Acidic Ion Exchange Resin Catalyst Research Articles

Two-Stage Conversion of Used Cooking Oil to Biodiesel Using Ion Exchange Resins as Catalysts

This study focuses on the development of a novel two-stage (esterification–transesterification) synthesis of biodiesel from used cooking oil (UCO) using ion exchange resins as catalysts. Esterification of the UCO has been conducted using various types of ion exchange resin catalysts. Purolite D5081, a hyper cross-linked resin, showed the best catalytic performance among all the catalysts investigated, with 92% of free fatty acid (FFA) conversion. The transesterification of pre-treated used cooking oil (P-UCO) was carried out sequentially using several acidic and basic ion exchange resin catalysts. In the screening process, the Diaion PA306s catalyst showed the best catalytic performance and was selected for the optimisation study. A triglyceride conversion of ca. 75% was recorded at the optimum reaction conditions (9% (w/w) catalyst loading, 328 K reaction temperature, 18:1 methanol to P-UCO feed mole ratio, and 350 rpm stirring speed). Furthermore, the reusability study of the Diaion PA306s catalyst gave a similar triglyceride conversion after a couple of cycles without losing its catalytic activity. A dry purification technique was found to give the lowest percentage of glycerides and glycerine content and, therefore, was chosen as the best biodiesel purification route.

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.

A Synthesis, Process Optimization, and Mechanism Investigation for the Formation of Polyoxymethylene Dimethyl Ethers

Polyoxymethylene dimethyl ethers (DMMn) are promising diesel additives. The synthesis of DMMn from methylal (DMM) and paraformaldehyde over the NKC-9 acidic ion-exchange resin catalyst was investigated. Many unrecyclable by-products such as methyl formate, dimethyl ether and formic acid were produced in the reaction. To increase the selectivity of the desired products DMM3‒6 and reduce the amount of unrecyclable by-products, the effects of reaction temperature, time, pressure and the molar ratio of the raw materials were evaluated through a series of single factor experiments. Experiments revealed that trace amount of water could suppress the formation of unrecyclable by-products, and the optimum initial water content (less than 2 wt%) was investigated. In addition, the synthetic process needs to go through the polyoxymethylene hemiformals intermediate stage, and then the DMMn were obtained when polyoxymethylene hemiformals reacted with methanol. Ultimately, a possible mechanism is proposed to describe the formation of DMMn from polyoxymethylene hemiformals in detail, in which it is revealed that the formation of carbocation intermediates is important in the reaction processes.

The oligomerization of high olefin containing hydrocarbon by-products to clean engine fuels

Nowadays it is an important issue in refineries to increase the gasoline/middle distillate flexibility because of the ever-changing engine fuel demands. One possible way is the oligomerization of light olefins (3–6 carbon atoms). The oligomerization of the C4-C6 olefin content of light FCC and more fractions with different composition was investigated on acidic ion exchange resin catalyst and premixed catalyst bed. The favourable application temperature of the ion exchange catalyst was 120–130 °C (P = 30 bar, LHSV = 1.0 h−1). The olefin conversion was also influenced by the composition of the feedstock. The best olefin conversion was achieved in the case of the feedstock with the highest olefin content (olefin conversion: 91.5%, C12+ ratio: 31.2%). Similar results were found with the application of premixed catalysts (B and C) in more oligomerization steps. Olefin conversion and selectivity was depended on the olefin and C12+ content of the feedstock. The total olefin conversion (related to the olefin content of the FCC naphtha feedstock) increased with each oligomerization steps, but it has to be investigated that how many steps could be economic. In the long term experiment (110 °C, 30 bar, 1.0 h−1) it was found that the conversion after 196 h decreased approx. 10% (compared with the initial value) but it was significantly lower after 60 h reaction time at 130 °C. The examined ion exchange resins - in the 100–120 °C temperature range - catalyze the oligomerization reactions for a long time, but an in-situ regeneration should be necessary.

