Fabrication of CMC-g-PAM Superporous Polymer Monoliths via Eco-Friendly Pickering-MIPEs for Superior Adsorption of Methyl Violet and Methylene Blue

Abstract

A series of superporous carboxymethylcellulose-graft-poly(acrylamide)/palygorskite (CMC-g-PAM/Pal) polymer monoliths presenting interconnected pore structure and excellent adsorption properties were prepared by one-step free-radical grafting polymerization reaction of CMC and acrylamide (AM) in the oil-in-water (O/W) Pickering-medium internal phase emulsions (Pickering-MIPEs) composed of non-toxic edible oil as a dispersion phase and natural Pal nanorods as stabilizers. The effects of Pal dosage, AM dosage, and co-surfactant Tween-20 (T-20) on the pore structures of the monoliths were studied. It was revealed that the well-defined pores were formed when the dosages of Pal and T-20 are 9–14 and 3%, respectively. The porous monolith can rapidly adsorb 1,585 mg/g of methyl violet (MV) and 1,625 mg/g of methylene blue (MB). After the monolith was regenerated by adsorption-desorption process for five times, the adsorption capacities still reached 92.1% (for MV) and 93.5% (for MB) of the initial maximum adsorption capacities. The adsorption process was fitted with Langmuir adsorption isotherm model and pseudo-second-order adsorption kinetic model very well, which indicate that mono-layer chemical adsorption mainly contribute to the high-capacity adsorption for dyes. The superporous polymer monolith prepared from eco-friendly Pickering-MIPEs shows good adsorption capacity and fast adsorption rate, which is potential adsorbent for the decontamination of dye-containing wastewater.

Preparation of Carboxymethyl Cellulose-Based Macroporous Adsorbent by Eco-Friendly Pickering-MIPEs Template for Fast Removal of Pb2+ and Cd2+

“…Ikem et al (2010b, 2011) have reported that introducing a small amount of surfactant (~5% of the continuous phase volume) to stabilize Pickering HIPEs cooperatively with particles before polymerization will reduce the void sizes of the poly-Pickering HIPEs and results in materials with large pore throats and permeability. Otherwise, the permeability and connectivity of the poly-MIPEs can be adjusted by changing the content of nanoparticles or introducing an appropriate amount of surfactant (Wang et al, 2017a,b). According to the preceding discussion, in this study, we reported a new strategy for fabrication of macroporous material from Pickering-MIPEs, which is stabilized by montmorillonite (MMT) together with nonionic surfactant, and non-toxic low-cost flaxseed oil was used as emulsion in disperse phase.…”

Highly Efficient Adsorption of Phenylethanoid Glycosides on Mesoporous Carbon

“…The parameters of the isotherm models were summarized in Table 3. The Langmuir model was more better than the Freundlich model for describing the adsorption data of PhGs on CMK-3, which indicated that the adsorption of the PhGs on the CMK-3 was a simple monolayer adsorption process (Wang F. et al, 2017). In addition, the presence of oxygen-containing functional groups on the surface of CMK-3 enhanced the adsorption of PhGs.…”

Preparation of Macroporous Adsorbent Based on Montmorillonite Stabilized Pickering Medium Internal Phase Emulsions

“…Typically, macroporous carboxymethyl cellulose-g-poly(acrylamide)/montmorillonite (CMC-g-PAM/MMT) monolith was prepared based on Pickering MIPEs, which stabilized with 5% of Mt and 4% of Tween-20 (Wang et al 2017). The obtained monolithic polymers were washed with acetone for 12 h and then immersed into 0.5 M NaOH aqueous alcohol solution (V water /V alcohol = 3/7) for 24 h to transfer the amide group to carboxyl.…”