Acidic Exchange Resin Research Articles

Kinetic Studies of the Glycerolysis of Urea to Glycerol Carbonate in the Presence of Amberlyst-15 as Catalyst

Amberlyst-15, a strong acidic ion-exchange resin, has showed as a potential and an effective catalyst for the glycerolysis process of urea to glycerol carbonate. In this work, the kinetic model of the urea glycerolysis over Amberlyst-15 catalyst was investigated. The kinetic model was developed by considering simultaneous steps of urea dissolution in glycerol, mass transfer of urea and glycerol from the bulk of the liquid into the outer part of the catalyst, diffusion of urea and glycerol into the inner part of the particle through the catalyst pores, and irreversible second order reaction of urea and glycerol on the active sites. The irreversibility of second order reaction of urea glycerolysis was validated and proven. The proposed kinetic model was simulated and validated with the experimental data. The kinetic studies show that mechanism proposed works well. Furthermore, the activation energy was found to be 145.58 kJ.mol−1 and the collision factor was in 8.00×1010 (m3)2.kg−1.mol−1.s−1. The simulation result shows that the predicted liquid temperatures were close to the experimental temperature data. It also gave glycerol concentration profile inside the catalyst particle as a function of glycerolysis time and position. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Side Products in the Water-Tolerant Synthesis of Poly(oxymethylene) Dimethyl Ethers: Formation Kinetics and Implications for Process Design

Poly(oxymethylene) dimethyl ethers (OME) offer excellent fuel properties such as soot-free combustion and are discussed as potential diesel fuels. Formation of side products during their production, a crucial factor for the feasibility of the process, has been of minor consideration so far. This work investigates the formation of side products during the OME synthesis via a recently proposed route from methanol and concentrated aqueous formaldehyde solution over the acidic ion exchange resin Amberlyst 46 as heterogeneous catalyst. Batch experiments under elevated temperatures and pressures and long residence time are carried out. The kinetics of the formation of the side products trioxane, methyl formate, and formic acid are quantified and modeled. Implications for the process design are examined in process simulation studies. Some side products accumulate within the process, and thus, their removal is indispensible. Introducing a purge stream results in 2.7% loss of product at a reactor temperature of 343.15 K, which emphasizes the need for further investigations regarding side product formation under process conditions, advanced removal methods, or improved catalysts.

Synthesis of Biolubricant via Chemical Modification from Vegetable Oil Blend using Heterogeneous Catalyst

Present study reports the synthesis of biolubricant synthesis from the vegetable oil blend [dehydrated castor oil (DCO) and waste ricebran oil (WRBO)] using heterogeneous catalyst and its physico-chemical properties. The biolubricant was synthesized from blend of vegetable oils using two chemical modification processes i.e. synthesizing methyl esters of blend oil using sodium methoxide as catalyst and then epoxidation of synthesized methyl esters using Amberlite IR-120 strongly acidic ion-exchange resin. The biolubricant sample was examined by 1H & 13C NMR and FT-IR analysis. Viscosity index, rheological properties, thermal stability and pour point values of chemical and structurally modified blend oil (i.e. biolubricant) (Tonset = 215 ºC, iodine value (IV) = 197.5, pour point (PP) = -4.5 ºC) showed notable improvement than that from blend oil methyl esters (Tonset = 181 ºC, iodine value (IV) = 167.65, pour point (PP) = -9.5 ºC). Thus, a blend of non-edible oil (dehydrated castor oil) and waste cooking oil (WRBO) is likely to be used potentially as biolubricant basestock for hydraulic applications.

Separation and Purification of Biogenic 1,3-Propanediol from Fermented Glycerol through Flocculation and Strong Acidic Ion-Exchange Resin.

In the present work, was investigated the separation and purification procedure of the biogenic 1,3-propanediol (1,3-PD), which is a well-known valuable compound in terms of bio-based plastic materials development. The biogenic 1,3-PD was obtained as a major metabolite through the glycerol fermentation by Klebsiella pneumoniae DSMZ 2026 and was subjected to separation and purification processes. A strong acidic ion exchange resin in H+ form was used for 1,3-PD purification from the aqueous solution previously obtained by broth flocculation. The eluent volume was investigated considering the removal of the secondary metabolites such as organic acids (acetic, citric, lactic, and succinic acids) and 2,3-butanediol (2,3-BD), and unconsumed glycerol. It was observed that a volume of 84 mL of ethanol 75% loaded with a flow rate of 7 mL/min completely remove the secondary metabolites from 10 mL of concentrated fermented broth, and pure biogenic 1,3-PD was recovered in 128 mL of the eluent.

