Removal of Phenolic Pollutants from Water over BEA and HY Zeolites in Batch Conditions

A single adsorption isothermal study was performed over HY and BEA zeolites in order to determine their adsorption capacities for phenol, ortho-nitrophenol and para-nitrophenol. The experiments were realized in batch reactor and the isotherms were modelized by the Fowler-Guggenheim equation. During the adsorption process weak zeolite-sorbate interactions and more significant sorbate-sorbate attractions were identified. The adsorption was not linked to the molecular size of the sorbates and a strong correlation was established between the adsorption compound was the best adsorbed. The removal performances capacities and the dipole moments of the sorbates. The most polar of the zeolites depended on their hydrophobicity.

Synthesis and characterization of hierarchical nanoporous HY zeolites from acid-activated kaolin

Hierarchical nanoporous HY zeolites were synthesized from acid-activated kaolin. The hierarchical factor （HF） was maximized by varying the aging and crystallization time. This was achieved by maximizing the external surface area without greatly reducing the micropore volume. The resulting products were characterized using X-ray diffraction （XRD）, X-ray fluorescence, N2 adsorption, and NH3 temperature-programmed desorption. The nanoporous HY zeolite with the highest HF was obtained by aging for 48 h and a crystallization time of 24 h. The acidiW and crystallinity varied depending on the operating parameters. Incorporation of an appropriate amount of NaCI was also vital in maximizing the HF, crystallinity, and acidity. The sample crystallinities were determined by comparing their XRD peak intensities with those of a conventional Y zeolite. The results show that optimizing this process could lead to a widely acceptable commercial route for FIY zeolite production.

Hydrogenolysis of glycerol over HY zeolite supported Ru catalysts

An enhanced active and selective catalyst consisting of ruthenium supported on dealuminated HY zeolite has been prepared by a wet im- pregnation method. It was found that BET surface area of Ru/HY catalysts significantly increases after HC1 treatment. This treatment also increases the concentration of strong acid sites in the catalyst. The hydrogenolysis of glycerol over 5 wt% Ru/HY catalyst was investigated at 190-220℃ , an initial H2 pressure of 3-6 MPa, and in 20 wt% glycerol aqueous solution, The results indicate that HC1 treated Ru/HY catalyst shows higher activity compared with the untreated Ru/HY catalyst, and that the glycerol hydrogenolysis efficiency is influenced by the porosity and acidity of the support. A selectivity to 1,2-PDO of 81.3% at a glycerol conversion of 60.1% under 3 MPa H2 pressure and 220 ℃ for 10 h was achieved over the modified Ru/HY catalyst with a 1.0 mol/L HC1 treatment. It has also been shown that a longer reaction time, a higher temperature and a higher H2 pressure have the positive effects on the glycerol hydrogenolysis efficiency of the enhanced Ru/HY.

Amine-immobilized HY zeolite for CO_(2) capture from hot flue gas

Solid amine-based adsorbents were widely studied as an alternative to liquid amine for post-combustion CO_(2)capture(PCC).However,most of the amine adsorbents suffer from low thermal stability and poor cyclic regenerability at the temperature of hot flue gases.Here we present an amine loaded proton type Y zeolite(HY)where the amines namely monoethanolamine(MEA)and ethylenediamine(ED)are chemical immobilized via ionic bond to the zeolite framework to overcome the amine degradation problem.The MEA and ED of 5%,10%and 20%(mass)concentration-immobilized zeolites were characterized by X-ray diffraction,Fourier-transform infrared spectroscopy,and N_(2)-196℃ adsorption to confirm the structure integrity,amine functionalization,and surface area,respectively.The determination of the amine loading was given by C,H,N elemental analysis showing that ED has successfully grafted almost twice as many amino groups as MEA within the same solvent concentration.CO_(2)adsorption capacity and thermal stability of these samples were measured using thermogravimetric analyser.The adsorption performance was tested at the adsorption temperature of 30,60 and 90℃,respectively using pure CO_(2)while the desorption was carried out with pure N_(2)purge at the same temperature and then followed by elevated temperature at 150℃.It was found that all the amine@HY have a substantial high selectivity of CO_(2)over N_(2).The sample 20%ED@HY has the highest CO_(2)adsorption capacity of1.76 mmol·g^(-1)at 90℃ higher than the capacity on parent Na Y zeolite(1.45 mmol·g^(-1)only).The amine@HY samples presented superior performance in cyclic thermal stability in the condition of the adsorption temperature of 90℃ and the desorption temperature of 150℃.These findings will foster the design of better adsorbents for CO_(2)capture from flue gas in post-combustion power plants.

One-pot glycerol conversion to acrylic acid catalyzed by Cu modified HY zeolite synthesized from natural resources and pro-analytical precursor

The conversion of glycerol to acrylic acid was carried out by the one-pot process method.The catalyst used in this conversion is Cu-modified HY zeolite synthesized using pro-analytical precursors and alternative precursors from natural resources i.e.,Indonesian natural zeolite and kaolin.The crystal structure and physicochemical properties of catalysts were determined by various characterization techniques such as XRD,FTIR,SEM-EDX,TEM,SAA,and TPD-NH_(3).Based on XRD analysis,it shows that HY and CuHY,both from synthetic and alternative precursors,are confirmed to have typical peaks of Y zeolite.EDX mapping images show a uniform distribution of Cu on the HY surface.In addition,the TEM analysis also shows uniform particle size distribution.The results of catalytic glycerol conversion show that Cu-modified HY catalysts give a higher acrylic acid yield than HY.The results also show that the highest yield of acrylic acid was obtained in 27.5%and 25.8%at a dehydration time of 3 h using pro-analytical and natural resources CuHY catalyst,respectively.The Cu-modified HY catalysts having weak acid sites show the best catalytic activity in the conversion of glycerol to acrylic acid.

Effect of the Interference Instant of Zeolite HY Catalyst on the Pyrolysis of Pubescens

A laboratory reactor was designed to test the effect of the interference instant of HY on the pyrolysis of pubescens.The time instant for intermediate species from pyrolysis to contact HY was controlled by varying the position of the catalyst bed relative to the pyrolytic cell.It was found that the effect of the interference instant was significant on the variation of different intermediate species,and the yield and quality of the products.The results also showed that,with the increase in the distance between the pyrolytic cell and the catalyst bed,the yield of liquid and relative content of the organics such as aldehyde,phenols,etc.,decreased,while the yield of residue and relative content of acetic acid increased.The deoxygenation of the intermediate species was favored when the catalyst exerted its performance on them immediately after their formation.

Catalytic Acylation of Anisole over Some Zeolites

Methoxyacetophenone(4 MAP) was synthesized by the acylation of anisole with acetic anhydride in the presence of HY zeolite. The addition of an appropriate amount of some solvent such as dichloromethane, chloroform, carbon disulfide or chlorobenzene to the reaction system can improve the yield of the acylated product to a certain extent. HY zeolite used can be recovered, and reused after being regenerated, obtaining almost the same yield of 4 MAP as the fresh zeolite.