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Erionite was synthesized under hydrothermal and static conditions and was characterized by Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM) and BET surface area measurement. The dynamic adsorption experiments were carried out on Temperature programed desorption (TPD) plus Chemisorption system (Micrometrics ASAP 2920 unit). Adsorption was found to be high initially and it then decreases with increase in injected volume. In batch reactor it was found that adsorption increases with increase in contact time between 2-chloroethyl ethyl sulfide and erionite only up to around 12 h after which it remains almost constant. It is exhibited from the data that maximum adsorption capacity of erionite for 2-chloroethyl ethyl sulfide was 70.26 mg/g at 25 °C. Pseudo second order kinetics was found to describe adsorption process better than pseudo first order kinetics. Freundlich and Langmuir isotherms applied on the adsorption data reveal that data fitted best for Freundlich model. Desorption pattern was analyzed which shows two types of peaks, sharp peak representing desorption of physisorbed 2-chloroethyl ethyl sulfide and a broad representing desorption of strongly chemisorbed 2-chloroethyl ethyl sulfide. Further it was observed that the adsorbent can be recycled and reused again. [ABSTRACT FROM AUTHOR]

Oil palm mesocarp fibre (OPMF) was pyrolysed on zeolite synthesised from oil palm ash (OPAZ) by using a slow heating fixed-bed reactor at 400 °C–600 °C. The maximum bio-oil yield of OPAZ-catalysed pyrolysis at 550 °C was 37.98 wt%, which was higher than that of non-catalytic pyrolysis (31.95 wt%) at the same temperature. GC–MS revealed the extensive variety of oxygenated organic compounds in the bio-oils derived from the non-catalytic and catalytic pyrolysis. Catalytic pyrolysis increased the amount of light phenol relative to that of heavy phenols and remarkably reduced the amount of acids, alcohols, hydrocarbons and hydrocyclic compounds. The oxygen content of the bio-oil decreased, resulting in enhanced fuel potential of the bio-oil and other valuable chemicals. The morphology and textural characteristics of OPAZ sustained the propensity of the catalyst-driven pyrolysis by upgrading the OPMF pyrolysis oil into a fuel-grade bio-oil. [ABSTRACT FROM AUTHOR]

Abstract: Zeolite-A was synthesized and converted into various ion-exchanged catalytic forms successfully. These catalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer Emmett Teller (BET) surface area measurement and thermal programmed desorption (TPD). Their catalytic activity was tested on the synthesis of benzimidazole using o-phenylenediamine (OPDA) and aldehyde at room temperature. The reaction proceeds efficiently under ambient conditions. The catalysts gave a high isolated yield of benzimidazole in a shorter reaction time at room temperature and were recycled several times. [Copyright &y& Elsevier]

Highlights: [•] Synthesis of Zeolite-A, MCM-22, Zeolite-X and Erionite by hydrothermal method. [•] Zeolites were characterized by using XRD, FTIR, BET, NH3-TPD, SEM and EDS techniques. [•] Dynamic adsorption of DMMP on zeolites was carried out using TPD plus chemisorption system. [•] Thermal desorption of DMMP on zeolites was carried using the same system. [ABSTRACT FROM AUTHOR]

This study aimed to optimize the synthesis of valuable glycerol carbonate (GC) over calcined oil pam fuel ash derived catalyst. A surface response methodology optimization study was conducted using the Box-Behnken optimization tool to minimize the reaction parameters and optimize GC yield and glycerol conversion. Also, the effect of intraparticle and external mass transfer resistance was conducted and the intrinsic kinetic model of the transesterification reaction was established. Overall, the transesterification temperature had significant effects on the variables of GC yield and glycerol conversion, while the catalyst loading and reaction time trivially affected the response parameters. Under optimized parameters of 80 °C reaction temperature, dimethyl carbonate (DMC)/glycerol molar ratio of 5, 5 wt% catalyst loading and 112 min reaction time, GC reached 95% with a desirability of 1. Theoretical elucidation indicates that transesterification reaction over the catalyst was unaffected by external mass transfer resistance and intraparticle diffusion above 125 μ m particle size. The catalyst is heterogeneous and can be reused for five times while sustaining about 81.3% of GC yield. Image 1 • Calcined oil palm fuel ash catalyst was used to synthesize glycerol carbonate, GC. • The reaction conditions were optimized using response surface methodology. • Optimized reaction conditions attained 97% glycerol conversion and 95% GC yield. • The catalyst sustained five cycles of reusability with slight deactivation. [ABSTRACT FROM AUTHOR]

