The effect of Br- and alkali in enhancing the oxidation of furfural to maleic acid with hydrogen peroxide

This study was focused on investigating a novel catalytic system for the selective conversion of furfural to maleic acid (MA) in an aqueous system with hydrogen peroxide as an oxidant. A series of experiments that study the impacts of catalyst species, furfural concentration, catalyst dosage, reaction temperature, residue time, hydrogen peroxide concentration, excess water content, and solvent types on the oxidation of furfural to MA was carried out. The results showed that the co-existence of Br- and alkali sites might play a vital role in furfural oxidation, which could improve the MA yield remarkably. Under 90 ◦C for 3 h, 72.4 % MA yield was obtained with KOH and KBr as co-catalyst in an aqueous phase. Moreover, a possible reaction pathway of furfural oxidation was proposed on the basis of our reaction system

6 ‐ Chemo‐catalytic conversion of lignin

This chapter explains catalytic chemical methods of lignin transformation which include acidcatalyzed, base‐catalyzed and metal‐catalyzed methods. The chapter starts with a brief discussion of the lignin architecture as a background to understanding the subsequent subject of lignin’s chemocatalytic depolymerization methods. The general idea that lignin depolymerization involves the cleavage of the linkages holding its basic aromatic‐based monomers is discussed. Under each of the catalytic methods, the concept is first explained starting with the types of acid, base, or metal (as the case may be) employed, followed by the reaction conditions and then the reaction mechanism involved in method under discussion. Current research efforts are incorporated into each of the sections, as obtained from recent reviews. Under the metal‐catalyzed method, reductive and oxidative lignin depolymerization methods are explained. Extant challenges faced by lignin researchers are mentioned in the texts. A typical laboratory procedure for lignin depolymerization using the stainless steel autoclave is described, and the chapter ends with the future of lignin as a viable energy source and substitute for petroleum in the manufacture of chemicals and fuels

Evaluation of Blends of Agricultural Solid Biomass Waste for Solid Fuel Production

In this study, the calorific values of solid fuel samples and their blends in different proportions were determined. Waste samples as sawdust, charcoal, palm kernel bagasse, palm kernel shell, corn cob, palm fronds and coconut shell were subjected to combustion in an isothermal bomb calorimeter and their heating temperature profiles and corresponding heating values were estimated. Individual materials and different blending ratios in weight by weight (1:1, 1:1:1, 3:1:1, 1:3:1, and 1:1:3) heating contents were established. Burning time test was evaluated for blended materials with highest caloric values. Charcoal had the highest calorific value amongst all individual samples with a calorific value of 17,062 kJ/kg with palm fronds having the least heating value of 12,997 kJ/kg. In the 1:1 ratio mix, charcoal:palm oil bagasse had the highest heating content of 21,907 kJ/kg. Considering the ratios of three different solid mass in varying weight proportions, the combination of charcoal:coconut shell:palm oil bagasse (1:1:1) in equal weight percent gave the highest heating content of 23,373 kJ/kg. The blend of charcoal:coconut shell:palm kernel bagasse had the highest burning time of 20 minutes and 12 seconds. From the evaluations, charcoal in mixed proportions with other solid biomass are excellent materials to be considered for solid fuels production

Environment Quality in Nigeria: Implications for Poverty Reduction

Poverty in Nigeria is at extremely high levels and represents one of the many economic hardships faced by the Nigeria population. One of the factors potentially contributing to present high poverty levels is poor environment quality which is prevalent in Nigeria and which may result in increased poverty levels as efforts are undertaken to address adverse environment quality. This paper explored the effect of environment quality on poverty reduction in Nigeria using data from the World Bank World Development indicators over the period of 1990 to 2015. The study employed Augmented Dickey Fuller unit root test, and Autoregressive Distributed Lag (ARDL) estimation in analyzing data and the findings of the study revealed that improved environment quality as measured by improved access to sanitation and access to electricity positively and significantly increase poverty level in Nigeria, possibly on account of the increased financial and social costs of gaining access to sanitation and electricity. It is recommended that policy makers ensure that policies aimed at improving environment quality in Nigeria take into account the adverse implications of improving environment quality for poverty so as to ensure that a balance is achieved between improved environment quality and reduced poverty so that a cleaner environment is achieved at lower financial and welfare cost to citizens

Topside Pipeline Design for Slug Attenuation and Increased Oil Production

In oil and gas production system, slugging is frequently encountered when gas-liquid mixtures are transported through a common pipeline-riser system. This phenomenon usually manifests in significant fluctuation of flow and pressure which can impact the production system negatively. Topside choking is usually employed as a mitigation technique but with its attendant reduction in production capacity. The objective of this study therefore is to investigate the optimisation of topside pipeline diameter and choking for effective slug attenuation and optimised oil production. In this paper, a new method for slug flow attenuation has been proposed. The potential of using effective topside pipeline- diameter design for slug flow attenuation was theoretically shown. Numerical studies were also done to show that the concept can indeed be adapted for effective slug attenuation using an industrial software. Experimental studies were conducted in a 4” pipeline -riser system to validate the numerical and theoretical studies. The results showed that the optimised design of topside pipe diameter has potential for slug flow attenuation at larger valve opening which effectively translates to lower pressure and increased oil production. For the case studied, up to 49% reduction in the pressure drop across the topside choke valve was reported which practically implied increased flow capacity. An optimum volume which satisfied size, system stability and production constraints was obtained