Catalytic Hydroxyalkylation/Alkylation of 2-Methylfuran with Butanal to Form a Biodiesel Precursor Using Acidic Ion-Exchange Resins

The catalytic hydroxyalkylation/alkylation of 2-methylfuran (2MF) with butanal has been investigated over several acidic ion-exchange resins within the temperature range 50–90 °C and at a stoichiom...

Hydrolysis of Oligosaccharides and Polysaccharides on Sulfonated Solid Acid Catalysts: Relations between Adsorption Properties and Catalytic Activities.

Sulfonated solid acid materials, such as sulfonated carbon catalysts, are promising materials as heterogeneous catalysts for the hydrolysis of esters and polysaccharides in water solvents. The catalytic active site is a sulfonic acid functional group. Compared to conventional strong acidic ion-exchange resin catalysts, sulfonated carbon materials have less sulfonic acid functional groups but higher catalytic activity for hydrolysis of polysaccharides per catalyst weight. However, the details of catalytic properties and the substrate suitability of both catalysts are unclear. In this study, the hydrolytic activities and the adsorption properties of both catalysts were investigated for various oligosaccharides and polysaccharides with varying degrees of polymerization (DP). The catalytic activities for the hydrolysis with increase of the DP of saccharides were found to increase over the sulfonated carbon catalyst but decrease over strong acidic ion-exchange resin catalyst. The inverse catalytic properties attribute to the dependence of the amounts of adsorption and/or penetration of saccharides on the DP. Moreover, the catalytic activity per acidic sites of strong acidic ion-exchange resin is in good agreement with the value obtained by multiplying the catalytic activity of a dilute sulfuric acid by the penetration degrees.

Unraveling the reaction route and kinetics of 3‐methyl‐3‐penten‐2‐one synthesis for synthetic ketone fragrances

AbstractBACKGROUND3‐Methyl‐3‐penten‐2‐one (3M3P) is an indispensable raw material used for the synthesis of OTNE (octahydrotetramethyl acetophenone), a synthetic ketone fragrance known by commercial trade names, such as Iso E Super®, which is one of the most important ingredients in perfumes. This work is the first to unravel the reaction route and kinetics for the synthesis of 3M3P via the cross‐aldol condensation of acetaldehyde with butanone, catalyzed by the heterogeneous acidic ion exchange resin (NKC‐9).RESULTSAn effective method was developed to evaluate this complex reaction system: the reaction routes were determined experimentally from the product structures detected by Gas Chromatography Mass Spectrometry (GC‐MS), and the significance of side reactions were evaluated by the Yoneda group contribution method. The major side reactions are the self‐condensation of acetaldehyde (significant even under optimized reaction conditions) and the cross‐aldol condensation of acetaldehyde with 3M3P (which could be effectively suppressed at high butanone‐acetaldehyde molar ratio). The reaction kinetics was investigated at temperatures of 60–90 °C, catalyst mass fraction of 5 to 15%, and molar ratio of 5–20. At optimized reaction conditions, the yield of 3M3P was up to 90.85%, which is 2.4 times higher than that for the classic homogeneous catalysts (yield <38%).CONCLUSIONAcidic ion exchange resin NKC‐9 is a high‐selective green catalyst for the cross‐aldol condensation of acetaldehyde with butanone. Integrating experimental determination and thermomechanical analysis is an effective method to unravel the main reaction routes for a complex system. © 2020 Society of Chemical Industry (SCI)

Reaction coupling separation for isosteviol production from stevioside catalyzed by acidic ion-exchange resin.

Isosteviol, a prodrug used to be obtained via Wagner-Meerwein rearrangement from steviol with low yield and long reactiontime. Herein, an in-situ separation-coupling-reaction is presented to prepare isosteviol from the natural sweetener stevioside. Simply with in-situ water-washing, the product containing 92.98% purity of isosteviol was obtained with a stevioside conversion of 97.23% from a packet bed reactor without further separation. Within the assayed inorganic acid, organic acids and acidic ionic liquids, the acidic ion-exchange resins provided higher product specificity towards isosteviol. Furthermore, comparing to 5-Fluorouracil, the product presented similar and even stronger inhibition on proliferation of the assayed human cancer cells in a time and dose-dependence by causing cell phase arrest. Isosteviol treatment caused G1 arrest on SGC-7901, HCT-8 and HCT-116 cells, S arrest on HepG2, Huh-7 and HepG3B cells, and G2 arrest on MGC-803 cells, respectively. Reaction coupling separation for isosteviol production catalyzed by acidic ion-exchange resin.

