Investigation of Adsorption Characteristics of Sodium Lignosulfonate

Subscriber access provided by UNIV OF NEBRASKA - LINCOLN

Article

Investigation of Adsorption Characteristic of Sodium Lignosulfonate on the Surface of Disperse Dye Using Quartz Crystal Microbalance-Dissipation Yanlin Qin, Xueqing Qiu, Wanshan Liang, and Dongjie Yang Ind. Eng. Chem. Res., Just Accepted Manuscript • DOI: 10.1021/acs.iecr.5b03582 • Publication Date (Web): 20 Nov 2015 Downloaded from http://pubs.acs.org on November 29, 2015

Just Accepted “Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted online prior to technical editing, formatting for publication and author proofing. The American Chemical Society provides “Just Accepted” as a free service to the research community to expedite the dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been fully peer reviewed, but should not be considered the official version of record. They are accessible to all readers and citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors or consequences arising from the use of information contained in these “Just Accepted” manuscripts.

Industrial & Engineering Chemistry Research is published by the American Chemical Society. 1155 Sixteenth Street N.W., Washington, DC 20036 Published by American Chemical Society. Copyright © American Chemical Society. However, no copyright claim is made to original U.S. Government works, or works produced by employees of any Commonwealth realm Crown government in the course of their duties.

Page 1 of 28

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Industrial & Engineering Chemistry Research

Investigation of Adsorption Characteristic of Sodium Lignosulfonate on the Surface of Disperse Dye Using Quartz Crystal Microbalance-Dissipation Yanlin Qin1, Xueqing Qiu1,2*, Wanshan Liang1, DongjieYang1,2* 1

School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, Guangdong, 510640, China. 2

State Key Lab of Pulp and Paper Engineering, South China University of Technology,

Guangzhou, Guangdong, 510640, China. * (X.Q.) Tel.: +862087114722 ; Fax: +862087114721; E-mail: [email protected] ; (D.Y.) E-mail:[email protected]. ABSTRACT: Lignosulfonates obtained from pulping spent liquor is a nontoxic and renewable polymer with excellent dispersability as disperses dye dispersant. In order to reveal its dispersion mechanism on dye, the adsorption characteristics of sodium Lignosulfonate (NaLS) and sodium naphthalene sulfonic acid formaldehyde (NSF) were investigated using a quartz crystal microbalance with dissipation (QCM-D) and an atomic force microscope (AFM). The results show that the adsorption of dispersant onto dye film layer was low and unstable without salt, but the adsorption amount of NaSL or NSF onto dye film was increased significantly with the increasing in ionic strength. This indicates that hydrophobic effect was the main interaction between dispersant and dye. The adsorption amounts of both two dispersants were decreases with the increasing in temperature. NaLS exhibited the better dispersion and improved stability at high temperature than that of NSF due to higher adsorption amount and the viscoelastic adsorption layer. Keywords: Dye dispersant; Disperse dye; QCM-D; AFM; Ionic strength; Temperature.

1. INTRODUCTION Disperse dyes is applied in the dyeing and printing industry in large quantities. Because of its

ACS Paragon Plus Environment


1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

low solubility in water, dispersants are essential for obtaining stable suspensions for successful forming of components with high homogeneity in aqueous dyeing process. In general, commercial disperse dyes are applied by adding 75% to 200 % dispersants based on the weight of dried dye cake to obtain dye bath by grinding or milling1. Willerich2 and Kissa3 reported that the smaller the particles of dye in suspensions, the better the dyeing quality can result when the dye is dispersed. Particularly, the disperse dyes with dispersants in dye bath must exhibit an excellent stability under high temperatures in dyeing process4. At present, the most commonly used dye dispersant is lignosulfonates (LS) and naphthalene sulfonate formaldehyde condensates (NSF). The dispersants aid the wetting of disperses dye particles with water by adsorption onto dye surface to facilitate breaking of dye particle agglomerates for stabilization in water by forming a steric barrier, an electrostatic repulsion5 or DVLO interaction6. LS are mainly obtained from pulping spent liquor and have an obvious advantage of excellent dispersion performance7, 8. The superior disperse performance of LS as dye dispersant was determined by the behavior and the conformation of LS adsorbed onto the dye surface. Therefore, the investigation of the adsorption characteristics of LS on dye has both theoretical significance and application value. A large number of studies on adsorption of lignin onto solid particles have been carried out. Andersson9 studied the removal of lignin from wastewater and measured the adsorption of lignin material onto activated charcoal and fly ash by UV absorption. Ratinac10 investigated the

adsorption mechanisms of lignosulfonate (as dispersant or binder used

widely in ceramic processing) on lead zirconate titanate powder in water using UV spectroscopy. The study proposed that a significant component of the overall driving force of