Antibiotics are an emerging water pollutant without universally agreed regulations. Hence, its removal from the water will minimize antibiotics resistance bacteria. Herein, facile pyrolysis at 500 °C for 3 h was deployed to convert d -glucose to sheet-like graphitized carbon (GLU-500) for the removal of tetracycline antibiotics. The carbon material was characterized and the effect of pH, contact time, and initial concentration of tetracycline was elucidated. Results revealed that pyrolysis temperature tailored the morphology, functional group, and textural characteristics to accumulate a high amount of tetracycline. Electrostatic attraction at a pH of 5 favored the highest removal of 138.32 mg g−1of tetracycline at 30 °C, however, this adsorption capacity declined at increasing pH due to the formation of zwitterions that imposes a diffusion barrier. A multilayer adsorption was observed for the tetracycline-GLU-500 system, which was best described by Freundlich isotherm with R2 of 0.94 − 0.99. Also, the pseudo-second-order kinetic model confirms that thetetracycline-GLU-500 system adsorption is mainly by chemical interaction. The study confirms that abundant glucose can be a sustainable precursor for treatment of antibiotics contaminated water. [Display omitted] • d -glucose was used to produce sheet-like graphitized porous carbon via pyrolysis. • The porous carbon facilitated the removal of tetracycline antibiotics from water. • Maximum adsorption capacity reached 286.63 mg g−1 at pH of 5 and 30 °C. • Langmuir isotherm best describes the Glucose-tetracycline adsorption system. [ABSTRACT FROM AUTHOR]

Nanocomposites of titanium dioxide (TiO 2) and multi-wall carbon nanotubes (MWCNTs) were successfully synthesized (TiO 2 -MWCNTs) from MWCNTs and titanium tetrachloride (TiCl 4) as starting precursors using ultrasonic-assisted technique. The impact of the different weight percentages of MWCNTs (1, 3, 5, and 7 wt%) on TiO 2 optical, structural, and morphological properties were investigated. Subsequently, the photocatalytic activity was assessed by organic dyes degradation such as methylene Blue (MB) and rhodamine B (RhB) under ultraviolet (UV) light exposure. The characterization of synthesized materials demonstrated the anatase phase formation in both pure TiO 2 and the TiO 2 -MWCNTs nanocomposite, according to X-ray diffraction analysis. The morphology analysis of TiO 2 -MWCNTs nanocomposites using FESEM and TEM confirmed the uniform dispersion of MWCNTs with an exterior diameter of 12–16 nm within the TiO 2 matrix. The BET measurement of the sample's specific surface areas identified that the MWCNTs addition resulted in the increase of surface area from 76.34 to 194.35 m2 g−1 for pure TiO 2 and TiO 2 /7 wt% MWCNTs, respectively. Furthermore, TiO 2 /7 wt% MWCNTs nanocomposite had lower optical bandgap energy and higher photocatalytic performance as compared to the pure TiO 2. The photodegradation efficiency of TiO 2 /7 wt% MWCNTs nanocomposite increased from 63.63 % to 92.36 % for MB and 71.56 % to 94.13 % for RhB compared to pure TiO 2 , after 60 min UV light exposure. [Display omitted] • TiO 2 -MWCNT nanocomposite was synthesized using the ultrasonic method. • Photodegradation of cationic and anionic organic dyes using TiO 2 -MCWNT was studied. • TiO 2 -MWCNT showed maximum removal for RhB followed by MB dyes. • The addition of MWCNT can enhance organic dyes degradation efficiency. [ABSTRACT FROM AUTHOR]

