The corrosion inhibition of Luffa cylindrica Leaf Extract (LCLE) was investigated using gravimetric, depth of attack and surface analysis techniques. Effect of inhibitor concentrations (0.50-1.00 g/l), temperatures (30-60 C) and immersion time (4-12 h) was studied on the Inhibition Efficiency (IE) of the extract on Mild Steel (MS) immersed in a 0.5 M HCl solution. The constituents of the proposed inhibitor were identified by using a GC-MS. The media solutions and adsorbed film on MS were characterized using FTIR Spectrophotometer. SEM microgram and surface tester were applied for studying surface morphology and depth of attack profile. The optimum IE of 87.89% was obtained. The LCLE adsorption on MS followed Langmuir isotherm and pseudo-second-order adsorption kinetics. Activation energy (28.71 kJ/mol), entropy (-0.15 kJ/mol. K), average enthalpy (-28.00 kJ/mol) and Gibbs free energy (-11.43 kJ/mol) obtained at optimum condition indicate exothermic process and physical adsorption mechanism. The result obtained in this study compared well with many reported green inhibitors for MS corrosion.

No abstract

Proper slurry design is critical to the success of a cementing job. The best method to obtain a good slurry design with desired compressive strength is by laboratory experiments which involve experimenting different formulations and selecting the best composition for the specific cementing operation. This exercise is not only time consuming considering the amount of time required, but also expensive. Sixteen sets of experiments were conducted in the laboratory, and factorial design was used to design the experiments for the sensitivity analysis of four different factors impacting on the compressive strength of cement slurry. The responses from the 16 experimental runs were used to develop a model which can be used for optimization purposes. The model developed was simple, in agreement with the experimental data used and can be implemented using an ordinary simple calculator. Coefficients of main effects of X 1 , X 2 , X 3 , and

Modified Palm Kernel Shell Activated Carbon (PKSAC) using silver nanoparticle (Ag-NPs-PKSAC) was investigated on phenol uptake from aqueous solution. Effects of temperature (500–700 °C), time (90–120 min), and alkaline concentration (0.1–0.5 M) were studied on the yield and methylene blue numbers for the synthesis. Effects of initial concentration (100–200 mg/L), agitation (150–250 rpm), contact time (30–120 min), and adsorbent dosage (0.15–0.25 g) were studied in a batch experiment on percentage removal of phenol. The PKS, char, PKSAC and Ag-NPs-PKSAC were characterized using BET, FTIR, SEM, and proximate analyses. The synthesis of PKSAC was optimum at 608 °C, 0.5 M KOH, and carbonization holding time of 60 min. The optimum phenol uptake was 85.64, 90.29 and 91.70% for PKSAC, Ag-NPs-PKSAC, and commercial adsorbent, respectively. The adsorption mechanism of phenol followed the Langmuir isotherm and best described as physio-sorption with pseudo-second-order kinetics. Phenol exhibits high affinity (ΔS° = 0.0079 kJ/mol K) for Ag-NPs-PKSAC with favorable adsorption (ΔG° = -1.551 kJ/mol) at high temperature due to endothermic (ΔH° = 1.072 kJ/mol) nature of the system. The result obtained in this study compared favorably with the literature.