Macroporous Cation Exchange Research Articles

Adsorption Mechanisms of CO2 on Macroporous Ion-Exchange Resin Organic Amine Composite Materials by the Density Functional Theory.

The adsorption mechanisms of CO2 on macroporous cation exchange resin (MCER), D001 ion-exchange resin, and macroporous ion-exchange resin organic amine composite materials (MCER-DEA and D001-PEI) were studied by density functional theory (DFT). The adsorption energies and Mulliken atomic charges in the adsorption process were analyzed, indicating that CO2 on MCER and D001 were physisorbed. The adsorption heat of the adsorption process of MCER-DEA and D001-PEI was calculated by the Monte Carlo method, and it was found that the adsorption process of CO2 by MCER-DEA and D001-PEI was both physical adsorption and chemical adsorption. Besides, the chemical adsorption mechanism of CO2 by MCER-DEA and D001-PEI was investigated by analyzing the free energy barrier and the Gibbs free energy change of the involved chemical reactions and the results showed that the free energy barrier required for MCER-DEA to generate zwitterion was 26.23 kcal/mol, which is 1.74 times that of D001-PEI (15.04 kcal/mol); meanwhile, the free energy barriers of the deprotonation process of zwitterions in MCER-DEA and D001-PEI were 16.23 and 9.89 kcal/mol, respectively, indicating that D001-PEI chemically adsorbs CO2 and requires more energy than MCER-DEA chemical adsorption of CO2. D001-PEI is more conducive to the chemical adsorption of CO2. In addition, H2O molecules were incorporated on the polymer models to study the influence of humidity on the CO2 adsorption mechanism. The analysis revealed that the adsorption of CO2 slowed under humid conditions.

Samarium(III) Removal by Weak Acid Exchanger Amberlite IRC-50 in (H+) and (Na+) Forms

Adsorption of samarium(III) on a weakly macroporous cation exchanger Amberlite IRC-50 (H+) and (Na+) forms is studied as a function of the initial pH of the aqueous solution, time and temperature, initial samarium(III) ion concentration, and the amount of resin at a fixed temperature (20 ± 1 °C). The concentration range was between 0.1–5 mmol/L, the pH range was between 1.8 and 10.5; the stirring time was between 2 and 60 min; and the amount of resin was between 0.025 and 0.15 g. Both the film and particle diffusion equations are applied to explain the kinetic data. The rate constant values for samarium(III) adsorption were calculated for both film and particle diffusion processes. It is observed to follow the order (Na+) > (H+). Temperature is found to have an insignificant effect on both diffusional processes. Various thermodynamic parameters (ΔH°, ΔS°, and ΔG°) from samarium(III) exchange on the resin were calculated. The optimum conditions were found to be a concentration of 1 mmol/L, pH of 9.3, stirring time of 20 and 5 min for Amberlite IRC-50 (H+) and (Na+) forms, respectively, and 0.15 g of resin. The equilibrium extraction of samarium was 22.2 mg/g for Amberlite IRC-50 (H+) and 21.9 mg/g for Amberlite IRC-50 (Na+) at an initial concentration of 1 mmol/L. The results obtained show that the Amberlite IRC-50 weak cationexchange resin performed well for the removal and recovery of samarium(III). The optimization procedure provides access to industrial-scale Sm(III) removal processing.

Effects of Addition of Lanthanum and Zinc Oxides on the Biological Properties of TiO2-SiO2-P2O5/CaO on Ion Exchange Resin for Bone Implantation.

The spherical materials TiO2-SiO2-P2O5/CaO, TiO2-SiO2-P2O5/La2O3, and TiO2-SiO2-P2O5/ZnO deposited on the Tokem-250 cation exchanger have been synthesized with an alcoholic solution by the sol-gel method. The macroporous cation exchanger Tokem-250, which has high Ca2+, Zn2+, and La3+ ion selectivity, was used in the present study. This material has the ability to precipitate and mineralize calcium phosphates on its surface in biological media, since it has high porosity, a homogeneous structure with a uniform variation of elements, and the presence of active centers (Si4+, Ti4+) on the surface. The effect of lanthanum and zinc additives on biological properties has been studied. It was established that accumulation of Ca2+ and Mg2+ occurs faster on the surface of TiO2-SiO2-P2O5/ZnO in the SBF (simulated body fluid) model solution, showing higher reaction capacity. The amount of calcium and phosphorus ions on the surface of sample TiO2-SiO2-P2O5/La2O3 is greater due to the ability of lanthanum to coordinate a large number of ions (lanthanum coordination number is 10). The presence of zinc ions in the system causes the partial hemoglobin release from erythrocytes into the supernatant fluid. The samples with lanthanum ions reduce the amount of protein in plasma after incubation, which has a positive effect on the practical application.

