Preparation of High Density Cellulose Membrane for Pressure Flux Essay

Preparation of High Density Cellulose Membrane for Pressure Flux Essay

Length: 1775 words (5.1 double-spaced pages)

Rating: Powerful Essays

Open Document

Essay Preview

3.1 Membrane porosity properties

A. The Effect of Pulp DP
Table 2 show the high DP of pulp (Exp. Code A) result in higher porosity (low density) and water permeability of membrane. As it is well known that the molecular weight of membrane polymer has a great effect on the membrane performance while molecular weight is depend on Degree of Polymerization which indicate number of repeat unit (monomer) in chain molecules. Polymer with high degree of polymerization will have longer chain and larger molecule compare to a polymer with low degree of polymerization. This long and large chain make more entangle occur between polymer chain but less chain mobility which cause NMMO difficult to break the entangled cellulose hydrogen bond during dissolution process result in less homogenous casting solution. Moreover this long chain and less chain mobility avoid polymer chain to arrange closer each other during coagulation process induce more porous part on membrane. Therefore when membrane composed of mixed cellulose DP the porosity is decrease due to the low cellulose DP can reduce this mechanism, however this tend to induce a bigger mean pore size since the low homogeneity in casting solution.

B. The Effect of Cellulose Concentration in casting solution
To obtain membranes with good performance, the polymer concentration of the casting solution usually is the key factor affecting the permeation rate, rejection and mechanical properties of membranes.[21] However this is restricted by process ability as well as production cost when higher concentration applied. In this work we use 11% as maximum concentration due to at 12% concentration the casting solution is too viscous so as during film casting process is difficult to obtain an eve...

... middle of paper ...

...asymmetric cellulose hollow fiber membrane Journal of Membrane Science 246 (2005) 157–165.
12. E. Maia, A. Peguy, S. Perez, Cellulose organic solvents. I.The structures of anhydrous N-methylmorpholine N-oxide and NmethylmorpholineN-oxide monohydrate, Acta Cryst. B37 (1981)1858.
13. W. Berger, M. Keck, B. Philipp, On the mechanism of cellulose dissolution in non-aqueous solvents, especially in O-basic systems,Cell Chem. Technol. 22 (1988) 387.
14. E. M. Andresen, G. R. Mitchell, Polymer 1998, 39, 7127.
15. H. Chanzy, M. Dube, R. H Marchessault, J. Polym. Sci.,Polym. Lett. Ed. 1979, 17,
20.F. Carrillo, X. Colom, J.J. Su~nol, J. Saurina; Structural FTIR analysis and thermal characterization of lyocell and viscose-type fibres;European Polymer Journal 40 (2004) 2229–2234
21. X. G. Jian, Y. Dai, G. H. He, G. H. Chen, J. Membr. Sci.1999, 162, 187

Need Writing Help?

Get feedback on grammar, clarity, concision and logic instantly.

Check your paper »

Cellulose Pre-treatment: Cellulose Binding Domain (CBD) Essay

- CELLULOSE BINDING DOMAIN (CBD) Among the different cellulases, some prefer amorphous substrates whereas others are also able to attack the highly ordered, crystalline cellulose. Comparative studies of many different cellulases have been used to identify common features enabling the enzyme to hydrolyze cellulose crystals (Wilson et al., 1985; Davies and Henrissat, 1995). Tight adsorption with cellulose is linked with good catalytic activity (Klyosov, 1990). Most cellulases that are effective against crystalline cellulose share a modular structure composed of a catalytic domain linked to a distinct cellulose-binding domain (Tomme et al., 1995b)....   [tags: enzyme, cellulose, fungal]

Powerful Essays
777 words (2.2 pages)

How Molecules Can Move Across A Semi Permeable Membrane Essay examples

- The purpose of this lab is to determine which molecules can move across a semi-permeable membrane. The hypothesis for this experiment is as follows; As the smaller molecules of iodine travel through the “cell membrane” the artificial cell will gain mass. Dialysis tubing, a thin membrane that behaves in much the same way as a living cell’s actual plasma membrane, was used to test this experiment. After filling the dialysis tubing with the starch and glucose solutions, the artificial cell was then submerged in a water and iodine solution, and the results we’re recorded after 30 minutes....   [tags: Cell membrane, Cell, Semipermeable membrane]

Powerful Essays
792 words (2.3 pages)

