Amount Of Tetraethyl Orthosilicate Research Articles

Matching the Cellulose/Silica Films Surface Properties for Design of Biomaterials That Modulate Extracellular Matrix.

The surface properties of composite films are important to know for many applications from the industrial domain to the medical domain. The physical and chemical characteristics of film/membrane surfaces are totally different from those of the bulk due to the surface segregation of the low surface energy components. Thus, the surfaces of cellulose acetate/silica composite films are analyzed in order to obtain information on the morphology, topography and wettability through atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and contact angle investigations. The studied composite films present different surface properties depending on the tetraethyl orthosilicate (TEOS) content from the casting solutions. Up to a content of 1.5 wt.% TEOS, the surface roughness and hydrophobicity increase, after which there is a decrease in these parameters. This behavior suggests that up to a critical amount of TEOS, the results are influenced by the morphology and topographical features, after which a major role seems to be played by surface chemistry—increasing the oxygenation surfaces. The morphological and chemical details and also the hydrophobicity/hydrophilicity characteristics are discussed in the attempt to design biological surfaces with optimal wettability properties and possibility of application in tissue engineering.

Nanocomposite hydrogels for melanoma skin cancer care and treatment: In-vitro drug delivery, drug release kinetics and anti-cancer activities

Malignant melanoma is a lethal human skin cancer that is not easily treatable through traditional medicines, surgeries, and therapies. Millions of cases are recorded annually to cure physiological skin defects by chemotherapy that causes several adverse effects and challenges. Moreover, pathogenic infections might aggravate infection with subsequent ulceration or cutaneous melanoma. Accordingly, we synthesized nanodrug by loading chemotherapeutic agent, Fluorouracil (5FU), onto the reduced graphene oxide (rGO). We then extracted arabinoxylan (ARX) from the husk of Plantago Ovata and functionalized it into carboxymethylarabinoxylan (CMARX) and loaded synthesized nanodrug. We have crosslinked CMARX/nanodrug with different amount of tetraethylorthosilicate (TEOS) to prepare nanocomposite hydrogel rGO-5FU-CMARX system for melanoma skin cancer care and treatment. These nanocomposite hydrogel systems rGO-5FU-CMARX have exhibited different physicochemical properties. These properties were analyzed through FTIR, SEM, water contact angle, swelling in different media (aqueous and PBS) and biodegradation in PBS media. The in-vitro activities, i.e., drug delivery via Franz diffusion, antibacterial against S. aureus and P. aeruginosa and the anticancer activities was performed against Uppsala 87 Malignant Glioma (U-87) cell lines. Moreover, rGO-5FU-CMARX nanocomposite hydrogels displayed different antimicrobial and anticancer activities based on different crosslinking. Hence, an inventive rGO-5FU-CMARX based nanocomposite hydrogel drug-delivery system was developed to treat malignant melanoma skin cancer after bacterial infections.

Preparation of Modified Silane Composite Emulsion and Its Effect on Surface Properties of Cement-Based Materials

A new type of waterproofing composite emulsion with high silane content and good economic efficiency was synthesized by sol synthesis. The effects of the amount and proportion of the compound emulsifier, amount of tetraethyl orthosilicate, and mixing time on the properties of the emulsifier were investigated. The optimum conditions for the synthesis of a tetraethyl orthosilicate/isobutyl triethoxysilane emulsion were determined. The composite emulsion was characterized by infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, and energy-dispersive spectrometry, along with a series of microscopic testing techniques. It was verified that the composite emulsion was coated on the surface of the paste to form a hydrophobic protective layer. The results show that the composite emulsion can achieve a permeability and impervious effect after coating the concrete material, and microhardness tests prove that the composite emulsion will not reduce the surface hardness of cement-based materials.

