Recovery of Fumaric Acid from Industrial Wastewater by Chemical Extraction and Stripping

Abstract

The study on chemical extraction and stripping for the recovery of fumaric acid from low concentration organic acid wastewater has been carried out. The parameters influencing the extraction efficiency were investigated, including extractant concentration, the initial pH, the volume ratio of water to oil (W/O), the extraction temperature, and the concentration of n‐octanol. The heat effect of the extraction process, the formation of acid‐amine complexes, and the corresponding equilibrium constant were determined. In the optimum condition that kerosene/N₇₃₀₁/n‐octanol was 2:2:1, pH was 0.5, W/O was 1:1, and the temperature was 303K, through chemical extraction and stripping, the COD_cr value of fumaric acid wastewater decreased from 71040 mg/l to 8411 mg/l, and the overall COD_cr removal rate reached 88.16%, and the extraction efficiency of fumaric acid was 70.67%. The extractant was regenerated by a stripping process with 2% NaOH, and the stripping rate almost arrived at 100%. The regenerated extractant was cycled seven times without decreasing extraction efficiency and the stripping rate. And fumaric acid was obtained by adjusting the pH of the salt from stripping. After extraction, the fumaric acid wastewater can be further treated by oxidation or biodegradation to environmentally acceptable levels.     

Preparation of nanoparticles composed of chitosan and its derivatives as delivery systems for macromolecules

Three different kinds of nanoparticles for paracellular transport were prepared using a simple and mild ionic‐gelation method. Sodium tripolyphosphate (TPP) as crosslinking agent was added into three kinds of solutions, which were chitosan solution, physical blending solution of chitosan, and glycidyl trimethylammonium chloride (GTMAC), and O‐(2‐hydroxyl) propyl‐3‐trimethyl ammonium chitosan chloride (O‐HTCC) solution respectively. O‐HTCC was synthesized by coupling of GTMAC to chitosan whose functional groups of the NH₂ groups were protected. The nanoparticles were characterized by transmission electron microscopy, atomic force microscopy, photon correlation spectroscopy, and zeta potential measurement. The results showed that increasing TPP concentration promoted the size of chitosan nanoparticles, a decrease in the size of O‐HTCC nanoparticles incurred on the contrary. The size of O‐HTCC nanoparticles is slightly bigger than that of pure chitosan nanoparticles, and smaller than that of physical blending nanoparticles (PBN). Bovine serum albumin (BSA), as a model protein drug, was incorporated into the nanoparticles. Compared with chitosan nanoparticles and PBN, high BSA loading efficiency (87.5%) and loading capacity (99.5%) are achieved by quaternized chitosan (O‐HTCC) nanoparticles, and the release profile of BSA from nanoparticles has an obvious burst effect and a slowly continuous release phase followed. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

Calcium‐carboxymethyl chitosan hydrogel beads for protein drug delivery system

In this study, carboxymethyl chitosan (CMC) hydrogel beads were prepared by crosslinking with Ca²⁺. The pH‐sensitive characteristics of the beads were investigated by simulating gastrointestinal pH conditions. As a potential protein drug delivery system, the beads were loaded with a model protein (bovine serum albumin, BSA). To improve the entrapment efficiency of BSA, the beads were further coated with a chitosan/CMC polyelectrolyte complex (PEC) membrane by extruding a CMC/BSA solution into a CaCl₂/chitosan gelation medium. Finally, the release studies of BSA‐loaded beads were conducted. We found that, the maximum swelling ratios of the beads at pH 7.4 (17–21) were much higher than those at pH 1.2 (2–2.5). Higher entrapment efficiency (73.2%) was achieved in the chitosan‐coated calcium‐CMC beads, compared with that (44.4%) in the bare calcium‐CMC beads. The PEC membrane limited the BSA release, while the final disintegration of beads at pH 7.4 still leaded to a full BSA release. Therefore, the chitosan‐coated calcium‐CMC hydrogel beads with higher entrapment efficiency and proper protein release properties were a promising protein drug carrier for the site‐specific release in the intestine. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3164–3168, 2007     

