Organic solvents, such as N-methyl-2-pyrrolidone (NMP) and dimethylacetamide (DMAc), have been traditionally used to fabricate polymeric membranes. These solvents may have a negative impact on the environment and human health; therefore, using renewable solvents derived from biomass is of great interest to make membrane fabrication sustainable. Methyl-5-(dimethylamino)-2-methyl-5-oxopentanoate (Rhodiasolv PolarClean) is a bio-derived, biodegradable, nonflammable and nonvolatile solvent. Polysulfone is a commonly used polymer to fabricate membranes due to its thermal stability, strong mechanical strength and good chemical resistance. From cloud point curves, PolarClean showed potential to be a solvent for polysulfone. Membranes prepared with PolarClean were investigated in terms of their morphology, porosity, water permeability and protein rejection, and were compared to membranes prepared with traditional solvents. The pores of polysulfone/PolarClean membranes were sponge-like, and the membranes displayed higher water flux values (176.0 ± 8.8 LMH) along with slightly higher solute rejection (99.0 ± 0.51%). On the other hand, PSf/DMAc membrane pores were finger-like with lower water flux (63.1 ± 12.4 LMH) and slightly lower solute rejection (96 ± 2.00%) when compared to PSf/PolarClean membranes.
(1) Different methods have been applied to fabricate polymeric membranes with non-solvent induced phase separation (NIPS) being one of the mostly widely used. In NIPS, a solvent or solvent blend is required to dissolve a polymer or polymer blend. N-methyl-2-pyrrolidone (NMP), dimethylacetamide (DMAc), dimethylformamide (DMF) and other petroleum-derived solvents are commonly used to dissolve some petroleum-based polymers. However, these components may have negative impacts on the environment and human health. Therefore, using greener and less toxic components is of great interest for increasing membrane fabrication sustainability. The chemical structure of membranes is not affected by the use of different solvents, polymers, or by the differences in fabrication scale. On the other hand, membrane pore structures and surface roughness can change due to differences in diffusion rates associated with different solvents/co-solvents diffusing into the non-solvent and with differences in evaporation time. (2) Therefore, in this review, solvents and polymers involved in the manufacturing process of membranes are proposed to be replaced by greener/less toxic alternatives. The methods and feasibility of scaling up green polymeric membrane manufacturing are also examined.
Petroleum-derived solvents commonly used in membrane fabrication are often hazardous and toxic, so the investigation of safer alternatives is important. In this study, two low-hazard solvents, methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate (Rhodiasolv ® PolarClean) and gamma-valerolactone (GVL), were investigated as sole solvents and as This contribution was identified by Lan Ying Jiang (Central South University-China) as the Best
The
state-of-the-art manufacturing process of making lithium ion
batteries (LIBs) uses a toxic organic and petroleum-derived solvent, N-methylprrolidone (NMP), to dissolve polyvinylidene fluoride
(PVDF) to form a slurry consisting of active materials and conductive
agents. Using viscosity and electrochemical measurements, scanning
electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS),
we show that the NMP solvent may be replaced by a low toxicity solvent,
dimethyl sulfoxide (DMSO), without altering the conventional LIB manufacturing
process. The slurries made using DMSO have similar rheological behavior,
similar viscosity values, and wettability on the current collector
as those made using NMP. The electrochemical behavior of the NMC electrodes
made using the two solvents, including their cycling performance,
are also similar. Replacing NMP with DMSO thus provides an opportunity
to reduce the environmental hazards and cost of the LIB manufacturing.
Many organisms possess the ability
to produce metal-binding proteins
to absorb cadmium. Metallothioneins, an important family of cysteine-rich
metal-binding proteins, have been isolated and well characterized.
However, Lentinula edodes may have
a different type of cadmium-binding protein that contains fewer cysteine
residues. In the present study, we purified a cadmium-binding protein
from L. edodes (LECBP) by gel filtration
and anion exchange chromatography and then identified LECBP by LC–MS/MS.
We found LECBP to be a novel cadmium-binding protein, which contained
220 amino acid residues but no cysteine residue. LECBP had a high
binding affinity for Cd(II) with a K
d value
of 97.3 μM. The percentages of α-helix, β-sheet,
β-turn, and random coil in LECBP were 15.7%, 39.4%, 8.0%, and
37.1%, respectively. In addition, high temperatures and an acidic
environment influenced the conformation of LECBP. Our results will
thus provide a new perspective to understand the mechanism of cadmium
accumulation in L. edodes.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.