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Air-conditioning systems make the most significant part of energy consumption in the residential sector. There is no denying that it is essential to produce a comfortable indoor thermal environment for residents in a building. The actual goal is to achieve thermal comfort level without putting too much cost on the ecological system by trying to conserve the amount of energy consumed. An effective way to help achieve such a goal is by incorporating thermal insulation in buildings. Thermal insulations help reduce thermal energy gained during the implementation of a desired thermal comfort level. This study aims to use an environmentally friendly nanoparticle of date pits to create thermal insulations that can be used in buildings. Different ratios of the nanoparticle of the date pits and sand composite were investigated. Fourier transform infrared spectroscopy and scanning electron microscopy were used to characterize the new materials. The material with nanoparticles of date pits and 50% by-volume epoxy provided good thermal insulation with thermal conductivity of 0.26 W⁄mK that could be used in the existing buildings. This has the potential to reduce the overall energy consumption by 4,494 kWh and thereby reduce CO2 emissions of a 570 m2 house by 1.8 tons annually. In conclusion, the future of using nanoparticles of date pits in construction is bright and promising due to their promising results. [ABSTRACT FROM AUTHOR]

Incineration has emerged as one of the acceptable ways to treat municipal solid waste (MSW) due to its potential in reducing the mass and volume of the waste. However, it produces two major by-product residues, namely MSW-bottom ash (MSW-BA) and MSW-fly ash (MSW-FA). These residues have gained great attention to their hazardous nature and potential to be reused and recycled. In this paper, the physicochemical characterizations of the MSW-BA and the MSW-FA were performed, followed by a systematic investigation of metals extraction from MSW-BA and MSW-FA. Various extracting agents were used to investigate the possibility to extract 21 metals including cadmium (Cd), vanadium (V), chromium (Cr), and lead (Pb). It was revealed that some metals were present in a high amount in the MSW-BA while other metals were higher in the MSW-FA. Moreover, the energy-dispersive X-ray spectroscopy results revealed that the MSW-BA was dominated by oxygen (O) 55.4 ±0.6 wt%, silicon (Si) 22.5 ±0.3 wt%, and calcium (Ca) 18.5 ±0.2 wt%. On the other hand, the MSW-FA was enriched with Ca 45.2 ±0.5 wt%, and O 40.3 ±0.4 wt%. From the scanning electron microscopy, the MSW-BA was observed as flaky with an irregular surface that consisted of large pores, while, the MSW-FA was present as agglomerated particles and had a bimodal distribution. Moreover, Fourier transform infrared spectroscopy revealed that Al-Fe-OH, Al-Al-OH, Si-O, C-O, and C-H were some of the major functional groups present in the ashes. The F-tests concluded that the metal extraction from the MSW-BA and MSW-FA were significantly affected by the acid type. it is concluded that nitric acid and phosphoric acid were the best-suited acid for the MSW-BA while sulfuric acid and phosphoric acid for the MSW-FA. More than 11 wt% of Cd and 9 wt% of Cu were extracted from MSW-BA while 6 wt% of Pb and 4.5 wt% of V were extracted from the MSW-FA. The present methodology is an interesting development in metal extraction from the MSW-BA and the MSW-FA, which can develop in a cost-effective and sustainable option to utilize MSW. [ABSTRACT FROM AUTHOR]

This study investigated the use of eggshell membrane (ESM) as a bio-sorbent and the effect of temperature, pH, and initial concentration on its efficiency. Furthermore, by altering the chemical composition, modified eggshell membrane (MESM) was prepared, and its efficiency was compared with the ESM. Results showed that the adsorption of boron preferred an acidic condition; pH 6 at 35 °C. In addition, the positive value of ΔH° suggested that the reaction favored endothermic pathway, while the negative value for ΔG° further suggested that the adsorption process was spontaneous. Furthermore, the ESM could adsorb 97% of boron, while MESM was able to adsorb 95%. From the Fourier transform infrared (FTIR), different functional groups were recorded on the surface of the ESM and MESM, and they played key role in the boron adsorption mechanisms. Linear Freundlich model was suggested to best describe the experimental data with 99.4% correlation coefficient. [ABSTRACT FROM AUTHOR]

