HZSM-5 Research Articles

The production of debrominated aromatics via the catalytic pyrolysis of flexible printed circuit boards

Pyrolysis is an environmental technology for the proper treatment of electronic waste (e-waste) for the production of fuel. However, the presence of brominated compounds in pyrolysis oil makes its commercialization difficult. In this study, various types of zeolites, HY (30), HZSM-5 (30), HZSM-5 (50), HZSM-5 (280), and basic metal oxides (MgO and CaO) were used for the pyrolysis of flexible printed circuit boards (FPCBs) for the first time to produce bromine-free oil. A higher production efficiency of debrominated aromatic hydrocarbons, primarily benzene, toluene, ethylbenzene, xylenes (BTEXs), and naphthalene with zeolites, was achieved over basic metal oxides. The use of HZSM-5 (HZ) (30) increased the amount of benzene (an area of 31.5 × 107) and toluene (an area of 17.6 × 107), and a high debromination efficiency was observed for basic metal oxides owing to the strong affinity of halides toward the Ca2+ and Mg2+ ions. Among the BTEXs, benzene (an area of 31.5 × 107) and toluene (an area of 17.6 × 107) were obtained as highly selective monoaromatics in the presence of the catalyst HZ (30). CaO and HZ (30) were effective for debromination and aromatic production, respectively. The in-situ CaO/ex-situ HZ (30) combination revealed ∼ 100% debromination efficiency; however, the total aromatic hydrocarbon production was higher on the in-situ HZ (30)/ex-situ CaO with ∼ 77.5% debromination efficiency. Meanwhile, the in-situ HZ (30)/ex-situ CaO configuration could achieve ∼ 100% debromination efficiency by increasing the amount of CaO to 7 times to feed.

Synthesis of hierarchical HZSM-5 utilizing natural cellulose as templates for promoted production of aromatic hydrocarbons in the catalytic pyrolysis of biomass

Templating agents were created by utilizing several methods to handle natural cellulose (bagasse), and they were successfully used to treat HZSM-5 to introduce extra mesopores. In addition, the hierarchical HZSM-5 was employed in the catalytic pyrolysis of biomass to produce hydrocarbon fuels. The hydroxyl content in the templating agent could be promoted via hydrothermal and ultrasound-assisted treatment, improving their performance as templates to produce mesopores. The cellulose content in the templating agents was effectively boosted via hydrothermal-assisted treatment, whereas their relative crystallinity was improved by ultrasound assistance. The formation of mesopores was promoted with the increased cellulose content in the templating agents, and the catalytic performance in upgrading pyrolysis gas for aromatic hydrocarbons could be significantly improved. Higher relative crystallinity was advantageous for enhancing the stability of the templating agent in the catalyst synthesis system, and the formation of pore structures of the catalyst was promoted. Among all catalysts synthesized, catalysts synthesized by hydrothermal-assisted treatment (Cat-H(X)) presented the highest specific surface area and average pore size of 397.60 m2/g and 4.53 nm, which were about 1.41 and 1.98 times of commercial HZSM-5 (H-Z). The highest yield of BTX obtained with Cat-H(X) was 8.7 wt%, 1.81 times that obtained with H-Z.

Reduction of supported GaN and its application in methane conversion

The reduction of supported GaN using amorphous SiO2, silicalite-1 (S1), and HZSM-5 (HZ) as the carriers was investigated and tested for methane conversion to acetonitrile (ACN). Ammonia nitridation was used to synthesize GaN samples. The highest ammonia and ACN productivities (433 and 383 μmol/g, respectively) were obtained by using 5 wt% GaN on HZ (5GaN/HZ). The N–Ga interaction of 5GaN/HZ was discovered to be weakened due to the presence of a neighboring Brønsted acid. The oxidation state of gallium was reduced during methane conversion, implying the loss of nitrogen from GaN. The decreased activity could be rejuvenated by a renitridation step. The GaN surface structures, including the adsorption surface, 11¯0, and the side surfaces, (001), (110), (111), and 111¯, were calculated via first-principles calculations. Among them, the (001) side surface of GaN was likely to be the origin of mobile nitrogen, which is important in the conversion of methane to ACN.

Enhanced Catalytic Activity of Modified ZSM-5 Towards Glucose Isomerization to Fructose.

