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Surfactant flooding is adjudged one of the most promising chemicals enhanced oil recovery (cEOR) methods due to its high microscopic sweep efficiency. This surfactant shows high potential in mobilizing trapped residual oil (ganglia) through excellent lowering of the interfacial tension (IFT) between the crude oil-aqueous interface to ultra-low values while favorably altering the wettability (oil-wet to water-wet). Surfactant adsorption is a critical factor that determines how successful this cEOR method will be as well as the project economics. Surfactant retention due to adsorption caused majorly by electrostatic forces of attraction between hydrophilic head, and the positive and negative charges of the adsorbent solid surface leading to insufficiency of the remaining surfactant concentration in the injected slug to achieve the supposed ultralow IFT needed for mobilization. This article describes the experimental data on the adsorption of a natural surfactant derived from linseed oil and the results from its adsorption isotherm modelling. This anionic surfactant (LSO-derived) has a CMC value of 2500 ppm, average fractional removal of 0.60 under a range of concentrations (500, 1000, 2000, 4000, 8000, and 12000 ppm), with the adsorption kinetics revealing that adsorption density rises as a function of time with increasing adsorbate concentrations. Five different classical adsorption isotherm models were explored- in the form three (Redlich-Peterson or R-P ), two (Langmuir, Freundlich, Temkin), one (Linear-Henry) parameters models. Their characteristics adsorption parameters were calculated, with highest adsorption capacity value of 2.955mg/g obtained from the simulation using OriginPro 2021 Software. The analysis demonstrates that the R-P model provided the greatest fit as a hybrid model with the highest correlation coefficient value. The kinetic adsorption models Pseudo-First Order (PFO), Pseudo-Second Order (PSO), Pseudo-Nth Order (PNO), and Intra-Particle Diffusion (IPD), as well as their thermodynamic property model, were also examined in addition to static isotherm models. On average, using non-linear regression approach, PSO and PNO provided the best appropriate fit models under this hypothesis, with correlation values of the nth order ranging from 0.443 to 2.122 (excluding 5.847 the non-converged fit value). Prior to thermodynamic analysis, it was confirmed by the IPD with multi-linear graphical characteristics that intra-particle transport was not the only rate-limiting step in adsorption processes and proceeded spontaneously by the This model can be utilized to design a template for LSO surfactant-rock adsorption in chemical flooding schemes for EOR applications., (© 2023 The Author(s).)

This study was piloted to evaluate bioaccessibility of particulate-bound trace elements using synthetic epithelia lung fluid; in which dipalmitoylphophatidylcholine was substituted with locus bean gum (LBSFL). The resulting data reveal that no significant change in physicochemical characteristics of the stimulated lung fluid compare with similar synthetic fluids; pH value of 7.3, density (0.998gcm -3 ), conductivity (13.9 mS m -1 ), surface viscosity (1.136 × 10 -12 pas) and surface tension (50.6 mN m -1 ). To prove the potential applicability of the fluid in in vitro bioaccessibility test, we compared bioaccessibility of particulates-bound trace elements using this fluid with those of stimulated epithelial lung fluid. Bioaccessibility were relatively low values (<30%) in locus bean substituted lung fluid and stimulated epithelial lung fluid. Specifically, As and Cd had significantly higher bioaccessibility values in locus bean substituted lung fluid than stimulated epithelial lung fluid. The data demonstrate that fluid formulated and used in this study can provide a suitable means of evaluate bioaccessibility of trace elements-bound to airborne particulates. •The fluid was used for assessing bioaccessibility of particulate matters-bound trace elements•The formulated fluid can be applied to study in toxicity assessment•The data can be used for inter-laboratory comparison of bioaccessibility of particulate -bound trace element and could stimulate environmental concerns on the impacts of airborne particulates., (© 2019 The Authors.)

This dataset focuses on the causes and effects of sick building syndrome among users of selected facilities in Lagos. A mixed research approach of field measurement and cross-sectional survey was adopted. Descriptive statistics were implemented on the data acquired and are reported on tables and figures. The significance of this data leverages on providing insight and consciousness of sick building syndrome to users and occupants of constructed facilities. The survey dataset when analyzed can show direction on physical quantities levels that can be experienced in public buildings in tropical region.

This research investigated the production of biodiesel from soybean oil (transesterification process) using pure calcium oxide and calcium oxide obtained from eggshell as heterogeneous catalysts. Uncalcined eggshell and calcined eggshell catalysts produced were analysed using XRF and XRD spectrometers. The processing parameters considered during the transesterification of the soybean were methanol/oil mole ratio, catalyst concentration and reaction time and their effects on biodiesel yield were evaluated. Reaction temperature of 60 °C and stirring rate of 450 rpm (revolution per minute) were kept constant. As a result of calcination, XRF analysis revealed an increase in CaO percentage composition of eggshell catalyst from 96% to 97%. Also, the biodiesel yields obtained revealed similar performance patterns for both the calcined eggshell catalyst and the pure CaO catalyst.