumption of sample P123 were 0.85 g P123/g zeolite and 17.8 g H2O/g zeolite,respectively.Compared to the conventional method,the utilization rate of P123 is increased by 30.6%,the water consumption is reduced by 57.6%,and the synthesis cost reduced by 20.2%.From the results of BET,the specific surface area and total pore volume are 721 m2/g and 0.79 cm2/g.On the basis of above investigations,P123/glycine composite template system was used for pilot scale-up synthesis study(10 times magnification).The product obtained from the scale-up synthesis has "worm-like" mesoporous structure.In addition,The amplifying product has good performance comparable to that of laboratory samples.The results shed a light on the industrial production of MAs.Utilization efficiency of both P123 and water were improved greatly by using Mother liquor recycling(MLR)method.Glycine acting as the inhibitors of micelle agglomeration is added to every cycle.As the consequence of this,Si,Al and template can be recycled in the mother liquor process,and the utilization efficiency of the template water are 0.80 g zeolite/g P123 the 16.8 g H2O/g zeolite respectively.To sum up,the ues of synthesis of MAs by using composite templates,which explores the induction of PPG,the auxiliary of PPG and the composite system of glycine.And explores effects on the mechanism and properties parameters of synthetic process of Mas.Eventually,the Mas has a high hydrothermal stability.What is more,there are lower water consumption and higher utilization efficiency of template compare to conventional product.As the consequence of this,the synthetic cost is rapily reduced.Successful synthesis of MAs has laid a solid foundation for industrial application. |
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