The present study focuses on generating mesopores within H-ZSM-5 (H-Z) zeolite via desilication and dealumination to incorporate Lewis acidic metal, such as Sn, into the framework (Sn4 ZS180 A15 ) to catalyse glucose isomerisation. Sn4 ZS180 A15 possesses enhanced surface area (457 m2 g-1 ), mesopore volume (0.585 cm3 g-1 ) and a high weak-medium to strong acidic sites ratio, compared to parent H-Z (395 m2 g-1 ; 0.174 cm3 g-1 ). DRS-UV-Vis and XPS results corroborate Sn incorporation into the framework of Sn4 ZS180 A15 , based on the absorbance peak around 200-220 nm and peaks appearing at 495.8 and 487.4 eV, respectively. Sn4 ZS180 A15 exhibits higher catalytic activity towards glucose isomerisation in ethanol-water at 110 °C, yielding 44.2 % fructose with 80.0 % selectivity. Conversely, the parent H-Z afforded negligible glucose conversion with a fructose yield of <1 % under identical conditions. Moreover, Sn-incorporated on dealuminated (Sn4 ZS0 A15 ) and desilicated (Sn4 ZS180 A0 ) catalysts give a low yield of fructose (7-10 %), signifying the requirement of the desilication-dealumination process before incorporating Sn into the framework.

Enhancing selectivity of aromatics in direct conversion of syngas over K/FeMn and HZSM-5 bifunctional catalysts

Mixed Fischer-Tropsch synthesis (FTS) catalysts and HZSM-5 (HZ5) have received attention as bifunctional catalysts that directly convert syngas into value-added aromatic monomers. However, both low selectivity of aromatics and severe deactivation remain challenges. Here we report a simple method for obtaining selective aromatics from syngas by tuning the distribution of hydrocarbon (HC) intermediates on K/FeMn. We prepared K/FeMn catalysts with a varying Mn/(Fe+Mn) wt% to demonstrate the effect of the HC distribution as intermediates of aromatization on HZ5. The C6-C10 distribution was increased by addition of up to 60 wt% of Mn promoter due to the improved dispersion of Fe7C3 and alkyl insertion of MnO. At 340 °C under 20 bar, 97.2% CO conversion and 39.8% aromatics selectivity were achieved by using a physically mixed catalyst of K/FeMn with Mn/(Fe+Mn) 60 wt% and HZ5 with an optimization of the FTS-derived C6-C10 olefin yield as efficient intermediates in Syngas to Aromatics (STA).

Bio-gasoline and bio-naphtha production from catalytic cracking of linseed oil methyl ester over iron- and zinc-modified HZSM-5 and γ-Al2O3 catalysts in a fixed double-beds reactor

This study investigates the catalytic cracking of linseed oil methyl ester in producing bio-naphtha and bio-gasoline fuels. The process was conducted over two beds of catalysts, including HZSM-5 (HZ) and γ-alumina (AL), in a continuous reactor. The support catalysts were modified by zinc and iron metals with various loadings (4 wt% and 8 wt%) through the incipient wetness impregnation method and characterized by XRD, XRF, FESEM-EDS, N2 adsorption-desorption, and NH3-TPD analyses. These analyses demonstrated that the existence of metals altered the textural properties and the acid site distribution of support catalysts. The experiments were carried out at the Cat. Ratio (mass ratio of AL catalyst to total mass of AL & HZ catalysts) = 0.75, WHSV = 3 h−1, T = 475 °C, P = 1 bara under N2 atmosphere. The aim was to discuss the synergistic effect of using two modified catalyst beds in production of bio-naphtha and bio-gasoline. With this respect, the general factorial design approach was employed for the statistical evaluation of the bio-naphtha and bio-gasoline production yields. The results revealed that bio-naphtha could be produced with the yield of 42.3 wt% over the double catalyst beds comprising 4ZnHZ and AL. By using 4FeHZ & AL in series, 39.0 wt% yield of bio-naphtha could be achieved. According to the bio-gasoline yield, Fe and Zn loading value of 4 wt% is the most suitable, i.e. 90.3 wt% yield on 4FeHZ-4FeAL, and 89.5 wt% yield on 4ZnHZ-4ZnAL can be obtained.

