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in the removal of pollutants present in wastewater. One of the first results published
in 1995 concerned the fact that this material was not a true polymer but a copolymer
with a particular structure with two different molecular mobilities. In 1997, this was
demonstrated for the first time by solid-state NMR spectroscopy. These materials
were composed of a relatively dense, rigid, and hydrophobic cross-linked core and
a more hydrophilic surface, less cross-linked containing long and highly mobile
hydroxyalkylated polymer chains through the homopolymerization of the crosslinking agent. In 1998, cyclodextrin-based materials were used as adsorbents to
efficiently remove organic contaminants from contaminated water. One year later, a
more surprising result showed that a high proportion of cyclodextrin was not necessary to have useful performance in terms of pollutant removal. In 2000, using crosspolarization magic angle spinning with dipolar decoupling and high-resolution
magic angle spinning spectra, we concluded that the mechanism of adsorption can
be explained by the presence of two main interactions: the formation of an inclusion
complex due to the cyclodextrin molecules and the physical adsorption in the polymer network. In 2005, a patent was filed on a process for the synthesis of crosslinked polysaccharides with ionic functional groups for the simultaneous removal
of metals and organic contaminants present at low trace levels in polycontaminated
effluents. At the end of the 2000s, we carried out the first pilot studies demonstrating
that a single cyclodextrin material with amphoteric and ion-exchange properties
could replace two conventional adsorbents to effectively treat multi-contaminated
effluent. In the early 2010s, our group proposed for the first time biomonitoring tests
using plants as bioindicators to determine and compare the toxicity of industrial
effluent from wood, pulp and paper, textile, and surface treatment industries before
and after treatment with a cyclodextrin material. In the mid-2010s, we confirmed
the feasibility of implementing materials for the treatment of discharge waters from
surface treatment industries on an industrial scale.
The purpose of this chapter is to summarize the research conducted over the past
30 years by our research group on water-insoluble cyclodextrin-epichlorohydrin
polymers used as complexing materials to remove contaminants present in aqueous
solutions. It shows the progress of our work and our contribution to a better understanding of these materials. These years were devoted to the synthesis of a series of
water-insoluble materials with different functionalities in the form of gels or beads,
their characterization by innovative solid-state NMR techniques, the demonstration
of their effectiveness as adsorbents in wastewater treatment, and the explanation of
contaminant removal mechanisms according to the type of material used.
Keywords History · Cyclodextrin polymers · Synthesis · Characterization ·
Complexation · Adsorption · Industry
G. Crini
in the removal of pollutants present in wastewater. One of the first results published
in 1995 concerned the fact that this material was not a true polymer but a copolymer
with a particular structure with two different molecular mobilities. In 1997, this was
demonstrated for the first time by solid-state NMR spectroscopy. These materials
were composed of a relatively dense, rigid, and hydrophobic cross-linked core and
a more hydrophilic surface, less cross-linked containing long and highly mobile
hydroxyalkylated polymer chains through the homopolymerization of the crosslinking agent. In 1998, cyclodextrin-based materials were used as adsorbents to
efficiently remove organic contaminants from contaminated water. One year later, a
more surprising result showed that a high proportion of cyclodextrin was not necessary to have useful performance in terms of pollutant removal. In 2000, using crosspolarization magic angle spinning with dipolar decoupling and high-resolution
magic angle spinning spectra, we concluded that the mechanism of adsorption can
be explained by the presence of two main interactions: the formation of an inclusion
complex due to the cyclodextrin molecules and the physical adsorption in the polymer network. In 2005, a patent was filed on a process for the synthesis of crosslinked polysaccharides with ionic functional groups for the simultaneous removal
of metals and organic contaminants present at low trace levels in polycontaminated
effluents. At the end of the 2000s, we carried out the first pilot studies demonstrating
that a single cyclodextrin material with amphoteric and ion-exchange properties
could replace two conventional adsorbents to effectively treat multi-contaminated
effluent. In the early 2010s, our group proposed for the first time biomonitoring tests
using plants as bioindicators to determine and compare the toxicity of industrial
effluent from wood, pulp and paper, textile, and surface treatment industries before
and after treatment with a cyclodextrin material. In the mid-2010s, we confirmed
the feasibility of implementing materials for the treatment of discharge waters from
surface treatment industries on an industrial scale.
The purpose of this chapter is to summarize the research conducted over the past
30 years by our research group on water-insoluble cyclodextrin-epichlorohydrin
polymers used as complexing materials to remove contaminants present in aqueous
solutions. It shows the progress of our work and our contribution to a better understanding of these materials. These years were devoted to the synthesis of a series of
water-insoluble materials with different functionalities in the form of gels or beads,
their characterization by innovative solid-state NMR techniques, the demonstration
of their effectiveness as adsorbents in wastewater treatment, and the explanation of
contaminant removal mechanisms according to the type of material used.
Keywords History · Cyclodextrin polymers · Synthesis · Characterization ·
Complexation · Adsorption · Industry
G. Crini