Regioselective and green synthesis of nitro aromatic compounds using polymer‐supported sodium nitrite/KHSO4

Polymer supported reagents have become the subject of considerable and increasing interest as insoluble materials in the organic synthesis. Use of polymeric reagents simplifies routine nitration of aromatic compounds because it eliminates traditional purification. In this article, the use of readily available cross‐linked poly(4‐vinylpyridine) supported sodium nitrite, [P₄‐Me] NO₂, as an efficient polymeric nitrating agent in the presence of KHSO₄ is described. A good range of available aromatic compounds were also subjected to nitration in the presence of [P₄‐Me] NO₂/KHSO₄. This reagent is regioselective and chemoselective nitrating polymeric reagent for activated aromatic rings. In this procedure, the work‐up is easy, and the spent polymeric reagent is easily regenerated and reused. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

One Dimensional Coordination Polymer of Nickel(II)-Squarate with N,N,N′,N′-tetramethylethylenediamine, {[Ni(μ-sq)(H2O)2(tmen)]·H2O}n

A novel 1D coordination polymer {[Ni(μ-sq)(H₂O)₂(tmen)]·H₂O}_n (H₂sq = squaric acid and tmen = N,N,N′,N′ -tetramethylethylenediamine) has been synthesized and structurally characterized by X-ray crystallography. The spectral (IR and UV-vis.) and magnetic susceptibility are reported. The structure of the complex consists of the bidentate tmen ligand bound to Ni(II) center and a bridging squarate in the 1,3-bonding mode. The distorted octahedral geometry of Ni(II) is completed by two aqua ligands. The structure contains chains of squarato-O ¹ ,O ³ -bridged polynuclear nickel(II) units held together by intermolecular hydrogen bonds interactions between water molecules and oxygen atoms of squarate ligand forming a novel R6 motif.     

Cobalt(II), Zinc(II) and Cadmium(II)-Squarate Complexes with N-Methylimidazole

Three M(II)-squarate complexes, [Co(sq)(H₂O)(Nmim)₄] (1), [Zn(μ_1,3-sq)(H₂O)₂ (Nmim)₂] _n (2) and [Cd(μ_1,3-sq)(H₂O)₂(Nmim)₂] _n (3) (sq = squarate, Nmim = N-methylimidazole) have been synthesized and characterized by elemental, spectral (IR and UV–Vis.) and thermal analyses. The molecular structures of the complexes have been investigated by single crystal X-ray diffraction technique. The squarate ligand acts as two different coordination modes as a monodentate (in 1) and bis(monodentate) (O ^1– O ³ ) bridging ligand (in 2, 3). The Co(II) atom has a distorted octahedral geometry with the basal plane comprised of three nitrogen atoms of Nmim ligands and a oxygen atom of squarate ligand. The axial position is occupied by a nitrogen atom of Nmim and one aqua ligand. The crystallographic analysis reveals that the crystal structures of 2 and 3 are one-dimensional linear chain polymers along the c and b axis, respectively. The configuration around each metal(II) ions are distorted octahedral geometry with two nitrogen atoms of trans-Nmim, two aqua ligands and two oxygen atoms of squarate-O¹,O³ ligand. These chains are held together by the C–H···π, π···π and hydrogen-bonding interactions, forming three-dimensional network.     