Biodiesel Washing Water Treatment Using Zeolite and Activated Carbon as Adsorbents

Biodiesel production was produced from the transesterification of palm oil and methanol using KOH catalyst. The process variables considered are methanol to oil mole ratio of 4 – 6 and catalyst concentration of 0.2 – 1.0 wt/wt% Oil, at constant reaction temperature of 60℃ and constant reaction time of 60 minutes. Response surface plot showed that maximum yield of biodiesel (92 %) was obtained at 0.4 wt/wt% catalyst concentration and methanol/oil mole ratio of 7. The conventional activated carbon and zeolite produced were used separately as adsorbents in the treatment of biodiesel washing water. Comparatively, zeolite produced displayed better adsorption property compared to the conventional activated carbon in removing the six heavy metals considered from the biodiesel washing water. For instance, Chromium concentration of 0.0096 mg/L was reduced to 0.0023 mg/L after adsorption treatment with activated carbon (76 % efficiency), while the concentration was reduced to 0.0010 mg/L after the adsorption treatment with zeolite (89 % efficiency)

Experimental Investigation of Hydrodynamic Slug Flow in Pipeline-Riser Systems

Activities in oil and gas industry have shifted deep offshore. There is therefore the need to envisage and accurately provide for flow assurance challenges that might be encountered throughout the life of a field. Slug flow is one of the flow assurance concerns confronting the industry. The objective of the study was to gain insight into the behaviour of hydrodynamic slug flow in pipeline-riser system. This understanding is needed for the development of appropriate slug control strategy. Experimental studi es were conducted in a 2” pipeline-riser system and a 2” horizontal two -phase flow facility. Slug envelopes were developed for the pipeline-riser system, the vertical and the horizontal pipes. The results revealed three distinct slug flow behaviours. The first type of slug was formed in the horizontal pipeline and transported through the riser pipe nearly unchanged, the second type of slugs were formed in the horizontal pipe but also experience growth in the riser pipe while the third are slugs formed in the vertical pipe without the influence of the upstream horizontal pipe. There is therefore the need to develop appropriate slug control strategies based on the observed behaviour of the identified region

Irregularly Shaped NiO Nanostructures for Catalytic Lean Methane Combustion

NiO nanomaterials prepared using a solid–liquid NH3·H2O precipitation method (NiO-NSL) were tested in the catalytic combustion of methane. The NiO-NSL presented a characteristic rod-like nanostructure with a length of about a few hundred nanometers except for a part of the nanoparticles. For comparison, the NiO nanomaterials prepared by the traditional liquid-phase NH3·H2O precipitation method (NiO-NLL) were tested in the same reaction conditions. NiO-NSL exhibited significantly higher methane combustion activity than NiO-NLL and achieved the complete combustion of methane at 390 °C, which was outstanding in non-noble metal-based catalyst. X-ray photoelectron spectroscopy (XPS) and hydrogen-temperature-programmed reduction (H2-TPR) results indicate that the surface Ni2+ content of NiO-NSL was higher than that of NiO-NLL, and the presence of more Ni2+ might be responsible for the enhanced activity. DFT calculations prove that the energy barrier for C–H bond activation on Ni2+ was lower than that on Ni3+, which was consistent with the higher methane catalytic combustion activity of NiO-NSL. In addition, when the precipitating agent was replaced with NaOH and (NH4)2CO3, the generalization of the solid–liquid precipitation method in the preparation of the NiO catalysts was also tested. The results show that the solid–liquid precipitation method proposed in this work was still applicable when NaOH was used as a precipitant. However, with the use of (NH4)2CO3 as a precipitant, the methane catalytic activity of the NiO nanoparticles prepared by the solid–liquid precipitation method was reduced to a certain extent compared with the traditional liquid-phase precipitation method. This research can open up a highly efficient and environmentally friendly method for the synthesis of methane combustion catalysts

Passive Slug Attenuation Device: Potential and Operability

Over the years, there have been some concerted efforts towards developing techniques to mitigate the threat posed by slugs to oil and gas production systems. Passive slug attenuation devices have been known to show promising potential in this regard but can generally be confronted with operability issues. In this study, experimental investigation on the hydrodynamic slug attenuation potential and the operability of a process-intensified passive slug control device- Pseudo Spiral Tube (PST) was carried out. The result showed that the device possesses the capability to partially attenuate slug flow. This was achieved with the help of the swirl flow generated within the device which helps achieve air entrainments in the liquid slug leading to reduction in the effective density of the liquid slug. The results showed that the slug severity was reduced by 24% for the case studied. However, the slug redeveloped few meters downstream the device. Therefore, in order to achieve maximum slug attenuation, the device should be installed immediately upstream the topside separator. It was also observed that the pipeline might be pigged with the device installed. However, during multiphase flows, the pig may get stuck intermittently in the device. Hence, it was conceived that a flexible pig could be more appropriate to overcome this challenge