Efficient and selective catalytic pyrolysis of cellulose to monocyclic aromatic hydrocarbons over Zn-containing HZSM-5

A series of Zn-containing HZSM-5 (HZ5) with hierarchical pores (xZn(DS)) were obtained by adding different amounts of Zn(NO3)2 solution in a hydrothermal synthesis process. The performances of xZn(DS) in catalytic reforming of cellulose pyrolysis volatiles were investigated at 500 °C. The results showed that the addition of Zn during synthesis increased in the total pore volume of xZn(DS) and reduced the content of strong acid sites, and introduced new weak acid sites. The Zn species were highly dispersed inside the zeolite, and enhanced the accessibility of acid sites, so that the yields of light aromatic hydrocarbons and monocyclic aromatic hydrocarbons (MAHs) over 0.7Zn(DS) (The molar ratio of ZnO/Al2O3 in the synthesis process of xZn(DS) was 0.7) were higher than those over S-HZ5 (Zn was not added in the synthesis process) and commercial HZ5. Compared with S-HZ5, the yield of MAHs over 0.7Zn(DS) increased from 92.8 to 114.1 mg/g and the coke yield decreased by 2.9%. The selectivity of MAHs over 0.7Zn(DS) was 87.7%, which was 5.3% higher than that over S-HZ5. Simultaneously, the increase in mesopores of xZn(DS) accelerated the mass transfer process, shortened the diffusion path and improved the anti-coking performance of the catalysts. In addition, this study also proposed a possible mechanism for the catalyst to adjust the distribution of aromatic products and provided a new idea for promoting the selective production of MAHs for the pyrolysis of cellulose.

Boosted production of aromatics by catalyzing upgrade pyrolysis vapors from lignite over Sn-Ga/HZSM‑5 catalysts

A multifunctional catalyst of Ga-Sn anchored on hierarchical HZSM‑5 (Sn-Ga/AT0.2H5) was investigated in catalytic reforming of lignite pyrolysis volatile. A strong synergy was observed between Ga and Sn for the production of aromatics. The addition of Ga into AT0.2H5 remarkably promoted the selectivity of aromatics including benzene, toluene, ethylbenzene, xylene and naphthalene (BTEXN) compared to pure HZSM-5 (H5). The BTEXN yields increased to 24.1 mg/g over monometallic 5%Ga/AT0.2H5, in which the benzene yield was attained to 14.8 mg/g. With the introduction of Sn, the yield of aromatics was further improved to 25.1 mg/g. An explanation of this scenario was that introduced active metals could enhance the transformation of cyclic intermediates into aromatics and H5 support with an appropriate concentration of the acid sites provided acidic protons for aromatization. Additionally, the bimetallic Sn-Ga/AT0.2H5 exhibited higher stability with the yield of BTEXN maintained over 22 mg/g after three recycle experiments, which offered an efficient strategy to prolong the catalyst lifetime.

High-Impact Promotional Effect of Mo Impregnation on Aluminum-Rich and Alkali-Treated Hierarchical Zeolite Catalysts on Methanol Aromatization.

A systematic change of HZSM-5 (HZ5) as a catalyst of the methanol to aromatics (MTA) reaction was undertaken by employing a fixed-bed tubular-type reactor under ambient pressure, applying a weight hourly space velocity (WHSV) of 2 h–1 at 375 °C, as the first report on the application of low-Si/Al-ratio alkaline-[Mo,Na]-HZSM-5 in the MTA process. To characterize the surface and textural properties of the catalysts, powder X-ray diffraction (PXRD), nitrogen adsorption/desorption, temperature-programmed desorption of ammonia (NH3-TPD), pyridine-infrared spectroscopy (Py-IR), thermogravimetric analysis (TGA), and energy-dispersive X-ray (EDX) methods were employed. Gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) measurements demonstrated a selectivity of up to 86 wt % (65.7 wt % for benzene, toluene, and xylene (BTX)) over 2[Mo]HZ5. NH3-TPD and Py-IR results indicated a sensible decrease of strong acid sites on the impregnated samples, while the surface analyses revealed the highest Lewis acid sites (LAS) together with the largest mesopore surface area for 2[Mo]alk-HZ5, supporting the migration of Mo species to the bulk of the catalysts. Mo impregnation had a minor effect on the observed coke formation in the promoted catalyst.

