No abstract

No abstract

No abstract

TWO different superplasticizers particularly Cyclohexanone formaldehyde sulfanilate (CFS) and Cyclohexanone glyoxylic sulfanilate (CGS) were prepared; also, their effect on mechanical and physico-chemical properties of oil well cement was assessed. The chemical structures were affirmed by FTIR technique. The designed chemical compounds were predestined as superplasticizers for cement pastes. The pastes made by superplasticizers (CFS or CGS) addition to cement by the ratios of 0, 0.25, 0.50, 0.75, and l.00 as mass % of cement. The consistence water, setting time, chemically combined water content (Wn), the hydration rate and compressive strength of the admixed hardened pastes were predestined at various time periods. The phase composition was intended by DSC and XRD techniques. The results revealed that as the admixture dose rate increases the demand cement paste water of consistency decreases. Also, as the admixture addition rate increases the chemically combined water content decreases, so the rate of hydration decreases; meanwhile compressive strength magnitudes increase in accounts for the low water/cement (initial porosity) of the sample. The factors affecting the cementing process of oil wells are the temperature, pressure, minerals, impurities and the water/cement ratio (1,2). These factors jointly or individually having a fastening effect on the initial setting time of cement which negatively affects the workability and makes it impossible to pump as a result of the coming down of the cement deep into the ground and this process may take several hours. So begin the use of chemical mixtures (3) , such as superplasticizers, which work to increase fluidity and to facilitate the process of pumping cement slurries to the depths of wells easily with no changing in the cement properties (4). Strong repulsion happens because the superplasticizer and the cement particle's charge by a similar charge (5). Given the large molecular weight of superplasticizers, the plasticizers are also working as pore fillers between the particles of cement which reduces the water/cement ratio and therefore gives a high magnitude compressive strength (6-9). The synthesis processing parameter of water soluble sulfonated cyclohexanone formaldehyde (SCF) superplasticizer has influence on the inherent viscosity and the dispersing

Designating an organic inhibitor with a specific chemical structure that actively participates in steel protection by increasing adsorption on the steel surface. Based on that, we synthesized three zwitterionic surfactants based on azomethine with different hydrophobic chain lengths labeled ZWSO, ZWSD, and ZWSH. The presence of azomethine group, electrons, and heteroatoms in the zwitterionic surfactant’s amphipathic structure helped to improve C-steel protection. Their inhibitory activity toward steel corrosion was investigated utilizing electrochemical impedance spectroscopy (EIS), gravimetrical, and potentiodynamic polarization techniques. Importantly, the surfactant tail influenced corrosion inhibition performance; as surfactant tail length increased, so did inhibition efficiency due to increased adsorption affinity. The inhibition efficiencies of ZWSO, ZWSD, and ZWSH are 87.15, 89.82, and 91.36%, respectively. Tafel data clarified that ZWSO, ZWSD, and ZWSH inhibitors behave as mixed-type inhibitors following the modified Langmuir isotherm. The inhibitors can adsorb physiochemically on the steel surface with ∆G ads ranges from −38.48 to −44.6 kJ mol−1. The SEM confirms that the morphology of C-steel becomes smoother because of inhibitor adsorption. The DFT and MCs output data supported the experimental performance of the tested ZWSO, ZWSD, and ZWSH inhibitors and especially their dependence on surfactant tail length.