Catalytic Degradation of Polylactic Acid over Al2O3@SiO2 Core–Shell Catalysts

Al2O3@SiO2 core–shell catalysts were synthesized by sol–gel method. The core size’control was provided by using of polyethylene glycol (PEG) and glycerol. The shell thickness was optimized by using the different amount of tetraethylorthosilicate (TEOS). The formation of core and shell structures in catalysts was seen in high resolution transmission electron microscopy (HRTEM) images. In some catalysts, the use of PEG caused to formation of a more monodisperse core structure. The particle size of catalysts was observed in the range of 8–12 nm. The BET (Brunauer–Emmett–Teller) surface area and total pore volume of catalysts ranged 440–1014 m2/g and 1.28–2.57 cm3/g, respectively. In addition, pore diameter reached up to 25 nm. The use of PEG and glycerol improved textural properties. While BET surface area and total pore volume values decreased by the increase of TEOS amount, shell thickness increased a little. Fourier transform infrared (FTIR) spectrums of the pyridine adsorbed catalysts revealed the presence of Lewis and Bronsted acid sites in the catalysts. The catalysts were tested in the degradation of polylactic acid (PLA) by using thermogravimetric analysis (TGA) technique. TGA results showed the degradation temperature of PLA decreased from 353 to 321 °C in the presence of catalysts. Activation energy values were calculated using Flynn–Wall–Ozawa method. The activation energy was reduced from 337 to 199 kJ/mol. Pore structure, particle size and acidity of catalysts significantly affected the degradation performance.

Anti-corrosion non-isocyanate polyurethane polysiloxane organic/inorganic hybrid coatings

As people become more aware of the necessity and importance of environment protection and product safety, the environmentally friendly non-isocyanate polyurethane (NIPU) has received great attention. In this work, a series of NIPU anti-corrosion coatings were prepared by amine-terminated NIPU, tetraethyl orthosilicate (TEOS), and bisphenol A (BPA) epoxy. First, the BPA cyclic carbonate was synthesized from carbon dioxide and BPA epoxy resin. Then, the amine-terminated NIPU was synthesized from BPA cyclic carbonate and fatty acid amine. Next, the NIPU TEOS hybrid coatings were formulated by different amounts of TEOS. The anti-corrosion performance of NIPU TEOS hybrid coatings was evaluated by electrochemical impedance spectroscopy and salt spray. NIPU coating with 5 wt. % of TEOS showed the best anti-corrosion behavior while NIPU coating with 20 wt. % of TEOS exhibited the worst corrosion resistance. The resulting anti-corrosion difference was attributed to the organic/inorganic micro-phase separation, which was confirmed by scanning electron microscopy and energy dispersive X-ray spectroscopy. This study reveals the effect of TEOS on the anti-corrosion performance of environmentally friendly NIPU coatings.

New approaches for the development of cellulose acetate/tetraethyl orthosilicate composite membranes: Rheological and microstructural analysis

The rheological behavior of cellulose acetate (CA)/tetraethyl ortosilicate (TEOS) blends in tetrahydrofuran (THF), microstructural properties and thermal stability of the corresponding films were investigated in this work. The studied blends exhibit different behaviors depending on the amount of tetraethyl orthosilicate contained. Cellulose acetate pure solution present a Newtonian behavior on the entire shear rate domain, while by addition of TEOS a decrease in viscosity with increasing of shear rate is observed, as result of the polymer backbone disentanglement and orientation of the polymer chain in the flow direction during the rheological tests. On the other hand, for the CA/TEOS blends increasing of viscosity with increasing of TEOS content is a consequence of the two components possibility to form hydrogen and covalent bonds. Also, for a high content of TEOS a gel behavior, with storage modulus higher than loss modulus, was identified. Studies of infrared spectroscopy, atomic force microscopy and thermal stability confirm that, as TEOS content increases the number of interactions is supplemented, so that for a TEOS content that exceeds 2 wt% the process of film casting will be difficult. Thus, this study represents a first stage to identify the optimal compositions of the CA/TEOS mixtures that would favor the obtaining of uniform and homogeneous porous films with improved properties and suitable for use as membranes both in industrial and biomedical applications.

High permeation and antifouling polysulfone ultrafiltration membranes with in situ synthesized silica nanoparticles

Highly hydrophilic and fouling-resistant polysulfone (PSF)-silica based nanocomposite ultrafiltration membranes were prepared using a one-pot method by combining phase inversion and nanoparticle formation in one step. The membrane forming solution prepared by mixing different amounts of tetraethyl orthosilicate (TEOS) with PSF solution in N-methyl-2-pyrrolidone (NMP) was cast on non-woven support and immersed into an aqueous acidic bath for phase inversion and silica nanoparticle formation. The membrane morphologies, nanoparticles distribution, hydrophilicity, and charge nature were investigated using scanning electron microscopy, atomic force microscopy, transmission electron microscopy, and contact angle as well as zeta potential measurements. The water flux, protein adsorption, and rejection were assessed, showing its applicability in filtration and separation technologies. The silica nanoparticle-containing membranes exhibited superior water permeation, rejection, and antifouling performance as compared to the neat PSF membrane. An almost 5-fold decrease in protein adsorption and a 3-fold increase in pure water flux were recorded for the nanocomposite membrane prepared with 20 wt.% TEOS. The results reveal that the membrane properties depend on the concentration of silica nanoparticles, making it possible to achieve a good trade-off between permeation and rejection.

