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Olive leaves were utilized to produce activated biomass for the removal of ciprofloxacin (CIP) from water. The raw biomass (ROLB) was activated with sodium hydroxide, phosphoric acid, and Dead Sea water to create co-precipitated adsorbent (COLB) with improved adsorption performance. The characteristics of the ROLB and COLB were examined using SEM images, BET surface area analyzer, and ATR-FTIR spectroscopy. COLB has a BET surface area of 7.763 m2/g, markedly higher than ROLB's 2.8 m2/g, indicating a substantial increase in adsorption sites. Through investigations on operational parameters, the optimal adsorption efficiency was achieved by COLB is 77.9% within 60 min, obtained at pH 6, and CIP concentration of 2 mg/mL. Isotherm studies indicated that both Langmuir and Freundlich models fit the adsorption data well for CIP onto ROLB and COLB, with R2 values exceeding 0.95, suggesting effective monolayer and heterogeneous surface adsorption. The Langmuir model revealed maximum adsorption capacities of 636 mg/g for ROLB and 1243 mg/g for COLB, highlighting COLB's superior adsorption capability attributed to its enhanced surface characteristics post-modification. Kinetic data fitting the pseudo-second-order model with R2 of 0.99 for ROLB and 1 for COLB, along with a higher calculated qe for COLB, suggest its modified surface provides more effective binding sites for CIP, enhancing adsorption capacity. Thermodynamic analysis revealed that the adsorption process is spontaneous (∆Go < 0), and exothermic (∆Ho < 0), and exhibits a decrease in randomness (∆So < 0) as the process progresses. The ΔH° value of 10.6 kJ/mol for ROLB signifies physisorption, whereas 35.97 kJ/mol for COLB implies that CIP adsorption on COLB occurs through a mixed physicochemical process. [ABSTRACT FROM AUTHOR]

Flue gas generated by power plants is considered one of the primary sources of CO2 emissions. Flue gas can be injected into depleted gas reservoirs to minimize the impact of CO2 and other pollutants such as sulfur dioxide (SO2) and nitrogen oxides (NOx). This work investigates the impact of gas impurities in flue gas on CO2 enhanced gas recovery in sandstone and carbonate reservoirs. Sorption analysis was conducted using flue gas with and without gas impurities on carbonate and sandstone rock samples at a temperature range between 50 and 100 °C and pressure up to 45 bar. The results showed that low clay content sandstone has the highest adsorption (17.3 mg/g) of purified flue gas (80%N2/20%CO2) compared to about 13 mg/g for clay-rich sandstone at a temperature of 50 °C and a pressure of 45 bar, which is believed to be a result of pore filling mechanism besides the van der Waals forces between the gas molecules and rock surface. Indiana limestone with low permeability revealed about 11 mg/g at similar conditions. The total gas uptake decreased by an average of 56% in sandstone rocks and 31% in limestone by injecting the flue gas that contained SO2 and NOx, which could be attributed to the higher affinity of these gas impurities to rock surface compared to CO2 and N2. The adsorption/desorption hysteresis in sandstone and carbonate rocks showed that the adsorption is physisorption in all cases. Increasing the temperature decreased the flue gas adsorption without any effect on its nature. [ABSTRACT FROM AUTHOR]

