PDF Publication Title:
Text from PDF Page: 002
ChemEngineering 2019, 3, 35 2 of 11 acetate, phenyl acetyl chloride, phenyl propionic, phenylpropionyl chloride [3], acetyl chloride [4] and acetic anhydride [5–7] has been widely reported. The catalyst activity and selectivity of zeolite H-Beta, H-ZSM-5, H-Y, and NH4-Y catalysts in the acylation reaction of anisole with acetic anhydride were compared by Freese et al. [5]. They reported a lower catalytic activity of H-ZSM-5 compared to H-Y and H-Beta catalysts with only 14% of conversion; this is due to smaller intersection channels in ZSM-5 [8]. Zeolites are microporous crystalline aluminosilicates that have a similar composition to the clay minerals. However, they are different in their well-defined three-dimensional microporous structures. Silicon, aluminum, and oxygen are arranged in a regular structure of tetrahedral units of [SiO4]− and [AlO4]−, forming a framework with regular pores. The pores are in the form of channels, tunnels, or cavities with a diameter of around 0.1–2 nm running through the material [9]. Mesoporous zeolites, consisting of microporous structure and intra-crystalline mesoporosity, show improved catalytic activities in many organic reactions because of their enhanced reactants and products diffusion from/to active sites in microporous via the mesoporous frameworks [10]. Such materials help to overcome the limitation of microporous zeolites pore size and therefore allow large molecules to diffuse through [11]. The synthesis of mesoporous ZSM-5 via a dissolution process include the re-assembling of amorphous silica directed by surfactant molecules simultaneously; the re-assembling of the total dissolved structure of zeolite around surfactant molecules has also been reported [12]. In the presence of long-chain alkyl ammonium surfactants, the dissolved silicates accumulate within surfactant molecules to make micelles and re-precipitate onto the surface of parent spheres surface to convert amorphous silica into mesoporous silica during the hydrothermal reaction [13]. The synthesis of mesoporous ZSM-5 zeolites has been extensively studied using a silylated polyethylenimine as a mesoporous-directing agent and polymers are the most widely used templates, including long-chain organosilicates, amphiphilic surfactants [14], polyvinyl butyral [15], CTAB, F127, and P123 [16]. The lesser reactive Al sites support the maintenance of the zeolite framework in an alkaline medium, while the Si atoms dissolve, rendering more open structures. Desilication in comparison to dealumination provides more controllable mesoporosity and also preserves the Brønsted acidity [17]. The study of ZSM-5 and silicalite-treated alkali with sodium hydroxide aqueous solutions at high concentrations showed that Si atoms could be removed with no change in the crystallinity of the zeolites. Therefore, the present work is focused on the synthesis of ZSM-5 and the treatment of synthesized zeolite with an alkali solution as well as several different surfactant templates to form a uniform-sized mesoporous material without deterioration of crystallinity of the parent zeolite structure. The catalytic activity of untreated and treated zeolite catalysts was also studied in a batch reactor at different temperatures. 2. Material and Methods 2.1. Materials Cetyl trimethyl ammonium bromide (CTAB) was purchased from Fisher Scientific whilst tetra propyl ammonium hydroxide (TPAOH), sodium hydroxide (NaOH), ammonium nitrate (NH4NO3), anisole and propionic anhydride were obtained from Merck. NH4-ZSM-5 (Si/Al = 23) was purchased from Zeolyst International. 2.2. Synthesis of Mesoporous ZSM-5 Catalyst NH4-ZSM-5 zeolite (0.176 g) was dispersed in deionized water (20 g) using an ultrasonic bath. TPAOH (0.2 g) was separately dissolved in a solution consisting of NaOH (0.312 g) and deionized water (20 g). The prepared solution was appropriately mixed using an ultrasonic bath for 5 min and then put in a Teflon-lined autoclave. The hydrothermal treatment of the obtained solution was performed at 100 ◦C for 24 h. Further, the treated product was washed a few times using deionizedPDF Image | Synthesis of Uniform Mesoporous Zeolite ZSM-5 Catalyst
PDF Search Title:
Synthesis of Uniform Mesoporous Zeolite ZSM-5 CatalystOriginal File Name Searched:
ChemEngineering-03-00035.pdfDIY PDF Search: Google It | Yahoo | Bing
NFT (Non Fungible Token): Buy our tech, design, development or system NFT and become part of our tech NFT network... More Info
IT XR Project Redstone NFT Available for Sale: NFT for high tech turbine design with one part 3D printed counter-rotating energy turbine. Be part of the future with this NFT. Can be bought and sold but only one design NFT exists. Royalties go to the developer (Infinity) to keep enhancing design and applications... More Info
Infinity Turbine IT XR Project Redstone Design: NFT for sale... NFT for high tech turbine design with one part 3D printed counter-rotating energy turbine. Includes all rights to this turbine design, including license for Fluid Handling Block I and II for the turbine assembly and housing. The NFT includes the blueprints (cad/cam), revenue streams, and all future development of the IT XR Project Redstone... More Info
Infinity Turbine ROT Radial Outflow Turbine 24 Design and Worldwide Rights: NFT for sale... NFT for the ROT 24 energy turbine. Be part of the future with this NFT. This design can be bought and sold but only one design NFT exists. You may manufacture the unit, or get the revenues from its sale from Infinity Turbine. Royalties go to the developer (Infinity) to keep enhancing design and applications... More Info
Infinity Supercritical CO2 10 Liter Extractor Design and Worldwide Rights: The Infinity Supercritical 10L CO2 extractor is for botanical oil extraction, which is rich in terpenes and can produce shelf ready full spectrum oil. With over 5 years of development, this industry leader mature extractor machine has been sold since 2015 and is part of many profitable businesses. The process can also be used for electrowinning, e-waste recycling, and lithium battery recycling, gold mining electronic wastes, precious metals. CO2 can also be used in a reverse fuel cell with nafion to make a gas-to-liquids fuel, such as methanol, ethanol and butanol or ethylene. Supercritical CO2 has also been used for treating nafion to make it more effective catalyst. This NFT is for the purchase of worldwide rights which includes the design. More Info
NFT (Non Fungible Token): Buy our tech, design, development or system NFT and become part of our tech NFT network... More Info
Infinity Turbine Products: Special for this month, any plans are $10,000 for complete Cad/Cam blueprints. License is for one build. Try before you buy a production license. May pay by Bitcoin or other Crypto. Products Page... More Info
| CONTACT TEL: 608-238-6001 Email: greg@infinityturbine.com | RSS | AMP |