Synthesis and Characterization of Molecularly Imprinted Nanoparticle Polymers for Selective Separation of Anthracene

Advances in water treatment technologies for removal of polycyclic aromatic hydrocarbons: Existing concepts, emerging trends, and future prospects

In the last two decades, environmental experts have focused on the development of several biological, chemical, physical, and thermal methods/technologies for remediation of PAH-polluted water. Some of the findings have been applied to field-scale treatment, while others have remained as prototypes and semi-pilot studies. Existing treatment options include extraction, chemical oxidation, bioremediation, photocatalytic degradation, and adsorption (employing adsorbents such as biomass derivatives, geosorbents, zeolites, mesoporous silica, polymers, nanocomposites, and graphene-based materials). Electrokinetic remediation, advanced phytoremediation, green nanoremediation, enhanced remediation using biocatalysts, and integrated approaches are still at the developmental stage and hold great potential. Water is an essential component of the ecosystem and highly susceptible to PAH contamination due to crude oil exploration and spillage, and improper municipal and industrial waste management, yet comprehensive reviews on PAH remediation are only available for contaminated soils, despite the several treatment methods developed for the remediation of PAH-polluted water. This review seeks to provide a comprehensive overview of existing and emerging methods/technologies, in order to bridge information gaps toward ensuring a green and sustainable remedial approach for PAH-contaminated aqueous systems. PRACTITIONER POINTS: Comprehensive review of existing and emerging technologies for remediation of PAH-polluted water. Factors influencing efficiency of various methods, challenges and merits were discussed. Green nano-adsorbents, nano-oxidants and bio/phytoremediation are desirous for ecofriendly and economical PAH remediation. Adoption of an integrated approach for the efficient and sustainable remediation of PAH-contaminated water is recommended.

Glutathione Surface Molecularly Imprinted Polymer from CLX1180 via Three Modes of Polymerization for Selective Adsorption of Glutathione

A novel glutathione (GSH) surface molecularly imprinted polymer (SMIP) was prepared using modified macroporous adsorption resin (MAR) CLX1180 as a solid substrate, glutathione as a template, acrylamide (AM) and N-vinyl pyrrolidone (NVP) as functional monomers, and N,N'-methylenebisacrylamide (NMBA) as a cross-linker. The reaction could be initiated by three different ways, using CLX1180, GSH, and both, which was proved by the experimentation. The morphology and structure of this polymer were characterized by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and time-of-flight mass spectrometry (TOF-MS). The maximum adsorption capacity of GSH approached 39.03 mg·g-1, and the separation degree related to l-cysteine was as high as 4.18. Pseudo-first-order and Langmuir models were well fitting the adsorption properties. GSH-SMIP could be used for three adsorption/desorption cycles with only a slight decrease of adsorption capacity.

Nanotechnology-based sorption and membrane technologies for the treatment of petroleum-based pollutants in natural ecosystems and wastewater streams

Petroleum processing wastewater (PPW) is a complex mixture of free, soluble, and emulsive hydrocarbons that often contain heavy metals and/or solid particles. As these hazardous constituents can accumulate in human beings and the environment, exposure to the PPW can have harmful effects in various respects. The use of environmental nanotechnologies (E-Nano) is considered an attractive option to resolve the problems associated with PPW. Among different treatment technologies, E-Nano-based sorption (adsorption/absorption) and membrane filtration approaches have been proven to have outstanding efficacy in remediation of PPW pollutants. It is, however, crucial to determine the appropriate technological option (e.g., low-cost operational conditions) for the practical application of such technologies. In this review, the potential of E-Nano-based sorption and membrane technologies in the treatment of various PPW pollutants is discussed based on their performances in comparison to traditional technologies. Their suitability is evaluated further in relation to their merits/disadvantages and economic feasibility with the goal of constructing a perspective map to efficiently implement the E-Nano technologies.

Quercetin Recovery from Onion Solid Waste via Solid-Phase Extraction Using Molecularly Imprinted Polymer Nanoparticles

The present study deals with the valorization of the onion solid waste (i. e. peel) by extracting quercetin (Qu) compound, as a natural antioxidant food ingredient. It is used as a raw material for cosmetic, fine chemical and pharmaceutical industries. The onion peel, as a solid waste, is a highly rich source of Qu that is a valuable source of many useful biological properties, including antioxidant, anti-inflammatory, antiviral, antibacterial and antimicrobial properties. For this purpose, Qu molecular-imprinted polymer nanoparticles (Qu–MIP NPs) and its corresponding non-imprinted polymer (NIP) were prepared using precipitation/polymerization method. The prepared Qu–MIP NPs and its corresponding NIP were characterized using Fourier transform infrared spectrometer, scanning electron microscopy and high-resolution transmission electron microscope. The prepared Qu–MIP NPs and its corresponding NIP could successfully rebind Qu at binding capacities of 60 and 10.0 mM/g, respectively. Thus, the prepared Qu–MIP NPs could successfully recover 260 mg Qu from 1 kg onion peel.

Synthesis and characterization of a molecularly imprinted polymer for the isolation of the 16 US-EPA priority polycyclic aromatic hydrocarbons (PAHs) in solution

A smart sorbent consisting of benzo[k]fluoranthene-imprinted and indeno[1 2 3-cd]pyrene-imprinted polymers mixed at 1:1 (w/w) was successfully screened from several cavity-tuning experiments and used in the isolation of polycyclic aromatic hydrocarbons from spiked solution. The polymer mixture showed high cross selectivity and affinity towards all the 16 US-EPA priority polycyclic aromatic hydrocarbons. The average extraction efficiency from a cyclohexane solution was 65 ± 13.3% (n = 16, SD). Batch adsorption and kinetic studies confirmed that the binding of polycyclic aromatic hydrocarbons onto the polymer particles resulted in formation of a monolayer and that the binding process was the rate limiting step. The imprinted polymer performance studies confirmed that the synthesized polymer had an imprinting efficiency of 103.9 ± 3.91% (n = 3, SD). A comparison of the theoretical number of cavities and the experimental binding capacity showed that the overall extent of occupation of the imprinted cavities in the presence of excess polycyclic aromatic hydrocarbons was 128 ± 6.45% (n = 3, SD). The loss of selectivity was estimated at 2.9% with every elution cycle indicating that the polymer can be re-used several times with limited loss of selectivity and sensitivity. The polymer combination has shown to be an effective adsorbent that can be used to isolate all the 16 US-EPA priority polycyclic aromatic hydrocarbons in solution.