The Oligomerization of Olefin Hydrocarbons in Light FCC Naphtha on Ion Exchange Resin Catalyst

In our experimental work our aim was the investigation of the possibility to convert olefin hydrocarbons of a light FCC naphtha fraction with oligomerization. In this framework, we studied the production possibilities of higher carbon number isoolefin rich motor fuel blending components, with oligomerization of the C4-C6 olefin content of the feedstock on water-containing acidic ion exchange resin catalysts. From the studied catalysts the ion exchange resin showed the highest oligomerization activity: the conversion of the olefins was 90.9 % and the share of oligomer products was 29.0 %. After hydrogenation of the C8-C16 isoolefin mixture, the octane number of gasoline product is around 100, the JET product has high energy content and low crystallization point, the cetane number of gas oil product is high and it has a good CFPP (cold filter plugging point). So with these two catalytic steps valuable products can be produced from light olefin-containing refinery by-products.

Activity Comparison of Acidic Resins in the Production of Valuable Glycerol Acetates

Abstract Acetates of glycerol have been produced in a heterogeneous reaction system using acidic ion-exchange resin catalysts; Amberlyst-15 (A-15), Amberlyst-16 (A-16), Amberlyst-36 (A-36), Amberlite-IR 120 (A-IR 120) and Relite-EXC8D (R-EXC8D). Effect of reaction temperature on glycerol conversion and product (mono, di and tri glycerol acetates) selectivities were investigated via reaction experiments conducted with glycerol to acetic acid initial molar ratio (G/Ac) of 1/6. Increase in glycerol conversion with an increase in temperature was observed for all catalysts. Among the catalysts investigated, R-EXC8D exhibited the highest activity in the temperature range of 95–150°C. Reaction was completed within a 25 minute short time period.

Response surface method and genetic algorithm assisted optimal synthesis of biodiesel from high free fatty acid sal oil (Shorea robusta) using ion-exchange resin at high temperature

In this study, response surface methodology (RSM) and genetic algorithm (GA) were used for the optimal synthesis of biodiesel from high free fatty acid sal oil using an acidic ion-exchange resin catalyst at high temperature and pressure. The conversion of sal oil to sal oil methyl ester (SOME) biodiesel was studied by varying catalyst loading, methanol–oil ratio, reaction time and temperature. The maximum trans-esterification temperature was set by the onset degradation temperature of sal oil, SOME biodiesel and catalyst. Analysis of variance was used to determine the significance of individual operating variables and their interacting effects on biodiesel yield. A quadratic polynomial model was obtained through multiple regression analysis using RSM to predict biodiesel yield. A multi-objective optimization problem was formulated involving conflicting objectives (i.e., maximization of biodiesel yield and minimization of trans-esterification time) and solved using non-dominated sorting genetic algorithm. Sets of non-dominated (equally good) Pareto solutions are obtained for the problem studied. The validity of optimal solutions obtained from RSM and GA was confirmed by the series of experimental results through quantification of sal oil, SOME biodiesel and free fatty acid by Fourier transformed infra red analysis. Activity of fresh and recycled resin catalyst was determined by ion-exchange capacity, scanning electron microscopy and measuring the biodiesel yield after several recycling of the catalyst. Finally, biodiesel was analyzed by the ASTM’s method.

Oligomerization of Light FCC Naphtha with Ion Exchange Resin Catalyst

There is a great importance to those processes which are producing from the lower value light hydrocarbons (C3–C6 paraffins and olefins) heavier and more valuable products (gasoline or middle distillate). In the hydrocarbon industry proven technologies already exist for the application of acidic ion exchange resin catalysts (e.g. synthesis of ethers). Our objective was to study the selectivity in oligomerization of a distillated FCC naphtha feedstock with ion exchange resins, in function of catalyst properties and operating conditions. In our experimental work we investigated the applicability of acidic ion exchange resins (5.46 and 4.98 eqH+kg−1 acidity; 31 and 52 m2g−1 surface area; 243 and 298 A pore size; respectively) alone and in premixed bed in case of 80–140 °C temperature, 15–40 bar pressure and 0.5–3.0 h−1 LHSV. In case of premixed catalyst bed both the olefin conversion (98–99 %) and the share of heavier oligomers (C12+ share: 40–49 %) increased compared to the share of C8–C11 oligomer products. The application of premixed bed was also investigated during a more than 600-h experiment.