Page 2 of 28

Page 3 of 28

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


the adsorption was not electrostatic bonding at all pH values examined, and electrostatic bonding provided a contribution to adsorption at pH 6.0 owing to lignosulfonate (negative) ionization. Our previous research11 also found that the dispersion efficiency of LS for Al2O3 particles was influenced by adsorption behavior, and the adsorption characteristics of LS at different pH was investigated by means of UV-Vis spectroscopy and X-ray photoelectron spectroscopy. Our results showed the main driving force of LS adsorbed onto Al2O3 particles was the synergistic effect of the electrostatic interaction and the metal cation- π interaction. Deng

et al12 investigated

the adsorption

behaviors

of

LS onto

the

LS/poly

(dimethylammomium chloride) multilayer and proposed that adsorption process was controlled by electrostatic attraction, hydrophobic interaction and changes in the microstructure, which depended on solution pH. The residual concentration methods are usually used to characterize the adsorption capacity of dispersant on the solid particles via UV-Vis spectroscopy. However, there are some drawbacks using the residual concentration method to determine the adsorption capacity of dispersant on dye particles. Because a considerable portion of disperse dye, which particles size are less than 1 µm, are difficult to be separated from solution. This results in an increase of test error. More importantly, it is difficult to accurately monitor the adsorption conformational changes of the adsorbed layer using traditional methods. So it is very important to develop a new method to test the adsorption characteristics of dispersant onto the dye in order to reveal the action mechanism of dispersant. In recent years, the quartz crystal microbalance with dissipation (QCM-D) technique was gradually used for studying the adsorption of dispersant onto solid surfaces. QCM-D is a



1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

sensitive mass sensor (nanogram level) with advantages such as good surface selectivity and real-time monitoring, and the technique is able to give information not onlythe amount of surface adsorption but also viscoelastic nature of the adsorption layer. Renneckar13 determined the adsorption of alkali lignin onto gold coated crystals treated with a cationic polymer by using a QCM-D. Rahikainen14 used QCM-D to research the adsorption of cellulose on modified lignin and lignosulfonate to reveal the effects of lignin on cellulose enzymolysis. Palmqvist15 studied the adsorption behavior of LS onto alumina surfaces using QCM-D. Norgren16 sutdied the the adsorption of polyallylamine (PAH), poly (acrylic acid) (PAA) and polyelectrolyte complexes (PECs) onto the lignin model film was monitored using QCMD, and their results showed that the high adsorption of PAA and the anionic PAA-PAH polyelectrolyte complex points on lignin films at the presence of strong nonionic interactions. In spite of a large number of studies conducted in the past, the mechanism of adsorption of LS onto dye is not yet well-understood. In the present work, we developed a method of using QCM-D and AFM technique to study the adsorption characteristics of sodium LS on the disperse dye surface. In addition, the effect of ionic strength and temperature on adsorption were investigated to reveal the dispersion mechanism of LS on dye particles

2. MATERIALS AND METHODS 2.1. Materials The disperse dye, disperse Blue 79 (azo dye, C24H27BrN6O10, CAS registry number: 12239-34-8 3618-73-3, the purity is 98%, Zhejiang Runtu Co., Zhejiang, China). The BET surface area of dye powder was 14.052 m2·g-1, and total pore volume was 0.060 cm3·g-1 (N2


Page 4 of 28

Page 5 of 28

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


adsorption, Micromeritics ASAP2010, USA).

Sodium lignosulfonate (NaLS) (Borregaard

Co., Sarpsborg, Norway), which purity was 95%, less than inorganic salts and other components were reductive substances. Sodium Naphthalene sulfonate formaldehyde condensate (SNF) (Shangyu Wencai Co., Zhejiang, China) and its purity was more than 90%, less than 1% sodium sulfate and others were calcium salt, magnesium salt. The characters of NaSL and SNF molecular were list in Table 1, where the molecular weight distribution of dispersants were determined byaqueous gel-permeation chromatography (GPC) with the Waters 2487 UV absorbance detector (Waters Crop., Milford, MA, USA), and the polystyrene sulfonate was used as the standard and 0.1 mol/L NaNO3 solution was used as the mobile phase, the sulfonic group content was determined by the potentiometric titration in an automatic potentiometric titrator (809 Titrando, Metrohm Corporation, Switzerland) with 0.05~0.10 mol·L-1 NaOH as titrant at 25℃ 17. The OHphen content was measured used FC-reagent method through a duplicate UV-Vis measurement at 760 nm18.