Well‐Defined End‐Functionalized Conjugated Polymers/Oligomers Exhibiting Unique Emission Properties through the End Groups: The Exclusive Synthesis by Combined Olefin Metathesis with Wittig‐type Coupling

Acyclic diene metathesis polymerization using ruthenium–carbene catalysts affords defect‐free, high molecular weight poly(arylene vinylene)s containing all trans olefinic double bonds. The exclusive end‐functionalization in the resultant poly(fluorene vinylene)s or poly(phenylene vinylene)s can be attained by treating the vinyl end groups using a molybdenum–alkylidene catalyst/reagent (through olefin metathesis) followed by addition of various aldehydes (Wittig‐type coupling). Some of these end‐modified conjugated materials display unique emission properties, which are different from the original ones, through an interaction (energy transfer or structural change in the excited state) between the conjugated main chain and the end groups [oligo(thiophene)s, F‐BODIPY, etc.]. Exclusive synthesis of well‐defined, all‐trans end‐functionalized oligo(2,5‐dialkoxy‐1,4‐phenylene vinylene)s [(oligo(phenylene vinylene), alkoxy = O(CH₂)₂OSiⁱ Pr₃, up to 31 repeat units] is demonstrated by adopting a stepwise synthetic approach (olefin metathesis and the subsequent Wittig‐type cleavage). It is clearly demonstrated that their optical properties (especially the fluorescence spectra including photoluminescence quantum yields) are strongly affected by the end groups as well as the conjugation repeat units.     

The Divalent Titanium Complex Ti(O‐i‐Pr)4/2 i‐PrMgX as an Efficient and Practical Reagent for Fine Chemical Synthesis

This account describes synthetic transformations of unsaturated hydrocarbons, such as alkynes, alkenes, and dienes, mediated by the divalent titanium reagent Ti(O‐i‐Pr)₄/2 i‐PrMgX, which proceed _via (ν ²‐alkene)‐ or (ν ²‐alkyne)‐titanium intermediates. Many of these transformations are otherwise difficult or require multi‐step reaction sequences. Since Ti(O‐i‐Pr)₄ and i‐PrMgX are non‐toxic and available in bulk at low price, the reagent satisfies the qualifications for use in large‐scale synthesis. 1 Introduction 2 A General View of the Ti(O‐i‐Pr)₄/2 i‐PrMgX Reagent 3 Generation of an (ν ²‐Alkyne)Ti(O‐i‐Pr)2 and its Utilization as a Vicinal Vinylic Dianion 4 Preparation of Allyl‐ and Allenyltitanium Reagents and their Synthetic Utility 4.1 Allylic Titanium Reagents 4.2 Allenylic Titanium Reagents 5 Intramolecular Nucleophilic Acyl Substitution (INAS) Reactions Mediated by Ti(O‐i‐Pr)₄/2 i‐PrMgX 5.1 Scope of the Reaction 5.2 Synthetic Applications of the INAS Reaction 6 Intra‐ and Intermolecular Coupling of Olefins and Acetylenes 6.1 Intramolecular Reactions 6.2 Intermolecular Reactions 6.3 Tandem Inter‐ and Intramolecular Reactions 7 Summary and Outlook     

Synthesis,characterization, and drug‐release behavior of novel PEGylated bovine serum albumin as a carrier for anticancer agents

To develop a novel pH‐sensitive PEGylated carrier for protein‐based anticancer agents, we modified bovine serum albumin (BSA) with poly(ethylene glycol) citrate ester (PEG–CA) through amidation with its amino groups. Increasing the mixing ratio of albumin from 3 to 6 with respect to PEG–CA resulted in a 2‐fold increase in the degree of albumin modification. Adriamycin (ADR)‐loaded PEG–CA–BSA hydrogels and microparticles were prepared, and the cumulative amounts of ADR released from the PEG–CA–BSA hydrogels (phosphate‐buffered saline, pH 7.4) showed that all the PEG‐CA‐BSA_(x) (x represents degree of substitution of PEG to amino group of albumin, i.e. 26%, 28%, 31% and 49%) hydrogels had lower ADR release rates with a slight initial burst release. During the first 24 h, the cumulative releases were 15.5% for PEG–CA–BSA₍₄₉₎, 24% for PEG–CA–BSA₍₃₁₎, 31% for PEG–CA–BSA₍₂₈₎, and 38% for PEG–CA–BSA₍₂₆₎. Afterward, all the release rates slowed, and they were almost in the following order: PEG–CA–BSA₍₂₆₎ > PEG–CA–BSA₍₂₈₎ > PEG–CA–BSA₍₃₁₎ > PEG–CA–BSA₍₄₉₎. The release rates of ADR from the microparticles were dependent on the amount of glutaraldehyde. According to our findings, a higher PEG–CA/BSA molar ratio led to a reduced cumulative amount of ADR released from the hydrogels, whereas higher release rates were observed for microparticles with a lower amount of BSA in the conjugates in a pH‐dependent manner. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Convenient synthesis of benzamides mediated by poly(4‐vinylpyridine)‐supported benzoyl chloride

