Stainless Steel Stirred Cell

Nanofiltration experiments were carried out in a stainless steel stirred cell with an Amicon magnetic stirrer on a magnetic heater plate (Industrial Equipment Control, Australia). The calibration is shown in Figure 4.2. 

Figure 4.4 Stainless steel stirred cell set-up. A stirred cell, volume 185 mL B magnetic stirrer (Amicon, driven by magnetic stirrer table) C membrane D stainless steel porous support E reservoir volume 2000 mE, F pressurised instrument air inlet, G feed inlet, pressure release and safe valves H permeate outlet (to balance and PC).

Figure A2.3 Drawing of stainless steel stirred cell. All dimensions are in mm.

The experiments were run in a 200 ml vessel with electrical heating and stirring by a magnetic bar. The pressure was followed by a Digibar. AA and AIBN (both from Merck) were used as received, CCh-SFE-grade was used from Messer Griesheim. For visual experiments a stainless-steel optical cell with movable piston could be used. The reaction conditions were 65°C and 200 bar and the reaction time was about 6h. 

The device consists of a low thermal mass test cell of 110 ml volume. This is made of stainless steel with a 0.015-mm wall thickness, but test cells made from other materials can be used. The contents of the cell are mixed using either a magnetically driven stirring bar or a direct drive agitation test cell. The test cell is... 

Diffusion Cells. The two chamber diffusion cells (9) were assembled by a No. 18 spring clamp with the hairless mouse3skin sandwiched in between. The volume of each half cell was 2.0 cm. An 8 mm stirrer made of stainless steel and equipped with a small teflon propeller was driven by a 150 rpm constant speed motor (Hurst, Princeton, IN) was utilized for stirring. The assembled cell was then immersed in a 37°C heated water bath (Haake, Karlsruhe, W. Germany), so that the stirring and sampling ports were the only components above the water surface. The diffusion cell was kept for 10 minutes in the water bath to allow temperature equilibrium prior to any experiment. Then ethanol/saline mixtures preheated to 37°C were pipetted into the cell to start an experiment. 

Until now, bioreactors of various types have been developed. These include loop-fluidized bed [14], spin filter, continuously stirred turbine, hollow fiber, stirred tank, airlift, rotating drum, and photo bioreactors [1]. Bioreactor modifications include the substitution of a marine impeller in place of a flat-bladed turbine, and the use of a single, large, flat paddle or blade, and a newly designed membrane stirrer for bubble-free aeration [13, 15-18]. Kim et al. [19] developed a hybrid reactor with a cell-lift impeller and a sintered stainless steel sparger for Thalictrum rugosum cell cultures, and cell densities of up to 31 g L1 were obtained by perfusion without any problems with mixing or loss of cell viability the specific berberine productivity was comparable to that in shake flasks. Su and Humphrey [20] conducted a perfusion cultivation in a stirred tank bio-... 

Stirred-tank bioreactors are generally glass or stainless steel tanks with an impeller to provide mixing. Air or oxygen is usually bubbled through the media to supply oxygen to the cells. An example of a stirred-tank bioreactor is depicted in Figure 32.3. Sterility is obviously an important issue in mammalian cell culture, and therefore stirred-tank systems... 

Mengual et al. [37] have used Lewis ceU (stirred cell) for their experiments on MD (Figure 19.14). This mainly consists of two equal cylindrical chambers made of stainless steel having a length of 20.5 cm. The membrane was fixed between the chambers by means of a PVC holder. Three viton O-rings were employed to eliminate leaks in the assembly. The membrane surface area exposed to the flow was 27.5 cm. ... 

The windows are 3/4 inch x 3/4 inch quartz. A triangular magnetic stir bar at the bottom of the cell stirs the lower phase in the cell. A rectangular stainless steel wire mesh "flapper on a shaft set into the magnetic stir bar stirs the upper phase. The solid sample rests on a stainless steel wire mesh platform at the level of the side window of the view cell. 

Reactions in microemulsions and emulsions have been performed in a stainless steel variable-volume view cell (2 in. (5.1 cm) o.d., 11/16 in. (1.7 cm) i.d., 35.2 mL total volume), equipped with a piston and a sapphire window (1 in. (2.5 cm) diameter by 3/8 in. (0.95 cm) thick) [44,55]. Water, nucleophile (e.g. KBr), surfactant (0.5 wt. %), and an internal standard were added to the cell. The cell was sealed with the sapphire window, pressurized with a known amount of CO2 from an ISCO pump, and heated to the desired temperature. An emulsion was formed as discussed above by recirculating the contents of the vessel (mixed with a teflon-coated magnetic stir bar) through a 0.254 mm diameter by 5 cm long steel capillary tube with a... 

In the case of the sulfur-rich mixtures of sulfur and phosphorus, approximately 120 grams of the mixture was placed in a borosilicate glass beaker, which was covered with a niobium plate at the higher temperatures (>350°C) to decrease sulfur losses by vaporization. The cell was placed in a 500 ml alumina secondary container, and this assembly was located inside a sealed stainless steel vessel which was heated by Nichrome resistance wire. The cover of the vessel had access ports for a stirring... 

The cell was equipped with a pressure gauge mounted in the stainless steel line after the air cylinder, a stainless steel reservoir with a volume of 2 L, a pressure release valve, a fluid inlet and oudet connection, a pressure safetj- valve, and a refill opening on top of the reservoir. On top of the stirred cell, a fluid inlet connection, a pressure release valve and a temperature probe fitting were mounted. The temperature was measured with a PT 100 probe, connected to a Kane-May KM 330 indicator. 

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