Introduction of Anionic Surfactants to Copolymer Micelles: A Key to Improving Utilization Efficiency of P123 in Synthesis of Mesoporous Aluminosilicates

Abstract

Mesoporous aluminosilicates (MAs) with high hydrothermal stability by assembly of zeolite Y precursors have been emerging as the most promising materials for cracking heavy oil molecules. A means to improve utilization efficiency of organic surfactants is of vital importance in synthesis of MAs. In this work, this goal was achieved by the introduction of ionic surfactant micelles in low concentration of copolymer. It is found that the strong interactions between the hydrophobic chain of sodium dodecyl sulfate (SDS) and poly(propylene oxide) (PPO) units of P123 lead to the formation of mixed micelles even at low concentration of P123. The self-aggregation of SDS molecules could induced the formation of mixed micelles with a core consisting of SDS micelles with PPO units and a corona of poly(ethylene oxide) (PEO) units. The mixed surfactants (SDS/P123) exhibited excellent performance for enhancing utilization efficiency of P123. This strategy developed a novel route for synthesis of MAs with high efficiency and low-cost.

Obtaining of Mesoporous Aluminosilicates with High Hydrothermal Stability by Composite Organic Templates: Utility and Mechanism

“…6 As we know, active micelles are prerequisite for the assembly of aluminosilicate raw materials. 7,8 On the other hand, active micelles will exist only in low concentration of P123 solution, leading to the low utilization efficiency of both organic template and water. 9 For example, our previous process suffers from high P123 and H 2 O consumption (1.47 and 86 g/g, respectively).…”

“…A series of mesoporous aluminosilicates (MAs) with good hydrothermal stability have been prepared by self-assembly of basic characteristic structure units of microporous zeolite Y by our group. − Much attention has been focused on these materials obtained by this novel strategy because of their distinct textural structures and their potential application in heavy oil catalytic cracking . As we know, active micelles are prerequisite for the assembly of aluminosilicate raw materials. , On the other hand, active micelles will exist only in low concentration of P123 solution, leading to the low utilization efficiency of both organic template and water . For example, our previous process suffers from high P123 and H 2 O consumption (1.47 and 86 g/g, respectively).…”

Hydrophobic Polypropylene Glycol Integration into the Micelles: A General Approach for High Utilization Efficiency of Organic Template

“…P123 is a typical nonionic surfactant composed of hydrophilic PEO blocks and hydrophobic PPO blocks. In previous studies, P123 has been an effective template for obtaining a well-ordered mesophase as the result of hydrophilicity/hydrophobicity balance in acid medium. − On the basis of the above investigations, our group reported the interactions between the hydrophobic chain of SDS and PPO units of P123 . In this strategy, a mixed micelle with a core consisting of SDS hydrophobic units and PPO units and a corona of PEO units was established.…”

“…24−30 On the basis of the above investigations, our group reported the interactions between the hydrophobic chain of SDS and PPO units of P123. 31 In this strategy, a mixed micelle with a core consisting of SDS hydrophobic units and PPO units and a corona of PEO units was established.…”

Depletion Forces Induced by Mixed Micelles of Nonionic Block Copolymers and Anionic Surfactants

“…In this work, we now determine how depletion forces may be altered when surfactants bind to a polymer amphiphile when the polymer is well above its normal critical micelle concentration (CMC), using anionic SDS and Pluronic P123 PEO–PPO–PEO triblock copolymers as a model system. Supramolecular assemblies formed by polymer/surfactant complexation in solution have been thoroughly studied and reviewed. − Complexation of Pluronic micelles with SDS proceeds via a progression of Pluronic micelle disintegration, whereby the larger polymer micelles experience three different binding regimes as a function of increasing SDS concentration: polymer-rich mixed micelles, succeeded by a bimodal distribution of polymer-rich and SDS-rich mixed micelles, and finally SDS-rich mixed micelles. − This was originally described as a “peel-off” process to convey the idea that the mixed micelles contain fewer polymer chains than the surfactant-free polymer micelles do . Pluronic P123 has a significantly lower CMC (and lower critical micelle temperature for a given concentration) than the F108 copolymer that was previously investigated for depletion force synergism, and it has been shown to exhibit this three-regime micellar interaction with SDS. , …”