A STUDY OF THE ELECTROPHORETIC MOBILITY OF CARBON, COTTON, AND WOOL IN AQUEOUS AND NON-AQUEOUS DETERGENT SOLUTIONS

119 Pages·06.603 MB·English

by  STUBBLEBINE, WARREN

The Pennsylvania State College
The Graduate School
Department of Chemistry
A STUDY OF THE ELECTROPHORETIC MOBILITY OF CARBOR,
COTTON, AND WOOL IN AQUEOUS AND NON-AQUEOUS
DETERGENT SOLUTIONS
A D issertation
ty
Warren Stubblebine
Submitted in P a rtia l Fulfillm ent
of the Requirements
fo r the Degree of
Doctor of Philosophy
> in
Chemistry
January, .1942
Approved: $ -(? .■ <
Head of Department
Approved : (J g ju ^ u d ji / o>
Professor of Te emistry
A 0 -K H 0 W L E D G M B H T S
The author wishes to express h is sincere appreciation
to J. Fred O esterling and to Pauline Beery Mack, under whose
d irectio n th is study was c arried out.
To the follow ing, the author wishes to express h is
thanks fo r a ssista n ce rendered in various ways throughout
the course of th e study:
F. J. Malloy, who constructed the glass m icroelectropho­
re sis c e ll;
E. J. Stubblehine, who a ssiste d w ith the design and
construction of the c e ll clamp; and
Jane Kemmerling Stubblebine, who took charge of the many
c le ric a l d e ta ils associated with the preparation of th is
d isse rta tio n .
The author, moreover, is indebted to the Pennsylvania
laundryowners A ssociation for placing a t h is disposal the
f a c i li t ie s of th e ir research fellow ship1 so that th is in v e s ti­
gation might be completed.
I
i
T A B L E 0 g 0 OE I EH 1 S
Page
General In tro d u ctio n .............................................................. 1
Part I - Electrophoretic M obilities of Cotton and of
Carbon P articles in Aqueous Solutions
I n tr o d u c tio n ....................................................................................... 5
Method of P rocedure...................................... 6
E q u ip m en t........................................... 6
M icroelectrophoresis Cell ................................. 6
Microscope .................................................................... 9
Light S o u r c e .....................................................................10
Microelectrophoresis Cell Clam p..........................11
Constant Temperature A ir-B ath . . 11
Current Control U n i t ................................. 15
Calibration of Equipm ent......................................................24
C alibration of Microscope Pine Adjustment 24
Calibration of the Eyepiece Micrometer . 25
Calibration of the Microelectrophoresis-
Cell . ........................................... 25
Determination of p H ................................................................28
Determination of Specific Resistance of the
Suspensi o n ............................................... 29
M aterials . . . 'v '~ ..................................................................29
C o t t o n ...................................................................................31
C a r b o n ...................................................................................32
S o a p ................................. 33
Preparation of D isp ersio n s............................ . . . 33
TABLE OP OOHTMTS (Continued)
Page
Procedure for Determining the Electrophoretic
Mobility of Carbon and Cotton . ............................. 35
Presentation of D a ta ......................................................................... 38
Effect of Varying Concentrations of Sodium
Hydroxide, Sodium Carbonate, Sodium Sesquicar-
bonate, and Sodium M etasilicate upon th e
Electrophoretic Mobility of Cotton and Carbon
P a r tic le s ........................................... 38
Effect of Low Titer Soap in Various Concentra­
tions upon the Electrophoretic Mobility of Cotton
and Carbon P articles .......................................................... 43
Effect of One-Tenth Per Cent. Low T iter Soap in
Conjunction with Each of the Pour A lkalies,
Sodium Hydroxide, Sodium Carbonate, Sodium Ses-
quiearbonate, and Sodium M etasilicate, upon the
Electrophoretic Mobility of Cotton and Carbon
P articles . . . . . . . . . . ....................................... 45
D iscu ssio n ................................................................................................. 59
Effect of the A lkalies, Sodium Hydroxide, Sodium
Carbonate, Sodium Sesquicarbonate, and Sodium
M etasilieate on the Electrophoretic Mobility of
Cotton and Carbon p articles ............................................ 60
Effect of Low Titer Soap in Various Concentra­
tions upon the Electrophoretic Mobility of
Cotton and Carbon p a r t i c l e s ........................................... 64
Effect of One-Tenth Per Cent. Low T iter Soap
in Conjunction With Each of the A lkalies,
Sodium Hydroxide, Sodium Carbonate, Sodium Ses­
quicarbonate, and Sodium M etasilicate on the
Electrophoretic Mobility of Cotton and Carbon
P a r tic le s ............................................. . . . ' ............................ 66
Belati onships Between Electrophoretic Mobility
and D e te rg e n c y ......................................................................... 69
Electrophoretic Mobility and Practical
Soil Removal.................................................................... 69
Magnitude and Sign of Charge on Car­
bon and on Cotton in Relati on to
Detergency ............................ 69
TABLE OF CONTENTS (Continued)
Page
Maximum Soil Removal in Relation to
Electrophoretio M obility . . . . . . . 70
Part II - Electrophoretic M o tilities of Wool and o f Carbon
P articles in Non-Aqueous Solutions
Introduction ........................................... 74
