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African star apple seed husks, oil seed and whole seed were used for activated carbon production for the treatment and elimination of suspended and dissolved particles from industrial waste water. The activated carbon was produced using chemical activation method with phosphoric acid (H3PO4) and zinc chloride (ZnCl2) as the activating agents at a carbonization temperature of 500 °C. The morphological interpretations and functional groups of the activated carbon were observed using scanning electron microscopy and Fourier transform infrared spectroscopy respectively. Results obtained from the various pollution indicators showed an appreciably improvement on the quality of the water. The pH, temperature, total suspended solids, total dissolved solids and biological oxygen demand were determined with variation of the contact time of the activated carbons with the industrial wastewater. Seed husks of zinc chloride and Oil seed of phosphoric acid produced an activated carbon with the highest adsorptive performance for pH, temperature, Total Dissolved solids (TDS), Total suspended solids (TSS) and Biochemical oxygen demand (BOD) removal at 7.01, 7.14; 25.1 °C, 25.0 °C; 24.20 mg/L, 21.09 mg/L; 17.64 mg/L, 15.4 mg/L and 6.28 mg/L, 4.8 mg/L respectively at 150 min and yield of 75.2% and 54.3%.

The automotive industry is one major sector that consume material such as plastic at the advanced technological level. Hence, automotive plastics are now gaining attention due to the desire for light weight and low CO2 emission from vehicles. It is therefore anticipated that polymer nanocomposites will significantly enhance the performance of current technologies for car industries due to their excellent mechanical, chemical, thermal, electrical and barrier properties and their influence on fire retardancy. Hence, with the use of polymer nanocomposites, the encouraging outcomes in different sectors of automotive industry has resulted to new horizons in terms of advanced polymer nanocomposites for automobile applications. This chapter reviews advance polymer composites for automobile applications. Methods of fabricating polymer nanocomposites and several applications of polymer nanocomposites in automotive industries are discussed.

The inhibitive behaviour of aloe vera as an eco-friendly inhibitor was studied in the corrosion of mild and stainless steel in 0.5 M H2SO4 medium. The varied aloe vera inhibitor concentrations were studied using weight loss (gravimetric) and linear polarization methods. The methods showed that the inhibition efficiency increased with an increase in the concentration of the inhibitor (up to 10 vol/vol%) for both the mild and stainless steels. Stainless steel was found to exhibit a lower corrosion rate compared to mild steel. The results showed that Langmuir adsorption isotherm was obeyed by the inhibition of mild and stainless steel using aloe vera in 0.5 M H2SO4 with the values of the regression coefficients near unity. The negative values of ∆Gads show the spontaneous adsorption of inhibitor on the mild and stainless steel surfaces and a physisorption adsorption mechanism of the aloe vera inhibitor since the values of ∆Gads obtained are more than − 20 kJ/mol, that is, aloe vera is an efficient corrosion inhibitor with mixed-type inhibition property.

The biosorption process of Zn (II) ions in industrial wastewater was investigated using derived composite biosorbents from walnut and snail shells. Composite adsorbents were produced by activating walnut shell carbon (WSC) with phosphoric acid to obtain acid-treated walnut shell carbon (AWSC) and WSC and AWSC were independently impregnated on chitosan to produce walnut shell carbon impregnated on chitosan (WSCC) and acid-treated walnut shell carbon impregnated on chitosan (AWSCC) respectively. The removal efficiencies of Zn (II) ions from synthetic wastewater using the prepared adsorbents were determined. The effects of operational parameters on Zn (II) ions adsorption were investigated. The adsorption data of Zn (II) ions were analysed using Langmuir, Freundlich and Temkin isotherms. The Langmuir isotherm fitted the adsorption data excellently for the derived composite biosorbents, giving an indication of monolayer coverage on the derived composite biosorbents and the determination coefficients were close to unity. Also, the maximum adsorption capacities of 3.1104, 3.8052, 16.4474 and 17.6991 mg/g were obtained for WSC, AWSC, WSCC and AWSCC at pH=5, 1 g of adsorbent dosage, Zn (II) ions initial concentration of 30 mg/L, contact time of 2 h, agitation speed of 150 rpm, particle size of 60 BSS and temperature of 30°C. The kinetic modelling of Zn (II) ions adsorption showed that pseudo second-order kinetic model gave the best fit amongst the investigated kinetic models. The adsorption of Zn (II) ions on the prepared adsorbents was film-diffusion controlled. The experimental results of this study showed that acid-treated walnut shell carbon impregnated on chitosan has the potential to be applied as alternative efficient low-cost biosorbent in the remediation of heavy metal contamination in wastewater. The thermodynamic parameters indicated that the adsorption of Zn (II) ions on the derived composite biosorbents was exothermic, endogonic, favourable, non-spontaneous with changes in enthalpy (, negative), entropy [, nearly zero (though negative)], and Gibbs free energy (, positive), for all the prepared adsorbents. Key words: Adsorption, biosorbents, chitosan, isotherm, kinetic models, film diffusion.