In this research study, waste fly ash (WFA) underwent acid activation and subsequent amine functionalization using ammonia solution. This treatment improves the porosity, thermal tendency and crystallinity of WFA. Modified WFA was tested under different experimental conditions to treat the wastewater consisting of different concentrations of cationic (methylene blue and rhodamine 6G) and anionic (methyl orange) dyes. As an individual, methylene blue (MB) and rhodamine 6G (Rh) showed ~ 100% and ~ 82% removal efficiencies respectively in an alkaline medium while methyl orange (MO) exhibited only ~ 20% adsorption in the same medium. An antagonistic effect was observed in adsorption when wastewater contains both cationic dyes whereas the combination of cationic and anionic dyes in solution manifested a synergistic effect. For all individual and binary dye combinations, there is a close agreement in observed and calculated uptakes when the data was fitted to the fractional order kinetic rate equation. The adsorption of all dyes is spontaneous and endothermic in nature except for MB/MO combination where the process is exothermic in nature. 24.93 mg/g, 24.83 mg/g, and 14.95 mg/g monolayer uptake capacities of MB, Rh, and MO were found respectively from isothermal analysis of single dye adsorption data. Further, extended sips model gave higher correlation coefficient (R2 = 0.99) and addressed the failed assumptions of both the Langmuir and Freundlich models. Overall, in the experimental results, the modified waste fly ash could act as successful adsorbent to treat dye bearing wastewater. [ABSTRACT FROM AUTHOR]

The industrial mine water produced by the Eshidiya phosphate mines posed discharge, safe storage, and reuse challenges. This study aimed to evaluate the hydrogeochemical characteristics of the mine water using physicochemical and biological analysis, the Piper model, the Durov model, and the saturation index model. Industrial mine water could be classified into three groups: the salinity type (SO42−–Cl−–HCO3–NO3−–Mg2+–K+), the carbonate flour apatite mineral (francolite) type (PO42−–Ca2+–Na+–F−), and the decompose organic type (DO, BOD, and COD). Two factors explained 73% of chemical variances: factor 1 (Mg2+, K+, HCO3−, SO42−, Cl−, and NO3−) and factor 2 (PO42−, Na+, Ca2+, and F−), which were regarded as indicative ions of the mineral–water interaction and the carbonate flour apatite mineral (francolite), respectively. The Na+–Cl−-type water (90%) was the dominant water type, which was followed by Ca+–Na+–HCO3 (10%). The Durov model diagrams displayed three hydrochemical facies: Na+–Ca2+–Cl− (80%), Na+–Cl− (10%), and Ca+–Mg2+–HCO3− (10%). Most of the mine water was saturated with major minerals, such as francolite, calcite, dolomite, aragonite, and fluorite, which might result from the water–rock interaction in phosphate beneficiation process. The unsaturation state of evaporite minerals, such as halite, gypsum, and anhydrite, indicated a low contribution of mineral–water interaction. [ABSTRACT FROM AUTHOR]

A new geopolymeric material has been fabricated from local Saudi Arabian resources using inorganic mineral polymerization technique. In this technique, the mineral polymer is synthesized from the following components: naturally occurring kaolin clay mineral, silica sand, sodium hydroxide, and water. Homogeneous samples of known amounts of clay minerals and silica sand were mixed with different ratios of clay and sand and sodium hydroxide solutions ranging from 13 to 19.7 mol/l. To accelerate the chemical polymerization reaction, the molded reactants were cured at 80 °C in an oven for 24 h to form stable and hard geopolymeric material. The synthesis parameters of mass of clay mineral, sand, NaOH and water were varied according to a statistical analysis design of experiment. The optimum amount of water is limited by the plastic limit of the clay, which is determined to be around 25%. Based on the results of the experimental design a geoploymer with a compressive strength of 27.1 MPa was achieved by sand to kaolin ratio of 1.5, water to kaolin ratio of 0.25 and NaOH to kaolin ratio of 0.17 under dry conditions and 18.1 MPa under wet conditions. [ABSTRACT FROM AUTHOR]

In this study, sewage sludge-derived activated carbon (SDAC) was synthesized, characterized, and tested for its potential as an adsorbent of methyl tert-butyl ether (MTBE). The SDAC was produced by activating the sludge with zinc chloride and subsequently subjected to various ranges of pyrolytic temperatures. It was then characterized using SEM/EDX, BET, and TGA. The SEM-EDX analyses showed that impurities like Fe, Al, Mg, Mn, Ca, and Na of the raw sludge were removed by the higher pyrolytic temperature and acid-washing procedures. TGA showed the thermal stability of the produced material. Results of the BET revealed a significant increase in surface area of the sludge from 1.5 m2/g to 385 m2/g after acid washing. The MTBE removal efficiency of 70% was achieved after 60 min with 2 g/L of SDAC at pH 6, and initial MTBE concentration of 1 ppm. The adsorption kinetics of SDAC fitted into pseudo-second-order reactions. This work demonstrated a beneficial use of a bio-waste material (sewage sludge) in water treatment technologies. [ABSTRACT FROM AUTHOR]