Bromide ions (Br − ) are associated with toxic by-products that might be produced during the disinfection of drinking water. The removal of Br − from water using roasted date pits (RODPs) and activated carbon was investigated. The percentage removal capacity of Br − was studied under various experimental conditions including solution pH, adsorbent mass and particle size, and initial Br − concentration. Surface characterisation was investigated using scanning electron microscopy (SEM) and Fourier transform infrared (FTIR). SEMs images showed the presence of fine particles (debris) on the surface of the adsorbent solids. The raw date pits (RDPs) surface images showed a marked difference in pore sizes upon roasting, whilst FTIR spectra showed a slight shifting in –O–H, C O, and –C–O stretching in addition to –O–H bending for the RODPs. In addition to the Freundlich and Langmuir isotherm models, the experimental data were fitted to different adsorption kinetic models. It was found that the adsorption of Br − onto RODPs followed pseudo-second order mechanism. Removal rates of around 54% were obtained at lower pH. [ABSTRACT FROM AUTHOR]

Abstract: The treatment of wastes has become one of the most important concerns of modern society to protect the environment. Application of microemulsion modified raw local diatomite (μE-MD) and activated carbon (μE-MAC) as solid extractants for removing inorganic (iron, copper and lead ions) and organic pollutants (soot, oxidations, nitration and sulphation products) from waste lubricants (WL) at a moderate heat have been presented. The results summarised herein are also part of an investigation conducted to evaluate the adsorption removal by taking into consideration the experimental parameters such as initial pollutant concentration and temperature. The raw and modified adsorbents were effective towards all pollutants especially for the inorganic pollutants with high removal percentages (Fe: 34–68%, Cu: ∼65%, Pb: 55–80%) and (oxidation: 7–15%, nitration: 41–46%, sulphation: 5–29%, soot: 42–61%) which indicated the suitability of these new materials for extraction of organic and inorganic pollutants from non-aqueous WL medium. The removal percentages, however, varied from adsorbent to another“. The pHzpc (pH at point of zero charge) was carefully estimated for all adsorbents (raw diatomite (RD), μE-MD, activated carbon (AC), μE-MAC) and found to be (8.6, 7.8, 7.3, 9.1), respectively. The experimental results were also plotted and treated with Langmuir isotherm, uncommon isotherm shapes were obtained. Therefore, it was not fitted to the experimental results which might reflect a complex nature of adsorbing onto the adsorbents. However, this behaviour gave an indication on the complex adsorption mechanisms. Finally, the mode of interaction between the pollutants and the μE-MD and μE-MAC was characterised by comparing the changes in the position and intensity of the surface functional groups using the FTIR technique. Three mechanisms of the adsorption of organic (oxidation, nitration and sulphation) and inorganic (heavy metals) pollutants were possible: (i) adsorption by an electrostatic force of the anionic head group of the surfactant and the positive charge of the organic molecules or the cation metal, (ii) adsorption by tail groups of the surfactant and the hydrophobic character of the organic molecules. The cation heavy metals and the organic compounds have basic characteristics and therefore were expected to interact strongly with the anionic head groups of the surfactants (RCOO−). In the contrary, the cationic heavy metals were not expected to interact by the tail groups of the surfactant where the ionic radii of these ions may explain the differences between every metals removal percentage and (iii) filling the channel (pores) of the RD and the AC by dissolving in the microemulsion micelles. [Copyright &y& Elsevier]

Abstract: The viscosity index (VI) and the base number (BN) of motor oils are the most important parameters to be measured in order to assess their performance and service time. Both parameters were simply obtained for virgin and recycled motor oil samples using multivariate calibration based on the FTIR data. Analysis showed that the PLS-1 has outperformed CLS and PCR for the oil parameters prediction. Five and four PLS-1 latent variables were found optimum to obtained the VI and the BN from the FTIR data; respectively. With high accuracy (99–102%) and precision (3–11%), the BN could be determined over the range 4.57–16.45mgKOHg−1 and the VI over the range 96–153. The outputs of the PLS-1 were found comparable to those obtained by the expensive and time-consuming ASTM methods. This developed method is highly recommended for quick monitoring of the motor oil quality parameters. [Copyright &y& Elsevier]

