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The design of active and selective co-catalysts constitutes one of the major challenges in developing heterogeneous photocatalysts for energy conversion applications. This work provides a comprehensive insight into thermally induced bottom-up generation and transformation of a series of promising Cu-based co-catalysts. We demonstrate that the volcano-type HER profile as a function of calcination temperature is independent of the type of the Cu precursor but is affected by changes in oxidation state and location of the copper species. Supported by DFT modeling, our data suggest that low temperature (200 °C) do not affect the Cu oxidation state, but induce a gradual, temperature-dependent surface-to-bulk diffusion of Cu, which results in interstitial, tetra-coordinated Cu+ species. The disappearance of Cu from the surface and the introduction of new defect states is associated with a drop in HER performance. This work examines electronic and structural effects that are in control of the photocatalytic activity and can be transferred to other systems for further advancing photocatalysis., Calcination of Cu/TiO2 is detrimental to its photocatalytic HER performance. We relate this to heat-activated Cu diffusion into the TiO2 lattice, which decreases accessibility of the Cu sites on the surface and generates charge recombination centers.

Systematic review investigating 3D-printing technologies for food production, for space and on Earth.

The Research has been conducted by analysis of heavy metal sea sediments concentrations of Lead (Pb), Copper (Cu), arsenic (As) and mercury (Hg) from Melawai Beach of Balikpapan, East Kalimantan. The research Method for all sample preparation is done by dry destruction, except for Hg analysis done by wet destruction then analyzed using Atomic Absorption Spectrophotometry (AAS) with specific wavelength for each metal. Concentrations were obtained from sediment of heavy metals Pb, Cu, As and Hg: Pb (λ max: 217.0 nm): 35.7504 to 41.4850 mg/kg; Cu (λ max: 253.7 nm): 16.0713 to 30.2314 mg/kg; As metal (λ max: 109.7 nm), 4.1406 to 5.3359 mg/kg; and Hg (λ max: 357.3 nm) from 0.8975 to 1.1991 mg/Kg, respectively. The analysis results of this research concluded that, the Melawai Balikpapan beach polluted with heavy metals, especially Pb, Cu, As and Hg.

Electrolytic water splitting using surplus electricity represents one of the most cost‐effective and promising strategies for hydrogen production. The high overpotential of the oxygen‐evolution reaction (OER) caused by the multi‐electron transfer process with a high chemical energy barrier, however, limits its competitiveness. Here, a highly active and stable OER electrocatalyst was designed through a cobalt‐induced intrastructural enhancement strategy combined with suitable electronic structure modulation. A carved carbon nanobox was embedded with tri‐metal phosphide from a uniform Ni−Co−Fe Prussian blue analogue (PBA) nanocube by sequential NH3 ⋅ H2O etching and thermal phosphorization. The sample exhibited an OER activity in an alkaline medium, reaching a current density of 10 mA cm−2 at an overpotential of 182 mV and displayed a small Tafel slope of 47 mV dec−1, superior to the most recently reported OER electrocatalysts. Moreover, it showed impressive electrocatalytic durability, increasing by approximately 2.7 % of operating voltage after 24 h of continuous testing. The excellent OER activity and stability are ascribed to a favorable transfer of mass and charge provided by the porous carbon shell, synergistic catalysis between the three‐component metal phosphides originating from appropriate electronic structure modulation, more exposed catalytic sites on the hollow structure, and chainmail catalysis resulting from the carbon protective layer. It is foreseen that this successfully demonstrated design concept can be easily extended to other heterogeneous catalyst designs., Make it better: This combined cobalt‐induced intrastructural enhancement and proper electronic structure modulation strategy is developed to fabricate a Ni−Co−Fe−P@CC‐E‐15 carved nanobox as a highly active and stable oxygen evolution electrocatalyst.

In Fluid Cokers, heavy oil is sprayed into a fluidized bed of hot particles through feed ring nozzles located at different heights. Unreacted or partially reacted feedstock, trapped in wet‑agglomerates, reaches the reactor bottom where it causes fouling or is lost to the system burner. The thesis objective is to determine whether modifying the feed distribution between rings or adding baffles can reduce the amount of liquid reaching the reactor bottom. A model was developed to predict the amount of liquid reaching the reactor bottom. It integrates models for agglomerate formation and rewetting in spray jets, agglomerate drying through heat transfer from the hot bed particles, and agglomerate breakage from shear in the turbulent bed. The model requires accurate agglomerate trajectories through the reactor to predict rewetting, drying time, and shear. Radioactive Particle Tracking (RPT) uses radioactive tracers to provide agglomerate trajectories in a 0.25 m diameter cold model with solid circulation. This thesis shows how RPT accuracy can be enhanced by correcting systematic errors from radiation absorption and random signal fluctuations due to the stochastic nature of radioactive emissions. The model shows that agglomerates between 10 and 13 mm in diameter are most likely to bring liquid to the reactor bottom. Smaller agglomerates dry quickly. Larger agglomerates are more likely to be broken through shear. Redistributing feed between rings can reduce the amount of liquid reaching the reactor bottom. Wet-agglomerates formed in the upper regions have more time to dry and break. For example, with five feed rings, redistributing the feed from the lower ring to the upper four rings reduces how much liquid reaches the reactor bottom by about 70-80%. Adding a ring-baffle in the bed can also reduce the amount of liquid reaching the reactor bottom by about 40-50%. The baffle prevents wet-agglomerates from reaching the reactor bottom quickly, providing more time for drying. The baffle also creates a zone of high shear between the baffle tips, enhancing agglomerate breakage. Combining baffle addition and feed redistribution from the lower ring to the upper feed rings reduces the amount of liquid reaching the reactor bottom by about 80-90%.

Global warming is now widely recognized as being the most significant global issue facing human beings. Mitigating CO2 emission from fossil-fueled power plants as well as from transports has become an urgent and worldwide research topic, in which CO2 separation is often needed. Technologies have been developed and commercialized, whereas the cost is still high. Developing new technologies for CO2 separation is one focus research area. Ionic liquids (ILs) are promising absorbents for CO2 separation due to their very low vapor pressure, high solubility and selectivity for CO2 as well as low energy usage for solvent regeneration. A drawback of using IL for CO2 separation is the high viscosities, and using supported ILs has been proposed as a promising solution. This can take advantage of the high selectivity of gas in ILs, and also the high surface area of materials can reduce the impact of viscosity, improve the gas transfer, and hence increase the absorption rate. To develop IL-based technologies, thermodynamic properties (density, heat capacity, gas solubility, etc.), viscosity, and surface tension of ILs as well as the thermodynamic properties for confined ILs are the prerequisites. As the number of ILs that can be theoretically synthesized is up to an order of 1018, determining all the properties experimentally is impractical, not to mention the time-consuming with high cost. It is desirable to develop theoretical tools to predict the thermodynamic and transport properties of ILs and IL-containing mixtures in a wide temperature and pressure range. In our previous work, the framework of ion-specific electrolyte perturbed-chain statistical associating fluid theory (ePC-SAFT) has been developed with reliable results. The developed ePC-SAFT model was further combined with Free Volume Theory (ePC-SAFT-FVT) and Density Gradient Theory (ePC-SAFT-DGT or DGT-ePC-SAFT) to represent the viscosity and surface tension of ILs, respectively. However, the work is limited to the imidazolium-based ILs, and the model performance for other commonly used ILs is still unclear. It has been pointed out that the model with the parameters fitted to the experimental data may result in pitfalls, and further validation is needed. Meanwhile, DGT-ePC-SAFT for pure ILs needs to be further developed to be consistent with the ion-specific ePC-SAFT model and extended to IL-mixtures. To describe the properties of confined ILs, in our previous work, ePC-SAFT model was combined with DFT (classical Density Functional Theory) (i.e., ePC-SAFT-DFT) to describe the properties of the IL and CO2/IL confined in nanopores. Still, the algorithm based on equal mesh width leads to intensive computations, making it inefficient. In this thesis, these ion-specific ePC-SAFT-based models were further developed and extended to the systems containing the ILs which are composed of the IL-cations ([Cnmim]+, [Cnpy]+, [Cnmpy]+, [Cnmpyr]+, and [THTDP]+) and the IL-anions ([Tf2N]-,[PF6]-, [BF4]-, [tfo]-, [DCA]-, [SCN]-, [C1SO4]-, [C2SO4]-, [eFAP]-, Cl-, [Ac]-, and Br-). Before modeling the properties, a method and scheme were developed to investigate the pitfall when modeling IL and IL-gas systems with ePC-SAFT. All 96 ILs considered in the thesis and their binary mixtures with CO2, H2S, CO, O2, CH4, N2, and H2 were covered. The results show that ePC-SAFT with the density-fitted parameters is virtually free of the undesired pitfall for almost all ILs with only one exemption ([C8mpy][BF4]) and the parameters for [Cnmpy]+ may need to be modified in future work. Afterward, ePC-SAFT was used to predict gas solubilities and second-order thermodynamic properties, such as heat capacities, isothermal and isentropic compressibilities, speeds of sound, thermal expansion coefficients, and internal pressures. The model predictions were evaluated by comparing with the experimental data, showing reliable results. ePC-SAFT-FVT was used to model the viscosities of ILs and IL-mixtures and compared with the available experimental data. It shows the model can represent the viscosity of pure ILs in a wide temperature and pressure range, and the parameters obtained from pure ILs can be used to predict the viscosity of IL-mixtures reliably. The model performance of Cl-based ILs at low temperatures is poor, and the temperature-dependent FVT parameter may be used to improve the model results. DGT-ePC-SAFT can provide reliable results for pure ILs in a wide temperature range, and it can be further used to describe the density profile in the interface. Furthermore, spot-DGT-ePC-SAFT based on the approximate density profile was proposed to predict the surface tension of IL-IL and IL-CO2 systems, and the reliable predictions imply the promising of spot-DGT-ePC-SAFT. To calculate the properties of confined ILs efficiently, Chebyshev pseudo-spectral collocation method was applied to accelerate the ePC-SAFT-DFT calculation. The feasibility of accelerating the ePC-SAFT-DFT calculation with the Chebyshev pseudo-spectral collocation method was discussed for the confined IL-CO2 systems. It was found that the Chebyshev pseudo-spectral collocation method can improve the efficiency of ePC-SAFT-DFT calculation significantly.