The rapidly expanding global energy demand is forcing a release of regulated pollutants into water that is threatening human health. Among various wastewater remediating processes, electrocoagulation (EC) has scored a monumental success over conventional processes because it combines coagulation, sedimentation, floatation and electrochemical oxidation processes that can effectively decimate numerous stubborn pollutants. The EC processes have gained some attention through various academic and industrial publications, however critical evaluation of EC processes, choices of EC processes for various pollutants, process parameters, mechanisms, commercial EC technologies and performance enhancement via other degradation processes (DPs) integration have not been comprehensively covered to date. Therefore, the major objective of this paper is to provide a comprehensive review of 20 years of literature covering EC fundamentals, key process factors for a reactor design, process implementation, current challenges and performance enhancement by coupling EC with pivotal pollutant DPs including, electro/photo-Fenton (E/P–F), photocatalysis, sono-chemical treatment, ozonation, indirect electrochemical/advanced oxidation (AO), and biosorption that have substantially reduced metals, pathogens, toxic compound BOD, COD, colors in wastewater. The results suggest that the optimum treatment time, current density, pulse frequency, shaking speed and spaced electrode improve the pollutants removal efficiency. An elegant process design can prevent electrode passivation which is a critical limitation of EC technology. EC coupling (up or downstream) with other DPs has resulted in the removal of organic pollutants and heavy metals with a 20% improved efficiency by EC-EF, removal of 85.5% suspended solid, 76.2% turbidity, 88.9% BOD, 79.7% COD and 93% color by EC-electroflotation, 100% decolorization by EC-electrochemical-AO, reduction of 78% COD, 81% BOD, 97% color by EC-ozonation and removal of 94% ammonia, 94% BOD, 95% turbidity, >98% phosphorus by aerated EC and peroxicoagulation. The major wastewater purification achievements, future potential and challenges are described to model the future EC integrated systems. [ABSTRACT FROM AUTHOR]

Banana trunk waste was utilized to produce activated carbons with improved surface area and phosphorous atom dispersed surface through the chemical activation method using phosphoric acid. Banana trunk activated carbon (BTAC) production was optimized through the rotatable central composite design (RCCD) approach of the response surface methodology (RSM). The independent variables selected for optimization were activation time (35.5–134.5 min), activation temperature (367–932 °C), and H 3 PO 4 concentrations (0.36–8.14 mol/L). The optimized conditions of the independent variables obtained through RCCD were 50 min (activation time), 583 °C (activation temperature), and 6.60 mol/L (H 3 PO 4 concentration) for a maximum Brunauer-Emmett-Teller (BET) surface area of 1290 m2/g. Banana trunk activated carbon samples were characterized for bulk and surface elemental composition, surface morphology, thermal stability, functional groups, pHzpc, and crystallinity behavior. The characterization results suggested that BTAC has a porous surface with carbon as the backbone element with the highest percentage of 78%. The oxygen atom occupies the surface with 12%, and the phosphorus atom is spread almost 6% over the carbon surface. The raw banana trunk was thermally decomposed at an onset temperature of 240 °C and above, whereas the banana trunk (BTAC) was thermally stable up to 700 °C. Phosphoric acid-activated banana trunk activated carbon composed of the following surface functional groups: –OH, –C = O, -P = O, -P-O-C, and multiple carbon-carbon bonds. [Display omitted] ∙ Banana trunk waste was utilized to produce phosphorous dispersed activated carbon ∙Optimization was performed for the maximum BET surface area ∙Optimum dosage of H 3 PO 4 activation significantly increased the BET surface area. ∙Banana trunk AC surface consists of phosphorous as -P O-, and -P-O-C- groups ∙Banana trunk AC are thermally stable and semi-crystalline in nature [ABSTRACT FROM AUTHOR]

[Display omitted] • Aniline as a toxic aromatic uptake from industrial effluents was reviewed. • The different empirical findings on the equilibrium isotherms, kinetics and thermodynamics. • Molecular modelling and simulation of aniline adsorption. • Azo-linked porous organic polymer is the best adsorbents for the removal of aniline. • The best fit kinetic model for aniline adsorption is the pseudo-second-order model. This review aims to report the efficiency of the adsorption of industrial pollutants, aniline, from wastewater. It was observed from the review that an Azo-linked porous organic polymer (AZO-POP-1) is the best adsorbents for the removal of aniline from aqueous media, with a capacity adsorption (q max) of 1059 mg/g. In terms of factors that affect the efficiency of adsorbents, temperature seems to be the most influential. Aniline uptake best-fit both the Langmuir and Freundlich isotherm models as well as a pseudo second order kinetic model. Different potential adsorbents have been examined through simulations, usually using density functional theory (DFT) or ab-initio method. Most of the time they are simulated in the gas phase, but for a realistic adsorption model, they should be simulated in the solvent phase. Although some studies have been reported on molecular modeling of aniline adsorption using a different range of computational approaches, there are still a lot of issues to be addressed. These issues include the solvent effects which are not properly modeled, the calculation of adsorption energy which is not taking the environment into account, and possibly the temperature effects. [ABSTRACT FROM AUTHOR]