A mesoporous activated carbon is produced from oil fly ash (OFA) using chemical and thermal treatments at different activation conditions. The ash samples were refluxed with a range of compositions of sulfuric, nitric, and phosphoric acids followed by thermal activation in a tubular reactor. The composition of the acids and the reaction temperature were optimized to yield mesoporous activated carbon with a high surface area and yield. Several characterization methods were used to study the surface characteristics, morphology, functional groups, phase transition, and adsorption. FTIR spectra show the existence of carboxylic and amine functional groups, which increase with increasing percentage of nitric acid. SEM spot analysis and EDX demonstrate that the carbon content increases from 77.4 to 95.7 % upon chemical treatment. Specimens treated with a mixture comprises of 3.6 mol L HSO, 6.4 mol L HNO and 5.9 mol L HPO and activated at 990 °C have a BET surface area of 375.7 m g when compared to 4 m g for the original OFA. The BJH adsorption pore distribution indicates an average pore size of 50 Å with a total mesopore volume of 0.2211 cm g (73.6 % of the total pore volume). Thus, waste OFA is a suitable raw material for the production of activated carbon. [ABSTRACT FROM AUTHOR]

Combustion of heavy fuel oil at power generation facilities and desalination plants produce large quantities of heavy oil fly ash (OFA). Waste ash production is expected to increase with the increasing use of heavy or cracked oil as fuel in inefficient power generation facilities. Oil ash can pose a health hazard by affecting the respiratory system and may contaminate the water table if improperly dumped. Utilization of the heavy oil ash in construction materials provides a viable use for this by-product, thereby protecting the environment and eliminating the need for building special disposal areas for the ash. In this study, three different chemical treatment methods were used for the surface modification of oil fly ash. Elemental analysis indicated that the treatment process removes some of the elements such as vanadium, iron, and nickel from the OFA samples. FTIR analysis shows that the main difference between the three treatment methods is the introduction of three different functional groups. Untreated and surface-modified oil fly ash were blended with asphalt binder at a ratio of 2 % and used in asphalt concrete mixes. Performance grade of ash modified asphalt binders increased from 64-16 to 76-16. Asphalt concrete mixes modified with chemically treated OFA has 11 % higher split tensile strength, 25 % higher resilient modulus, 1,400 % increase in fatigue life and 55 % reduction in rutting as compared to neat asphalt concrete mix treated with the same asphalt content. Modifying asphalt binder with 2 % of chemically treated OFA significantly improves the performance of the asphalt pavement. [ABSTRACT FROM AUTHOR]

This study investigates the effect of two amine-based corrosion inhibitors in reducing the corrosion rate (CR) of 1018 carbon steel in formulated sea water. For discussion purposes, the two inhibitors are named Inhibitor A (belongs to the alkyl pyridine benzyl chloride quaternary family of inhibitors) and Inhibitor B (belongs to the alkyl amines family of inhibitors). The two inhibitors are routinely considered for applications by Saudi Aramco, the world's largest oil producing and processing company, for reducing its corrosion problems in carbon steel pipelines carrying oil and gas. The experimental apparatus was a circulating flow loop system inside an autoclave. The experimental work was performed at pH 8.2, 55 °C, and 1000 rpm. The inhibitors were evaluated at three different concentrations of 5, 10, and 15 ppm. The CR was determined using the weight loss method and electrochemical methods such potentiodynamic sweep and linear polarization resistance. The experimental results indicate that Inhibitor B reduced the CR more than that of Inhibitor A. [ABSTRACT FROM AUTHOR]

