Study the Effect of Seeding Suspension Concentration of DD3R Particles on the Modified Surface of Α-Alumina Support for Preparing DD3R Zeolite Membrane with High Quality

In this study, seeding of DD3R particles as an important step in the synthesis of DD3R membrane with secondary growth method was investigated. Dip-coating method is used for seeding of DD3R particles on the modified surface of α-alumina supports. 0.1, 0.2 and 0.3 wt% aqueous suspensions of the DD3R seeds were prepared and each support was coated three times with dipping time of 240 s. Scanning electron microscopy (SEM) analysis was used for the investigation of the quality of seed layer formed on the support. It is shown that the uniform layer of seeds was formed with 0.2 wt% seed suspension concentration. DD3R zeolite membrane was synthesized via hydrothermal method on the support seeded with 0.2 wt% seed suspension concentration. The X-ray diffraction and SEM analysis confirmed the synthesis of uniform DD3R zeolite membrane layer on the support which can be due to the uniform distribution of the DD3R seeds. Single gas permeation tests of N2, CO2 and CH4 were carried out, so that good perm-selectivity for gas mixtures was observed

Dead-End Microfiltration of Rough Non-Alcoholic Beer by Different Polymeric Membranes

Clarification of rough nonalcoholic beer using microfiltration as an al-ternative to conventional filtration with filter aids presents scientific and technical challenges for the brewing industry. An experimental pilot plant was used to evaluate the permeability and selectivity of polymeric mem-branes in the clarification process. Cellulose acetate (CA) with pore sizes of 0.2, 0.45, 0.8, and 1.2 μm, together with cellulose nitrate (CN), nylon (NY), and polytetrafluoroethylene (PTFE) with a pore size of 0.45 μm, were used at transmembrane pressures (TMP) of 1.0 and 2.0 bar. The data cor-roborated that the flux values of the CA, CN, and NY membranes were al-most the same and reduced drastically, whereas PTFE was not permeable at 1.0 bar and its flux at 2.0 bar increased at the beginning and decreased after reaching a maximum. At both TMP, the CN membrane displayed the highest rejection of suspended particles and haze-active proteins, while re-tention of polyphenols and color were highest for the NY membrane. The lower selectivity of the PTFE membrane can be attributed to its hydropho-bicity and less interaction with the hydrophilic haze-active proteins. The results confirmed that by increasing the pore size of CA membranes the separation factor of the sensitive proteins and suspended particles decreased and permeability increased

Theoretical Analysis of Butane Isomers Separation using Various Membrane Process Configurations

Polymer is among the favorite materials used for membrane separation as they are cheap, easily cast, low maintenance cost and commercially easy to get eventhough the material needs to be altered to meet the separation industry specific needs. There are two common issues in membrane preparation which are the produced sheet are too brittle and has no strength to withstand pressure during separation process and the porosity of the sheet sometimes not suitable with the gas kinetic diameter for the separation to occur. PEBAX or Poly ether block amide is the answer for the issues as this elastomer provides good mechanical strength from the hard segment of the crystalline poly amide block while the soft polyether will drive the separation process. This unique material can be casted either by phase inversion of the PEBAX itself with other polymer or by coating them on the other polymer substrate

A comparative experimental and molecular simulation study on the mechanical and morphological behaviors of adamantane-based polypropylene composites

The main objectives of this work were to construct and characterize polypropylene and adamantane (PP/ADM) nanocomposites experimentally and to identify their mechanical properties using molecular dynamics (MD) simulation. Samples with different contents of ADMs (0.5, 1, 2 and 4 weight percent (wt%)) were prepared using melt mixing method. It was observed that ADM nanofillers had significant effects on mechanical properties (Young’s modulus) of PP nanocomposites. Furthermore an appropriate simulation model was developed to find mechanisms of dispersion and aggregation of the ADMs and to predict bulk properties of the nanocomposite. While former researches claimed that homogeneous filler dispersion exists only at the intermediate level of interfacial interaction between polymer and nanoparticle, according to results of current study entropy has substantial influence on dispersion process. In other words, entropy which controls the interfacial parameters such as how ADMs attach to the polymer chains (either by chain end or middle of the backbone), is a determining agent in dispersion and aggregation mechanism. Consequently chains entropy plays a significant role in enhancement of the nanocomposites Young’s modulus. The trend of modulus alterations demonstrated that the entrance of ADMs at the chains contact point reinforced the polymer matrix and hence increased the modulus intensively. On the other hand, relative dispersion of ADMs and their small aggregates enhanced the modulus. However, ADMs aggregation caused by attaching to the joined ends, made a dramatic decline in Young’s modulus

Evaluation of Different Polymeric Membranes Performances in Microfiltration of Rough Non-Alcoholic Beer.

In : 6th International Chemical Engineering Congress and Exhibition (IChEC 2009), 16-20 November, Kish Island, I.R.Iran, 2009.Evaluation of Different Polymeric Membranes Performances in Microfiltration of Rough Non-Alcoholic Beer.. 6. International Chemical Engineering Congress and Exhibition (IChEC 2009