Preparation of CuO loaded cation exchange resin composites and its degradation of polyacrylamide aqueous solution

Macroporous cation exchange resins (CER) were used as carriers, and CuO loaded cation exchange resin composites was successfully prepared under thermostatic oscillation and hydrothermal conditions. The results showed that the as-prepared composites exhibited obvious shell-core structure. The different amounts of NaOH affected the micro morphology of CuO on the surface and in the internal pores of the resin, and also affected the percentage content of Cu element. XRD characterization clearly revealed that the products were monoclinic crystal system CuO species with a grain size of about 16 nm. The highest degradation rate of polyacrylamide (PAM) by CuO@IER-1g reached 81.94%, after 6 cycles CuO@CER-1g has still good photocatalytic activity, and the decrease in degradation rate was the combined effect from the adsorption of ion exchange resins and the electron-hole pairs formed by CuO and a series of free radical transfer reactions under ultraviolet light. This study has important theoretical basis and practical significance for enriching ion exchange theory, developing the photocatalytic industry, and purifying the environment.

Adsorption differences and mechanism of chitooligosaccharides with specific degree of polymerization on macroporous resins with different functional groups

Ion exchange resins are promising materials for separating chitooligosaccharides (COSs) with different degrees of polymerization (DP). The adsorbent functional groups significantly determine the interactions with COSs and affect their adsorption and separation efficiency. This study investigated the adsorption behaviors of COSs on macroporous cation exchange resins with different functional groups to clarify the functional group effect on the adsorption of COSs with different DP, which can also help to provide a theoretical basis for the selection of separation medium and optimization of the separation technics of COSs. The results showed that the adsorption of COSs on sulfonic-acid type resin DX-10 and carboxylic-acid type resin DC-10 were favorable, and the adsorption isotherms were in accord with the Sips model. Adsorption thermodynamics showed that temperature had opposite effects on the two resins' equilibrium adsorption capacity of COSs. The diffusion coefficient of COSs on DX-10 resin was greater, and the affinity gap between COSs on DX-10 resin was larger than that of DC-10 resin, which is beneficial for improving the separation resolution of COSs. In contrast, the interaction energy between COSs with high DP and DC-10 resin was weaker compared with DX-10, which made the elution of COSs with high DP easier.

Fluoride removal by hybrid cation exchanger impregnated with hydrated Al(III) oxide nanoparticles (HCIX-Al) with novel closed-loop recyclable regeneration system

A high concentrations of fluoride (F-) in groundwater limits drinking water supplies and results in fluorosis for hundreds of millions of people globally. A novel F- selective adsorbent (HCIX-Al) with a closed-loop regeneration system was developed, characterized, and assessed for its effectiveness in F- removal using both synthetic and natural groundwater. The system used an inexpensive polymeric macroporous cation exchanger doped with hydrous aluminum oxide (HAlO) nanoparticles. The HAlO nanoparticles were loaded into the matrix of the polymer phase by ion-exchange reactions between Al3+ and Ca2+ ions that bind with sulfonic acid functional groups of the cation exchangers. Hydrogen ions were generated in-situ during the HAlO formation process, creating acidic conditions inside the polymeric phase, which significantly increased F- sorption capacity (maximum sorption capacity = 5.75 mg/g at pH 7.5). While most other aluminum oxide-based F- selective sorbents suffer from low F- removal capacity at neutral to alkaline pH of typical groundwater, the HCIX-Al exhibited high F- sorption capacity even using alkaline (pH 8.5) groundwater. The treated water had a pH greater than 6.5 and non-detectable levels of aluminum (detection limit 0.002 mg/L), which complies with drinking water regulations. The HCIX-Al material can be reused by conditioning the exhausted material with a closed-loop regeneration chemical containing a recyclable 12% AlCl3 solution. The F- was precipitated from the regeneration system as CaF2 using lime at pH 11. This material, including a novel regeneration scheme, offered high F- removal capacity, cost-effectiveness, and provided a sustainable defluoridation process.