The use of polymeric reagents simplifies the routine acylation of amines because it eliminates traditional purification. In this article, the use of readily available crosslinked poly(4‐vinylpyridine)‐supported benzoyl chloride as an acylating agent of amines in the presence of K₂CO₃ in n‐hexane is described. The product was readily obtained by the filtration and evaporation of the solvent. The spent polymeric reagent could be regenerated and reused. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Controlled release of protein from magnetite–chitosan nanoparticles exposed to an alternating magnetic field

In this research, the controlled release of proteins from magnetite (Fe₃O₄)–chitosan (CS) nanoparticles exposed to an alternating magnetic field is reported. Fe₃O₄–CS nanoparticles were synthesized with sodium tripolyphosphate (TPP) molecules as a crosslinking reagent. Bovine serum albumin (BSA) was used as a model protein, and its controlled release studied through the variation of the frequency of an alternating magnetic field. The results show the successful coating of CS and BSA on the Fe₃O₄ nanoparticles with an average diameter of 50 nm. Intermolecular interactions of TPP with CS and BSA were confirmed by Fourier transform infrared spectroscopy. The application of low‐frequency alternating magnetic fields to such magnetic CS nanoparticles enhanced the protein release properties, in which the external magnetic fields could switch on the unloading of these nanoparticles. We concluded that enhanced BSA release from nanoparticles exposed to an alternating magnetic field is a promising method for achieving both the targeted delivery and controlled release of proteins. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43335.     

Highly efficient separation of methane from nitrogen on a squarate‐based metal‐organic framework

Highly selective capture of methane from nitrogen is considered to be a feasible approach to improve the heating value of methane and mitigate the effects of global warming. In this work, an ultramicroporous squarate‐based metal‐organic framework (MOF), [Co₃(C₄O₄)₂(OH)₂] (C₄O₄^2? = squarate), with enhanced negative oxygen binding sites was synthesized for the first time and used as adsorbent for efficient separation of methane and nitrogen. Adsorption performance of this material was evaluated by single‐component adsorption isotherms and breakthrough experiments. Furthermore, density functional theory calculation was performed to gain the deep insight into the adsorption binding sites. Compared with the other state‐of‐the‐art materials, this material exhibited the highest adsorption selectivity (8.5–12.5) of methane over nitrogen as well as the moderate volumetric uptake of methane (19.81 cm³/cm³) under ambient condition. The unprecedented selectivity and chemical stability guaranteed this MOF as a candidate adsorbent to capture CH₄ from N₂, especially for the unconventional natural gas upgrading. © 2018 American Institute of Chemical Engineers AIChE J, 64: 3681–3689, 2018     

Intermolecular interactions between bovine serum albumin and certain water‐soluble polymers at various temperatures

Viscometric behaviors of dextran (Dx), poly(N‐vinyl‐2‐pyrrolidone) (PVP), and poly(ethylene oxide) (PEO) with bovine serum albumin (BSA) in aqueous solutions have been studied at 25, 30, and 35°C. The reduced viscosity and intrinsic viscosity have been experimentally measured for the polymer/water and polymer/BSA/water systems by classical Huggins equation. Measurements of reduced viscosities of the Dx, PVP, and PEO in water have been calculated and all intrinsic viscosities of PEO([η]_PEO) are larger than that of Dx([η]_Dx), and PVP([η]_PVP) in aqueous solutions, at all temperatures. The intrinsic viscosities of PVP, PEO, and Dx were found to be dependent on the concentration of BSA. The presence of BSA (0.05, 0.10, and 0.30 wt %) led to a decrease in the intrinsic viscosities of polymers, at 25, 30, and 35°C. The concentration difference of BSA (Δ[BSA]) is most effective in decreasing the intrinsic viscosities of Dx at 25°C and PEO at 30 and 35°C. In other words, Δ[η] (%) order followed as Dx > PEO > PVP at 25°C and PEO > Dx > PVP at 30 and 35°C. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1554–1560, 2006     