Synthesis of polystyrene@silica@organosilica hierarchical hybrid particles through seeded emulsion polymerization

We reported the synthesis of hierarchical polystyrene@silica@organosilica hybrid particles with different morphologies via seeded emulsion polymerization. Series of organosilica seeds with different core@shell morphologies were first synthesis through the same biphasic sol-gel methods incorporation with a Pickering process. For the Pickering process, tiny silica particles (15 nm) were first formed and then used to stabilize 3-(methacryloxy)propyl trimethoxy silane (γ-MPS) droplets. Various amount of tetraethyl orthosilicate (TEOS) was then delivered in to the aqueous solution carefully to form a biphasic system and formed seeds with different core@shell structures when the up layer disappeared. For the seeded emulsion polymerization, the virous morphologies of the seeds induced different surface hydrophilicity which lead to different monomer swelling process before polymerization, and further result in the different morphologies of the final hybrid particles. Hybrid particles with multi-pod core@shell, watermelon-like, worm-like and daisy-like morphologies were achieved in this work. These hybrid particles with soft organosilica inner core, hard silica interlayer and polymer shell may have important applications in coating, printing, sensors, drug encapsulation and many related materials science areas.

Influence of TEOS and MgO addition on slurry rheological, optical, and microstructure properties of YAG transparent ceramic

Stable dispersed slurries were prepared from a mixture of commercial Al2O3 and Y2O3 powders by the ball milling process. Ammonium poly meta acrylate (Dolapix CE64) as the dispersant and different amounts of tetraethyl orthosilicate (TEOS)+0.1 wt% MgO as the sintering aids were added to the slurries. The effects of TEOS and MgO addition on the fabrication of transparent polycrystalline YAG ceramics were investigated by slip casting and vacuum sintering. The results showed that almost all slurries containing TEOS and TEOS + MgO had a near-Newtonian behavior, but the slurry containing only MgO had shear thickening with a thixotropic behavior. Also, by increasing the amounts of TEOS, due to the creation of steric repulsion, the viscosity was decreased. In comparison, TEOS + MgO slurries had lower viscosity than the TEOS ones. This was due to both the release of more ethanol and MgO action as a dispersant agent among the particles of yttria and alumina. All samples were pure YAG phase. The maximum transmittance at 1064 nm (≈83%) was obtained for the sample of 0.5 wt% TEOS+0.1 wt% MgO. A nearly pore-free microstructure with high relative final density (99.99%), a narrow grain size distribution (2.5–7.5 μm), with the average grain size of 4.5 μm, was achieved in this sample.

Hydrothermal synthesis of nano-SnO2@SiO2 composites for lithium-ion battery anodes

SnO2-based lithium-ion batteries have low cost and high energy density, but their capacity fades rapidly during lithiation/delithiation due to phase aggregation and cracking. A modified hydrothermal method was developed to synthesize tin oxide doped with highly dispersed silicon oxide, sing SnCl4·5H2O and amounts of tetraethyl orthosilicate as the starting materials and NH3·H2O as PH regulator. Fine powders of tin oxide as active materials were doped with highly dispersed silicon oxide as inert materials in atomic or nano-meter scale. The microstructure, morphology and electrochemical performance of the mixtures were analyzed by X-ray diffraction, infra-red, scanning electron microscopy and electrochemical methods. Silicon oxide as matrix should be able to support the anode changes accompanied by the formation of lithium–tin alloys, thus an improvement of the cycle ability of the Li-ion battery would be expected. The electrochemical results showed that addition of silicon oxide reduces the irreversible capacity during the first discharge/charge cycle. The electrochemical performance indicates that amorphous silicon oxide is an appropriate matrix and these composites are good anode candidates for application in lithium-ion batteries.

