Study on Preparation and Performance of High Swelling Bentonite

Abstract

For improving the expansibility of natural Ca-based bentonite (Ca-Bent), the Ca-Bent was modified with sodium dodecyl benzene sulfonate(SDBS)-Na 2 CO 3 complex agent by microwave semi-dry method. And the ratio of Na 2 CO 3 to SDBS, microwave power, radiation time and initial temperature on the modification were studied. Furthermore, X-ray diffraction (XRD) patterns and infra-red spectrum (IR) were carried out to characterize , which obtain microstructure of samples. The result showed that the optimized experimental parameters are obtained as follows: Na 2 CO 3 to SDBS ratio 1:1, radiation time 2min, microwave power 600W and initial temperature 120K. Besides, under the optimization conditions, the modified bentonite has swelling volume of 68.5mL/g, cation exchange capacity of 56.2mmol/10 2 g and yield point and plastic viscosity ratio of 1.67, respectively. A comparison of the single factor experiment and orthogonal experiment indicates that the SDBS and Na 2 CO 3 have synergistic effect in the process of modification, especially, under the optimum microwave condition, Na 2 CO 3 increased the anion activity of SDBS, which enhanced the hydrophilicity of modified bentonite. The experimental result show that the process improves the swelling volume of bentonite and the comprehensive performance. So, the modified bentonite was a perfect additive in water drilling mud.

Research of Na2CO3/C12H25SO4Na modified bentonite on high dispersion performance

“…This is because the reaction process generates a large number of liquid beads in the suspension due to the adhesion of SDBS on the bentonite surface, which produces the Jamin effect. This effect is due to the fact that the generated liquid beads reduce the leakage pore space to stop the filtrate from leaking to the lower layer, thus controlling the filtrate of the working fluid [18].…”

Hydroxyethyl Cellulose Acrylamide Graft Polymer-Bentonite Nanocomposites Synthesis, Characterization and Properties

“…The polymer was successfully intercalated between the bentonite layers under the internal driving force (hydrogen bonding) and external driving force (shearing force). [28] The final choice is to modify the bentonite with a polymer proportion of 5wt%. FT-IR analysis was used to confirm the preparation of HEC-AM/bentonite composite.…”