Preparation of macroporous ion-exchange resin organic amine composite material by using waste plastics and its application in CO2 capture

ABSTRACT Two new types of solid adsorption material (macroporous cation exchange resin (MCER) and macroporous ion-exchange resin organic amine composite material (MCER-DEA)) were prepared from waste television plastics outer shell (WTPS) and used to capture CO2 in flue gas from coal-fired power plants. The results showed that the CO2 adsorption capacity of MCER-DEA was 2.87 mmol/g, while MCER was 1.87 mmol/g. The preparation mechanism and action mechanism of MCER and MCER-DEA was studied by Fourier transform infrared and quantum chemical calculations. The results showed that the electrophilic substitution occurs in between an H atom of meta position on the benzene ring and H2SO4. The electron energy of MCER-DEA was calculated to be 1.14 ev, indicating these MCERs formed acid–base coordination with diethanolamine (DEA). Besides, the electron energy of between MCER and CO2 was 0.27 ev, and the interaction force was dominated by hydrogen bonds. The electron energy of the MCER-DEA and CO2 was 3.02 ev, and the interaction force was mainly controlled by coordination bonds. It indicated that MCER and CO2 were primarily based on physical adsorption, while MCER-DEA and CO2 were mainly based on chemisorption adsorption. Adsorption kinetics studies showed that internal diffusion was a rate-controlling step.

Metastable nano-zirconium phosphate inside gel-type ion exchanger for enhanced removal of heavy metals

Nanotechnology has provided a new opportunity for water decontamination from trace heavy metals, yet the relatively poor acidic stability remains a major obstacle for the nano-adsorbents, given that acidic treatment is frequently used to regenerate the heavy metal-saturated adsorbents. Zirconium phosphate (ZrP) is very promising for water treatment due to its absolute insoluble nature, though it interacts with heavy metals mainly through the non-specific electrostatic attraction. Herein, we prepared the ultrafine ZrP (~3.9 nm) inside the commercially available gel-type cation exchanger (N001), i.e., the sulfonated poly(styrene-co-divinylbenzene) bead. The resultant nanocomposite ZrP@N001 contained the amorphous nanoparticles (NPs) with metastable γ-ZrP structure as the main phase, unlike the layered α-ZrP formed inside the macroporous cation exchanger D001 (referred to as ZrP@D001). As a result, ZrP@N001 could selectively adsorb heavy metals through inner-sphere coordination, possessing a much stronger adsorption affinity than ZrP@D001, as confirmed by XPS analysis. In both batch and column assays on the Pb(II)-polluted water, ZrP@N001 exhibited superior adsorption performance over ZrP@D001. After adsorption, the exhausted ZrP@N001 was fully refreshed by acidic treatment for a 5-cyclic adsorption-regeneration run with constant removal efficiencies. This study may open a door for the rational design of highly efficient water purifiers for heavy metal control.

Role of configurational flexibility on the adsorption kinetics of bivalent bispecific antibodies on porous cation exchange resins

The adsorption kinetics of a monoclonal antibody (mAb) used as a reference and of bivalent bispecific antibodies (BiSAb) on a macroporous cation exchanger is studied experimentally by examining the transient patterns of bound protein within the particles using confocal microscopy for a range of protein concentrations, buffer concentrations and pH, and temperatures. The mAb adsorption kinetics is controlled by pore diffusion and conforms to the classical shrinking core model. While the mAb adsorption rate increases with temperature, the ratio of effective and free solution diffusivity, De /D0, remains constant and has a value of 0.20. The BiSAb's structure is comprised of scFv domains that are genetically fused to a framework IgG through flexible peptide linkers which results in conformational flexibility leading to multiple binding forms with varying affinity for the adsorbent surface. As a result, adsorption of the BiSAbs shows complex patterns of total bound protein within the particles. These BiSAb adsorption patterns are influenced by buffer ionic strength, pH, and temperature in unique ways. Sharper intraparticle profiles are observed for conditions where the binding strength is greater (lower buffer concentration and/or pH) or when the protein is chemically crosslinked to restrict configurational flexibility. Temperature affects the BiSAb pore diffusivity as well as the interconversion kinetics. While the effects of temperature on BiSAb transport are also described by a constant De /D0 = 0.15, the temperature also affects the rate of interconversion between binding forms leading to faster equilibration at higher temperatures. A phenomenological model indicates that the interplay of pore diffusion and adsorption with the kinetically limited interconversion between binding forms is responsible for the experimental trends.

