Olumide Bolarinwa Ayodele

Ackee apple (Blighia sapida) seeds: a novel adsorbent for the removal of Congo Red dye from aqueous solutions

The ability of ackee apple (AA) seeds to remove Congo Red (CR) dye from aqueous solution was investigated. AA was characterised using thermo gravimetric analyser, scanning electron microscopy, Braunauer Emmett Teller, pHpzc, elemental analysis and Boehm titration. The effects of operational parameters such as adsorbent dosage, contact time, initial dye concentration and solution pH were studied in a batch system. pH has a profound influence on the adsorption process. Maximum dye adsorption was observed at pH 3.0. The reaction was fast, reaching equilibrium in 90 min. Adsorption data were best described by Langmuir isotherm and the pseudo-second-order kinetic model with a maximum monolayer coverage of 161.89 mg·g−1. Both boundary layer and intraparticle diffusion mechanisms were found to govern the adsorption process. Thermodynamic parameters such as standard free energy change (Δ G 0), standard enthalpy change (Δ H 0), and standard entropy change (Δ S 0) were studied. Values of Δ G 0 varied between−30.94 and−36.56 kJ·mol−1, Δ H 0 was 25.61 kJ·mol−1, and Δ S 0 was 74.84 kJ·mol−1·K−1, indicating that the removal of CR from aqueous solution by AA was spontaneous and endothermic in nature. Regeneration and reusability studies were carried out using different eluents. AA gave the highest adsorption efficiency up to four cycles when treated with 0.3 M HCl. AA was found to be an effective adsorbent for the removal of CR dye from aqueous solution.

The influence of catalyst factors for sustainable production of hydrocarbons via Fischer-Tropsch synthesis

Abstract Fischer-Tropsch synthesis (FTS) is a process which catalytically converts syngas (H2 and CO) into clean hydrocarbon fuels. Syngas can be derived from non-petroleum feed stocks such as coal, natural gas or biomass. Increasing the quality of products by development of novel catalysts with high activity and selectivity is desirable in FTS reaction. This article reviews and summarizes recent developments in FTS catalysts and the effects of key factors such as active metals, catalyst supports and promoters on feedstock conversion and product selectivities.

Polymer’s Characterization and Properties

This chapter discussed the characterization and properties of polymeric materials. Prominent characterization techniques used for analyzing polymeric materials are mass spectrometry (MS), nuclear magnetic resonance (NMR), and gel permeation chromatography (GPC), which are used for measuring mass-to-charge ratio (m/z) of analyte ions. Other methods used for this purpose include matrix-assisted laser desorption/ionization (MALDI), electrospray ionization (ESI), and secondary-ion mass spectrometry (SIMS). X-ray diffraction (XRD) is used for solid-state analysis such as degree of crystallinity and crystal structure as well as the unit cell parameters, while Fourier transform infrared spectroscopy (FTIR) is used for identification of the polymer functional groups. NMR helps to identify and characterize various polymers and also provides information on the mobility of their molecules, while X-ray photoelectron spectroscopy (XPS) provides information regarding the chemical composition of polymeric materials. The physical properties such as hydrophobicity, functional groups, and flexibility of the polymer chain structure and chemical properties such as chemical reactivity, toxicity, biocompatibility, chirality, adsorption capacities, chelation, and polyfunctionality of polymeric materials are also discussed.

Influence of oxalate ligand functionalization on Co/ZSM-5 activity in Fischer Tropsch synthesis and hydrodeoxygenation of oleic acid into hydrocarbon fuels

Achieving high degree of active metal dispersions at the highest possible metal loading and high reducibility of the metal remains a challenge in Fischer Tropsch synthesis (FTS) ufeffas well as in hydrogeoxygenation (HDO)ufeff.ufeffThis study therefore reports the influence of oxalic acid (OxA) functionalization on theufeff metal dispersion, reducibility andufeff activity of Co supported ZSM-5 catalyst in FTS and HDO of oleic acid into paraffin biofuel. The Brunauer–Emmett–Teller (BET) results showed that cobalt oxalate supported ZSM-5 catalyst (CoOx/ZSM-5) synthesized from the incorporation of freshly prepared cobalt oxalate complex into ZSM-5 displayed increase in surface area, pore volume and average pore size while the nonfunctionalized cobalt supported on ZSM-5 (Co/ZSM-5) catalyst showed reduction in those properties. Furthermore, both XRD and XPS confirmed the presence of Co° formed from the decomposition of CoOx during calcination of CoOx/ZSM-5 under inert atmosphere. The HRTEM showed that Co species average particle sizes were smaller in CoOx/ZSM-5 than in Co/ZSM-5, and in addition, CoOx/ZSM-5 shows a clear higher degree of active metal dispersion. The FTS result showed that at CO conversion over Co/ZSM-5 and CoOx/ZSM-5 catalysts were 74.28% and 94.23% and their selectivity to C5+ HC production were 63.15% and 75.4%, respectively at 4u2009h TOS. The HDO result also showed that the CoOx/ZSM-5 has higher OA conversion of 92% compared to 59% over Co/ZSM-5. In addition CoOx/ZSM-5 showed higher HDO and isomerization activities compared to Co/ZSM-5.