Optimal synthesis of methyl ester of Sal oil (Shorea robusta) using ion-exchange resin catalyst

This paper deals with the synthesis of Sal oil methyl ester (SOME) biodiesel using Sal oil (Shorea robusta) and acidic ion-exchange resin catalyst (INDION-225 H). An experimental set-up was proposed for the synthesis of SOME biodiesel where esterification of free fatty acids and transesterification of glycerides of fatty acids took place simultaneously with continuous removal of water. Effects of methanol and catalyst loading were studied to maximize the conversion of Sal oil to SOME biodiesel. Biodiesel productivity was also tested using recycled catalyst and a constant yield of biodiesel was obtained for all the catalyst recycle experiments. Scanning electron microscope (SEM) study of recycled catalyst was carried out to check the morphology of the catalyst and the degradation of the catalyst after recycling. SEM analysis revealed that the catalyst activity remained unchanged after several recycles. In the proposed process, ion-exchange resin not only reduced catalyst consumption and effluent generation considerably but also enhanced the productivity of SOME biodiesel considerably by eliminating the steps of purification. Acid value was measured continuously to monitor the extent of biodiesel formation with reaction time. The yield of SOME biodiesel was measured after purification of the reaction mass and it was tested using ASTM’s standard methods of biodiesel testing. Finally, the properties of SOME biodiesel were compared with the petroleum-based diesel fuel.

The Oligomerisation of High Olefin Containing Hydrocarbon Fractions on Ion Exchange Resin Catalyst

Nowadays there is an increasingly important issue in refineries to increase the gasoline / middle distillate flexibility because of the ever-changing motor fuel demands. One possible way is to oligomerize light olefins (3-6 carbon atoms). There is a further advantage of the oligomerization technology that with the hydrogenation of the olefin-isoolefin mixture, formed as an intermediate product, high paraffin-isoparaffin containing products can be produced. In our experimental work we investigated the conversion possibilities with oligomerization of the C4-C6 olefin content of light FCC and more fractions with different composition on acidic ion exchange resin catalyst. The favourable application temperature of the ion exchange catalyst was 120-130 °C (P= 30 bar, LHSV= 1.0 h -1 ). The available olefin conversion was also influenced by the composition of the feedstock. We achieved the best olefin conversion in the case of the feedstock with highest olefin content (olefin conversion: 91.5 %, C12+ selectivity: 31.2 %).

Acetalization reaction between glycerol and n-butyraldehyde using an acidic ion exchange resin. Kinetic modelling

The acetalization reaction between glycerol and n-butyraldehyde using Amberlyst 47, an acidic ion exchange resin catalyst, was studied. These acetals can be obtained from renewable sources and seem to be good candidates for different applications such as oxygenated diesel additives. Amberlyst 47 acidic ion exchange showed good activity and stability after five consecutive cycles of reuse. Therefore, 100% of selectivity towards the formation of acetals and butyraldehyde conversions between 92% and 98% were obtained for different molar feed ratios of glycerol:aldehyde. For glycerol:aldehyde molar ratios lower than the stoichiometric one, 2,4,6-tripropyl-1,2,3-trioxane is also detected as product when glycerol is almost totally consumed. Moreover, a pseudo-homogeneous kinetic model able to explain the reaction mechanism was adjusted and the corresponding overall reaction order was determined. The addition of around 15wt% of water in the feed produces only a slight decrease in the butyraldehyde conversion, and it improves the mixing and transport properties of the reaction mixture.

Investigation of Production of Motor Fuel Components on Heterogeneous Catalyst with Oligomerization

The production of high isoparaffin containing motor fuels which comply with the changing needs and standards is a significant research area. Because of this type of hydrocarbons have numerous application, environmental and economical benefits. One of the possible productions for this type of hydrocarbons is oligomerization of light olefins followed by their hydrogenation. Based on our experimental results we established that the examined various catalytic systems containing acidic ion exchange resin catalyst are suitable for the flexible production of different motor fuel blending components (gasoline, middle distillate) with high conversion (92.4 %) and good selectivity in particular at the process parameters (T: 130 °C, P: 30 bar, LHSV: 1.0 h−1) we found favourable.

