Preparation method of amide group modified polystyrene-based ultrahigh crosslinking adsorption resin

Abstract

The invention discloses a preparation method of an amide group modified polystyrene crosslinking resin. The method comprises the following steps: preparing an ester group modified precursor resin by asuspension polymerization of a water phase and an oil phase, adding a swelling agent and a Lewis acid catalyst to the precursor resin for a Friedel-Crafts reaction to obtain a post-crosslinking resin, and adding an aminating agent to the post-crosslinking resin for an amination reaction to prepare the cross-linking resin. In the preparation method, ester monomers containing double bonds are introduced, polarity of the resin is improved, numbers of micropore and mesoporous of the resin are increased by the Friedel-Crafts crosslinking reaction, and amide groups are formed by introducing the aminating agent. The specific surface area of the adsorbent can reach to be 900-1500 m2 / g, the pore capacity is 1.012-1.412 cm<3> / g, and the average pore size is 1-20 nm. The hydrophobic force and hydrogen bond action with adsorbed substances are easy to form when adsorbing, thus the adsorption performance of the resin is improved. The preparation process is simple, and reaction conditions are easy to control, so that the resin can be suitable for industrialized production.

Description

technical field [0001] The invention belongs to the field of macromolecular materials, and in particular relates to a preparation method of amide group-modified styrene-based ultra-high cross-linking adsorption resin. Background technique [0002] 5-Hydroxymethylfurfural (5-hydroxymethylfurfural, referred to as 5-HMF) is a multifunctional compound containing active groups such as aldehyde groups and methylol groups, which can undergo hydrogenation, oxidation, esterification, halogenation, polymerization, Hydrolysis and other reactions, is an important biomass platform compound. 5-Hydroxymethylfurfural can also be used as a raw material for the synthesis of various high value-added compounds, and is widely used in the fields of synthetic polymers, drugs, resins, plastics, and fuel additives. For example, 5-hydroxymethylfurfural is oxidized to obtain 2,5-furandicarboxylic acid (FDCA). FDCA is widely used in the synthesis of polyester materials to get rid of the excessive depe...

AI Technical Summary

Problems solved by technology

At present, the separation methods commonly used to separate 5-hydroxymethylfurfural include distillation, solution extraction, membrane separation, adsorption, etc. Due to the high boiling point of 5-hydroxymethylfurfural, distillation separation has the disadvantages of high energy consumption and complicated process; solution extraction is It requires a large amount of solvent and takes a long time; membrane separation is not widely used due to its high price and easy contamination of the membrane; the adsorption separation process is based on the different forces of the adsorbent on different adsorbates; the adsorption separation method is simple to operate and low in cost. is one of the most promising separation methods

The key to adsorption separation is to select a suitable adsorbent. Commonly used adsorbents include zeolite, activated carbon, ion exchange resin, ultra-high cross-linked resin, etc. Activated carbon and zeolite are a type of non-specific adsorbent, which cannot be selectively adsorbed in aqueous solution. Adsorption of 5-hydroxymethylfurfural, and ion exchange resin will produce a large amount of acid-base wastewater when regenerated. These shortcomings limit the wide application of activated carbon, zeolite, and ion exchange resin in industry to a certain extent.

Ultra-high cross-linked adsorption resin has a rigid skeleton structure, and has the characteristics of stable physical and chemical properties, high mechanical strength, and easy regeneration and recycling. It is a new type of composite functional material. At present, ultra-high cross-linked adsorption resin Most of the skeleton structure is polystyrene. Due to the strong hydrophobicity of polystyrene, it needs to be pretreated with polar reagents before use, which increases the complexity and cost of operation. At the same time, polystyrene is used as the skeleton structure. The ultra-high cross-linked adsorption resin has a small adsorption capacity for polar substances with high solubility, and the yield of the target product is low during the desorption process, and the operation is very complicated, which is not conducive to actual production and utilization.

Prior art CN201410171630.5 discloses a preparation method and application of an acetamide-modified ultra-high cross-linked adsorption resin. The resin uses styrene as a monomer as a skeleton, and is successively modified by two steps of amination and acetylation. , the obtained resin has good selective adsorption to phenol, but this preparation method still uses chloromethyl methyl ether as the chloromethylation reagent in the preparation process of Friedel-Crafts post-crosslinking adsorption resin, and chloromethyl methyl ether has a strong Disadvantages such as irritating, highly toxic, volatile and carcinogenic, there are serious safety hazards, which are not conducive to the actual industrial production and application of post-crosslinking resins

Moreover, it is necessary to strictly control the mass percentage of chlorine in the resin, and the specific surface area and pore volume of the resin obtained after amidation are reduced, which affects the adsorption performance.

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