Synthesis of mesoporous α-MnO2 in manganese(II)-based deep eutectic solvent and their application in the absorption of Congo red

Mesoporous alpha-manganese dioxide (α-MnO₂) were synthesized from manganese(II)-based deep eutectic solvent (DES) of MnCl₂?4H₂O and acetamide in a 1:7 molar ratio. The DES can act as solvent and reducing reagent. As-prepared samples were characterized and used as absorbents for the removal of Congo red (CR) from aqueous solutions. Results show that the sample prepared at 70°C (M-70) could remove 93% CR from aqueous solutions in 30 min. The maximum adsorption capacity of the M-70 was estimated to be 54.85 mg/g. Finally, the exhausted M-70 can be regenerated by thermal desorption.     

Convenient synthesis of benzoate esters mediated by polymer supported benzoyl chloride

Use of polymeric reagents simplifies routine acylation of alcohols because it eliminates traditional purification. We describe the use of readily available crosslinked poly(N‐benzoyl‐4‐vinylpyridinium)chloride, [P₄VP] COPh, in the solution phase synthesis of esters from alcohols or phenols in the presence of K₂CO₃ in high yields and purity. The products can be obtained by filtration and evaporation of the solvent and the polymeric reagent can be regenerated. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

An efficient method for nitration of aromatic compounds over solid acid and polymer‐supported sodium nitrite

A variety of aromatic compounds are nitrated under heterogeneous conditions using a polymer‐supported hydrochloric acid, [P₄‐(VP)]HCl, with a polymer‐supported sodium nitrite, [P₄‐VP]NO₂, or sodium nitrite in ethanol at room temperature with high yields. This methodology is useful for nitration of activated aromatic compounds. In this procedure, the work‐up is very easy, and the spent polymeric reagent can be regenerated and reused. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Characterization of novel quaternary chitosan derivative nanoparticles loaded with protein

The objective of this work was to characterize a novel quaternary chitosan derivative [O‐(2‐hydroxyl) propyl‐3‐trimethyl ammonium chitosan chloride (O‐HTCC)] nanoparticle system. O‐HTCC nanoparticles were prepared with a simple and mild ionic gelation method upon the addition of a sodium tripolyphosphate solution to a low‐molecular‐weight O‐HTCC solution. Highly cationic chitosan nanoparticles were prepared. Bovine serum albumin (BSA), a model protein drug, was incorporated into the nanoparticles. The physicochemical properties of the nanoparticles were determined with transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier transform infrared analysis, differential scanning calorimetry, and X‐ray diffraction (XRD) patterns. The results showed that increasing the BSA concentration from 1.5 to 2.5 mg/mL promoted the BSA encapsulation efficiency from 57.3% to 87.5% and the loading capacity from 70.2% to 99.5%. Compared with the chitosan nanoparticles, the O‐HTCC nanoparticles had lower burst release. TEM revealed that the BSA‐loaded O‐HTCC nanoparticles were smaller than the O‐HTCC nanoparticles when the BSA concentration was 1.5 mg/mL; SEM showed that the size of the BSA‐loaded O‐HTCC nanoparticles was mostly affected by the BSA concentration, and the increase in size occurred with the concentration increasing. Thermograms and XRD of the BSA‐loaded nanoparticles suggested that polyelectrolyte–protein interactions increased with the BSA concentration increasing and greater chain realignment in the BSA‐loaded nanoparticles. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