How to achieve high mass loadings while maintaining high energy and power densities together with slow self-discharge rates for aqueous asymmetric supercapacitors (AASCs) remains a great challenge. Herein, we tested an AASC using Ti3C2Tz MXene as the negative electrode, a mixture of manganese oxides, Mn3O4 and MnOOH, as the positive electrode with a saturated lithium chloride (14 M LiCl) electrolyte. This device, with electrode thicknesses of > 100 mu m, and a mass loading of similar to 10 mg cm(-2), resulted in an energy density of approximate to 30 Wh kg(-1) at 0.5 A g(-1), a power density of approximate to 23 kW kg(-1) at 20 A g(-1), an open cell voltage of 2.3 V, excellent rate capability and cycling stability. When allowed to self-discharge for 54 h at room temperature, similar to 66% of the voltage was retained. Crucially, after that time the cell voltage was > 1.5 V. This work opens a new opportunity for high performance, environmentally friendly AASCs, where high energy and power densities are combined with slow self-discharge rates at commercial mass loadings. Funding Agencies|Swedish Foundation for Strategic Research (SSF)Swedish Foundation for Strategic Research [EM16-0004]; Knut and Alice Wallenberg (KAW) foundation for a Fellowship/Scholar grant

The electrochemical exfoliation of graphite is one of the cheapest and most tunable industrial techniques to produce graphene nanosheets with a tunable degree of oxidation and solubility. Anodic oxidation allows high-yield production of electrochemically exfoliated graphene oxide (EGO) in either acid or salt solutions, with the key role played by ions electrochemically driven in between the graphene sheets. This chemical intercalation is followed by a mesoscale mechanical exfoliation process, which is key for the high yield of the process, but which is still poorly understood. In this work, we use Raman spectroscopy to simultaneously monitor the intercalation and oxidation processes taking place on the surface of highly ordered pyrolytic graphite (HOPG) during electrochemical exfoliation. The mechanism of EGO formation in either acidic (0.5 M H2SO4) or neutral (0.5 M Li2SO4) electrolytes through blistering and cracking steps is discussed and described. This process is also compared to the non-destructive intercalation of graphite in an organic electrolyte (1 M NaClO4 in acetonitrile). The results obtained show how high exfoliation yield and low defectivity can be achieved by the combination of efficient, non-destructive intercalation followed by chemical decomposition of the intercalants and gas production.

Dual-ion batteries (DIBs) generally operate beyond 4.7 V vs Li+/Li0 and rely on the intercalation of both cations and anions in graphite electrodes. Major challenges facing the development of DIBs are linked to electrolyte decomposition at the cathode–electrolyte interface (CEI), graphite exfoliation, and corrosion of Al current collectors. In this work, X-ray photoelectron spectroscopy (XPS) is employed to gain a broad understanding of the nature and dynamics of the CEI built on anion-intercalated graphite cycled both in highly concentrated electrolytes (HCEs) of common lithium salts (LiPF6, LiFSI, and LiTFSI) in carbonate solvents and in a typical ionic liquid. Though Al metal current collectors were adequately stable in all HCEs, the Coulombic efficiency was substantially higher for HCEs based on LiFSI and LiTFSI salts. Specific capacities ranging from 80 to 100 mAh g–1 were achieved with a Coulombic efficiency above 90% over extended cycling, but cells with LiPF6-based electrolytes were characterized by

Geldart Group C particles become increasingly attractive in industry because of their small particle sizes and large specific surface areas. The main challenge in the flow and fluidization of Geldart Group C particles is their cohesive nature due to strong interparticle forces. The “nanoparticle modulation” technique was adopted to reduce the interparticle forces of Group C particles and thus significantly improved their flow and fluidization quality. Group C+ particles, a new type of fine particles with drastically reduced or insignificant interparticle forces, were created using the nano-modulation technique. Fundamental studies provided a comprehensive understanding of the fluidization quality of Group C+ particles. Group C+ particles exhibited revolutionary advancements in fluidization, which enabled its pseudo-particulate fluidization over a wide range of operating gas velocities, up to 200%-300% times that of bed expansion. Group C+ particles also exhibited much higher dense phase expansion than Group A particles, indicating more gas holdup in the dense phase available for intimate gas-solid contact. Bubbling behaviors for Group C+ particles were further fully characterized, showing that bubbles were smaller in diameter, lower in rise velocity, and had a longer residence time in the Group C+ fluidized bed in comparison with the Geldart Group A fluidized bed. With more gas flow through the dense phase for Group C+ particles, the correction factor Y that accounts for increased dense phase gas flow in the modified two-phase theory was correlated to characterize the division of gas flow between the two phases for Group C+ particles, based on the experimental results. A theoretical method for predicting the dense phase voidage for Group C+ particles was also proposed. Furthermore, Group C+ particles were used as catalysts in a fluidized bed reactor (C-plus FBR) to evaluate the reaction performance and were compared to that using Group A particles. C-plus FBR achieved a much higher reaction conversion, up to 235% of that using Group A particles, and a higher contact efficiency, being 330% more than that for Group A particles. In summary, Group C+ particles exhibited extremely higher dense phase expansion, smaller bubbles and less bubble holdups, more gas flow through the dense phase, etc. enhancing the gas-solid contact and thus improving the reactor performance. Therefore, Group C+ fluidized bed reactor is expected to cause a significant “splash” in industrial processes, especially for gas-phase catalytic reactions.