Ion exchange resin-catalyzed synthesis of bridged tetraoxanes possessing in vitro cytotoxicity against HeLa cancer cells

Bridged 1,2,4,5-tetraoxanes were prepared using available acidic ion exchange resin with high yields despite the possibility of peroxide decomposition under heterogeneous conditions. The bridged tetraoxanes demonstrated high cytotoxicity against HeLa cancer cells in vitro, which in some cases was higher than that of cisplatin, artesunate, and dihydroartemisinin.

Characterizing phosphorus availability in waste products by chemical extractions and plant uptake

AbstractBackground: The fertilizer value of phosphorus (P) in waste products relies heavily on its availability to the subsequent crop.Aim: We studied the link between extractable P in waste products and apparent P recovery (APR, i.e., difference in plant P uptake between P amended and un‐amended soils divided by the amount of P added) using spring barley grown on three sandy soils.Methods: The products included sewage sludge, biomass ash, struvite, compost, meat and bone meal, biochar from sewage sludge, and industrial sludge. Soft rock phosphate and triple‐superphosphate (TSP) were included for comparison. Availability of P was characterized by extraction with water and solutions of sodium bicarbonate, citric acid, oxalic acid, hydrochloric acid, ammonium acetate, ammonium fluoride and anion exchange resin membranes. TSP was used to establish mineral‐fertilizer‐equivalents (MFE). Water and bicarbonate extractions were also applied to products incubated with soil before extraction.Results: The APR ranged 26 to 31% for TSP and 0 to 30% for waste products. APR correlated most strongly with bicarbonate extractable P. The correlation increased when products were incubated with soil before extraction.Conclusions: We conclude that bicarbonate extraction is a good indicator of potential P availability. However, interactions between waste products and soil properties modify P availability.

Characterization and application of spherical carbonaceous materials prepared with the use of microwave radiation

A series of new synthetic spherical carbonaceous sorbents has been prepared by carbonization and physical activation of strongly acidic ion exchange resin - Wofatit RH. The carbonaceous materials were prepared using two different variants of thermal treatment - microwave and conventional heating. The samples obtained were characterized using various techniques, i.e. elemental analysis, determination of surface pH as well as the content of oxygen functional groups according to the Boehm titration method. The porous structures of all samples under investigation were characterized by low temperature nitrogen adsorption/desorption. Thermal properties of the spherical carbonaceous materials were investigated using thermogravimetric analysis as well as differential thermogravimetry. Kinetic and sorption studies of the removal of organic dye Bismarck Brown Y by adsorption on the carbonaceous adsorbents were carried out. In order to optimize the sorption effectiveness, the effects of contact time, initial dye concentration, pH of dye solution as well as temperature were studied.The products obtained were spherical carbonaceous materials of surface area ranging from 0.02 to 194 m2/g and pore volume from 0.0001 to 0.18 cm3/g. More favorable textural parameters were revealed by activated carbons obtained with the use of microwave radiation. It was found that the sorption capacity towards Bismarck Brown Y increased with the increasing initial concentration of the dye solution as well as the phases contact time.

Synthesis of poly(oxymethylene) dimethyl ethers from methylal and trioxane over acidic ion exchange resins: A kinetic study

Poly(oxymethylene) dimethyl ethers (POMDME) are fuel additives that can reduce the emissions associated with diesel fuels considerably. POMDME have been synthetized from methylal and trioxane, catalyzed by the acidic ion exchange resin Amberlyst 15. A batch autoclave reactor has been used to carry out experiments conducted up to equilibrium conditions. The resulting POMDME distribution is modelled using the Schulz-Flory distribution theory, which confirms a sequential chain growth with insertion of one formaldehyde molecule at each reaction step. The kinetic experiments were carried out in an isothermal continuous fixed-bed reactor. The influence of temperature (45–80 °C) and space-time (1.6–3.2 kg h/m3) on trioxane conversion and product selectivity was determined. A kinetic model of the reaction has been proposed and validated with the experimental results. It has been demonstrated that trioxane decomposition to formaldehyde is the kinetically limiting step of the reaction scheme, with an activation energy of 112.2 kJ/mol. POMDME chain propagation reactions are in equilibrium under the conditions studied.