Sulfation-acidified HZSM-5 catalyst for in-situ catalytic conversion of lignite pyrolysis volatiles to light aromatics

This study elucidated the effects of crystalline structure and acidity of sulfation-acidified HZSM-5 (HZ5) catalyst on the reaction routes and light aromatics (LAs) distribution during catalytic fast pyrolysis (CFP) of Shengli lignite. HZ5 modified by (NH4)2SO4 (AS), (NH4)2S2O8 (APS), and H2SO4 (HS) were applied to conduct CFP of lignite in a drop tube quartz reactor at 600 °C. The results indicated that the yield of LAs, especially monocyclic aromatics, increased considerably as the increase of pore size and midstrength acid sites (the decrease of non-shape selective acid sites) caused by sulfation-acidification modification. Among all the modified catalysts, 0.5AS-550 (modified with 0.5 mol/L AS and calcined at 550 °C) showed a better prospect than APS and HS modification in promoting the formation of LAs (the maximum yield of 28.8 mg/g). Meanwhile, the elimination of non-shape selective acid sites and regeneration of mesoporous reduced coke yield by 0.6% compared to HZ5. In addition, the possible reaction routes and catalytic mechanism over sulfation-acidified HZ5 catalysts were proposed to describe the formation of LAs.

Enhancement of Bio-based para-Xylene Selectivity in Catalytic Fast Pyrolysis of Cellulose Using a Surface-modified Mg/P/HZSM-5 Catalyst

With the growing consumption of oil, the production of p-xylene(PX) from renewable biomass has gained significant attention recently. This work demonstrated that cellulose, a main component in lignocellulosic biomass, was directly converted into PX over the Mg/P surface-modified zeolites. The catalysts modified by the incorporation of P2O5 and MgO into HZSM-5(HZ) promoted the isomerization of m-/o-xylenes to p-xylene. The PX selectivity was greatly enhanced using the modified zeolites due to the deactivation of external surface and the adjustment of pore entrance. In addition, the addition of methanol to cellulose was beneficial to increase the selectivity of xylenes due to the alkylation reactions and the Diels-Alder reactions between cellulose-derived furans and methanol-derived olefins. The highest PX yield of 10.7%(molar fraction) with a high PX selectivity in xylenes(97.1%) was obtained over the 10%Mg/5%P/HZ catalyst. The reaction pathway for the formation of p-xylene was addressed according to the study of the key reactions and the characterization of catalysts.

Nitrogen migration mechanism and formation of aromatics during catalytic fast pyrolysis of sewage sludge over metal-loaded HZSM-5

In order to effectively improve the quality of bio-oil from catalytic pyrolysis (CFP) of sewage sludge (SS) and to produce aromatic-rich bio-oil, the evolution mechanisms of nitrogen and formation of aromatics during CFP of SS over metal-loaded HZSM-5 (HZ) were investigated in depth. The results show that the presence of metals caused the slight decrease in oil-C (carbon in bio-oil) yield and the increase in gas yield and total carbon yield of aromatics. Ni-loaded HZ has a better performance than Co-loaded one in improving the carbon yield of aromatics, while the maximum yield of 11.2% was obtained over 0.5Ni-HZ. Metal-loaded HZ promoted the formation of monocyclic aromatics rather than polycyclic aromatics and Ni significantly enhanced the selectivity of benzene. With the addition of Ni and Co, more nitrogen was released as NH3 or fixed in solids. NH3 yield increased by raising the metal loading, and the highest NH3 yield of 36.8% was obtained over 3.0Ni-HZ. Ni and Co promoted the cracking reactions during CFP to generate more H radicals, which have advantages to the ring-opening of N-containing heterocycles in SS to produce aromatics and NH3. A possible catalytic mechanism of CFP of SS over metal loaded HZ was proposed in this study.

Methanol aromatization over CrZn-modified HZSM-5 catalysts

HZSM-5 (HZ) zeolite co-modified with Zn and second promoters (Zr, Ce, Mo and Cr) was synthesized and the aromatization of methanol over the modified HZ in a fixed-bed reactor was investigated. The results of catalytic tests revealed that the methanol conversion and yield of benzene, toluene, and xylene (BTX) over the Cr, Zn comodification HZ (CrZn/HZ) were higher than that over ZrZn/HZ, CeZn/HZ, and MoZn/HZ. The catalysts were characterized by XRD, SEM, TEM, XPS, N2 isothermal adsorption-desorption and NH3-TPD. The results suggest that Zn species exist in two forms in the HZ zeolite. One is ZnO particle, the other one is ZnOH+, which significantly improveds the yield of BTX. Furthermore, the Cr species on the external surface promoted the dispersion of ZnO, increased the amount of ZnOH+, which further improved the yield of BTX. In addition, the optimal Cr2Zn1/HZ catalyst exhibited better catalytic performance and prolonged lifetime of reaction.