Preparative ion exchange purification of capreomycin from fermentation broth produced by Streptomyces capreolus

Capreomycin (CMN) is a second-line aminoglycoside antibiotic for treating multi-drug resistant tuberculosis. Produced as a complex broth in microbial bioreactors, the downstream purification of CMN traditionally requires multiple steps. Current work aims to purify CMN as mixed isomers in a single step by preparative macroporous cation-exchange chromatography in >98% purity in >90% yield. Selection of the adsorbent best suited for CMN purification was guided by modeling the molecular interactions, followed by wet-lab static and dynamic adsorption studies that validated the simulation results. Among the evaluated adsorbents (both weak and strong cation resins), the weak cationic Macro-Prep CM showed a favorable combination of selective binding and elution of CMN. Solute loading and elution conditions were further optimized to produce the desired quality of CMN. This single-step method was integrated with a continuous simulated bed reverse-phase desalting chromatography to produce 99% pure salt-free CMN. The proposed method provided productivity of about 2 g product/L resin/h of CMN on Macro-Prep CM; and 0.7 g product/L adsorbent/h on SMB. The study provides for a robust and scalable process for the industrial-scale production of purified capreomycin.

Solid-Liquid Extraction of Uranium from Nitrate Medium using Macroporous Cation Exchange Resin; Kinetics and Thermodynamics Studies

Solid-Liquid Extraction of Uranium from Nitrate Medium using Macroporous Cation Exchange Resin; Kinetics and Thermodynamics Studies

A facile modification of cation exchange resin by nano-sized goethite for enhanced Cr(VI) removal from water

ABSTRACT A novel macroporous strong acidic cation exchange resin (D001) modified by nano-sized goethite (nFeOOH@D001) was fabricated by using a facile ethanol dispersion and impregnation method, and its efficiency for Cr(VI) removal was tested thereafter. Due to the dispersing effect of ethanol, FeOOH particles of 20–150 nm were coated on the D001 surfaces. The nFeOOH@D001 obtained a Cr(VI) removal efficiency and capacity of 80.2% and 7.4 mg/g respectively, 5 times and 8 times higher than that of the pristine D001. The Cr(VI) removal by nFeOOH@D001 followed the pseudo second-order kinetics and the Langmuir adsorption model. Column experiments also demonstrated that the nFeOOH@D001 exhibited a much better ability to remove Cr(VI) as compared to the D001. Additionally, the nFeOOH@D001 showed a potential for reusability and renewability. The adsorbed nFeOOH@D001 could be easily desorbed by 0.1 M acetic acid and a reuse efficiency of 92.7% could be maintained after 4 desorption–adsorption cycles. The used nFeOOH@D001 could be eluted by 0.1 M HCl to remove nFeOOH, and the renewed D001 could be recoated by nFeOOH and achieved a regeneration rate of 97.8% for Cr(VI) removal. The above results indicated that nano-sized goethite modification is a promising method to endow D001 with the ability to remove Cr(VI) from water.

Adsorptive-Oxidative Removal of Sulfides from Water by MnO2-Loaded Carboxylic Cation Exchangers.

Hybrid ion exchangers (HIX) containing manganese(IV) oxide (MnO2) based on macroporous and gel-type carboxylic cation exchangers as supporting materials were obtained. The hybrid materials were characterized using scanning electron microscopy with energy dispersive spectrometry (SEM/EDS), Fourier transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD) and nitrogen adsorption isotherms at 77 K and mercury porosimetry. HIX with introduced MnO2 (20.0–32.8 wt% Mn) were tested for removal of dissolved sulfides from anoxic aqueous solutions with 100–500 mg S2−/dm3 concentrations. The process proceeded effortlessly at pH 10–13 despite unfavorable electrostatic interactions of the reactants. The highest exhibited sorption capacity was 144.3 ± 7.1 mg S2−/g. Approximately 65% of dissolved sulfides were oxidized to S2O32− ions and repelled from HIX structure. On average, 13% of sulfide removal products were adsorbed by the MnO2 surface. The impact of MnO2 load and the ionic form of HIX functional groups on removal of sulfides and resulting products was examined. The mechanism of the process is suggested.

Recovery of Lanthanum(III) and Nickel(II) Ions from Acidic Solutions by the Highly Effective Ion Exchanger.