2.2. Scanning electron microscope (SEM) images and particle size test 7.5 g of dried dispersant, 5 g of dried dye filter cake, 200 g agate beads and distilled water were mixed in an agate jar in planetary ball mill (QM-3SP2, Nanjing University Instrument Co., Nanjing, China). The solid content of mixture was adjusted to 30 wt% with distilled water and the pH was adjusted to 5.5 with HAc/NaAc before milling. The dispersant-dye suspension was obtained by milling 4 h. The suspension was diluted to 0.1% with distilled water and adjusted pH to 5.5 with HAc/NaAc solution. Then, some of diluted suspension was heated to 130℃(the dyeing temperature) keeping 30 min. The SEM images of dispersant-dye suspension were recorded with a Nova Nano SEM instrument (Zeiss



1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Netherlands BV, Sliedrecht, Netherlands). The particle size of diluted suspension was determined by a laser particle analyzer (EyeTech-Laser, Ankersmid Corp., Nijverdal, TheNetherlands).

2.3. Preparation of dye film New gold covered electrode plate QCM-D crystals were used for experiments. They were cleaned by immersing in a 5:1:1 mixture of ultrapure water, hydrogen peroxide (30%) and ammonium hydroxide (25%)for 10 min in a controlled temperature of 75 ℃ using a cleaning holder. After rinsed thoroughly with Milli-Q water, they were exposed to pure nitrogen gas to dry. Acetone used as the best solvent to prepare uniform C.I. disperse blue 79 films19, 20 by spin coating. Dissolved C.I. disperse bule 79 in acetone with concentration of 10.0 g·L-1 and stirred 30 min, the solution was used to prepare dye films by a spin-coater (WS-400Bz-6NPP-LITE, Mycro Technologies Corp., Shanghai, China)21, 22. The procedure is shown in Figure 1. Putting the cleaned gold electrode plate on the center of spin coating, then the spin coating was carried out in four steps17: 1000 rpm for 15 s, 2000 rpm for 60 s , 900 rpm for15s and 5 for stop. Prepared disperse dye films were carefully washed by ultrapure water and dried by a stream of nitrogen gas and then dried again in fume cupboard for 3h to evaporate acetone at room temperature . 2.4. QCM-D Measurements The adsorption experiments were performed using a Q-SenseE1 instrument (Q-Sense AB Corp., Sweden). The third overtone of the frequency shift (Δf)and the third overtone of the shift in dissipation (ΔD) was used to represent the adsorption mass23, 24 (the dispersants


Page 6 of 28

Page 7 of 28

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


absorbed on dye) and viscoelasticity of the adsorbed layer25, respectively. 2.4.1. Determination of adsorption of Dispersant on the dye The concentration of dispersant in solutions was 0.5 g·L-1 (pH=5.5, adjusted by acetic acid). The cell of QCM-D was initially rinsed in water (pH=5.5, adjusted by acetic acid) until a stable baseline was established, then rinsing in anionic dispersant solution and pressing restarted. Measurement data forΔf andΔD were acquired, the velocity of peristaltic pump was maintained at 0.100 mL/min. All measurements were performed at a temperature of 25℃. The process is shown as Figure 1. 2.4.2. Determination of adsorption of dispersant on dye with NaCl 0.5 g·L-1 of dispersant solutions with the addition of NaCl ranging of 0.25 mol·L-1, 0.5 mol·L-1, 1.0 mol·L-1 were prepared (adjust pH=5.5 by acetic acid), and correspond to prepare 0.25 mol·L-1, 0.5 mol·L-1, 1.0 mol·L-1 NaCl solution (adjust pH=5.5 by acetic acid)as buffer solution. The cell of QCM-D was initially rinsed in NaCl solution until a stable baseline was established before rinsing in dispersant and NaCl mixture solution. The velocity of peristaltic pump was maintained at 0.100 mL/min.Δf andΔD were measured, and the temperature was ranged of 25℃. 2.4.3. Determination of adsorption at different temperature 0.5 g·L-1 of dispersant solutions with the addition of 0.5 mol·L-1 NaCl(adjust pH=5.5 by acetic acid) were prepared, and correspond to prepare 0.25 mol·L-1, 0.5 mol·L-1, 1.0 mol·L-1 NaCl solution (adjust pH=5.5 by acetic acid) as buffer solution. Temperature increased from 20℃ to 45℃ and then decreased to 20℃, kept for 20 min at per increased or decreased 5℃, and the rate of temperature change is 0.25℃·min-1. The method of measurement ofΔf and



1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

ΔD as 2.3.2. 2.5. Atomic force microscopy (AFM) AFM images and root mean square roughness (RMS) of the adsorbed films were obtained by using a noncontact-mode atomic force microscopy (XE-100, Park Systems Corp., Korean) with PPP-NCHR silicon cantilevers at 25℃.All images presented are height images and have been zero-order flattened using a standard algorithm within the XEI software to remove the artificial height offsets between consecutive scan lines of the raw images.