Effect of Metal Active Sites on the Product Distribution over Composite Catalysts in the Direct Synthesis of Aromatics from Syngas

The conversion of syngas to aromatics over composite catalysts, comprising a mixture of Fe2O3-SiO2 and Nb-/Ni- modified HZSM-5 (HZ), CuO-ZnO-Al2O3 (CZA) and Nb-/Ni- modified HZ, and a mixture of above two kinds of metal oxides and Ni-HZ, were investigated at 330 °C, 4 MPa and H2:CO = 2:1. Catalysts were characterized to analyze the properties. Fe2O3-SiO2/modified-HZ had the high selectivity of BTX, while CuO-ZnO-Al2O3/modified-HZ had the high selectivity of durene. Fe-CZA/Ni-HZ exhibited higher selectivity of trimethylbenzene (triMB) than both Fe/Ni-HZ and CZA/Ni-HZ, lower selectivity of BTX and tetramethylbenzene (tetraMB), compared with Fe/Ni-HZ and CZA/Ni-HZ, respectively. Reaction pathways were speculated to illustrate the diverse distribution of aromatics. The incorporation of Nb and Ni on the parent HZSM-5 increased the selectivity of aromatics due to their various acidity. The highest selectivity of BTX was obtained over Fe/Ni-HZ and the highest selectivity of durene was achieved over CZA/Nb-Ni-HZ.

Catalytic pyrolysis of waste tire to produce valuable aromatic hydrocarbons: An analytical Py-GC/MS study

Pyrolysis of waste tire with HY, HZSM-5 (HZ) and purified attapulgite (PA) catalysts to produce valuable aromatic hydrocarbons has been carried out in a Pyrolyzer- Gas Chromatograph/Mass Spectrum (Py-GC/MS) reactor. Likewise, d-limonene and polybutadiene rubber (BR), which played important roles in the pyrolysis process of waste tire, has also been pyrolyzed in the Py-GC/MS reactor with these catalysts. Based on the product distribution, the catalytic pyrolysis mechanisms of d-limonene were proposed, while those of BR were extended. With these mechanisms, the catalytic pyrolysis characteristics of waste tire could be explained reasonably. Results showed that HY promoted a dramatic increase of aromatics from pyrolysis of d-limonene and BR, leading to the considerable growth of aromatics in the degraded products of waste tire. The shape selectivity of HZ to mono-cyclic aromatics performed effectively in the pyrolysis of BR, yet it exhibited a weak performance in the pyrolysis of d-limonene. As a result, upon the catalytic pyrolysis of waste tire, HZ was inferior to HY in the aromatization ability. However, the selectivity of HZ to BTXE (benzene, toluene, xylene and ethylbenzene) was superior to that of HY. PA performed a weaker catalytic ability in promoting the production of aromatics during the pyrolysis of d-limonene, BR and waste tire.

Syngas conversion beyond chemical equilibrium by in situ bimolecular reaction

An in situ bimolecular reaction, in which syngas is fed with toluene as a secondary reactant (hereafter Tol in situ methylation), was studied over bifunctional catalysts comprised of methanol synthesis catalyst and H-ZSM-5 in a fixed-bed down-flow reactor at 460 psig. When physically mixed with H-ZSM-5 to form bifunctional catalysts, CrZ_HZ (Cr2O3/ZnO + HZSM-5) catalyst showed much higher activity than CZA_HZ (CuO/ZnO/Al2O3 + H-ZSM-5) in the Tol in situ methylation, while CrZ catalyst exhibited substantially lower activity than CZA in methanol synthesis. CO conversion to methanol in the Tol in situ methylation was estimated by Bz in situ methylation. The CO conversion to methanol was calculated to be in the range of 11–27 %, while that in methanol synthesis over CrZ was about 5 % at most due to chemical equilibrium limitation. By employing a silicalite-coated H-ZSM-5 (Sil/HZ) in bifunctional catalyst, xylene selectivity and para-xylene yield were much improved in the Tol in situ methylation.