A one-dimensional adiabatic mathematical model was developed for the riser reactor of an industrial residue fluid catalytic cracking unit (RFCCU). A seven-lump kinetic model was presented for the catalytic cracking of vacuum residue, taking cognisance of diffusion resistance, which is a departure from the general norm in the literature. Also, heat transfer resistance between the fluid and solid phases was incorporated into the energy balances for instantaneous and one-dimensional vaporization of feedstock. The developed model was a set of twelve coupled, highly non-linear and stiff ordinary differential equations, ODEs, which was numerically solved with an implicit MATLAB built-in solver, ode23t, designed deliberately for handling stiff differential equations to circumvent the problem of instability associated with explicit methods. An excellent agreement was achieved between the industrial RFCCU plant data and the simulated results of this study, with average absolute deviation being

Biodiesel was produced from the transesterification of soybean oil using calcium oxide and cow bone (an animal waste bone that contains hydroxyapatite, a calcium phosphate mineral) as heterogeneous catalysts. The soybean oil used was characterized using gas chromatography mass spectrometer (GCMS) and the cow bone catalyst produced was characterized using X-ray diffractometer (XRD) and X-ray fluorescence (XRF) spectrometer. The effects of the variation of methanol/oil mole ratio (9–15), catalyst concentration (10–20 wt/wt%) and reaction temperature (55–65 °C) on biodiesel yield during the transesterification of soybean oil with methanol was investigated. Reaction time of 3 hours and stirring rate of 500 rpm were kept constant. It was observed that the calcination of cow bone catalyst (at 800 °C) enhanced its conversion to apatite [Ca5(PO4)3OH] and increased the yield of biodiesel obtained. Biodiesel yield results revealed an optimum condition of methanol/oil mole ratio of 9, catalyst concentration of 15 wt/wt% and reaction temperature of 55 °C. Also, the results obtained showed that the performance trends of the two catalysts used were similar. And the close values of highest biodiesel yields obtained when the two heterogenous catalysts were used separately (yields of 94.8 and 92.2% using calcium oxide and calcined cow bone catalysts respectively) implies that the use of low-cost and readily available calcined cow bone catalyst is a promising alternative to CaO catalyst.

Corrosion inhibitor has been successfully used for the protection of 3CR12 stainless steel surface against corrosion in 1–2.5 M HCl. The performance of this inhibitor was correlated to the chemical composition and microscopic structures in accordance with the adsorption on the metal surface. Deoxyribonucleic acid (DNA) was extracted from the thymus gland of a calf, a component of the immune system of mammals. The study investigated the use of DNA extracted from calf thymus gland as a protective coat for 3CR12 stainless steel in the presence of a hydrochloric (HCl) medium. The mechanism of the potential inhibitor was understudied at different conditions of temperature and concentration in order to be able to explain the influence of the inhibitor on the metal. The highest CTGDNA inhibition efficiency was attained at 10 °C and at 20 mg/L. The micrographs revealed by scanning electron microscopy show that bio-macromolecules of CTGDNA were adsorbed on stainless steel surfaces. Nonetheless, the best micrograph result was achieved at 10 °C. The study of the Tafel polarization demonstrated that CTGDNA inhibitors at different concentration represented some mixed-type inhibitors. An inhibition mechanism was proposed which was confirmed by X-ray powder diffraction analysis. The results indicated that the corrosion inhibition efficiency increased with increase in HCl concentration.