Adsorption behavior of surfactant‐polyacrylamide mixtures with kaolin

Abstract

The adsorption behavior of three surfactantshexadecylpyridinium bromide (HPyBr), sodium dodecylbenzene sulfonate (SDBS), and Triton X-100 (TX-100)-on kaolin from aqueous solution is monitored as a function of pH. The nature and shape of the adsorption isotherms are typical and highly dependent on the surfactant structure. All three surfactants adsorb on kaolin beyond the limits of monolayer coverage. Isotherms for HPyBr fit the Langmuir equation well. SDBS isotherms are typical of a two-stage process, and TX-100 adsorption isotherms are Sshaped. The pH-sensitive adsorption of each surfactant and the models used to represent the isotherms are considered together in explaining the mechanism of adsorption in each case. The complex mixture adsorption behavior from polyacrylamide-surfactant mixtures is also determined in acidic and basic pH media. Three polyacrylamides, catam1, anam1 and nonam1, are chosen to represent cationic, anionic, and nonionic polymers, respectively. Both competitive and synergistic effects are noted in the mixture adsorption depending upon the polymer-surfactant pair and the mode of introduction of a second component in the presence of another. The results are explained by considering various factors such as changes in the nature of solvent power of the media, interaction between the polymer and surfactant in the bulk solution as well as at the kaolin surface, blocking of surface sites by a preadsorbed component, and the change in the conformation state of polymer chains Paper no. S1126 in JSD 2, 459-472 (October 1999).KEY WORDS: Adsorption mechanism, competitive and synergistic effects, individual and mixture adsorption, kaolin, polyacrylamides, surfactants.Adsorption of surfactants at the solid-liquid interface is of broad interest in different fields of application, such as ore flotation, tertiary oil recovery, detergents, cosmetics, and pharmaceuticals (1-5). The efficiency of a surfactant in any of these application areas is due to the high surface activity of the surfactant at the solid-liquid interface. Also, loss of surfactants has been reported when they are used in tertiary oil-recovery processes, in which surfactant micellar solutions are injected into the rock formation to release trapped oil. Surfactant loss is traced mainly to its adsorption on to rock formations or other porous solid minerals like clay. Moreover, the surfactants are well-characterized model substances in establishing and understanding their adsorption mechanism on oppositely charged hydrophilic and hydrophobic substrates, oleophobic and uncharged hydrophobic surfaces, etc. Hence, the adsorption studies of surfactants not only are of an academic interest but also have great techno-economic value. Kaolin is a reactive clay mineral and is an important and unique substrate with a capacity to adsorb positively charged, negatively charged, and even uncharged surfactant species. The surface chemistry of kaolin is unique and it is now well known that its surface is heterogeneous in nature and has both cation and anion e...

Static Adsorption and Retention of Viscoelastic Surfactant in Porous Media: EOR Implication

“…The adsorption characteristics of binary or ternary surfactant systems were also previously investigated. The adsorption data of three surfactants on kaolinite indicated that the surfactant structure had a considerable effect on the adsorption isotherms and that competitive and synergistic effects occurred in the surfactant–polyacrylamide system . In addition, when the molar ratio of cationic and anionic surfactant binary systems was >1.1, the adsorption was negligible and the presence of nonionic surfactant impaired the adsorption of the ionic species .…”

Arsenic retention and transport behavior in the presence of typical anionic and nonionic surfactants

“…The adsorption of SDBS could reduce the interfacial tension between FH and water as well as enhance the wettability of the FH surface, promoting the external diffusion of arsenic to the FH surface (Sastry and Dave, 1999;Thibaut et al, 2000;Wang and Kwak, 1999;Yang et al, 2007Yang et al, , 2010. The nonionic surfactant Triton X-100 exerted different impacts on the adsorption kinetics of As(V) and As(III).…”

Fire Performance of Fiber Board Coated with Nano Kaolin-Clay Film

“…The nature and shape of the adsorption isotherms were typically very much dependent on the surfactant structure. All three surfactants adsorbed onto kaolin beyond the limits of a monolayer coverage (Sastry and Dave 1999).…”