Catalytic cracking of 1-butene to propylene by Ag modified HZSM-5

Silver modified HZSM-5 (AgHZ) zeolite catalysts were prepared by ion exchange method and their catalytic properties in the 1-butene cracking reaction were measured. The catalysts were characterized by infrared spectroscopy with pyridine adsorption (Py-IR), N2 adsorption and X-ray diffraction (XRD). The effects of Ag loading and steaming treatment on catalytic performances were studied. It is found that the activity of HZSM-5 (HZ) catalyst significantly decreases with the steaming time, whereas AgHZ catalysts show stable activity in the steaming time of 24–48h and their activities increase with the Ag loading. When the steaming time is 24–48h, the yield of propylene over HZ catalyst significantly decreases, whereas it is stable over AgHZ catalysts. The AgHZ catalysts with Ag loadings of 0.28%–0.43% (by mass) show similar propylene yields (~30%), which are higher than that over the AgHZ catalyst with a Ag loading of 0.55% (by mass). These results indicate that the steam-treated AgHZ catalysts with optimum Ag loadings have higher yield of propylene and are more stable than the steam-treated HZ catalyst. The regeneration stability measurement in butene cracking also shows that the AgHZ catalyst steam-treated under a suitable condition has better stability than the HZ catalyst.

Synthesis of Non‐Toxic Triethyl Citrate Plasticizer by Esterification of Renewable Citric Acid Using Modified Zeolite

Triethyl citrate (TEC), a non‐toxic plasticizer, was synthesized by esterification of renewable citric acid (CA, from entire waste of oranges) with ethanol over modified H‐ZSM‐5 (HZ‐5) zeolite. Different micro–meso composites (M‐HZ‐5) with varying crystallinities were prepared by alkaline treatment of HZ‐5. M‐HZ‐50.6 (87% crystallinity) was observed to be a potential and environmentally benign catalyst with 96% CA conversion, 64% TEC selectivity (61.44% TEC yield), and a reusability of six cycles. The probable catalytic mechanism of esterification was also proposed.

Production of Xylenes from Toluene and 1,2,4‐Trimethylbenzene over ZSM‐5 and Mordenite Catalysts in a Fluidized‐Bed Reactor

AbstractThe production of various xylenes from toluene, heavy aromatics such as 1,2,4‐trimethylbenzene (1,2,4‐TMB) and their mixture was investigated over H‐ZSM‐5 (H‐Z), H‐mordenite (H‐M) and a dual zeolitic catalyst comprising ZSM‐5 and mordenite (H‐ZM). The experiments were conducted in a riser‐simulator reactor under different operating conditions to study the effect of temperature, reaction time and feed composition on conversion and product yields. At 400 °C, the conversion of toluene over the three catalysts yielded mainly benzene and xylenes with maximum conversion at 25 % and a xylene yield of 12.5 wt % over the H‐M catalyst. The transformation of 1,2,4‐TMB doubled the conversion level and xylene yield and suppressed benzene formation. However, a considerable portion of the 1,2,4‐TMB feed was isomerized into 1,2,3‐TMB and 1,3,5‐TMB accompanied by the formation of tetramethylbenzenes (TeMBs). The conversion of an equimolar mixture of toluene and 1,2,4‐TMB over the three catalysts resulted in higher toluene conversion and double xylene yield in comparison with 1,2,4‐TMB alone. The advantage of using a dual zeolitic catalyst was observed at an equimolar feed of toluene and 1,2,4‐TMB, exhibiting maximum toluene conversion, higher xylene yield and the formation of lower levels of undesirable products.

A Comparative Study of the Esterification Activity of Nanosized H-ZSM-5 with Commercial H-ZSM-5 and H-Beta Zeolite

Nanosized H-ZSM-5 (NZ) was synthesized and characterized for BET surface area, pore volume, pore size distribution, and acidity. The catalyst was tested toward esterification of cyclohexanol with acetic acid under autogenous pressure condition and the activity was compared with that of commercial H-ZSM-5 (HZ) and H-beta zeolite (BZ). Nanosized H-ZSM-5 was found to be more active than commercial H-ZSM-5, whereas beta zeolite showed remarkably higher activity than H-ZSM-5 and nanosized H-ZSM-5. The catalysts exhibited the increasing activity in the order of HZ < NZ < BZ. The superior activity of BZ was found to be due to higher Brønsted acidity and higher surface area. The maximum conversion was found to be 72% for H-beta zeolite, whereas nanosized H-ZSM-5 gave 69% conversion in esterification reaction.