In this paper, oil fly ash (OFA), a by-product generated by the combustion of oil in power plants, was used as a filler for the preparation of low density polyethylene (LDPE) composite. Four different loadings of filler in the range 1-10%wt were used. Both mechanical and thermal properties were studied using tensile measurements and Differential Scanning Calorimetery. The effect of surface modification of OFA by functionalization with COOH group and the effect of polyethylene-grafted-maleic anhydride as a compatibilizer were also examined. Improvement in Young's modulus and yield strength of OFA was obtained in the range 1-2% as a result of chemical modification and mainly in the range 5-10%w due to compatiblization. However, a decrease in toughness and elongation at break was also observed. In general, functionalization and compatiblization improved small strain mechanical properties and failed to do the same for large strain properties of composites. No considerable effect for fly ash on melting point, on-set temperature and crystallization peaks was observed. Coupling of functionalization and compatiblization can enhance modulus and tensile strength mechanical properties of composites of LDPE and waste ash. [ABSTRACT FROM AUTHOR]

The objective of this study was to assess the extent and severity of metal contamination in urban soil around Queen Alia Airport, Jordan. Thirty-two soil samples were collected around steel manufacturing plants located in the Al-Jiza area, south Jordan, around the Queen Alia Airport. The samples were obtained at two depths, 0–10 and 10–20 cm, and were analyzed by atomic absorption spectrophotometry for lead (Pb), zinc (Zn), cadmium (Cd), iron (Fe), copper (Cu) and chromium (Cr) levels. The physicochemical factors believed to affect the mobility of metals in the soil of the study area were also examined, including pH, electrical conductivity, total organic matter, calcium carbonate (CaCO3) content and cation exchange capacity. The high concentrations of Pb, Zn and Cd in the soil samples were found to be related to anthropogenic sources, such as the steel manufacturing plants, agriculture and traffic emissions, with the highest concentrations of these metals close to the site of the steel plants; in contrast the concentration of Cr was low in the soil sampled close to the steel plants. The metals were concentrated in the surface soil, and concentrations decreased with increasing depth, reflecting the physical properties of the soil and its alkaline pH. The mineralogical composition of the topsoil, identified by X-ray diffraction, was predominantly quartz, calcite, dolomite and minor minerals, such as gypsum and clay minerals. Metal concentrations were compared using one-way analysis of variance (ANOVA) to compute the statistical significance of the mean. The results of the ANOVA showed significant differences between sites for Pb, Cd and Cu, but no significant differences for the remaining metals tested. Factor analysis revealed that polluted soil occurs predominantly at sites around the steel plants and that there is no significant variation in the characteristics of the unpolluted soil, which are uniform in the study area. [ABSTRACT FROM AUTHOR]

Natural bentonite was treated by hydrochloric, nitric, and phosphoric acids followed by washing with sodium hydroxide in order to enhance its adsorption capacity. The sample that treated with hydrochloric acid followed by further treatment with NaOH showed the highest cation exchange capacity with a value of 51.20 meq/100 g. The zero-point of charge for this sample was found to be 4.50. Adsorption isotherms for both cobalt and zinc were fitted using Langmuir, Freundlich, and Redlich-Peterson and showed an adsorption capacity of 138.1 mg Co2+ and 202.6 mg Zn2+ per gram of treated sample. [ABSTRACT FROM AUTHOR]

A simple and rapid HPLC method for the determination of simvastatin using a C18-Hypersil column and acetonitril-phosphate buffer-methanol (5: 3: 1, v/v/v) as a mobile phase with detection at 230 nm was proposed. Commercial pharmaceutical tablets were analyzed with a linear range for simvastatin up to 1.884 mg % and a regression coefficient of 0.9995. The method is found to be precise, accurate, reliable, and selective. [ABSTRACT FROM AUTHOR]