Cellulose Essay

- Cellulose is the most globally abundant biopolymer, accounting for 1.5x1012 tonnes of annually available biomass. [1] As such, there has been considerable interest in recent years in the development of new technologies for the utilization of cellulose as a feedstock for the production of fine chemicals [2-5] and hydrogen.[6-10] Amongst these technologies, hydrothermal conversion is of growing interest since pre-drying of feedstocks are avoided and the water gas shift can be performed in situ using platinum group metal catalysts....   [tags: Research Analysis]

Powerful Essays
814 words (2.3 pages)

Investigating The Density Of A Set Of Plastic Beads Essay

- The objective of this lab experiment was to determine the density of a set of plastic beads by using two different methods and decide which method was better. Density is a physical property that is defined as the ratio of an object’s mass to an object’s volume. Also, density can be described as the measurement of how compact a substance is in a given space. To find an object’s density, it is necessary to measure the object’s mass, the amount of matter present, and volume, the space it takes up. Also when studying density, it is key to note how objects with varying densities behave....   [tags: Density, Buoyancy, Archimedes, Volume]

Powerful Essays
1195 words (3.4 pages)

Voltage Sensor Of Membrane Potentials Essay

- As the article was reviewed, it is clear that the main purpose of the research presented was to create a voltage sensor that would send out fluorescent signals and return responses from the actions of membrane potentials. The researchers also wanted a voltage sensor that would keep track of the membrane potentials in neurons at quicker rates by using a microscope that not only detects refection and adsorption but also fluorescence. The method, in this design plan, places the fluorescent protein into the extracellular, S3-S4, loop domain....   [tags: Neuron, Action potential, Membrane potential]

Powerful Essays
1413 words (4 pages)

Essay about The Membrane Of The Cell Membrane

- Cells are living things that requires substances to be imported into the cell for growth and repair just as a human, or animal, needs to eat for growth and repair. Unlike the human or animal that has arms, jaws, or external tools to collect and consume food, the basic cell does not have any external appendages to readily obtain the substances it needs. This does not leave the cell without any way to obtain the required substances, obviously otherwise they would all be very short lived, and the ways they obtain substances differ in the required energy and the substance being obtained....   [tags: Cell membrane, Cell, Lipid bilayer]

Powerful Essays
730 words (2.1 pages)

Essay on Cells And The Cell Membrane

- Despite the fact that there is still plenty to ascertain about cells, what is known so far has had an extensive impression on a multitude of scientific fields. The analysis of cells has even assisted in the investigation to more effectively understand cancer. Cells are essentially the building blocks of life. As a matter of fact, all organisms varying from the minuscule and simple organisms to the gigantic and sophisticated organisms are made up of cells. Truly, something that is noteworthy about cells is that although they are so small they have even smaller organelles with many important functions within them....   [tags: Cell wall, Cell, Cell membrane, Bacteria]

Powerful Essays
1577 words (4.5 pages)

Essay The Functions of Erythrocyte Membrane

- The erythrocyte membrane has many functions, the first of which is to serve as an impenetrable fluid barrier which separates the inside contents of the cell from the plasma. The membrane allows it to transport O2 and CO2 by maximizing the ratio of surface area to volume with its biconcave disc shape. The membrane is also strong and is constantly going through shape and metabolic changes and has a tensile or lateral strength that is greater than that of steal. The membrane is also more elastic than a comparative latex membrane, this strength and elasticity allows for deformability (Solberg, 2013)....   [tags: cell membrane, red blood cells, cholesterol]

Powerful Essays
1031 words (2.9 pages)

Effect of Population Density in Sexual Development, Essay

- The gametophytes used in this experiment are of C-ferns. They tend to mature and produce spores at temperature of 28oC and conditions of high humidity. The spores that germinate first are hermaphrodites. Hermaphrodites tend to produce a pheromone called antheridiogen. It is this pheromone that causes later germinating spores to become male. In wild type culture of C-ferns, it is expected that there will be a high concentration of antheridiogen since the hermaphrodites are producing antheridiogen....   [tags: population density,sexual development,gametophytes]

Powerful Essays
1237 words (3.5 pages)

The Effect Of Intracellular Fluids On The Cell Membrane Essay

- Human cells are partially made up of liquids that are both inside and outside of our cells. The water inside the cell is called intracellular fluid (ICF) and makes up about 42% of the total body weight. On the other hand, extracellular fluids (ECF) usually denote all body fluid outside of the cells. In order to define which area the fluids are based, they are determined by its location to the cell membrane. For instance, if the fluids are found to be on the outside of the cell membrane, it would signify that we are viewing ECF....   [tags: Blood, Potassium, Cell membrane, Glucose]

Powerful Essays
722 words (2.1 pages)