Tall Oil Fatty Acid Epoxidation Using Homogenous and Heterogeneous Phase Catalysts

Tall oil fatty acids were epoxidized by in-situ generation of peracetic acid in the presence of two different acidic catalysts, commonly used catalyst—sulfuric acid and ion exchange resin. The described epoxidation was carried out without the use of organic solvents to comply with the principles of Green chemistry. The epoxidation process was monitored by the change of the relative oxirane conversion and alkenic unsaturation. Furthermore, the changes in the chemical structure of the epoxidized tall oil fatty acids were investigated using FTIR spectroscopy. It was shown that ion exchange resin Amberlite IR-120 H catalyst was superior to sulfuric acid catalyst as it delivered fewer by-products from oxirane group opening reactions. The oxirane value reached up to 2.31 mmol/g of epoxy groups, which is 41.9% of theoretically possible oxirane oxygen yield, when tall oil was epoxidized using Amberlite IR-120 H. The reusability of ion exchange resin was also studied, the 6.2% decrease in relative oxirane conversion value was registered after Amberlite IR-120 H was reused up to 10 times.

High yield of isosorbide production from sorbitol dehydration catalysed by Amberlyst 36 under mild condition

Isosorbide (ISB), one of the important polyols, can be produced through the sequential intramolecular dehydration of sorbitol (SL) derived from an abundance renewable biomass resources. The advantages of its rigid structure have granted the ISB a wide application in the polymer industries. An acidic catalyst in the liquid phase was conventionally used in the dehydration process. This homogeneously catalysed reaction gave low ISB yield and required additional downstream processes to separate the catalyst. The present study employed solid acidic ion exchange resin, Amberlyst 36 in the SL dehydration at a mild condition. The effect of important operating parameters such as stirring speed, catalyst loading, temperature and reaction time was investigated. The increase of catalyst loading from 5 to 7 wt% did not significantly affect the ISB yield. A higher temperature increased the reaction rate whereas a prolonged reaction time increased the conversion of SL and yield of ISB to the maximum. In terms of giving a higher ISB yield during SL dehydration, AM 36 was found to outperform the other resin catalysts reported in the literature. Both SL conversion and ISB yield of >99% were recorded after a 4 h reaction at 423 K with catalyst loading of 5 wt% and stirring speed of 300 RPM. The reaction kinetics was evaluated under a mass transfer resistances free condition at the reaction temperature ranged from 373 K to 423 K. The kinetic data well fitted to the Langmuir-Hinshelwood (LH2) model that took side reaction into account. The activation energy for dehydration SL to ST, dehydration ST to ISB and dehydration of SL to other side products such as humins were 109.22, 109.46 and 104.17 kJ/mol respectively.

Opportunities for coupled electrochemical and ion-exchange technologies to remove recalcitrant micropollutants in water

Micropollutants are found in many waters at concentrations that are concerning for living and environmental systems. They are usually characterised as being persistent and are generally difficult to remove from the water using traditional techniques. In this work, we investigate a treatment technology that couples electrooxidation of micropollutants with subsequent absorption of charged products and remaining compounds through a mixed strong acid and strong base ion exchange resin. The results clearly show that carbon fibre is a promising electrode material. Electrooxidation of the drug Ibuprofen using carbon fibre in a coulombic efficiency of 13 mC/ppm removed 71% of the compound after two hours (down to 29 ppm). The addition of sodium chloride led to a near doubling of the pseudo-first order reaction rate from 1.7 to 3.0 10−4 s−1. A mix of Ibuprofen and the pesticide Diuron showed similarly promising results and while the overall oxidation decreased the positive effect of sodium chloride was present. Strikingly, coupling electrooxidation with a mixed bed ion exchange resin removed both compounds, decreasing levels of Diuron to below the limit of detection (18 ppb) and Ibuprofen down to 0.8 ppm. The approach shows potential as a treatment technology for the removal of complex pollutants in water.

Synthesis of quinazoin-4-ones through an acid ion exchange resin mediated cascade reaction.