The recovery of La(III) and Ni(II) ions by a macroporous cation exchanger in sodium form (Lewatit Monoplus SP112) has been studied in batch experiments under varying HNO3 concentrations (0.2–2.0 mol/dm3), La(III) and Ni(II) concentrations (25–200 mg/dm3), phase contact time (1–360 min), temperature (293–333 K), and resin mass (0.1–0.5 g). The experimental data revealed that the sorption process was dependent on all parameters used. The maximum sorption capacities were found at CHNO3 = 0.2 mol/dm3, m = 0.1 g, and T = 333 K. The kinetic data indicate that the sorption followed the pseudo-second order and film diffusion models. The sorption equilibrium time was reached at approximately 30 and 60 min for La(III) and Ni(II) ions, respectively. The equilibrium isotherm data were best fitted with the Langmuir model. The maximum monolayer capacities of Lewatit Monoplus SP112 were equal to 95.34 and 60.81 mg/g for La(III) and Ni(II) ions, respectively. The thermodynamic parameters showed that the sorption process was endothermic and spontaneous. Moreover, dynamic experiments were performed using the columns set. The resin regeneration was made using HCl and HNO3 solutions, and the desorption results exhibited effective regeneration. The ATR/FT-IR and XPS spectroscopy results indicated that the La(III) and Ni(II) ions were coordinated with the sulfonate groups.

Resin loaded palladium nanoparticle catalyst, characterization and application in –C–C– coupling reaction

Macroporous ion-exchange resins were used to immobilize palladium (Pd) metal in order to produce nanoparticle catalysts. The complexation of palladium acetate and the following reduction with NaBH4 resulting Pd nanoparticles are loaded on to DIANION™ PK228 macroporous cation exchange resins. Palladium loading was characterized by inductively coupled plasma-atomic emission spectroscopy, field emission scanning electron microscope/energy-dispersive X-ray spectrometry, BET (Brunauer–Emmett–Teller) and HR-TEM. Palladium nanoparticles are loaded on to DIANION™ PK228 macroporous cation exchange resin which shows and excellent catalytic activity for Suzuki–Miyaura cross coupling reaction. Furthermore, the catalyst can be recycled without significant loss of its catalytic activity up to ten times.

An efficient procedure for preparing high-purity pingyangmycin and boanmycin from Streptomyces verticillus var. pingyangensis fermentation broth via macroporous cation-exchange resin and subsequent reversed-phase preparative chromatography

Pingyangmycin (PYM) and boanmycin (BAM), two individual components of bleomycin (bleomycin A5 and bleomycin A6), are glycopeptide antitumor antibiotics. An efficient procedure for the preparation of PYM and BAM from Streptomyces verticillus var. pingyangensis fermentation broth using macroporous cation-exchange (MCE) resin followed by medium-pressure preparative liquid chromatography (MPLC) based on monodisperse poly(styrene-co-divinylbenzene) (p(st-dvb)) microspheres was investigated in this paper. Nine frequently used MCE resins were screened by static adsorption and desorption to enrich PYM and BAM fromthe fermentation broth, and D157 resin was found to be the most effective. After one run of column-based dynamic adsorption and desorption, the contents of PYM and BAM were increased by factors of 13.8 and 12.1 with recovery yields of 84.21% and 81.47%, respectively. The enriched samples were subjected to MPLC with columns prepacked with the PolyRP 10-300 microspheres. The operational parameters of the MPLC, including the stationary phase and mobile phase compositions, sample/stationary phase ratio, sample loading scale and flow rate, were screened and optimized. The results showed that the separation and purification for PYM and BAM by MPLC were dramatically improved with a mobile phase modifier of 0.15 mol/L ammonium chloride aqueoussolution, a flow rate of 10 mL/min and a sample/stationary phase ratio of 1.0:100 (m/v, g/mL), and PYM and BAM with purities of more than 98.65% and 99.12% were obtained, respectively. The total recoveries of PYM and BAM reached 75.38% and 70.31%. The separation and purification method is simple, efficient, energy-saving, environmentally friendly and suitable for the large-scale preparation of high-purity PYM and BAM from Streptomyces verticillus var. pingyangensis fermentation broth.