3. RESULTS AND DISCUSSION 3.1. Dispersity of the dispersants on dispersed dye In order to reveal the effect of dispersant adsorption on its dispersion performance, the SEM and particles size analysis for disperse dye suspension were carried out. The results are shown in Figure 2. From Figure 2 A and B, the shape of disperse dye in suspension added NaLS and NSF were both flake. At 25℃, the dye size added NaLS and NSF both are approximate less than 1.0 µm from Figure 2 E, and the dye particles were uniformly dispersed in the suspension with very few accumulation or aggregation, indicating that NaLS and NSF both possessed good dispersability at 25℃. At 130℃, dye particles in dye suspension with NaLS and NSF however were aggregated even with both dispersants (Figure 2 C and D). The shape of dye particles with NaLS as dispersant looks like rods with an average particle size around 22.21 µm. Dye particles with NSF as dispersant appeared in irregular floccus with a greater average particle size of 79.78 µm. This suggests that the dispersion stability of NaLS under high temperature is superior to that of NSF. 3.2. The adsorption of dispersant adsorb on dye


Page 8 of 28

Page 9 of 28

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


The adsorption curves of NaLS and NSF onto dye surface from the quartz crystal are shown in Figure 3. The higher value of |∆f| represents a greater adsorbed amount. From Figure 3, |∆fNaLS| was approximately 7.0 Hz, and |∆fNSF| was approximate 5.3 Hz. Both adsorbed amounts for NaLS and NSF were little and unstable onto dye. It can be seen that the value of ∆D, which characterizes the viscoelastic or stiffness properties of adsorbed layer, was also fluctuant and instable. It was not possible to characterize the viscoelastic nature of the adsorbed layer using the data in Figure 3. This phenomenon was observed in adsorbing lignosulfonate onto hydrophobic interface15. This will cause relatively great errors in the determination of the adsorption characteristics. According a literature study26, the sulfonic acid group in NaLS and NSF can be ionized at pH 2-12. The ionization of hydrophilicity group would significantly increase the thickness of electric double layer between dispersants to result in an unstable adsorption layer and reduction of dispersant adsorption amount

27

. The adsorption amount can increase by

increasing of a solution ionic strength, because salt can screen the charges, compression electric double layer and inhibit the Coulomb interactions in polyelectrolytes, so as can enhance dispersant adsorb on the disperse dye surface26, 27. The commercial dye dispersants and dye bath contain a large amount of inorganic salt. It will be of more interesting to study the adsorption characteristics of dye dispersants under different ionic strengths. As shown in Figure 4 (a), |∆f| values for both NaLS and NSF were increased with the increasing in ionic strength, indicating increased the adsorption amounts. This related to NaCl can shield electrostatic interaction of sulfonic group in NaLS or NSF molecules. It can also be found that the |∆f| for NaLS is higher than that for NSF at the same ionic strength,



1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

indicating more NaLS adsorb onto dye than NSF. Although the amounts of absorption of two dispersants were different at 25℃ (Figure 2 A and B), good dispersion of dye were achieved using both dispersants. The higher molecular weight and greater amount of adsorption of NaLS can form a stronger steric hindrance. Although NSF has a lower molecular weight and lower adsorption amount but it has more sulfonic groups that can provide stronger static repulsion than that of NaSL. The result in Figure 3 indicates that a dispersant with higher molecular weight or higher sulfonic groups can provide good dispersion. ∆D related to viscoelastic properties, the smaller ∆D shows the smaller viscoelasticity and greater rigid of adsorbed layer, and the higherΔD indicates the bigger viscoelasticity and thickness of adsorbed layer28, 29. ∆D for NaLS and NSF had a significant and slight increase respectively with increasing in ionic strength. The increasing ∆D for NaLS may due to the formation of thicker layers of NaLS and the increased flexibility of its three-dimensional molecules. Additionally, because the QCM-D response of ∆f and ∆D at 0.5 mol·L-1 NaCl were stable and moderate, so this conditions were chosen for subsequent research. An indication of the properties of the dispersant adsorption layer can be achieved by looking at the dissipation per frequency. In order to observe the changes intuitively, the dissipation versus the change infrequency is plotted in Figure 4 (b), what’s more, theΔD/Δf curves were fitted to a straight line to give further insight into the adsorption characters of the layer. A steeper |∆D/∆f| value (the absolute value of fitted curve’s slope) means a more dissipative layer per frequency, which supports the idea that the conformation of the dispersant adsorption layer is softer and more viscoelastic15, 30. On the contrary, a low slope value means mass addition without significant dissipation increase, which states the adsorbed


