Effect of Soda Concentration on the Morphology of MFI-Type Zeolite Membranes

Soydas, Belma
Culfaz, Ali
Kalıpçılar, Halil
MFI-type zeolite membranes were hydrothermally synthesized as a thin layer on macroporous -alumina discs coated with 1m MFI-type seed crystals as seed. The effect of soda (Na2O) concentration on the morphology of the membranes was investigated. Soda concentration, and thus the hydroxyl ion concentration, was changed between 0.25 and 6.5 mol/mol gel. At low soda concentrations the crystals forming the layer exhibited mostly (h0h)/c-axis orientation, but at high soda concentrations a membrane layer formed from randomly oriented crystals. The membranes showed high H-2/n-butane ideal selectivity of 476 and 36 at 25 degrees C and 150 degrees C, respectively.


Synthesis of ZSM-5-type zeolite membranes on, porous disks loaded with different amounts of seed
Dincer, Eser; Kalıpçılar, Halil; Culfaz, Ali (American Chemical Society (ACS), 2008-07-16)
ZSM-5-type zeolite membranes were synthesized at 130 degrees C on alumina supports coated with seed crystals by vacuum seeding. Compact and uniform ZSM-5 layers were formed on the support surfaces when the amount of seed was less than 1 mg/cm(2). Higher loading of seed crystals resulted in an asymmetric structure with a compact and uniform ZSM-5 layer on top, the support at the bottom, and the seed layer in between. Fifty-one membranes were prepared on supports coated with different amounts of seed. About 7...
Effects of pH, Initiator, Scavenger, and Surfactant on the Ozonation Mechanism of an Azo Dye (Acid Red-151) in a Batch Reactor
Oezbelge, Tuelay A.; Erol, Funda (Informa UK Limited, 2009-01-01)
In this study, an initiator (Fe2+) and a scavenger (CO32(-)) were used at different concentrations in a batch reactor to investigate the reaction mechanism of ozonation of a model azo dye, namely Acid Red-151 (AR-151). Also, the effect of a nonionic surfactant known as a major pollutant in many industrial wastewaters, namely polyethylene glycol (PEG), was observed on the degradation rate of AR-151. The experimental parameters and their ranges were: pH (2.5-10), initiator (0.8-50mg/L of Fe2+), surfactant (10...
Şümnü, Servet Gülüm (Wiley, 1994-08-01)
Pears were coated with different concentrations of Semperfresh or with Johnfresh edible coatings after storage for five months at 0C to determine the effects of coatings on poststorage quality. Coating levels were effective for extending the poststorage life and delaying ripening. Both Semperfresh and Johnfresh treated pears had better color, firmness, ascorbic acid, titratable acidity, soluble solid retention than control pears. Although Semperfresh was effective for the reduction of respiration and weight...
Development and application of novel bio-magnetic membrane capsules for the removal of the cationic dye malachite green in wastewater treatment
Ali, Imran; Peng, Changsheng; Naz, Iffat; Lin, Dichu; Saroj, Devendra P.; Ali, Mohsin (Royal Society of Chemistry (RSC), 2019-01-29)
Novel bio-magnetic membrane capsules (BMMCs) were prepared by a simple two-step titration-gel cross-linking method using a polyvinyl alcohol (PVA) and sodium alginate (SA) matrix to control the disintegration of phytogenic magnetic nanoparticles (PMNPs) in an aqueous environment, and their performance was investigated for adsorbing cationic malachite green (MG) dye from water. The prepared BMMCs were characterized by FTIR, powder XRD, SEM, EDX, XPS, VSM and TGA techniques. The findings revealed that the hys...
Effect of Midsynthesis Addition of Silica to the Synthesis Medium on the Properties of MFI-Type Zeolite Membranes
Soydas, Belma; Kalıpçılar, Halil; Culfaz, Ali (American Chemical Society (ACS), 2010-06-02)
Thin zeolite membranes of MFI type were prepared on alpha-Al2O3 supports by midsynthesis addition of silica in a recirculating flow system at 95 degrees C The synthesis was started with the batch composition of 80SiO(2): 30TPAOH:1500H(2)O which was changed to 80SiO(2)center dot 9TPAOH:1500H(2)O by addition of silica Mkt 24, 48, or 72 h Compared to synthesis at constant composition. it is possible to affect the rates of nucleation and crystal growth to obtain membranes with better quality by changing the ove...
Citation Formats
B. Soydas, A. Culfaz, and H. Kalıpçılar, “Effect of Soda Concentration on the Morphology of MFI-Type Zeolite Membranes,” CHEMICAL ENGINEERING COMMUNICATIONS, pp. 182–193, 2009, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/35570.