Sandvik produces about 230 000 tonnes of steel annually by melting in an electric arc furnace, where more than 90% of this steel is casted via continuous casting. When the strands are cast, these strands will be cuts to specific lengths with 2 cm thick cuts by using gas and iron powder. This generates approximately 750 tonnes of steel chips (cutting residues) each year, with a composition from the entire annual production of steel that falls as a residual. The purpose of the work was to review a possible reuse of the cutting residues as a raw material in the electric arc furnace. The problem with the cutting residue is the large reactive surface area, which could cause the material to burn in the electric arc furnace during operation. Since there are a high gas flow in the electric arc furnace during operation, the cutting residue that has a small particle size can also disappear from the furnace with the gas flow to the particle filters. By briquetting the cutting residue, these problems could be minimized and a reuse of the cutting slag as raw material could thus be possible. Therefore the cutting residue was transported to a company that sieved, dried and briquetted the cutting residue. 37 tonnes of cutting residue briquettes have been reused into 18 charges under normal operations with 2 tonnes of cutting residue briquettes in each charge (one charge with only 1 tonne of cutting slag). In order to measure how efficient, the reuse of the cutting residue was, a reference was needed. The reference was based on how the yield of steel for the elements, molybdenum, nickel, copper, cobalt and chromium in the electric arc furnace behaves in daily operation. This yield was used as a basis for calculating the yield when reusing the cutting residue. The results showed that nickel and molybdenum had a consistently good yield. The results for the cobalt and copper was not as clear, but the yields were generally good. In the case of chromium the results are naturally varied, as chromium reacts with the slag during the process. However, the predominant conclusion of the work was that it is possible to reuse the cutting residue as a raw material in the electric arc furnace with an acceptable yield by briquetting it. Analysis of the slag was also done to see any deviations from daily operations. The results showed that the slag was not affected when the cutting residue was reused as raw material in the electric arc furnace. Varje år producerar Sandvik ungefär 230 000 ton stål genom nedsmältning av stålskrot i ljusbågsugnen där mer än 90 % av stålet gjuts via stränggjutning. När strängarna gjuts kapas de till specifika längder med ett 2 cm tjockt snitt med hjälp av syrgas och järnpulver. Detta resulterar i en restprodukt (skärslagg) om ca 750 ton per år, med sammansättningen från den årliga produktionen av stål. Syftet med arbetet var att se över en möjlig återanvändning av skärslaggen som råvara i ljusbågsugnen. Problematiken med skärslaggen är den stora reaktiva ytan vilket kan medföra att materialet börjar brinna i ljusbågsugnen under drift. Skärslaggen har en liten partikelstorlek och kan således följa med till gas- och partikelfilter då det är ett högt gasflöde i ljusbågsugnen under drift. Genom att brikettera skärslaggen kan dessa problem minimeras och en återföring av skärslaggen som råvara kan således vara möjlig. Skärslaggen transporterades till ett företag som siktade, torkade och briketterade skärslaggen. 37 ton skärslaggsbriketter har återförts i 18 försökscharger under normal drift med 2 ton skärslaggsbriketter i varje charge (en charge med enbart 1 ton skärslagg). För att mäta hur effektivt återföringen av skärslaggen var behövdes en referensnivå. Referensnivån baserades på hur utbytet till stål för elementen, molybden, nickel, koppar, kobolt och krom i ljusbågsugnen förhåller sig vid daglig drift. Detta utbyte användes som bas för att beräkna utbytet vid återföringen av skärslaggen. Av resultaten framgår det att nickel och molybden visade genomgående goda utbyten. Utfallet för elementen kobolt och koppar var inte lika tydliga men utbytena var till övervägande del goda. Beträffande krom var resultaten av naturliga skäl varierande, då krom reagerar med slaggen under processens gång. Den övervägande slutsatsen av arbetet var emellertid att det går att återföra skärslagg som råvara i ljusbågsugnen med godtagbara utbyten genom att brikettera den. Analysering av ljusbågsugnsslaggen gjordes också för att se eventuella avvikelser ifrån den dagliga driften. Resultaten visade att slaggen inte påverkas när skärslaggen återförs som råvara i ljusbågsugnen.

Carbamazepine (CBZ), a widely used pharmaceutical compound, is one of the most detected drugs in surface waters. The purpose of this work was to identify an active and durable catalyst, which, in combination with an ozonation process, could be used to remove CBZ and its degradation products. It was found that the CBZ was completely transformed after ozonation within the first minutes of the treatment. However, the resulting degradation products, 1-(2-benzaldehyde)-4-hydro-(1H,3H)-quinazoline-2-one (BQM) and 1-(2-benzaldehyde)-(1H,3H)-quinazoline-2,4-dione (BQD), were more resistant during the ozonation process. The formation and degradation of these products were studied in more detail and a thorough catalytic screening was conducted to reveal the reaction kinetics of both the CBZ and its degradation products. The work was performed by non-catalytic ozonation and with six different heterogeneous catalysts (Pt-MCM-41-IS, Ru-MCM-41-IS, Pd-H-Y-12-EIM, Pt-H-Y-12-EIM, Pd-H-Beta-300-EIM and Cu-MCM-41-A-EIM) operating at two temperatures 20 &deg, C and 50 &deg, C. The influence of temperature on degradation kinetics of CBZ, BQM and BQD was studied. The results exhibited a notable difference in the catalytic behavior by varying temperature. The higher reactor temperature (50 &deg, C) showed a higher activity of the catalysts but a lower concentration of dissolved ozone. Most of the catalysts exhibited higher removal rate for BQM and BQD compared to non-catalytic experiments in both temperatures. The Pd-H-Y-12-EIM catalyst illustrated a higher degradation rate of by-products at 50 &deg, C compared to other catalysts.

The remediation of metal-contaminated natural water bodies is prioritized due to metals toxicity, non-biodegradable properties, and accumulative behaviours leading to the increased incidence of adverse health effects. Current investigation is driven by the existing problem of elevated aluminum concentrations in the groundwater of Khibiny alkaline massif (Kola Peninsula). The prohibitive aluminum level exceeding the accepted standard of 0.20 mg L−1 is described as a serious health concern when the groundwater used for the local water supply. The results of comprehensive field data analysis based on chemometric methods applied to the available monitoring data including 12 groundwater quality parameters are reported as well as the outcomes of laboratory study on aluminum adsorption from aqueous solutions. Computed correlation coefficients matrix revealed a statistically significant level of associations between aluminum concentrations and pH values, concentrations of SO42−, NO3−, Cl−. Mathematical models developed by using univariate and multivariate regression methods explained up to 54% of aluminum concentration temporal variability linked to pH, Cl−, NO3− and up to 67.5% of the original dataset total variance. The outcomes of hierarchical cluster analysis suggested data subdivision into three clusters where Al and pH formed a separate cluster. The frequency bands describing dominant variability features of groundwater quality parameters were identified by spectral analysis based on fast Fourier transform algorithm and corresponded approximately to 5–7, 13–17, and 20–34 month periods. Calculated CCME water quality index scores identified a groundwater quality gradual deterioration from fair to marginal category during the monitoring period 1999–2012. Laboratory study of aluminum removal on adsorbents from aqueous solutions considering water-specific natural conditions showed the maximum aluminum uptake of 1.69 mg g−1 by montmorillonite K10 within 120 min at pH 4.0 while TiO2 and vermiculite concrete-supported ferric oxyhydroxide adsorbent were most effective at pH 9.0 obtaining maximum adsorption capacities of 6.85 mg g−1 and 6.75 mg g−1 in 30 min and 240 min, respectively. It was shown that when these two adsorbents worked jointly the capacity reached 8.28 mg g−1 within 60 min at pH 9.0. The changes of each component mass allow controlling contact time to provide required aluminum removal efficiency. No apparent significant effect on aluminum removal by adsorbents tested in the presence of SO42−, NO3−, Cl− was observed at pH 9.0. The current study identifies a possible approach and the reliable foundation of water treatment technology solving the problem of elevated aluminum concentrations in the household water of Khibiny alkaline massif area as well as other locations where the solution of this problem can improve living conditions or industrial technologies.

For a hydrogen economy to be viable, clean and economical hydrogen production methods are vital. Electrolysis of water is a promising hydrogen production technique with zero emissions, but suffer from relatively high production costs. In order to make electrolysis of water sustainable, abundant, and efficient materials has to replace expensive and scarce noble metals as electrocatalysts in the reaction cells. Herein, we study activated stainless steel as a bi-functional electrocatalyst for the full water splitting reaction by taking advantage of nickel and iron suppressed within the bulk. The final electrocatalyst consists of a stainless steel mesh with a modified surface of layered NiFe nanosheets. By using a top down approach, the nanosheets stay well anchored to the surface and maintain an excellent electrical connection to the bulk structure. At ambient temperature, the activated stainless steel electrodes produce 10 mA/cm2 at a cell voltage of 1.78 V and display an onset for water splitting at 1.68 V in 1M KOH, which is close to benchmarking nanosized catalysts. Furthermore, we use a scalable activation method using no externally added electrocatalyst, which could be a practical and cheap alternative to traditionally catalyst-coated electrodes.