Method of P ro ced u re................................................ 75
Equipm ent........................................................................... 75
Vacuum-Tube Voltmeter ....................... 75
C alibration of Equipm ent................................................ . 82
M aterials ...........................................................................82
Solvents . . . . . . . . . . . . . . . . . 82
Potassium Oleate D e te r g e n t . 83
C a r b o n .......................................................... 83
W o o l ........................................... 83
Preparation of D isp e rsio n s................................................. 84
Procedure for Determining the Electrophoretic
Mobility of Carbon and of W ool..............................................85
Presentation of Data ..........................87
E ffect of Various Concentrations of Potassium
Oleate Soap in Stoddard Solvent Solutions (Con­
taining 1.5 per cent, by Volume of Acetone) on
the Electrophoretic M obility of Carbon and of
Wool Parti cl e s .................................. 87
Effeot of Various Concentrations of Potassium
Oleate Soap in Carbon Tetrachloride Solutions
(Containing 1.5 per c ait. by Volume of Acetone)
on the Electrophoretic Mobility of Carbon and
on Wool P a r t i c l e s .......................................................... 89
Discussion ............................. 93
Magnitude and Sign of Charge on Carbon and on
Wool in Relation to D etergency........................ 93
TABLE OE CONTENTS (Continued)
Page
Relationship of E lectrophoretic M obility to
P ractical Soil Removal .......................................................... 97
Precision of Electrophoretic M obility Measure­
ments .........................................................................................................98
Summary............................................................................................................ I l l
Bibliography . ................................................................................... 112
G E N E R A L I H B 0 D U C I I 0 H
Detergency studies in the te x tile chemistry laboratory
at The Pennsylvania State College have indicated th at there
is some force existen t between so il p articles and te x tile
fib ers, the resu lt of which is to hold the s o il to the fib er,
more or less firm ly. This force was thought to be electrica l
in character, since it was known tbat so il p articles and te x ­
t ile fibers possess an electrica l charge iiiien they are d is ­
persed in various liq u id s.
It seemed desirable, therefore, to investigate the charge
on the surface cf te x tile fib ers and of carbon p articles (re­
presentative of a common type of s o il), when they are dispersed
in various detergent solutions, in an effort to arrive a t a
more complete understanding of the reasons for detergent action
insofar as the charge on these substances is concerned. By
studying ihe electrica l charge e ffe c ts, through measurements
of the electrophoretic mobility of the p articles, it was be­
lieved that a knowledge could be obtained, not only of the
actual magnitude of the electrical charge, but also of the-
manner in riiich th is charge was modified by the presence of
detergents. Moreover, it was thought to be possible to modify
the properties of the detergent solution, with a subsequent
m odification of the electrica l charges cf the dispersed p arti­
cles, in such a way as to produce optimum conditions for th e
removal of so il from te x tile fib ers, if the effects of deter­
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gents on the m obility of fib ers and of oarbon p a rtic le s were
known.
/
Moyer ( 19) stated that the measurement of th e e le c tro ­
phoretic m obilities of suspended p a rtic le s is the sim plest,
most d ire c t, and most satisfacto ry method of evaluating th e
charge on the surface of dispersed p a rtic le s . In th is
study, therefore, electrophoretic m o b ilities were measured
and the values obtained were then re la te d to the charge on
the dispersed p a rtic le s through the following relatio n sh ip ,
which was f i r s t introduced by Helmholtz ( 10), and was modified
by Debye and Huckel (5 ), and Henry ( ll) .
« = I f n
where: 3. = electro k in etic p o ten tial;
D z. d ie le c tric constant of the adsorbed layer;
X = fie ld strength;
= v isco sity of th e medium;
Ac = electrophoretic m obility.
In using th is formula fo r a given set of dispersions,>< , the
m obility, is nearly equal to a constant times th e electro -
k in etic or zeta p o te n tia l, since Ihe d ie le c tric constant and
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v isco sity of dispersions of th e type studied are almost inde­
pendent of the concentration of dissolved solute so long as
i t s concentration is small. The m o b ilities are expressed in
terms of microns per second per u n it of p o ten tial gradient.
Because of the d iffic u lty of evaluating the d ie le c tric con­
3
stant, the electrokinetics p oten tial was not calculated and
m ob ilities were taken as direct measures of the electrokinetio
p oten tials. This was in accordance with ihe practice suggest­
ed by Moyer (19), and by Heniy (1 1 ), and it is follow ed by
nearly a ll investigators in th is fie ld .
The study of which this is a report is divided into two
parts, as follow s: Part I deals with a study of aqueous de­
tergent systems; Part II is a study of non-aqueous detergent
systems.
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P A R T I
E L E C T R O P H O R E T I C M O B I L I T I E S
OP C O T T O H A N D OP C A R B O H
P A R T I C L E S I H A Q, U E 0 U S
S O L U T I O H S