Thermoluminescence (TL) response of silica nanoparticles subjected to 50 Gy gamma irradiation.

Thermoluminescence (TL) response of silica nanoparticles synthesized by the sol-gel method is presented here. Transmission electron microscopy (TEM) was used to find out the size and morphology of the pure silica nanoparticles. By using an appropriate amount of tetraethylorthosilicate, ethanol, deionized water and ammonia solution, silica samples were synthesized. To determine the best TL response of silica, samples were irradiated with 50Gy gamma rays. The effect of size dependency towards TL yield indicates that decreasing the particles’ size of silica, increases the TL yield.

Recycling of surfactant template in mesoporous MCM-41 synthesis

The recycling of surfactant template is investigated through the reuse of the surfactant template in the mesoporous MCM-41 synthesis process. In the synthesis of MCM-41, tetraethylorthosilicate (TEOS) solution in water was utilized as the silica source while hexadecyltrimethylammonium bromide (CTAB) solution in ethyl alcohol was used as a surfactant template. The synthesized gel is formed thoroughly by mixing the two solutions under acid conditions with a pH value of 0.5 for 1 hour and kept for crystallization for 48 hours. The as-synthesized MCM-41 powder is recovered by filtration while the filtrate (mother liquor) was then reused for the second synthesis cycle. The synthesis procedure was repeated till no further solid product was formed. The synthesized gel was not produced in the unifying solution in the fifth cycle of MCM-41 synthesis. The quality of the calcined MCM-41 powder produced in each synthesis cycle was evaluated by calculating the amount of MCM-41 produced and the surface area of the powder product. The result showed that 1.28, 0.37, 1.64, 1.90 and 0.037 g were obtained in the 1st, 2nd, 3rd, 4th and 5th synthesis cycle, respectively. The surface area of the powder produced was found to be 1170, 916, 728, and 508 m2/g for 1st, 2nd, 3rd and 4th respectively. The concentration of the surfactant template has reached value lower than the critical micelle concentration (CMC) and remained constant after the 4th cycle. There was no further formation of gel due to low availability in the interaction between silicate anions and surfactant cations when the amount of TEOS was fixed for every synthesis cycle.

FORMULATION OF HYBRID MEMBRANE LAYER BY USING PVA/CHITOSAN BLENDED POLYMERS ON POROUS POLYSULFONE SUPPORT, AND THE APPLICATION ON COPPER ION REMOVAL

In this study, a thin film composite membrane was fabricated by using hybrid membrane as the barrier layer and polysulfone membrane as base membrane. During the formulation of hybrid membrane, a polymer blend of polyvinyl alcohol with chitosan was chosen as organic polymer and it was cross-linked with tetraethylorthosilicate (TEOS), where sol gel method is used to prepare the hybrid membrane. Phase inversion method is used to prepare the base membrane. The aim of this study is to determine the optimum concentration of the polymer for porous support membrane as well as the concentration of chitosan and TEOS in the fabrication of the thin film composite. Four concentrations of polysulfone (PSF) solution was prepared (13wt%, 14wt%, 15wt% and 17wt %) and the optimum concentration was determined. For the hybrid membrane, concentration of chitosan solution was varied at1wt%, 2wt% and 3wt% with fixed concentration of polyvinyl alcohol (PVA) solution (10wt %). Results showed that 2wt% chitosan and 13 wt% PSF is sufficient to remove acceptable percentage of copper ion. For this purpose of identifying optimum amount of TEOS, pH of the feed copper ion solution was adjusted to three conditions (pH 3, 7, 10). Although, the percentage removal is highest at pH 10 but when dealing with natural integrated complexation method, pH 7 is found to be the optimum pH for the removal of copper ion. Besides that, 3 wt% TEOS in hybrid membrane has found to give a remarkable percentage removal of copper ion. Overall, a new formulation of thin film composite membrane show a great potential to compete with those commercial membrane in thin film composite membrane application especially separation process.