The effect of process variables on the morphology and release characteristics of protein‐loaded PLGA particles

Poly(lactide‐co‐glycolide) (PLGA 75 : 25), IV 0.94 dL/g was chosen as the matrix of the microparticles. Bovine serum albumin (BSA) (Fraction V) as the model drug was incorporated in the microparticles by a W/O/W emulsification and solvent evaporation technique. The effect of the various preparation parameters on particle morphology, drug loading efficiency, and drug release profiles of the resultant microparticles were examined. Particle size varied from 5 to 60 μm. The final morphology of the microparticles varied dramatically with preparation variables such as equipment used to produce the primary emulsion (W1/O) and the water‐to‐oil ratio (W1/O) in the primary emulsion. In general, the viscosity of the primary emulsion had a significant effect on the porosity of particles produced. The release of BSA showed a strong relationship with the preparation parameters of microparticles, partly due to the morphological effects. For example, microparticles made from the vortex mixer that was used to disperse inner aqueous phase (W1) to oil phase (O) showed a lower burst effect than that made from the homogenizer because of its better surface morphology. W1/O ratio, speed of dispersing the primary emulsion into W2, PLGA concentration, and different matrix materials also affected the drug release profiles. In all the samples studied here, only diffusion‐controlled release was observed. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3053–3061, 2006     

A New SiF–Dipropargyl Glycerol Scaffold as a Versatile Prosthetic Group to Design Dimeric Radioligands: Synthesis of the [18F]BMPPSiF Tracer to Image Serotonin Receptors

A novel SiX–dipropargyl glycerol scaffold (X: H, F, or ¹⁸F) was developed as a versatile prosthetic group that provides technical advantages for the preparation of dimeric radioligands based on silicon fluoride acceptor pre‐ or post‐labeling with fluorine‐18. Rapid conjugation with the prosthetic group takes place in microwave‐assisted click conjugation under mild conditions. Thus, a bivalent homodimeric SiX–dipropargyl glycerol derivatized radioligand, [¹⁸F]BMPPSiF, with enhanced affinity was developed by using click conjugation. High uptake of the radioligand was demonstrated in 5‐HT_1A receptor‐rich regions in the brain with positron emission tomography. Molecular docking studies (rigid protein–flexible ligand) of BMPPSiF and known antagonists (WAY‐100635, MPPF, and MefWAY) with monomeric, dimeric, and multimeric 5‐HT_1A receptor models were performed, with the highest G score obtained for docked BMPPSiF: ?6.766 as compared with all three antagonists on the monomeric model. Multimeric induced‐fit docking was also performed to visualize the comparable mode of binding under in vivo conditions, and a notably improved G score of ?8.455 was observed for BMPPSiF. These data directly correlate the high binding potential of BMPPSiF with the bivalent binding mode obtained in the biological studies. The present study warrants wide application of the SiX–dipropargyl glycerol prosthetic group in the development of ligands for imaging with enhanced affinity markers for specific targeting based on peptides, nucleosides, and lipids.     

Toward Angiogenesis Inhibitors Based on the Conjugation of Organometallic Platinum(II) Complexes to RGD Peptides

A novel conjugate between a cyclometalated platinum(II) complex with dual antiangiogenic and antitumor activity and a cyclic peptide containing the RGD sequence (‐Arg‐Gly‐Asp‐) has been synthesized by combining solid‐ and solution‐phase methodologies. Although peptide conjugation rendered a non‐cytotoxic compound in all tested tumor cell lines (± α_Vβ₃ and α_Vβ₅ integrin receptors), the antiangiogenic activity of the Pt‐c(RGDfK) conjugate in human umbilical vein endothelial cells at sub‐cytotoxic concentrations opens the way to the design of a novel class of angiogenesis inhibitors through conjugation of metallodrugs with high antiangiogenic activity to cyclic RGD‐containing peptides or peptidomimetic analogues.