Selective epoxidation of natural triglycerides using acidic ion exchange resin as catalyst

ABSTRACTEpoxidation is a very useful reaction in organic synthesis. Due to the high reactivity of the epoxide group it can be used as an active intermediate for the synthesis of many high‐value products. Epoxides are commercial products and they have many industrial uses. Understanding the kinetics of epoxidation reactions can lead to production of value‐added products from locally available renewable natural resources. This research investigated the kinetics of epoxidation of cottonseed oil by peroxyacetic acid (PAA) generated in situ from hydrogen peroxide and glacial acetic acid (AA) in the presence of acidic ion exchange resin (AIER) catalysts, namely Amberlite IR‐120. The effect of several variables including temperature, stirring speed, catalyst loading, and particle size, concentration of hydrogen peroxide and AA on oxirane conversion was studied. A satisfactory level of oxirane conversion (greater than 65%) with high selectivity (greater than 90%) could be obtained if the epoxidation was carried out at optimum conditions, using in situ generated PAA. The Langmuir–Hinshelwood–Hougen–Watson (L–H–H–W) kinetic model approach has been adopted for the development of overall reaction rate equations, and the proposed kinetic model includes the major side reactions for the estimation of kinetic parameters. Kinetic parameters were estimated by fitting experimental data using a nonlinear regression method. From the estimated kinetic constants, the activation energy for the AIER catalysed epoxidation of cottonseed oil was found to be 10.1 kcal mol−1. Copyright © 2010 Curtin University of Technology and John Wiley & Sons, Ltd.

Investigation of the Oligomerization of Light Olefins on Ion Exchange Resin Catalyst

The requirements against the quality of motor fuels were rendered more rigorous in the past decade; the most important ones were the major reductions of the sulphur and aromatic content. Besides the changing of the regulation of the motor fuels, the harmful material emission of the Otto- and Diesel-engine built vehicles was also limited significantly. These effects make necessary the greater use of the environmentally friendly, relatively “clean burning”, technically heteroatom- and aromatic free, great n- and i-paraffinic containing blending components in the case of gasoline and diesel gas oils. During our experimental work we studied the possibilities of producing motor fuel blending components like these blending components with the oligomerization of the olefin content of light FCC-naphtha – assuming later industrial application – on Amberlyst-15 acidic ion exchange resin type catalyst. This topic is very important in a modern oil refinery, because different isoparaffin-rich motor fuel blending components can be produced (depending on the catalyst and the process parameters), and this technology can grow considerably the gasoline- and diesel gas oil flexibility of the oil refinery, too. The aim of our experiments was to produce motor fuel blending components with the oligomerization of C4-C6 olefins in light FCC-naphtha matrix. Working on the acidic ion exchange resin catalyst under different process parameters (T: 80–130 °C, P: 15–30 bar, LHSV: 0.5–3.0 h-1) we determined that in the studied process parameter range in preferable case (T: 100–110 °C, P: 25–30 bar, LHSV 0.5–1.0 h-1) the liquid product yield was: greater than 95%, the conversion of olefins: 90–92%, the selectivity of C8-C11: 70–76%, while the selectivity of C12+: 24–30%.

New biocomponents from glycerol

Glycerol is a by-product of biodiesel production, for which new uses are being sought. Etherification of glycerol with isobutene in liquid phase with acidic ion exchange resin catalyst gave five product ethers and, as a side reaction, isobutene reacted to C 8–C 16 hydrocarbons. The effect of the reaction conditions on the system was studied and conditions for optimal selectivity toward ethers were discovered near with isobutene/glycerol molar ratio of 3 at 80 °C. The conditions controlling the distribution of the product ethers were studied and it was found that the extent of the etherification reaction and thus the main ether products can be changed by varying the reaction conditions.