Nanosized Iron Oxide Uniformly Distributed on 3D Carbon Nanosheets: Efficient Adsorbent for Methylene Blue

Magnetic carbon materials as adsorbents for dye removing have attracted increasing attention because of their magnetic separation feature. However, the immobilization of large magnetic particles on a carbon matrix greatly decreases the available sites for adsorption, resulting in a low adsorption capacity. The synthesis of magnetic carbon materials as adsorbents for dye adsorption with high adsorption capacity remains challenging. Herein, porous carbon (PC) was firstly synthesized through the calcination of macroporous acrylic type cation exchange resin. The as-prepared PC was applied as a matrix to deposit nano-sized Fe3O4 nanoparticles (MPC) via a facile one-pot solvothermal strategy. The nano-sized Fe3O4 nanoparticles (5.19 nm in diameter) are uniformly distributed on the PC surface. The MPC possesses an exceptional performance for methylene blue removal (qe = 214.4 mg g−1) at room temperature, outperforming most previous magnetic carbon adsorbents. The large surface area of the MPC originated from the combined advantages of PC and nano-sized Fe3O4 must be ascribed to the high performance of MPC composite toward methylene blue adsorption.

Kinetic modeling of catalytic esterification of non-edible macauba pulp oil using macroporous cation exchange resin

Conversion of non-edible oils through heterogeneous catalysis and their kinetic aspects are essential in order to produce economically viable biodiesel. Especially for oils containing high Free Fatty Acids (FFA) content since those cannot be viably converted through homogenous catalysis. Herein, the heterogeneous catalytic esterification kinetics of macauba pulp acid oil was exploited. The reaction tests were conducted in a stirred batch reactor with ethanol, and a cation exchange resin (Purolite® CT275)as a catalyst. The reaction kinetics was modeled based on a pseudo-homogeneous (PH) model of second order, showing good agreement with the experimental data acquired under different reaction conditions. The reaction progress was monitored by validated HPLC and GC methods. The internal and external mass transfer resistances were evaluated, and show that the rate limiting step is the surface reaction. To assess the catalyst stability, scanning electron microscopy was performed on both fresh and spent (after 10 reaction cycles) catalysts; reuse of catalyst was conducted without further treatment. The catalyst recycling demonstrates good performance where 85% of its performance was retained, and the SEM images show that the materials were structurally stable. Because the Pseudo-Homogeneous model properly described the kinetic aspects of the esterification process it was possible to estimate thermodynamic parameters by using the Arrhenius plot. The activation energy of the forward reaction was determined as 44.0 kJ/mol, while for the reverse reaction was 11.7 kJ/mol. Therefore, the kinetic and thermodynamic descriptions along with the catalyst stability upon several cycles without any further treatment reflect the viability of these resins for industrial application in the energy sector. Furthermore, combining these features with the low cost of macauba pulp acid oil, we conclude that the process is suitable for scaling up studies.

Continuous biosynthesis of geranyl butyrate in a circulating fluidized bed reactor

The continuous synthesis of geranyl butyrate in organic solvent was studied. The Candida rugosa lipase(CRL) was firstly immobilized on weak-acidic macroporous cation exchange resin D151. The batch experiments indicated that the adequate acid/alcohol molar ratio was 1:1.5 and the reaction time was 3.5–4 h. Then the continuous synthesis was realized with immobilized Candida rugosa lipase in a circulating fluidized bed reactor(CFBR). A stable ester yield of 77% was achieved under optimal conditions: enzyme loading 8 g, expansion ratio 1.6, feed flow rate 0.07 ml/min and butyric acid concentration 75 mmol/l. The results provide the basis for the scale-up of the process.

Studies on free fatty acid esterification of used cooking oil: investigation on the performance of sulphonated cation exchange resins

ABSTRACTUsed cooking oil (UCO) is one of the potential substitutes for conventional biodiesel feedstock. In this study, different types of macroporous cation exchange resins, namely RCP160M, RCP145H, PK228LH, PK216LH, PK208LH, SK104H and SK1BH, were used as catalysts in the UCO esterification process. These resins were characterised using Fourier transform infrared spectroscopy (FT-IR), nitrogen physisorption, scanning electron microscopy (SEM), an elemental analyser (CHNS), titration and a particle size distribution (PSD) analyser to determine their physicochemical properties. These catalysts were screened and RCP160M resin was found to give the best catalytic performance. RCP160M was used in subsequent studies focusing on the effect of different esterification variables. A conversion rate of 95% of free fatty acid (FFA) was achieved at the optimum condition with catalyst loading of 4 wt. %, reaction temperature of 60°C, and methanol-to-oil mass ratio of 18:1. RCP160M shows great potential as a catalyst in the biodiesel pre-treatment process as it outperformed the other catalysts and yielded maximum FFA conversion. This may be attributed to its higher specific surface area and total pore volume. The kinetic results revealed that the experimental data was best fitted to the Eley-Rideal model (Case II) with the activation energy of 37.2 kJ mol−1.