Abstract: The precise determination of the heat of combustion is of great importance for trading automotive diesel. The net heat of combustion (NHC) of fuel is related to the hydrogen elemental composition of fuel as obtained by elemental analysis. Heat of combustion expressed as gross heat of combustion (GHC) and net heat of combustion (NHC) have been predicted from data obtained by proximate analysis (density, ash, water and sulphur content) (ASTM D4868). GHC was obtained using bomb calorimetry (ASTM D240). The results of ASTM D4868 and ASTM D240 were found in good agreement. GHC and NHC fall within the relatively narrow range 45.24–46.08 and 41.91–43.27MJ/kg, respectively. GHCs of tested diesel samples are, on average, about 7% greater than NHCs. The present paper also present a simple analytical method for determination of hydrogen content, GHC, and NHC of automotive diesel fuel using FTIR spectroscopy and partial-least squares calibration (PLS-1). PLS-1 had a high prediction power for prediction of hydrogen from FTIR spectra of diesel samples. The spectral ranges used in calibration were 400–670 and 2846–2970cm−1. On the other hand, classical least squares calibration (CLS) was found invalid for determination of hydrogen content in diesel. The results obtained by the proposed analytical method were almost to those obtained by ASTM D4868 and ASTM D240. PLS-1 method, offers a simple and reliable analytical method for quantification of hydrogen content in diesel samples without running expensive analysis like those carried out using carbon, hydrogen, and nitrogen (CHN) instruments. [Copyright &y& Elsevier]

Abstract: As a result of the changes that occur during their use, used engine oils tend to differ in chemical and physical composition from a virgin oil. In general recycled oils have: much higher water and sediment levels than virgin oil; relatively higher concentrations of organic compounds (oxidation products); and relatively higher levels of metals such as Fe, Cd, Cr, Pb, etc. Therefore, the aim of this work was to investigate, assess and to observe, by means of the physical and the chemical properties of the oils, atomic absorption (AA), inductive couple plasma (ICP) and Fourier transform infrared (FTIR) analyses the extent of the differences occurring between the virgin and recycled oil. In important part of this work was also the development of analytical techniques based on the use of FTIR spectroscopy; in relation to the rapid analysis of lubricants; in particular for the differentiation of virgin and recycled oil. The results obtained were expected to be useful for differentiation purposes, providing information on whether the metal concentrations and oxidation products could be an appropriate feature for differentiating a particular oil sample from the others. This work is categorized into a two-step procedure. Firstly, an evaluation of a typical FTIR spectrum of an engine oil sample (mono- and multigrade) is presented. The broad feature centered at 1716cm−1 is due to the presence of carbonyl containing degradation products of oil. A band observed at 1732, 1169, 1154 and 1270cm−1 assigned to the polymethacrylate stretching vibrations, allows the determination of viscosity modifier and pour point depressant additives. The observed differences in the specific spectral bands (1732, 1169, 1154 and 1270 and 1716cm−1) are investigated and discussed. Secondly, an analytical technique for the measurement of the levels of the wear metals is also applied. [Copyright &y& Elsevier]

Abstract: In this paper, an attempt has been made to develop a feasible procedure for the prediction of quality parameters of motor gasoline and to discriminate between the different adulterated motor gasoline samples using density values, distillation temperatures and Fourier transform infrared (FTIR) analyses along with multivariate calibrations without the need for using chromatographic separation or other expensive instruments such as an octane number analyser. Ten blend mixtures of regular and super motor gasoline were prepared in order to study density, distillation temperatures and FTIR spectra characteristics for each blend. Distillation temperatures for the pure and blend mixtures of regular and super motor gasoline at initial boiling point (IBP) to final boling point (FBP) at 5%Vol. interval were obtained. Accurate and complete distillation data on the uncontaminated fuel would be essential for comparison. Thirteen peaks of the absorbance at the wavenumbers: 434, 461, 484, 673, 694, 1030, 1086, 1217, 1231, 1460, 1497, 1606 and 3028cm−1 were chosen to perform the multivariate calibration. The results obtained were expected to be useful in determination and differentiation purposes, providing information on whether the density values, distillation temperatures and FTIR analyses along with multivariate method could be an appropriate feature for differentiating a particular pure motor gasoline sample from the others. The observed differences in the specific spectral bands are investigated and discussed. They have proven to be an effective combination in the pursuit of management''s differentiation goals. [Copyright &y& Elsevier]