In this study, we incorporate a copper impurity into (Co3O4) nanowires precursor that turn them into an active catalyst for the hydrogen evolution reaction in 1M KOH. The XRD and XPS results are in good agreement and confirmed the formation of Co3O4-CuO nano composite by wet chemical method. To date, the performance of hydrogen evolution reaction in alkaline for the composite catalyst is comparable or superior to cobalt oxide based HER electro-catalysts. The HER catalyst exhibits the lowest Tafel slope of 65 mVdec(-1) for the cobalt-based catalysts in alkaline media. A current density of 10 mA/cm(2) is achieved at a potential of 0.288 V vs reversible hydrogen electrode (RHE). The mixed transition metal oxide Co3O4-CuO based HER electro-catalyst is highly stable and durable. The EIS results demonstrates that HER is highly favorable on the Co3O4-CuO due to the relatively small charge transfer resistance (173.20 Ohm) and higher capacitance values (1.97 mF). (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Earth-abundant transition metal-based compounds are of high interest as catalysts for sustainable hydrogen fuel generation. The realization of effective electrolysis of water, however, is still limited by the requirement of a high sustainable driving potential above thermodynamic requirements. Here, we report dynamically self-optimized (DSO) NiFe layered double hydroxide (LDH) nanosheets with promising bi-functional performance. Compared with pristine NiFe LDH, DSO NiFe LDH exhibits much lower overpotential for the hydrogen evolution reaction (HER), even outperforming platinum. Under 1 M KOH aqueous electrolyte, the bi-functional DSO catalysts show an overpotential of 184 and -59 mV without iR compensation for oxygen evolution reaction (OER) and HER at 10 mA cm(-2). The material system operates at 1.48 V and 1.29 V to reach 10 and 1 mA cm(-2) in two-electrode measurements, corresponding to 83% and 95% electricity-to-fuel conversion efficiency with respect to the lower heating value of hydrogen. The material is seen to dynamically reform the active phase of the surface layer during HER and OER, where the pristine and activated catalysts are analyzed with ex situ XPS, SAED and EELS as well as with in situ Raman spectro-electrochemistry. The results show transformation into different active interfacial species during OER and HER, revealing a synergistic interplay between iron and nickel in facilitating water electrolysis.

Cellulose–chitosan films were prepared using a physical method in which cellulose and chitosan were separately dissolved via freeze thawing in LiOH/urea and mixed in different proportions, the resulting films being cast and regenerated in water/ethanol. X-ray diffraction and Fourier transform infrared spectroscopy (FT-IR) spectroscopy verified the composition changes in the nanocomposites due to different mixing ratios between the polymers. Tensile stress–strain measurements indicated that the mechanical performance of the cellulose–chitosan nanocomposites slightly worsened with increasing chitosan content compared with that of films comprising cellulose alone. Field emission scanning electron microscopy revealed the spontaneous formation of nanofibers in the films; these nanofibers were subsequently ordered into lamellar structures. Water uptake and microscopy analysis of film thickness changes indicated that the swelling dramatically increased at lower pH and with increasing chitosan content, this being ascribed to the Gibbs–Donnan effect. Slow material loss appeared at acidic pH, as indicated by a loss of weight, and quantitative FT-IR analysis confirmed that chitosan was the main component released. A sample containing 75% chitosan reached a maximum swelling ratio and weight loss of 1500% and 55 wt%, respectively, after 12 h at pH 3. The study presents a novel way of preparing pH-responsive cellulose–chitosan nanocomposites with slow-release characteristics using an environmentally friendly procedure and without any chemical reactions.

Effective and economical carbon dioxide-methane separation (CO2/CH4) is highly desirable in several industries such as sweetening natural gases and renewable natural gas (RNG) from biogas and landfills. Among the different separation technologies, membrane separation has been shown to have lower cost of production and lower CH4 losses. In this study, Zeolitic Imidazole Frameworks (ZIF-8) crystals with sizes varying from 45 nm to 450 nm were synthesized and incorporated in the polymer of intrinsic microporosity, PIM-1, to form mixed matrix membranes (MMMs). The structure, morphology, and physicochemical properties of the MMMs were characterized by 1H NMR, FTIR, XRD, TGA, and SEM. ZIF-8 crystal size was controlled using the concentration of sodium formate. The influence of the ZIF-8 crystal size on MMMs was studied by sorption, gas permeability, and aging of the membranes. The MMMs with ZIF-8 crystals of 120 nm particle diameter yielded the greatest improvement in gas transport properties; the CO2/CH4 selectivity-CO2 permeability was 11.4 and 9700 Barrer compared to PIM-1 with 6.4 and 9300 Barrer respectively. The former is near the Robeson 2008 upper bound, while PIM-1 is on the 1991 upper bound. After 40 days of aging, selectivity increased and permeability decreased; the changes were parallel to the Robeson upper bounds indicating increased polymer packing and diffusivity selectivity.

Polar polythiophenes with oligoethylene glycol side chains are exceedingly soft materials. A low glass transition temperature and low degree of crystallinity prevents their use as a bulk material. The synthesis of a copolymer comprising 1) soft polythiophene blocks with tetraethylene glycol side chains, and 2) hard urethane segments is reported. The molecular design is contrary to that of other semiconductor‐insulator copolymers, which typically combine a soft nonconjugated spacer with hard conjugated segments. Copolymerization of polar polythiophenes and urethane segments results in a ductile material that can be used as a free‐standing solid. The copolymer displays a storage modulus of 25 MPa at room temperature, elongation at break of 95%, and a reduced degree of swelling due to hydrogen bonding. Both chemical doping and electrochemical oxidation reveal that the introduction of urethane segments does not unduly reduce the hole charge‐carrier mobility and ability to take up charge. Further, stable operation is observed when the copolymer is used as the active layer of organic electrochemical transistors., A soft polythiophene with tetraethylene glycol side chains is copolymerized with hard urethane blocks. The copolymer exhibits improved ductility and stiffness, owing to a reversible network formed through hydrogen‐bonding between urethane segments, while electrical and electrochemical properties are retained to a great extent. The hydrogen‐bonded network reduces the degree of swelling of the copolymer as compared to the homopolymer.

Potensi spons Indonesia mencapai 80 persen dari populasi spons dunia. Spons adalah jenis hewan paling unik di dunia. Spons merupakan hewan kecil yang diklaim paling tua di dunia. Potensi pemanfaatan spons sangat luas terutama pemanfaatan kanduangan zat aktif dalam bidang kesehatan, pemanfaatan mikrosimbion dan biomassa dalam bidang pengolahan limbah hidrokarbon sebagai biodegradator dan penanganan limbah logam berat dengan metode bioabsorpsi, serta potensi pengembangan ekstrak sebagai anti bakteri pathogen, biomaterial pada cat, serta potensi zat berperilaku enzim untuk mengatasi keretakan pada tembok, adalah bagian dari sekian banyak pemanfaatan spons. Eksplorasi spons untuk mencapai hasil maksimal, membutuhkan kolaborasi berbagai pihak dapat menjadikan spons sebagai objek riset masa depan oleh para peneliti handal Indonesia dan dunia.Eksplorasi spons itu membutuhkan berbagai pengetahuan, kreativitas, wawasan dan metode serta kearifan dalam melakukannya untuk tujuan penerapan dan pengembangan, serta dibutuhkan kolaborasi berbagai disiplin ilmu, peran regulasi pemerintah dan berbagai komitmen investasi untuk menuju pada hasil nyata berupa produk inovasi pada banyak bidang. Hal ini menjadikan spons sebagai hewan yang penting dan patut dilingdungi bahkan kedepan bisa jadi merupakan hewan langka yang dikejar-kejar oleh manusia. Upaya pelestarian spons dengan melakukan transplantasi, regulasi kawasan konservasi, zona perlindungan adalah usaha untuk menjaga kelestarian spons di habitat alaminya agar terhindari dari ancaman kepunahan karena banyaknya predator dan ancaman hancurnya populasi spons karena ulah manusia dalam usaha penangkapan yang kerap kali menggunakan bom/ racun ikan, aktivitas reklamasi pantai yang saat ini menjadi tren dan mungkin juga karena pengembangan kawasan dalam usaha wisata yang dikelola tidak bijak. Gugusan Kepulauan Spermonde di Sulawesi Selatan, Kepulauan Seribu di Jakarta dan kawasan Laut Bunaken adalah area yang dapat dijadikan sebagai kawasan zonanisasi biota laut termasuk spons.

