자료유형  

 학위논문

Control Number  

0016930922

International Standard Book Number  

9798380583640

Dewey Decimal Classification Number  

641

Main Entry-Personal Name  

Li, Na.

Publication, Distribution, etc. (Imprint  

[S.l.] : The University of Wisconsin - Madison., 2021

Publication, Distribution, etc. (Imprint  

Ann Arbor : ProQuest Dissertations & Theses, 2021

Physical Description  

1 online resource(161 p.)

General Note  

Source: Dissertations Abstracts International, Volume: 85-04, Section: B.

General Note  

Advisor: Etzel, Mark R.

Dissertation Note  

Thesis (Ph.D.)--The University of Wisconsin - Madison, 2021.

Restrictions on Access Note  

This item must not be sold to any third party vendors.

Summary, Etc.  

요약Polyethersulfone (PES) ultrafiltration membranes of 5-10 kDa molecular weight cut off (MWCO) are widely used for cheese whey concentration, but these tight membranes are slow to filter whey through the membrane. Although membranes having a larger MWCO speed filtration, more proteins leak through the wider pore of the membrane. By placing an ionic charge on the surface of the wide pore membrane, proteins of like charge are rejected by electrostatic repulsion rather than size-based filtration and prevent protein leakage. In the present work, a new method is described that places charges on the surface of a finished PES ultrafiltration membrane by passing an incubation solution through the membrane. The incubation solution contains an organic solvent, water, and a charged polymer. The proposed mechanism is that the organic solvent swells the membrane allowing diffusion of the charged polymer into the membrane and removal of the organic solvent un-swells the membrane trapping the charged polymer in the membrane. The Hansen solubility parameter distance (Ra) predicts swelling of a polymer in a solvent. It was found that solvent-water blends having Ra values of 19.9 to 23.9 MPa1/2 work best to swell the membrane and facilitate the diffusion transfer of the charged polymer. It was also found that a charged polymer having a phenyl ring had a greater thermodynamic affinity for the PES membrane polymer than for the solvent blend. This affinity provided a thermodynamic driving force for diffusion transfer of the charged polymer. Negatively charged polymers, such as polystyrenesulfonate and hydrolyzed styrene-maleic anhydride, and positively charged polymers, such as styrene-maleic anhydride imide and poly(diallyldimethylammonium chloride), were used to make charged membranes successfully. Scale-up experiments from disc membranes to spiral-wound membranes were successful, resulting in a 1,500x increase in membrane area, and a transition from a dead-end to a crossflow mode of operation. A 200 kDa MWCO negatively charged spiral-wound membrane increased protein retention by 34% compared to a 10 kDa uncharged spiral-wound membrane, and at twice the whey filtration flux. This work benefits the dairy industry because high speed charged membranes use less energy, reduce protein losses, and lower the cost of manufacture of dairy protein ingredients.

Subject Added Entry-Topical Term  

Food science.

Subject Added Entry-Topical Term  

Chemical engineering.

Subject Added Entry-Topical Term  

Polymer chemistry.

Subject Added Entry-Topical Term  

Biochemistry.

Index Term-Uncontrolled  

Charged membrane

Index Term-Uncontrolled  

Cheese whey

Index Term-Uncontrolled  

Protein concentration

Index Term-Uncontrolled  

Protein separation

Index Term-Uncontrolled  

Ultrafiltration

Index Term-Uncontrolled  

Polyethersulfone

Added Entry-Corporate Name  

The University of Wisconsin - Madison Food Science

Host Item Entry  

Dissertations Abstracts International. 85-04B.

Host Item Entry  

Dissertation Abstract International

Electronic Location and Access  

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Control Number  

joongbu:644007