Page 10 of 28

Page 11 of 28

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


dispersant layer is a rigid and homogeneous structure15, 30. With the increasing of ionic strength, |∆D/-∆f| values for NaLS increased gradually, which signals that NaLS has a soft, dissipative layer. The inconspicuous change in the |∆D/-∆f| values for NSF with increasing in ionic strength manifests that the soft of the adsorbed layers have no obvious increase. This may due to the thin layers and linear-chain molecules of NSF. Moreover, the value |∆D/-∆f| for NaLS is greater than that for NSF at the same ionic strength, which further stated that the adsorption layer of NaLS onto dye is a thick, viscous layer compare with NSF15. 3.3. The effect of temperature on adsorption Dye bath is often cycled between a temperature range through heating and cooling during dyeing process. Dispersant adsorption study was therefore carried out with temperature ramping from 20 to 45℃, then cooling to 20℃. Under NaCl concentration 0.5 mol·L-1, adsorption of NaCl onto the dye was first measured before adding dispersant by QCM-D. The frequency shift (∆fT-NaCl) and the shift dissipation (∆DT-NaCl) of NaCl were shown in Figure 5. |ΔfT-NaCl| value followed the temperature profile while ∆DT-NaCl value behaved opposite to the trend of temperature as a result of the change of the density and viscosity of the aqueous solution at different temperature31. Finally,ΔfT-NaCl and ∆DT-NaCl return to the initial value at the end of the process, so dye film is not influenced by NaCl aqueous solution during temperature cycling. The value of |ΔfT-NaLS| was 21.7 Hz and |ΔfT-NSFl| was 18.2 Hz at the first adsorption equilibrium at 20℃, which means the initial adsorption amount of NaLS on the dye was higher than NSF. The result is consistent with Figure 4(a). At the highest maximal 45 ℃,



1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

|ΔfT-NaLS| value was a little lower than |ΔfT-NaCl|, indicating a certain amount of NaLS adsorb onto dye. |ΔfT-NSF| value is higher than |ΔfT-NaCl|, indicating the adsorption amount of NSF on dye decrease, even a part of dye may desorb from gold electrode plate. As temperature decreased from 45℃ to 20℃, the amount of dispersant adsorbed onto dye was increased gradually. At 20℃(160 min), |ΔfT-NaLS| was approximately 21.4 Hz, which closed to the initial value of 21.7 Hz. However, |ΔfT-NSF| was 15.7 Hz at final 20℃, which was difference from the initial value of 18.2 Hz. The greater change indicated NSFdye system was greatly influenced by the high temperature. The tiny change of adsorption amount stated the stability of the NaLS-dye system was better at a higher temperature. AFM test was carried out to provide further analysis of the temperature effect on adsorption of dispersant. The AFM images of the adsorbed layer at 20℃ for 20 min, 45℃ for 80 min, 20℃ for 160 min are shown in Figure 6. The changes in the observed structures from these images were further numerically analyzed using the root mean square roughness (RMS) for each image. The results are listed in Table 2. From Figure 6 A and D, the dye surface was well attached and uniformly covered by NaLS and NSF at 20℃, respectively. RMS value of NaLS adsorbed layer was slightly larger than that of NSF. A large number of rough structures of NaLS and NSF adsorbed films became clearly visible at 45℃ from Figure 6 B and E. The RMS of NSF was significantly increased with the increase in temperature. The TEM images of Figure 2 illustrated that the dye particles aggregated at high temperatures. Particularly, the average dye size particles with NSF demonstrated its poor dispersability and stability at high temperature. The RMS of NaLS was appears increased from 2.03 nm to 3.79 nm when temperature raised from 20 to


Page 12 of 28

Page 13 of 28

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


45℃, which smaller than NSF at the same temperature increment. The higher hydrophobic adsorption lead to better high temperature stability, greater adsorption amount and more stable adsorption layer. RMS of NaLS was decreased to 1.88 nm and its adsorbed layer onto dye became dense again (Figure 6 C) when temperature fell to 20℃. This was because the adsorption amount was restored to the initial adsorption amount (Figure 5). RMS of NSF was 16.06 nm at 20℃ (160 min, Figure 6 F ), and the adsorption layer was still more coarser than that at 20℃(20 min). This related to the poor dispersability and stability of NSF at high temperature, which may made a portion of dye desorbed from gold surface composed with NSF. So it leaded to the adsorption amount can’t back to initial value. 3.3. The adsorption model of NaLS and NSF on disperse dye. The disperse Blue 79 structures is similar to monomers of polymer with hydrophobic structure, containing benzene rings, azo, acetamide and ethoxyphenyl and so on. The BET surface area and pore volume (Materials section) of dye suggested it is not loose structure. The adsorption amount increased with the increase in salt (Figure 4 a), indicating that the hydrophobic interaction was the main driving force between dye surface and dispersant. ∆D versus ∆f plot are all straight linear or approximately linear (Figure 4 b), which is indicative of a single layer adsorption of NaLS and NSF onto the dye surface26. In our previous study12,

26

, NaLS with high molecular weight could strongly adsorb on the

hydrophobic surface by hydrophobic effect. The NaSL molecules is a three-dimensional net structure32. Salt can cause NaLS molecular conformation shrinkage and crimp33. So its molecular conformation appears curly and the single adsorption exhibits a viscoelastic, soft



1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

layer. The molecular configuration of NSF is a linear structure with the main chain of aromatic ring34. The adsorption is a thin and low viscoelastic (Figure 4). The adsorption amount of NaLS was higher than NSF especially at high temperature (Figure 5 and 6). The layer of NSF is a thin, single and parallel adsorption onto dye surface. The adsorption models of NaLS and NSF onto disperse dye surface are shown in Figure 7 based on the above investigation.