Preparation of silica micro spheres via a semibatch sol–gel method

Silica micro spheres could be obtained through a semibatch sol–gel process, which was carried out by adding a solution of tetraethyl orthosilicate in ethanol into a mixture batch of KCl, ethanol, NH3•H2O, and water. Compared with other methods the semibatch sol–gel method could produce micro size silica spheres with narrow size distribution. The influence of reaction factors to the size and size distribution of silica spheres were studied. K+ could help obtaining large size silica but also could reduce the charge shielding effect, which caused the collision of silica spheres. Water and NH3•H2O were necessary for the hydrolysis of tetraethyl orthosilicate. However, too much water could form thicker hydration shell around K+, and more NH3•H2O in mixture batch would increase number of the nuclei of the solution. When the consumption rate of active silanol for the growing of silica could not offset its formation rate, a small silica size, and broad size distribution would occour. Therefore, the amount of tetraethyl orthosilicate in the reaction and its adding rate should be careful controlled. It was also found that the reaction temperature and holding time, which is the time for stirring of solution after tetraethyl orthosilicate injection, had no significant influence on the particle size.

Experimental investigation into the compressive strength development of cemented paste backfill containing Nano-silica

This paper investigates the influence of Nano-silica (NS) addition on the consistency and compressive strength development of cemented paste backfill (CPB). Tetraethyl-Orthosilicate (TEOS) was used as the precursor of Nano-silica along with ether-based Polycarboxylate superplasticizer (PCS). Two binder types (Portland cement and Slag-cement) and different amounts of TEOS (0.7–14% by mass of binder) with and without PCS are examined for 3, 7, 14, and 28 days curing time. Uniaxial compression tests for unconfined compressive strength (UCS) determination, slump height measurement, changes in gravimetric water content, and differential thermogravimetric analysis (DTG) were used to assess the influence of NS and admixtures (TEOS-PCS) on CPB performance. The results of this experimental study indicate that the addition of approximately 5% TEOS along with 0.5% PCS (by mass of binder) provide the best compressive strengths that can also be anticipated through the higher amount of calcium silicate hydrate (CSH) on DTG curves. It is also noticeable that the positive influence of NS is more evident when the amount of binder was decreased. The addition of PCS to CPB containing NS improved both the consistency of the mixture and the compressive strength development of CPB.

Corrosion protection of chromium-coated steel by hybrid sol-gel coatings

Abstract The aim of this study was to investigate the effect of the amount of tetraethyl orthosilicate (TEOS) on the corrosion protection of chromium-coated steel (CCS) by poly(methyl methacrylate)- co -(trimethoxysilyl)propyl methacrylate (PMMA- co -TMSM) coatings in aerated and unstirred solutions containing 2 wt% NaCl and acetic acid, at pH around 3.5. The MMA/Si molar ratios in the hybrid materials were adjusted to 10, 3, and 1 by adding different amounts of TEOS, producing materials denoted PMMA-Sil-10, PMMA-Sil-3, and PMMA-Sil-1, respectively. Scanning electron microscopy (SEM) images showed that the PMMA-Sil-10 and PMMA-Sil-3 hybrid coatings were homogeneous. These hybrids were submitted to 21 days of submersion in the same solution used to perform the electrochemical measurements, and their structural profiles investigated. 29 Si NMR results showed that hydrolysis and condensation reactions took place during the immersion treatment and provided further reinforcement of the siloxane network, which could enhance protection against corrosion. Furthermore the synthesis method enabled the close control of the inorganic phase content of the PMMA-RSiO 3/2 hybrids. Electrochemical analysis demonstrated that the PMMA-Sil-3 coating remained on the metallic substrate for a prolonged period, providing high protection against corrosion due to the controlled TEOS content of the hybrid material.

New Bismaleimide-Silica Hybrid Materials: A Critical Assessment of Properties in Correlation with the Method of Synthesis

ABSTRACTNew hybrid materials have been prepared by sol–gel technique. They have been obtained from bismaleimide monomers either in reaction with N-(3-triethoxysilylpropyl)furan-2-carboxamide monomer, by a Diels–Alder reaction, or in reaction with (3-aminopropyl)triethoxysilane following a Michael addition reaction. The sol–gel process was conducted with or without adding different amounts of tetraethyl orthosilicate. The structures of the obtained compounds have been confirmed by proton nuclear magnetic resonance and Fourier transform infrared spectroscopy. A comparative study between Diels–Alder- and Michael addition-type products regarding their thermal and mechanical properties was also conducted for samples as obtained from synthesis. The thermoreversible character of the Diels–Alder hybrid materials has been demonstrated with the aids of differential scanning calorimetry and attenuated total reflectance Fourier transform infrared spectroscopy, the results from both methods being in good agreement with each other, and with literature data. The morphology of hybrid materials was studied by the atomic force microscopy, optical microscopy for three different stages: initial (24°C), at heating (150°C), and after cooling at 24°C, and scanning electron microscopy. All data confirmed the driving force for the dispersion of the Si-containing aggregates in the Michael addition series is the dynamic evolution of the sol–gel process, whereas the Diels–Alder series behavior is ruled by the thermoreversible character of the Diels–Alder cycloaddition.

