Experimental and modeling investigation of ultrafine polyvinylidene fluoride hollow fiber membrane module for recovery of lactic acid from aqueous solutions

This work presents an investigation on the performance of CO2absorption into aqueous alkanolamine solution using a hollow fiber membrane gas–liquid contactor. Aqueous solution of ethanolamine (MEA), diethanolamine (DEA), 2–amino–2–methyl–1–propanol (AMP) and piperazine anhydrous (PZ) were chosen as the absorption liquids. A microporous hollow fiber membrane made of polyvinylidene fluoride (PVDF) was used as the medium for gasliquid absorption process. In this study, the operating temperature is fixed at 30°C, while the flowrate of CO2 and alkanolamine were in the range of 1000–5000 ml/min and 50–280 ml/min respectively. The feed gas was introduced directly to the shell of the module at 1–1.5 bar and the liquid flowed through the fiber lumen side. The CO2 transfer through the membrane was found to be reaction controlled and dependent on the type of amine used. The use of piperazine as an accelerator in the mixture of the absorption liquids gives a good impact on increasing the performance for the rate of CO2 transfer.

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Membrane vacuum stripping process for volatile organics removal from water using an asymmetric PVDF (polyvinylidene fluoride) hollow fiber membrane module

Water Science & Technology Water Supply ◽

10.2166/ws.2001.0101 ◽

2001 ◽

Vol 1 (5-6) ◽

pp. 65-75

Author(s):

D. Wang ◽

K. Li ◽

W.K. Teo

Keyword(s):

Hollow Fiber ◽

Polyvinylidene Fluoride ◽

Hollow Fiber Membrane ◽

Membrane Module ◽

Solution Temperature ◽

Permeation Flux ◽

Fiber Membrane ◽

Feed Concentration ◽

Water Permeation ◽

Phase Inversion Technique

The vacuum membrane stripping process (VMS) for removing a VOC (trichloroethylene) from water was studied in a polyvinylidene fluoride (PVDF) hollow fiber membrane module containing 187 fibers with a length of 0.59 m. The porous PVDF asymmetric hollow fiber used was prepared by the wet phase inversion technique. The feed solution containing trichloroethylene (TCE) was passed through the lumen of the PVDF hollow fiber. Vapors of TCE and water were transported through the pores of the membrane into the shell side maintained at a sub-atmospheric pressure, and condensed in cold traps. The effects of down-stream pressure, solution temperature, feed concentration, and feed flow rate on TCE removal, TCE permeation flux, water permeation flux and TCE concentration of the permeated solution, as well as the mass transfer coefficient were investigated. The down stream pressure and solution temperature were identified as the major factors to control VOC removal and TCE concentration in the permeate stream. A small amount of the permeated solution with higher TCE concentration was obtained at the temperature of 50°C and pressure of 80 mmHg when about 90% TCE was removed from the water.

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Removal of 1,1,1-trichloroethane from water using a polyvinylidene fluoride hollow fiber membrane module: Vacuum membrane distillation operation

Separation and Purification Technology ◽

10.1016/j.seppur.2006.05.013 ◽

2006 ◽

Vol 52 (2) ◽

pp. 301-309 ◽

Cited By ~ 58

Author(s):

Bing Wu ◽

Xiaoyao Tan ◽

K. Li ◽

W.K. Teo

Keyword(s):

Hollow Fiber ◽

Polyvinylidene Fluoride ◽

Hollow Fiber Membrane ◽

Membrane Distillation ◽

Membrane Module ◽

Fiber Membrane ◽

Vacuum Membrane Distillation

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A novel method for processing adipose-derived stromal stem cells using a closed cell washing concentration device with a hollow fiber membrane module

Biomedical Microdevices ◽

10.1007/s10544-020-00541-0 ◽

2021 ◽

Vol 23 (1) ◽

Author(s):

Shinji Hayashi ◽

Rieko Yagi ◽

Shuhei Taniguchi ◽

Masami Uji ◽

Hidaka Urano ◽

...

Keyword(s):

Stem Cells ◽

Hollow Fiber ◽

Hollow Fiber Membrane ◽

Membrane Module ◽

Fiber Membrane ◽

Cell Processing ◽

Closed Cell ◽

A Cell ◽

Novel Method ◽

Stromal Stem Cells

AbstractCell-assisted lipotransfer (CAL) is an advanced lipoinjection method that uses autologous lipotransfer with addition of a stromal vascular fraction (SVF) containing adipose-derived stromal stem cells (ASCs). The CAL procedure of manual isolation of cells from fat requires cell processing to be performed in clean environment. To isolate cells from fat without the need for a cell processing center, such as in a procedure in an operation theater, we developed a novel method for processing SVF using a closed cell washing concentration device (CCD) with a hollow fiber membrane module. The CCD consists of a sterilized closed circuit, bags and hollow fiber, semi-automatic device and the device allows removal of >99.97% of collagenase from SVF while maintaining sterility. The number of nucleated cells, ASCs and viability in SVF processed by this method were equivalent to those in SVF processed using conventional manual isolation. Our results suggest that the CCD system is as reliable as manual isolation and may also be useful for CAL. This approach will help in the development of regenerative medicine at clinics without a cell processing center.

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