4. CONCLUSION The adsorption characteristic of sodium lignosulfonate and sodium naphthalene sulfonic acid formaldehyde condensation adsorb onto disperse dye was studied out using QCM-D and AFM. The adsorption amounts of both two dispersants increased with the increasing of ionic strength, and decreased with the increasing of temperature. Comparing with NSF, NaLS had higher adsorption with viscoelastic behavior on dye to exhibit better dispersability and stability at high temperature. Notes The authors declare no competing financial interest

ACKNOWLEDGMENTS The authors would like to acknowledge the financial support of International S&T Cooperation Program of China (2013DFA-41670), National Natural Science Foundation of China (21436004, 21576106) and the Fundamental Research Funds for the Central Universities (2014ZP0003).

REFERENCES


Page 14 of 28

Page 15 of 28

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


(1) Dilling, P.; Samaranayake, G. S. Mixtures of amine modified lignin with sulfonated lignin for disperse dye. U.S. Patent 5,989,299, 1999. (2) Willerich, I.; Li, Y.; Gröhn, F. Influencing Particle Size and Stability of Ionic Dendrimer Dye Assemblies. J. Phys. Chem. B 2010, 114, 15466. (3) Kissa, E. Partitioning and Stability of Aqueous Dispersions. Particle Size of Dye Dispersions. Langmuir 1990, 6, 478. (4) Dilling, P. Effect of Cation Type on Lignosulfonate Dispersant Performance in Disperse Dye Systems. Text. Chem. Color. 1988, 20, 17. (5) Kissa, E. Partitioning and Stability of Aqueous Dispersions. Effect of Electrolytes on the Stability of Aqueous Dye Dispersions. Langmuir 1990, 6, 1217. (6) Melis, S.; Verduyn, M.; Storti, G.; Morbidelli, M.; Bałdyga, J. Effect of Fluid Motion on the Aggregation of Small Particles Subject to Interaction Forces. AIChE J. 1999, 45, 1383. (7) Teng, N.-Y.; Dallmeyer, I.; Kadla, J. F. Effect of Softwood Kraft Lignin Fractionation on the Dispersion of Multiwalled Carbon Nanotubes. Ind. Eng. Chem. Res. 2013, 52, 6311. (8) Norgren, M.; Mackin, S. Sulfate and Surfactants as Boosters of Kraft Lignin Precipitation. Ind. Eng. Chem. Res. 2009, 48, 5098. (9) Bai, B.; Wu, Y.; Grigg, R. B. Adsorption and Desorption Kinetics and Equilibrium of Calcium Lignosulfonate on Dolomite Porous Media. J. Phys. Chem. C 2009, 113, 13772. (10) Ratinac, K.; Standard, O.; Bryant, P. Lignosulfonate Adsorption on and Stabilization of Lead Zirconate Titanate in Aqueous Suspension. J. Colloid Interface Sci. 2004, 273, 442. (11) Li, R.; Yang, D.; Guo, W.; Qiu, X. The Adsorption and Dispersing Mechanisms of Sodium Lignosulfonate on Al2O3 Particles in Aqueous Solution. Holzforschung 2013, 67, 387. (12) Deng, Y.; Wu, Y.; Qian, Y.; Ouyang, X.; Yang, D.; Qiu, X. Adsorption and Desorption Behaviors of Lignosulfonate During the Self-Assembly of Multilayers. BioResources 2010, 5, 1178. (13) Pillai, K. V.; Renneckar, S. Cation-Π Interactions as a Mechanism in Technical Lignin Adsorption to Cationic Surfaces. Biomacromolecules 2009, 10, 798. (14) Rahikainen, J. L.; Martin-Sampedro, R.; Heikkinen, H.; Rovio, S.; Marjamaa, K.; Tamminen, T.; Rojas, O. J.; Kruus, K. Inhibitory Effect of Lignin During Cellulose Bioconversion: the Effect of Lignin Chemistry on Non-Productive Enzyme Adsorption. Bioresour. Technol. 2013, 133, 270. (15) Palmqvist, L.; Holmberg, K. Dispersant Adsorption and Viscoelasticity of Alumina Suspensions Measured by Quartz Crystal Microbalance with Dissipation Monitoring and in Situ Dynamic Rheology. Langmuir 2008, 24, 9989. (16) Norgren, M.; Gärdlund, L.; Notley, S. M.; Htun, M.; Wågberg, L. Smooth Model Surfaces from Lignin Derivatives. II. Adsorption of Polyelectrolytes and Pecs Monitored by QCM-D. Langmuir 2007, 23, 3737. (17) Lou, H.; Lai, H.; Wang, M.; Pang, Y.; Yang, D.; Qiu, X.; Wang, B.; Zhang, H. Preparation of Lignin-Based Superplasticizer by Graft Sulfonation and Investigation of the Dispersive Performance and Mechanism in a Cementitious System. Ind. Eng. Chem. Res. 2013, 52, 16101. (18) De Sousa, F.; Reimann, A.; Björklund Jansson, M.; Nilberbrant, N. Estimating the Amount of Phenolic Hydroxyl Groups in Lignins(P173). In 11th International Symposium on