Molecular characterization studies have been conducted 16S rRNA gene micro symbiont of sponge origin Melawai Beach, Balikpapan in East Kalimantan. Objective analysis of histo- morphological research, isolation-purification, molecular characterization of micro-symbiont genes in order to search symbiont bacteria that can live in extreme environments contaminated hydrocarbon waste. The research method that morphological identification, isolation-purification and molecular characterization of the 16S rRNA gene with Chain Reaction Polymerization method. The results of histo-morphological analysis concluded sponge samples with species of Callyspongia sp. Isolation and purification mikro symbionts of sponge obtained 2 (two) isolates. Characteristics of Isolates 1; spherical shape, colonize and creamy, while isolates 2; jagged shape, oval and white colonies. Molecular characterization of the 16S rRNA gene by PCR, Bacillus subtilis strain BAB-684 identification for isolates one is the number of nucleotide pairs reached 899 bp and the degree of similarity in GenBank reached 89% homologous, while the second is a Bacillus flexus strain PHCDB20 isolates the number reached 950 bp nucleotide pairs with the degree of similarity in GenBank reached 99% homologous

Supervision, control and constructive action by applying liquid waste quality standards to the mining industry that produces heavy metal wastewater must be done to prevent environmental pollution, material loss and health impact to surrounding communities. The analysis of the liquid waste generated by the mining industry aims to ensure the application of environmental quality standard requirements by each industry using measurement method and parameter analysis of acidity degree using Oakton pH meter, total solid, Chromium hexavalent (Cr6+) of concentration using HACH DR 2000, and Nickel (Ni) of dissolved using ICP-OES Spectrophotometer. Results obtained respectively: The average acidity (pH) of the sample (SP1) averaged pH 8.35 and sample (SP4) averaged pH 8.92. Highest total sample (SP1) solids, 864 mg/L and lowest, 136 mg/L, while sample (SP4), highest, 1.280 mg/L and lowest, 174 mg/L. Concentrations of Chromium Hexavalent (Cr6 +) samples (SP4), 0.91 mg/L and samples (SP1), 0.01 mg/L. Mean Soluble Nickel (SP1) average concentration, 0.08 mg/L, and sample (SP4), 0.07 mg/L. Based on the results obtained concluded that both types of waste water samples PT. Vale Tbk, Soroako, meets four variables that are analyzed in liquid waste quality standard.

The research has been done about isolation and identification on degradator bacterium of petroleum waste which symbions with sponge from Melawai Beach, Balikpapan. The research objectives; knowing sponge species, symbioning bacterium isolate and its ability of petroleum waste degradation. The research method were analysis of sponge Morphology analysis, isolation of symbions bacterium, identification, and activity testing at petroleum waste media which is coming from wells result of processing of PT. Chevron. The research result obtained the morphology analysis concluded that the sponges is Callyspongia sp. Bacterium symbion isolation obtained that two isolates which were given each symbols isolate A with the rounded shape and crem color whereas isolate B with yellow color and jagged shape. Coloring analysis of isolate obtained that isolate A is negative gram bacterium type and isolate B is positive gram bacterium type. Activity isolate testing at petroleum waste media, isolate A did not grow significantly at the media which marked with the existence of layer transparent on the media, isolate B growth significantly which marked with existence of solidity on the media, and the combination of isolate A+B also showed growth which marked with the existence of layer transparent and solidity on media. The conclusions research, sponge species is Callyspongia sp which contained two isolates bacterium namely negative gram bacterium and positive gram bacterium and both of the isolates can grow at media of petroleum waste.

Has been conducted research about isolation and identification bacterium symbionts sponge as producer enzyme amylase from Melawai Beach of Balikpapan. Targeting know is sponge type, symbionts bacterium group and test ability of sponge symbionts bacterium as amylase enzyme producer. Research expected to give information about existence of sponge and micro symbioning it’s from Melawai Beach. Research executed in four phase namely analysis sponge morphology, macroscopic analysis of isolate, microscopic analysis through coloration of bacterium symbionts, and test ability of symbion bacterium in yielding amylase enzyme. Result of morphology analysis is Callyspongia sp species enter in Callyspongiidae of family relatives, while perceived by microscopic and macroscopic perception of symbion bacterium in form of small bar, ellipse, surface flatten, colony disseminate, ruddle, fastening safranin colour designate the bacterium is negative gram. Perception of activity amylase enzyme at MA medium show colony have amylase activity marked with formed it’s of transparent zone at MA media colony if dropped by iodium condensation. Activity of amylase very high happened it thinning 10-2 marked with the existence of formed by zone of transparent very wide of around colony. Result of research concluded that t sponge is Callyspongia sp species, symbionts bacterium group is negative gram and bacterium represent producer of amylase enzyme

Determination biomass and phenotypic analysis of microsymbionts sponge is a comprehensive effort to discover the specificity of the sponge, not only on the identification and characterization studies that have been growing. Research directed at diversification of knowledge of the functions and benefits of a sponge for the life and welfare of mankind. The purpose of this research is the analysis of biomass morphology and phenotype test microsymbionts sponge. Histomorfologi analysis method to determine the type, components and composition biomass. Isolates obtained by sponge microsymbiont isolation- purification followed by phenotypic analysis through Gram staining and biochemical tests. Histomorfologi analysis results obtained sponge species is Callyspongia sp. Components and composition consists of sponge biomass fraction skeleton (spicules and cell debris) reached 69.8 %, 18.8 % sponge cell fraction and 11.3 % bacterial pellet fraction. The results of the isolation-purification microsymbiont obtained two isolates. Staining test results both isolates are Gram-positive bacteria and biochemical tests is Bacillus subtilis isolates the spherical shape large size, beige and white, while the isolates two clustered colonies are bacillus flexus jagged shape elongated, white-purple color and a separate colony

Gas condensates are liquid mixtures of high-boiling hydrocarbons of various structures, separated from natural gases during their production at gas condensate fields. When transporting gas through pipelines, the following gas quality conditions should be met:i.During transportation, gases should not cause corrosion of pipelines, fittings, instruments, etc.ii.The quality of the gas must ensure its transportation in a single-phase state i.e., liquid hydrocarbons, gas condensates and hydrates should not form in the pipelines.In order for gas condensates to meet the above-mentioned quality conditions during storage or transportation, they must be stabilized. Gas condensate stabilization is the process of “boiling off” light hydrocarbons from the condensate that would otherwise increase the vapor pressure when conditions are fluctuating.

The enrichment of CO 2 -reducing microbial biocathodes is challenging. Previous research has shown that a promising approach could be to first enrich bioanodes and then lower the potential so the electrodes are converted into biocathodes. However, the effect of such a transition on the microbial community on the electrode has not been studied. The goal of this study was thus to compare the start-up of biocathodes from preenriched anodes with direct start-up from bare electrodes and to investigate changes in microbial community composition. The effect of three electrode materials on the long-term performance of the biocathodes was also investigated. In this study, preenrichment of acetate-oxidizing bioanodes did not facilitate the start-up of biocathodes. It took about 170 days for the preenriched electrodes to generate substantial cathodic current, compared to 83 days for the bare electrodes. Graphite foil and carbon felt cathodes produced higher current at the beginning of the experiment than did graphite rods. However, all electrodes produced similar current densities at the end of the over 1-year-long study (2.5 A/m 2 ). Methane was the only product detected during operation of the biocathodes. Acetate was the only product detected after inhibition of the methanogens. Microbial community analysis showed that Geobacter sp. dominated the bioanodes. On the biocathodes, the Geobacter sp. was succeeded by Methanobacterium spp., which made up more than 80% of the population. After inhibition of the methanogens, Acetobacterium sp. became dominant on the electrodes (40% relative abundance). The results suggested that bioelectrochemically generated H 2 acted as an electron donor for CO 2 reduction. IMPORTANCE In microbial electrochemical systems, living microorganisms function as catalysts for reactions on the anode and/or the cathode. There is a variety of potential applications, ranging from wastewater treatment and biogas generation to production of chemicals. Systems with biocathodes could be used to reduce CO 2 to methane, acetate, or other high-value chemicals. The technique can be used to convert solar energy to chemicals. However, enriching biocathodes that are capable of CO 2 reduction is more difficult and less studied than enriching bioanodes. The effect of different start-up strategies and electrode materials on the microbial communities that are enriched on biocathodes has not been studied. The purpose of this study was to investigate two different start-up strategies and three different electrode materials for start-up and long-term operation of biocathodes capable of reducing CO 2 to valuable biochemicals.