Three-dimensional graphene nanosheets loaded with Si nanoparticles by in situ reduction of SiO2 for lithium ion batteries

The utilization of silicon based anode materials for lithium-ion batteries is hindered by their low intrinsic electronic conductivity, unstable cycling behavior and complex scalable synthesis of nano silicon. Herein, we propose a step-by-step synthesis route to fabricate three-dimensional (3D) graphene nanosheets loaded with Si nanoparticles for lithium ion batteries. For this purpose, silica is deposited on the surface of graphene oxide firstly through a hydrolysis process. After that, a further in situ magnesiothermic reduction is carried out. In an attempt to fine-tune the mass ratio of graphene and Si, different amount of tetraethyl orthosilicate was applied during the hydrolysis process. The 3D graphene as supporting sheets could not only provide position for the firmly attached Si nanoparticles but also enhance the electronic conductivity and accommodate large volume changes of Si nanoparticles. As a result, the properly designed Si@G-2 exhibits an excellent electrochemical performance and rate capability, showing capacity retention of 90.9% after 100 cycles at 1Ag−1 and specific capacity around 500mAhg−1 at 20Ag−1. This synthetic route demonstrates an efficient method for the controlled synthesis of graphene nanosheets loaded with Si nanoparticles with excellent electrochemical performance, which may facilitate its commercial applications.

Mechanical and thermal behaviour of bamboo flour-reinforced XLPE composites

In the present work, the influence of natural fillers (bamboo flour/BF) on crosslinked polyethylene (XLPE) has been discussed. The main difficulty for the preparation of the composites is to establish adhesion between hydrophilic natural fillers and hydrophobic matrix. Consequently, coupling agent (CA) as silane must be added to promote interface. In this work, different amounts of tetraethyl orthosilicate (TEOS) were used as coupling agent and SEM images allow us to control the quality of the interface. Differential scanning calorimetry (DSC) shows that the XLPE crystallinity is unmodified upon the introduction of BF. The absence of transcrystallinity is important for preserving the ductility of composites. The dynamic mechanical analyses (DMA) highlight an optimum of shear modulus for a TEOS content of 5 mass% (CA5). Above this amount, the mechanical properties are reduced. These results were confirmed by the SEM observations which highlighted the decrease in the interface between the XLPE and BF. Furthermore, neither the introduction of BF nor the treatment with TEOS exerts an influence on the relaxation temperature: there is no plasticization. The combination of DSC/DMA allows us to show that higher viscoelasticity favouring impact strength is observed in XLPE/BF CA5 composites.

Production of Light Olefins Through Catalytic Cracking of C5 Raffinate Over Surface-Modified ZSM-5 Catalyst.

Surface modification of phosphorous-containing porous ZSM-5 catalyst (P/C-ZSM5-Sil.(X)) was carried out by a chemical liquid deposition (CLD) method using tetraethyl orthosilicate (TEOS) as a silylation agent. Different amount of TEOS (X = 5, 10, 20, and 30 wt%) was introduced into P/C-ZSM5il.(X) catalysts for surface modification. The catalysts were used for the production of light olefins (ethylene and propylene) through catalytic cracking of C5 raffinate. It was found that external surface acidity of P/C-ZSM5-Sil.(X) catalysts significantly decreased with increasing TEOS content. In the catalytic reaction, both conversion of C5 raffinate and yield for light olefins showed volcano-shaped curves with respect to TEOS content. Among the catalysts tested, P/C-ZSM5-Sil.(20) catalyst exhibited the best catalytic performance in terms of conversion of C5 raffinate and yield for light olefins. Thus, an optimal TEOS content was required for CLD treatment to maximize light olefin production in the catalytic cracking of C5 raffinate over P/C-ZSM5-Sil.(X) catalysts.