An interesting cascade reaction of N-(2-(4,5-dihydrooxazol-2-yl)phenyl)benzamide in the presence of an acid ion exchange resin is described. In this reaction, a range of substrates bearing various substituent groups are well compatible. This work provides a green and atom-economical alternative approach for the synthesis of quinazolin-4-ones in good yields.

Study on aluminum removal through 5-sulfosalicylic acid targeting complexing and D290 resin adsorption

In-situ leaching process are often used to extract rare earth resources for ion-adsorbed rare-earth ore, unfortunately this leaching process also extracts a large amount of non-rare earth impurities such as aluminum, iron and etc. In this paper, 5-sulfosalicylic acid was selected as a complexing agent to complex aluminum ions selectively, and then the aluminum complexing ion could be removed by D290 resin adsorption, which achieved the aluminum removal in the rare-earth leaching solution. The complexation reaction of 5-sulfosalicylic acid with aluminum ion was studied by ultraviolet spectrophotometry which showed that the coordination ratio of 5-sulfosalicylic acid to aluminum ion was 1:1. The effects of solution pH, amount of 5-sulfosalicylic acid and D290 anion exchange resin, flow rate and reaction time on the adsorption results were investigated comprehensively. The results showed that the final pH of the solution was 3.5, the ratio of 5-sulfosalicylic acid to aluminum was 1.5:1, flow rate was 0.2 mL/min and reaction time was 120 min, the aluminum removal was 75.63% and the rare earth loss was less than 5%. The adsorption kinetics of aluminum ions by 5-sulfosalicylic acid-D290 resin showed that the adsorption of aluminum ions conformed to the second-order adsorption kinetics model.

Characterization of the buccal and gastric transit of orally disintegrating tablets in humans using gamma scintigraphy

The present study characterized the buccal cavity-emptying and gastric-emptying kinetics of orally disintegrating tablets (ODTs) in fasted humans using gamma scintigraphy. 111Indium-diethylenetriaminepentaacetic acid and technetium-99 m-labeled ion exchange resin were used as a model soluble drug and insoluble pellet-type drug, respectively, and housed in ODTs. These ODTs were then administered to human subjects with or without ingestion of water, after which scintigraphic images were collected in order to characterize the buccal and gastric transit of the radioactivity. The oral disintegration of the ODTs was extremely rapid, with a mean time of ≤1 min. The buccal emptying of the radioactivity was most rapid for the ODT with a water-soluble radiolabel; however, the ODTs with water-insoluble radiolabels showed buccal emptying with median half-times of ≤2.5 min. The ODT with the soluble radiolabel in subjects without water ingestion showed the most rapid gastric emptying compared with the ODTs with the insoluble radiolabels, the gastric-emptying time of which was highly variable. Further, water ingestion did not markedly affect the gastric-emptying time of the tablets with the water-soluble model drug. The observations in the present clinical study will help clarify the in vivo performance of ODTs in humans.

Sn exchanged acidic ion exchange resin for the stable and continuous production of 5-HMF from glucose at low temperature

This report discusses the easy and cheap preparation of SnCl2 exchanged Brønsted acidic Amberlyst-15 ion exchange resin prepared by ion exchange of an aqueous SnCl2 solution at room temperature. The prepared materials were tested in the conversion of sugars, being glucose, fructose and saccharose to 5-HMF at low temperature conditions (120 °C) and high sugar concentrations (30 wt. %). Materials showed activity in the conversion of glucose, fructose and saccharose. The effect of the repeating exchange procedures on the catalytic performance was studied under batch and continuous flow conditions. The physicochemical properties of the Amberlyst materials were characterized by various techniques, among them NH3-TPD, N2 physisorption and XRF experiments. The superior stability over 120 h and the selectivity towards 5-HMF of the SnCl2 exchanged Amberlyst material under continuous flow conditions was partially attributed to a reduced concentration of the total acid site concentration, preventing products to react further towards poorly defined humin-type products.

Synthesis of Cyclopentyl Methyl Ether by Gas Phase Catalytic Reaction Using Strong Acid Ion Exchange Resin as a Catalyst —Study of Catalyst Deactivation Mechanism—

Synthesis of Cyclopentyl Methyl Ether by Gas Phase Catalytic Reaction Using Strong Acid Ion Exchange Resin as a Catalyst —Study of Catalyst Deactivation Mechanism—