Investigation of PAHs reshuffle by microorganisms has been done, but using sponge symbionts for the purpose of reduction of PAHs toxicity into simple organic compounds is still small. Microorganisms and sponges are known as complex animals that have various functions including the ability to produce bioactive compounds that can interact with hydrocarbon compounds as carbon sources. The purpose of this experiment was the use of bacteria isolated from seawater and sponges to reduce pyrene by biodegradation method by interacting between bacteria Alcaligenes faecalis strain Cu4-1 (AF), Bacillus subtilis strain BAB-1684 (BS) and Bacillus Cereus strain MER-8 (BC) capable of producing enzymes to overhaul the pyrene structure acting as a substrate. Biodegradation was carried out for 25 days, every 5 days to check degradation media using spectrophotometer and GC-MS to analyze degradation parameters: (1) optical density, (2) component abundance, (3) concentration and degradation rate of pyrene, and (4) ) Degraded organic of components. The results of the analysis of each degradation parameter were concluded: isolates, AF, BS and BC were able to degrade pyrene compounds, biodegradation rate: AF (97, 65%) ˃ BC (95, 27%) ˃ BS (93, 15%). Marine-filled bacteria (AF and BC) have a relatively higher pyrene degradation ability than the BS microsimbiont isolated on Callyspongi sp. Biodegradation of organic components results isolates AF and BC is different from the organic component isolates BS biodegradation results indicate that there is a specific mechanism which is owned by each type of bacteria to degrade PAHs

A structural lithium ion battery is a material that can carry load and simultaneously be used to store electrical energy. We describe a path to manufacture structural positive electrodes via electrophoretic deposition (EPD) of LiFePO4 (LFP), carbon black and polyvinylidene fluoride (PVDF) onto carbon fibers. The carbon fibers act as load-bearers as well as current collectors. The quality of the coating was studied using scanning electron microscopy and energy dispersive X-ray spectroscopy. The active electrode material (LFP particles), conductive additive (carbon black) and binder (PVDF) were found to be well dispersed on the surface of the carbon fibers. Electrochemical characterization revealed a specific capacity of around 60–110 mAh g−1 with good rate performance and high coulombic efficiency. The cell was stable during cycling, with a capacity retention of around 0.5 after 1000 cycles, which indicates that the coating remained well adhered to the fibers. To investigate the adhesion of the coating, the carbon fibers were made into composite laminae in epoxy resin, and then tested using 3-point bending and double cantilever beam (DCB) tests. The former showed a small difference between coated and uncoated carbon fibers, suggesting good adhesion. The latter showed a critical strain energy release rate of ∼200–600 J m−2 for coated carbon fibers and ∼500 J m−2 for uncoated fibers, which also indicates good adhesion. This study shows that EPD can be used to produce viable structural positive electrodes. QC 20180530

The aim of the project was to develop a method to measure and studythe degree of activation of the negative electrode (MH) in a NiMH battery.This was done by characterization of the gases produced during charge of a battery – O2 and H2 – using a Gas Chromatograph. The current applied in the very first charge of the battery was varied in order to examine how this affects the gas evolution. In the developed method, batteries were charged to 8Ah with 9A, after which a gas sample was taken and analyzed with Gas Chromatography. An additional goal was to use the method to examine the difference in activation between virgin and recycled negative electrode material. A module charged stepwise with 0.07C followed by 0.2C had the lowest share of H2 after two cycles, indicated best activation. However, a higher amount of H2 in the beginning of the activation process could possibly enhance the degree of activation during the following cycles. The method indicated that the module with recycled MH was better activated than the virgin MH. To improve the technique, repeated measurements to get better statistics should be done. Gas samples should be taken at dV/dt=0 in order to take samples at same SoC. The charge current should be adjusted so that the same C rate is always used. This would make the results easier to interpret.

Solar-to-chemical conversion of sunlight into hydrogen peroxide as a chemical fuel is an emerging carbon-free sustainable energy strategy. The process is based on the reduction of dissolved oxygen to hydrogen peroxide. Only limited amounts of photoelectrode materials have been successfully explored for photoelectrochemical production of hydrogen peroxide. Herein we detail approaches to produce robust organic semiconductor photocathodes for peroxide evolution. They are based on evaporated donor-acceptor heterojunctions between phthalocyanine and tetracarboxylic perylenediimide, respectively. These small molecules form nanocrystalline films with good operational stability and high surface area. We discuss critical parameters which allow fabrication of efficient devices. These photocathodes can support continuous generation of high concentrations of peroxide with faradaic efficiency remaining at around 70%. We find that an advantage of the evaporated heterojunctions is that they can be readily vertically stacked to produce tandem cells which produce higher voltages. This feature is desirable for fabricating two-electrode photoelectrochemical cells. Overall, the photocathodes presented here have the highest performance reported to date in terms of photocurrent for peroxide production. These results offer a viable method for peroxide photosynthesis and provide a roadmap of strategies that can be used to produce photoelectrodes with even higher efficiency and productivity. Funding Agencies|Knut and Alice Wallenberg Foundation; Wallenberg Centre for Molecular Medicine at Linkoping University; Vinnova within the framework of Treesearch.se

The toxicity of petroleum sludge is a serious threat to marine life. Necessary concrete steps petroleum contamination reduction through a search of potential marine materials degrade toxic components hydrocarbons. The sponge is one potential material reducing toxic properties of petroleum contamination. The research objective was to determine the potential Callyspongia sp sponge against the degradation of petroleum hydrocarbon sludge. Four variations of treatment used to determine the potential of sponge biomass, namely: the treatment I, II, III and IV. Indicators degradation is the formation of gas, the smell fermentation, pH changes and increase in the absorbance of the suspension of media degradation. The level degradation each treatment is determined gravimetric method and the known hydrocarbon component changes by using GC-MS. Unidentified gas, the smell of fermentation and changes in media of pH on average degradation occurs on the 15 days of contact for all treatments. Data showed degradation occurs absorbance maximum at 20- 25 days to contact. The highest degradation rates indicated by IV treatment (26.93 %), III (24.84 %), II (22.59 %), and I: (18.20 %). Found 20 kinds of components in the waste sludge aliphatic petroleum to form a homologous series nC10-nC30, and two aromatic components, namely the 2.7-dimethyl naphthalene and 1.4-dimethyl azulene. Callyspongia sp sponge biomass concluded at the highest IV treatment degrading aliphatic hydrocarbons, then treatment III, II and I, while the aromatic components are not degraded by biomass Callyspongia sp sponge at all treatments

Study of the manufacture of biohydrogenBiohydrogen from Blotong Solid Waste and Sewer Liquid Waste by Anaerob Fermentation. Hydrogen is a clean and efficient energy source. The gas has the highest energy content per unit and is a fuel that is not chemically bonded with carbon. Hydrogen is an alternative energy source that can be produced from renewable energy sources such as biomass known as biohydrogen. Biohydrogen production can be done by fermentation technique. This method is a combination of chemical and biological approaches. Biological waste that became the raw material for the manufacture of hydrocarbons is degraded using various types of fungi. While chemically using strong acids from a strong start to a diluted. The specialty that exists in biohydrogen is that biohydrogen is easily converted to fuel or electricity without leaving pollutants. This research was conducted with the aim to utilize the industrial waste of sugar by using anaerobic fermentation hydrogenation bacteria to produce biohydrogen as renewable and environmentally friendly fuel and can identify good ratio to produce biohidrogen between solid waste with liquid waste. This research was conducted with 3 comparasion of variation between solid blotongwaste and sugar industry liquid waste that is: 1:1, 1:2, 2:1. From the results of this study it is concluded that the best ratio of the ratio of biohydrogen is the ratio ratio 2:1 which identifies the formation of visible gas in the balloon.