Esterification of formic acid, acrylic acid and methacrylic acid with cyclohexene in batch and distillation column reactors: ion-exchange resins as catalysts

Esterification of formic acid, acrylic acid and methacrylic acid with cyclohexene was carried out in the presence of cation-exchange resins as catalysts. Effect of various parameters, e.g. speed of agitation, catalyst particle size, catalyst loading, types of catalyst, temperature, mole ratio of the reactants, was studied to optimise the reaction conditions. The reaction of formic acid, with different concentrations in aqueous solutions, with cyclohexene was studied. Experiments were carried out in the presence of homogeneous catalyst, p-toluene sulphonic acid ( p-TSA), to compare results with the heterogeneous catalyst. A comparison of anhydrous esterification between acrylic acid and that of methacrylic acid with cyclohexene has been reported. The conversion of formic acid in aqueous solutions to cyclohexyl formate, by reaction with cyclohexene, in a distillation column reactor (DCR), packed with an acidic ion-exchange resin catalyst was studied; the effect of variables such as feed flow rate, molar ratio of reactants, amount of catalyst in the reboiler, concentration of formic acid, location of the feed point, etc., was studied. A comparison between the rate of esterification of formic acid with cyclohexene in batch mode and in distillation column reactor has been made. An attempt was also made for the selective esterification of formic acid with cyclohexene from a mixture of formic acid and acetic acid in a DCR.

Mechanism of 1-butene hydration over acidic zeolite and ion-exchange resin catalysts

Vapour-phase hydration of 1-butene at atmospheric pressure above 373 K shows similar features on both H-clinoptilolite and sulphonic acid ion-exchange resin: the initial reaction rate linearly increases with the partial pressure of 1 -butene and passes through a maximum as a function of water pressure. Kinetics was evaluated accordingly. A decrease in the 1-butene isomerization rate indicated that under hydration conditions more than 99.9% of the acidic sites are hydrated. For the hydration, however, hydroxonium ions are the active centres where an adsorbed water molecule reacts with gasphase 1-butene in the rate determining step. The equilibrated desorption of secondary butanol ends the reaction. The kinetic inhibition by butanol can be suppressed with water. Above ca. 0.2 bar water pressure inactive polyhydrated hydroxonium ions are formed.

Mechanism of 1-butene hydration over acidic zeolite and ion-exchange resin catalysts

Vapour-phase hydration of 1-butene at atmospheric pressure above 373 K shows similar features on both H-clinoptilolite and sulphonic acid ion-exchange resin: the initial reaction rate linearly increases with the partial pressure of 1 -butene and passes through a maximum as a function of water pressure. Kinetics was evaluated accordingly. A decrease in the 1-butene isomerization rate indicated that under hydration conditions more than 99.9% of the acidic sites are hydrated. For the hydration, however, hydroxonium ions are the active centres where an adsorbed water molecule reacts with gasphase 1-butene in the rate determining step. The equilibrated desorption of secondary butanol ends the reaction. The kinetic inhibition by butanol can be suppressed with water. Above ca. 0.2 bar water pressure inactive polyhydrated hydroxonium ions are formed.

Hydration of 2-methylbutenes on organic ion exchange resin catalysts

The course of the hydration of a mixture of 2-methyl-1-butene and 2-methyl-2-butene in dependence on the structure of strongly acidic styrene-divinylbenzene ion exchange resin catalysts has been studied. The most efficient catalysts turned out to be macroporous ones. The reaction rate increased with increasing temperature, while the amount of the product (2-methyl-2-butanol) in the equilibrium reaction mixture decreased. Similarly, the hydration was strongly affected by the water to alkene molar ratio in the starting reaction mixture. Modification of ion exchange resin catalysts with 1-butylamine did not affect course of the hydration in the case of gel type catalysts, while with macroporous resin catalysts the addition of amine up to 0.5% of the total catalyst exchange capacity showed activating effect.

Hydrolysis of Carbohydrates in the Presence of Hydrochloric Acid or Acidic Ion-exchange Resins

Abstract Potato amylose and sucrose were hydrolyzed in the presence of hydrochloric acid or acidic ion-exchange resin catalyst. In hydrolysis of amylose at 65°C, the efficiency of resin catalysts was negligibly small as compared with that of hydrochloric acid. In hydrolysis of sucrose at 50°C, the efficiency of resin catalysts was less than that of hydrochloric acid and different according to their sizes. The relation between the average radius and the rate constant was obtained in a broader range than ever.