The Pfeffer Zelle (Pfeffer Cell Apparatus), invented by Wilhelm Pfeffer [6] in 1877, measured the minimum pressure needed to prevent a pure solvent from passing into a solution across a semi-permeable membrane, called osmotic pressure. The apparatus provided Pfeffer with a way to quantitatively measure osmotic pressure. Pfeffer devised the apparatus in the 1870s at the University of Basel [7] i...

Reverse osmosis (RO) is a water purifcation technology that uses a semipermeable membrane to remove ions, molecules, and larger particles for the production of drinking water. The frst RO membrane for seawater desalination, wastewater treatment and other applications were made of cellulose acetate. But, the polyamide thin-flm composite membrane that can tolerate wide pH...

Interest in reuse of process water from the food industry has reinforced the importance of controlling and monitoring the effectiveness and reliability of treatment systems regarding removal of organic matter and microorganisms. The ability of adenosine triphosphate bioluminescence, conductivity, turbidometry, absorbance, and multichannel fluorescence spectroscopy for indirectly monitoring the ...

Wastewater produced by the crew members on a long-term space mission needs to be recovered as potable water. Reverse osmosis (RO) has long been in use as a physical membrane separation technology for wastewater treatment. However, membrane fouling and concentration polarization have limited the efficiency for high recovery reverse osmosis systems. An advanced high pressure rotating RO device wa...

Forward osmosis (FO) technology has been applied for removal of chromium (Cr) from water environment. Comparison the efficiency Cr(VI) and Cr(III) was investigated by changing several operational conditions. The pH feed solution plays an important role in rejection Cr. increased with increasing pH, while stable. It also demonstrated that Cr higher when membrane active layer faces compared to dr...

Co-mixed cellulose acetate butyrate and permutit in a definite composition was prepared and coded as MRS-2.The membrane potential was measured with uni-uni valent electrolyte, NaCl solutions using saturated calomel electrodes (SCEs).The effective fixed charge density of the membrane was determined by TMS method and it showed dependence on the porosity, charge on the membrane matrix, charge and ...

This study seeks to evaluate the performance and economic feasibility of the forward osmosis (FO)-reverse osmosis (RO) hybrid process; to propose a guideline by which this hybrid process might be more price-competitive in the field. A solution-diffusion model modified with film theory was applied to analyze the effects of concentration polarization, water, and salt transport coefficient on flux...

A two-dimensional thin-walled capsule of a flexible semi-permeable membrane is adhered onto a rigid planar substrate under adhesive forces (derived from a potential function) in the presence of osmosis across the membrane. The capsule is immersed in a hypotonic and diluted binary solution of a non-electrolyte solute. The Stokes flow problem is solved by the immersed interface method (IIM) with ...