Heterogeneous hydrogels with desired matrix complexity are studied for a variety of biomimetic materials. Despite the range of such microstructured materials described, few methods permit independent control over microstructure and microscale mechanics by precisely controlled, single-step processing methods. Here, a phototriggered crosslinking methodology that traps microstructures in liquid-liquid phase-separated solutions of a highly elastomeric resilin-like polypeptide (RLP) and poly(ethylene glycol) (PEG) is reported. RLP-rich domains of various diameters can be trapped in a PEG continuous phase, with the kinetics of domain maturation dependent on the degree of acrylation. The chemical composition of both hydrogel phases over time is assessed via in situ hyperspectral coherent Raman microscopy, with equilibrium concentrations consistent with the compositions derived from NMR-measured coexistence curves. Atomic force microscopy reveals that the local mechanical properties of the two phases evolve over time, even as the bulk modulus of the material remains constant, showing that the strategy permits control of mechanical properties on micrometer length scales, of relevance in generating mechanically robust materials for a range of applications. As one example, the successful encapsulation, localization, and survival of primary cells are demonstrated and suggest the potential application of phase-separated RLP-PEG hydrogels in regenerative medicine applications.

Incorporation of recycled fibres in high value paper products can reduce cost and environmental loads. Papermaking potential of cellulosic fibres decreases with recycling. The phenomenon of fibre hornification during pressing and drying is normally held responsible for the loss in strength. To study the impacts of recycling on pulp, fibre and paper properties some non conventional characterisation techniques like fibre saturation point, X-rays microtomography, environmental scanning electron microscopic observations, atomic forcemicroscope (PeakForce QNM mode) and inverse size exclusion chromatography(ISEC) were used. In order to achieve good reproducibility of ISEC measurements,a semi-automatic column fabrication pilot system was built. The techniques were first validated on refining process before being applied to the recycling process. In this study, it was found that fibre hornification alone cannot fully explain loss in strength during recycling. The loss in strength is much more complex and it is required to understand the morphological and ultrastructural changes associated with recycling. Fibre width, cell wall thickness,curl, kink, irregularities decreased during recycling. Fibre became hard and brittle in dry state. Number of weak points in the fibre wall were increased initially and in the later recyclings. The increase in wet breaking length indicates increased surface friction and capillary forces with recycling. Decrease in bonded area during first recycle may be caused by the loss of fines and fibre flexibility whereas the increase afterwards may be linked to the lumen collapse.The strength of fibres did not decrease with recycling as shown by zero-span breaking lengths therefore the quality of bond may be deteriorated. It was thought that the partially delaminated P/S1 layers may be responsible for the loss of paper strength. It is suggested since the significant change is associated with the pressing and drying of never dried pulp therefore the drying process needs to be revisited. The delaminated layer should be restored so as to increase the recyclability of the recovered fibres for high value paper. Influence of recycled pulp blends on physical properties of paper was also studied. It was revealed that small quantity of recycled pulp can be used without significantly affecting the mechanical strength properties.

Coal is a fossil fuel that can be used as an alternative fuel source fuel oil and natural gas that had been reduced. Coal reserves in Indonesia, especially in Sulawesi potent enough, but until now have not been utilized as fuel in view of the content of sulfur is relatively high which may cause damage to the appliance combustion, and can cause environmental pollution, except first performed desulfurization process prior to combustion (precombustion ). This study aims to reduce the sulfur content of pyrite in the coal so that it meets the criteria to be used as one of the fuel industry. Specifically, this research aims to study the mechanisms and kinetics of coal using an oxidizing ferry depiritsasi sulfate, in an effort to minimize the sulfur content of the coal, the Coal Desulfurization Using research conducted oxidizing iron (III) Processed Waste Iron. Research desulfurization of coal origin Mallawa (Sulawesi) was performed in a laboratory scale reactor (four-neck flask) with a semi- batch system, equipped with a compressor, flowmeter, a thermometer and stirrer. Characterization, proximate and ultimate analysis of coal is done following the ASTM standard procedure. Total sulfur analysis was conducted using esckha combined with UV spectrophotometer, while the calorific value of coal was measured by a bomb calorimeter. From the results obtained value per count of the reaction order n = 1,771. This value was not unanimous but a fraction indicating that the reaction reagent depiritisasi with iron (III) sulfate is a complex reaction that consists of several stages of reaction. The results of this study the kinetics equation obtained by reacting coal depiritisasi iron (III) sulphate at a temperature of 90 ° C, stirring speed of 930 rpm as follows: - rS = 6,741.10-2.CS (1,771)

Some species of freshwater fish living in Lake Village Antang of Balang Tonjong, Mangala, is one source of food small percentage people of Makassar. The Balang Tonjong lake located on the eastern part the city of Makassar, including densely populated residential areas and approximately 60% of the circumference of the lake is an access road suitable for vehicles with high density. These two things are very possible the exposure to heavy metals, especially lead (Pb). Pb contamination assessment to fish, water and sediment of the lake is important, aims to provide information to the community about safety source of food fish. The method used is AAS with destruction phases, extraction and measurement of absorption at λmaks. 238, 3 nm. Extracting solution of HCl pa: HNO3 pa ratio of 3: 1. The results of the analysis of Pb contamination levels on Lake Balang Tonjong for the five types of fish samples in a row, the catfish (1.1917 mg/Kg); Tilapia Black (0.7214 mg/Kg); Sepat fish (0.8239 mg/Kg); Betok fish (0.9095 mg/Kg) and eel (1.0057 mg/Kg). While the content of Pb in water and sediments of Lake Balang Tonjong respectively 0.4998 mg/L and 23.2665 mg/Kg. The Balang Tonjong lake water unfit as a secondary source of water and sediment meet the requirements of the value of maximum limit according to NSI No. 7758 in 2013 to the lake water 0.15 mg/L and sediment ≥35 mg/Kg

For mobile applications, the rapid heating rates and the high operating temperatures of solid oxide fuel cells (SOFCs) lead to increased stress on the joining and sealing points of the material components used for the development of planar SOFC stacks. At the junctions of the metallic components and alternatively to the currently used glass-ceramic solders the possible use of oxide ceramic as an insulation layer in combination with air braze filler metal was examined. The joining of the components in air, without the use of vacuum or inert gases, requires that the filler metal forms strong interfacial bonds with both the ceramic (insulating layer) and the additional sheet (ferritic steel). In addition, it should be resistant to oxidation at the high operating temperatures and its thermal expansion coefficient should match those of the materials to be joined. When ceramic and metal are joined, the presence of a ductile interfacial phase compensates the differences in the thermal expansion coefficients of the phases involved. Also, it is necessary for the mechanical stability of the bond, that the binding partners are well wetted by the interfacial phase. Both Ag and Cu provide high mechanical strength, ductility, and thermal, as well as electrical conductivity. Although Ag is more expensive than Cu, it is preferred as a basis metal due to the lower process temperature and the lower oxygen affinity. A problem in using pure Ag is the poor wetting properties, at the liquid state, when in contact with oxide ceramic and steel. The high values of the contact angle (θ>120o) measured in oxide ceramic/Ag systems at oxygen concentrations of 0-3 ppm is reduced in air, but overall, the systems remain non-wetting (θ>90°). Good wetting (θ<

Approximately 75% of new molecular entities approved by the Food and Drug Administration (FDA) for use in the pharmaceutical industry are found to have poor aqueous solubility. This undesirable attribute leads to consequences such as higher doses required to reach therapeutic levels, greater vulnerability to food effects, lesser fraction absorbed in the small intestine and damage to the environment due to increased quantity of excretion. The addition of an excipient (i.e. a FDA approved inactive ingredient) to the molecular structure of an active pharmaceutical ingredient (API) through intermolecular bonding is of growing interest because the properties of the API can be tuned without further clinical testing. Crystal engineering utilizes the knowledge of intermolecular interactions to design new solids with improved properties (e.g. solubility, stability, bioavailability, dissolution rates). In this thesis, these techniques are applied to increase the solubility of three APIs with low solubility: esomeprazole magnesium, curcumin and rufinamide. Through an intense screening process, novel solid states were discovered including a water/butanol solvate of esomeprazole magnesium and a co-amorphous mixture comprised of curcumin and folic acid dihydrate. The co-amorphous mixture was found to have increased dissolution rate compared to curcumin and can be repositioned as a prenatal drug. Characterization of these products include powder and single crystal X-ray diffraction, differential scanning calorimetry, thermogravimetric analysis, Fourier Transform infrared spectroscopy, solution nuclear magnetic resonance spectroscopy and dynamic vapour sorption. Screening of rufinamide did not lead to the discovery of any new forms, but the refined molecular structure of the metastable form is reported.