1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Wood and Pulping Chemistry, Nice, France, 2001, 3, 649. (19) Gharanjig, K.; Sadeghi-Kiakhani, M.; Tehrani-Bagha, A.; Khosravi, A.; Menger, F. Solubility of Two Disperse Dyes Derived from N-Alkyl and N-Carboxylic Acid Naphthalimides in the Presence of Gemini Cationic Surfactants. J. Surfactants Deterg. 2011, 14, 381. (20) Huang, G.; Dai, J.; Dong, F.; Wang, J.; Jia, Y. Compatibility of a Disperse Dye Mixture in Supercritical Carbon Dioxide Dyeing. Color. Technol. 2013, 129, 305. (21) Natsume, Y.; Sakata, H. Zinc Oxide Films Prepared by Sol-Gel Spin-Coating. Thin Solid Films 2000, 372, 30. (22) Norgren, M.; Notley, S. M.; Majtnerova, A.; Gellerstedt, G. Smooth Model Surfaces From Lignin Derivatives. I. Preparation and Characterization. Langmuir 2006, 22, 1209. (23) Rodahl, M.; Höök, F.; Fredriksson, C.; Keller, C. A.; Krozer, A.; Brzezinski, P.; Voinova, M.; Kasemo, B. Simultaneous Frequency and Dissipation Factor QCM Measurements of Biomolecular Adsorption and Cell Adhesion. Faraday Discuss. 1997, 107, 229. (24) Plunkett, M. A.; Claesson, P. M.; Rutland, M. W. Adsorption of a Cationic Polyelectrolyte Followed by Surfactant-Induced Swelling, Studied with a Quartz Crystal Microbalance. Langmuir 2002, 18, 1274. (25) Richter, R.; Mukhopadhyay, A.; Brisson, A. Pathways of Lipid Vesicle Deposition on Solid Surfaces: a Combined QCM-D and AFM Study. Biophys. J. 2003, 85, 3035. (26) Ouyang, X.; Deng, Y.; Qian, Y.; Zhang, P.; Qiu, X. Adsorption Characteristics of Lignosulfonates in Salt-Free and Salt-Added Aqueous Solutions. Biomacromolecules 2011, 12, 3313. (27) Boehm, H. Some Aspects of the Surface Chemistry of Carbon Blacks and other Carbons. Carbon 1994, 32, 759. (28) Höök, F.; Kasemo, B.; Nylander, T.; Fant, C.; Sott, K.; Elwing, H. Variations in Coupled Water, Viscoelastic Properties, and Film Thickness of a Mefp-1 Protein Film during Adsorption and Cross-Linking: A Quartz Crystal Microbalance with Dissipation Monitoring, Ellipsometry, and Surface Plasmon Resonance Study. Anal. Chem. 2001, 73, 5796. (29) Malmström, J.; Agheli, H.; Kingshott, P.; Sutherland, D. S. Viscoelastic Modeling of Highly Hydrated Laminin Layers at Homogeneous and Nanostructured Surfaces: Quantification of Protein Layer Properties Using QCM-D and SPR. Langmuir 2007, 23, 9760. (30) Feiler, A. A.; Sahlholm, A.; Sandberg, T.; Caldwell, K. D. Adsorption and Viscoelastic Properties of Fractionated Mucin (BSM) and Bovine Serum Albumin (BSA) Studied with Quartz Crystal Microbalance (QCM-D). J. Colloid Interface Sci. 2007, 315, 475. (31) Ishida, N.; Biggs, S. Direct Observation of the Phase Transition for a Poly (N-Isopropylacryamide) Layer Grafted onto a Solid Surface by AFM and QCM-D. Langmuir 2007, 23, 11083. (32) Lin, S. Y.; Dence, C.W. Methods in Lignin Chemistry; Springer-Verlag: Berlin, 1992. (33) Deng, Y.; Feng, X.; Zhou, M.; Qian, Y.; Yu, H.; Qiu, X. Investigation of Aggregation and Assembly of Alkali Lignin Using Iodine as a Probe. Biomacromolecules 2011, 12, 1116. (34) Yang, D.; Qin, Y.; Du, Y.; Zheng, D. Adsorption Characteristics of Naphthalene Sulfonate Formaldehyde Condensate with Different Molecular Weights. J. Dispersion Sci. Technol. 2013, 34, 1092.