Rice straw is an agricultural waste in Indonesia that can be used as animal feed. This study aimed to determine the effect of rice straw with various treatments (physical, chemical, biological and combinations) against the percentage of carcasses, slaughter weight and fat percentage of the local rams. The experiment was conducted at the Laboratory Animal Sciences Program Faculty of Agriculture, Animal Husbandry University of North Sumatra for 4 (four) months starting from March to June 2012. This research method using 20 rams with an average initial body weight range 11.16 ± 0.98 kg and 3month age range. The research method used was a completely randomized design (CRD) consisting of 4 treatments and 5 replications. The treatments used were P1 (rice straw processed physically (chopper) + concentrate), P2 (rice straw treated with the chemical (NaOH) + concentrate), P3 (straw treated with biological(Aspergillusniger)+concentrate)andP4(ricestraw+concentratesprocessedincombination). The results showed that administration of rice straw in carcass weight parameter obtained results are significantly different P> 0.05. Carcass percentage, fatty heart, kidney fat and the pelvic fat were not significantly different P> 0.05 level. Carcass weight, carcass percentage, fat percentage heart and kidney fat washighestinP3treatment, whereascarcassweightand carcasslowest percentagecontainedintheP2 treatment. The conclusion of this study is the presence of rice straw with various treatments (physical, chemical, biological and combined) in sheep feed is still a positive influence where the provision of rice strawwithvarioustreatmentsdonotreducethe weightoftheramcarcass.

5-hydroxymethylfurfural (HMF) as a versatile and polyfunctional compound derived from dehydration of biomass has attracted increasing attentions in research over the past decades. HMF is an important intermediate and platform chemical, which can be converted into different useful chemicals as well as the promising biofuels. It can be obtained from acid-catalyzed dehydration of different C6-based carbohydrates such as glucose, fructose, sucrose and cellulose. In this thesis, a cost-effective process for catalytic conversion of simple sugars (particularly glucose and fructose) and industrial grade sugar syrups to HMF was studied in a novel biphasic continuous-flow tubular reactor using inexpensive heterogeneous solid catalysts and biphasic media (aqueous/organic). Commercial and synthesized heterogeneous catalysts were used for the catalytic experiments and their activities in terms of conversion, selectivity and yield were compared. It is assumed that catalytic conversion of glucose to HMF involves two-step reaction pathway of glucose isomerization to fructose and subsequent fructose dehydration to HMF. Thus, the experimental approach for this research was to first isomerize glucose to fructose using heterogeneous solid base catalysts and then dehydrate fructose to HMF using heterogeneous solid acid catalysts. Thereafter, continuous single-step conversion of glucose and industrial grade sugar syrups derived from corn and wood to HMF was investigated. In each section, fresh catalysts were characterized comprehensively and the stability of some selected catalysts and feasibility of catalyst recycling were examined. The effects of different experimental conditions including reaction temperature, feeding flow rate, initial feedstock concentration, catalyst loading, presence of extracting organic solvent and phase transfer catalyst were also studied. At the best operating conditions, the maximum fructose yield of 25% was achieved from isomerization of glucose over magnesium oxide catalyst and maximum HMF yields of 60%, 45% and 53% were obtained from dehydration of fructose (over Amberlyst 36 catalyst), glucose (over niobium phosphate catalyst) and HFCS-90 (over niobium phosphate catalyst), respectively. The deactivation mechanism of some selected catalysts was also investigated by analysing the used catalysts and the insoluble humins produced during the reaction as the main by-product responsible for the catalyst deactivation. The kinetics of glucose dehydration reaction over niobium phosphate catalyst was also studied.

Diclofenac (DCF), a widely used non-steroidal anti-inflammatory drug (NSAID), is a commonly detected substance that readily accumulates in tissues of aquatic fish and poses a threat to wildlife and freshwater quality. Advanced Oxidation Processes (AOPs) have been explored as an alternative method for complete mineralization of DCF as conventional treatment methods are inadequate for treatment of trace contaminants. This study employs a semi-batch, swirl-flow, monolithic type photocatalytic reactor to determine intrinsic kinetic parameters of DCF mineralization, in an immobilized system under both UV and visible radiation. The goal of this work to determine true kinetics of DCF, after correcting for external mass transfer resistance that exists when catalysts is immobilized, as a function of various operating parameters such as flow rate, catalyst loading, pH, light intensity, initial concentration, and photocatalyst type. This study also utilized an innovative method of solar-activation of TiO2 using Eosin-Y dye for the degradation of DCF. Furthermore, the study incorporated a central composite design (CCD) to optimize the dye concentration and estimated the cost for the present process. Optimized parameters for light intensity (750 mW/cm2), Eosin-Y dye concentration (2 mg/L), TiO2 loading (37.5 mg/cm2) and DCF concentration (25 mg/L) were determined by means of a CCD study. A cost estimation for the materials used for the current process was also performed. It was determined that the additional cost of using 4 ppm instead of 2 ppm to achieve only 10% more DCF degradation is not warranted and would require additional treatment to remove subsequently formed halogenated compounds. In the last part of this thesis, in order to determine mechanism of degradation of DCF, intermediate products were identified. 22 different intermediate products were found during the visible light photocatalytic degradation of DCF using EY-sensitized TiO2 at the optimized conditions. Out of the 22 intermediates, 19 of the transformed products were identified. Toxicity analysis of the treated and untreated samples of DCF were also assessed. The treated samples indicated an increase in toxic effect to Daphnia magna compared to the untreated DCF solution. The objective and significant contribution of this study lies in (1) obtaining true kinetic data independent of reactor types, (2) incorporation CCD to optimize the reaction operating parameters, (3) cost estimation of the present process, and (4) identification and toxicity analysis of DCF intermediates formed during the optimized process.

Electrode materials are critical for microbial fuel cells (MFC) since they influence the construction and operational costs. This study introduces a simple and efficient electrode material in the form of palm kernel shell activated carbon (AC) obtained in tropical regions. The novel introduction of this material is also targeted at introducing an inexpensive and durable electrode material, which can be produced in rural communities to improve the viability of MFCs. The maximum voltage and power density obtained (under 1000 Ω load) using an H-shaped MFC with AC as both anode and cathode electrode material was 0.66 V and 1.74 W/m3, respectively. The power generated by AC was as high as 86% of the value obtained with the extensively used carbon paper. Scanning electron microscopy and Denaturing Gradient Gel Electrophoresis (DGGE) analysis of AC anode biofilms confirmed that electrogenic bacteria were present on the electrode surface for substrate oxidation and the formation of nanowires.

Bubble column reactors, with or without solid particles, have a number of applications in the chemical, petrochemical, biochemical and environmental industries. A number of these industrial applications require internals such as baffles, heat transfer surfaces and special distributors to meet demands. Proper selection and design of these internals can lead to the improved performance and efficiency of a bubble column reactor. Several experiments are carried out in a bubble column equipped with a concentric tube bundle (CT) and an internal combination consisting of a concentric tube bundle and concentric baffle (or static mixer) (CTB) respectively. Neutrally buoyant particles are used to determine the effect of the CT and CTB internals on the local flow structures in the equipped column respectively. More upward, near-linear particle movements are observed with the CTB internal over the CT internal. Several non-linear particle movements are also observed. Overall bulk liquid circulation flow patterns are proposed for the intermediate to high gas velocity range based on the observed local flow structures for both internals. Comparisons are made between the gas holdups obtained during internal equipment and that of a comparable hollow bubble column from the literature. Both internals increase the gas holdup of a hollow bubble column. However, the increases with the CT internal are higher by more than 25% of that obtained with the CTB internal on average. The effect of the internals on average bubble size is investigated for the small bubble class. Smaller average diameters are obtained when the CT internal is used. The interfacial area in the presence of the two internals is determined respectively. Higher interfacial areas are obtained with the CT internal. The average difference in interfacial area is 54.0 m2/m3. The effect of the internals on mixing time is determined through dye and aqueous salt tracer studies. In both instances, higher mixing times are obtained with the CTB internal. Liquid backmixing is quantified through the axial dispersion coefficients obtained from the salt tracer studies. The axial dispersion coefficients obtained with the CT internal are higher than that of the CTB internal by about 15% on average.