Page 16 of 28

Page 17 of 28

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


LIST OF TABLES

Table 1. Molecular weight distribution and functional group of NaLS and SNF Table 2. RMS of adsorption layer of NaLS and NSF on dye film



1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

LIST OF FIGURES

Figure 1. The test process of dispersants adsorb on dye by QCM-D. Figure 2. SEM images of dye particles with dispersant. (A) Dye particles with NaLS at 25℃; (B) dye particles with NSF at 25℃; (C) dye particles with NaLS at 130℃; (D) dye particles with NSF at 130℃; (E) dye particles size in suspension at 25 and 130 °C. Figure 3. Frequency shift and Dissipation change as a function of time during adsorption of (a)NaLS ; (b) NSF on dye Figure 4. (a) Frequency shift and Dissipation change as a function of time during adsorption of dispersants on dye with different concentration NaCl;(b) Frequency shift versus Dissipation change of dispersants adsorb on dye (The legend means the concentration of added NaCl in dispersant aqueous solution, e.g. ‘NaLS-0.25 M NaCL ’ means added 0.25 mol·L-1 NaCl in NaLS aqueous solution.). Figure 5. Frequency shift and Dissipation change as a function of time during adsorption of NaCl aqueous solution, NaLS and NSF with NaClon dispersedye with by stage temperature process (The legend means the dispersant aqueous solution, e.g. ‘ΔfT-NSF ’ means the frequency shift of NSF aqueous solution with 0.5 mol·L-1 NaCl.). Figure 6. AFM images of dispersant absorbed on dye at different temperature from Fig.5. (A) NaLS absorb on dye at 20℃ (20 min), (B) NaLS absorbed on dye at 45℃ (80 min), (C) NaLS absorbed on dye at 20℃ (160 min), (D) NSF absorbed on dye at 20℃ (20 min), (E) NSF absorbed on dye at 45℃ (80 min) and (F) NSF absorbed on dye at 20℃ (160 min). Figure 7.

Adsorption model of NaLS and NSF onto dye surface.


Page 18 of 28

Page 19 of 28

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


Table 1. Molecular weight distribution and functional group of NaLS and SNF.

OHphen

(mmol·g )

sulfonic group (mmol·g-1)

2.14

1.88

1.56

1.54

—

2.15

Samples

Mw(Da)

Mn(Da)

Mw/Mn

NaLS

10,250

4,780

SNF

6,100

3,950

-1



1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Table 2. RMS of adsorption layer of NaLS and NSF on dye film. RMS (nm) of layer Dispersants

20 min (25℃)

80min (45℃)

160min (20℃)

NaLS

2.03

3.79

1.88

NSF

1.97

22.35

16.06


Page 20 of 28

Page 21 of 28

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


Figure 1. The test process of dispersants adsorb on dye by QCM-D.



1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Figure 2. SEM images of dye particles with dispersant. (A) Dye particles with NaLS at 25℃; (B) dye particles with NSF at 25℃; (C) dye particles with NaLS at 130℃; (D) dye particles with NSF at 130℃; (E) dye particles size in suspension at 25 and 130 °C.


Page 22 of 28

Page 23 of 28

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


a

b

Figure 3. Frequency shift and Dissipation change as a function of time during adsorption of (a)NaLS ; (b) NSFon dye.



1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

(a）

(b)

Figure 4. (a) Frequency shift and Dissipation change as a function of time during adsorption of dispersants on dye with different concentration NaCl;(b) Frequency shift versus Dissipation change of dispersants adsorb on dye (The legend means the concentration of added NaCl in dispersant aqueous solution, e.g. ‘NaLS-0.25 M NaCL ’ means added 0.25 mol·L-1 NaCl in NaLS aqueous solution.).


Page 24 of 28

Page 25 of 28

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


Figure 5. Frequency shift and Dissipation change as a function of time during adsorption of NaCl aqueous solution, NaLS and NSF with NaClon dispersedye with by stage temperature process (The legend means the dispersant aqueous solution, e.g. ‘ΔfT-NSF ’ means the frequency shift of NSF aqueous solution with 0.5 mol·L-1 NaCl.).



1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Figure 6. AFM images of dispersant absorbed on dye at different temperature from Fig.5. (A) NaLS absorb on dye at 20℃ (20 min), (B) NaLS absorbed on dye at 45℃ (80 min), (C) NaLS absorbed on dye at 20℃ (160 min), (D) NSF absorbed on dye at 20℃ (20 min), (E) NSF absorbed on dye at 45℃ (80 min) and (F) NSF absorbed on dye at 20℃ (160 min).


Page 26 of 28

Page 27 of 28

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


Figure 7. Adsorption model of NaLS and NSF onto dye surface.



1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

For Table of Contents Only


Page 28 of 28

Investigation of Adsorption Characteristics of Sodium Lignosulfonate

Recommend Documents