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This study examined the application of high-gradient magnetic separation (HGMS) for recycling of super-paramagnetic polymer adsorbent (MPA), namely, polyvinyl acetate-iminodiacetic acid. The HGMS can be incorporated with the adsorption and desorption processes (ADPs) with fresh or regenerated desorbed MPAs and exhausted adsorbed MPAs, respectively. This combines the permanent magnet’s advantage of low running costs with the easy operation using the solenoid to flush the filter in place. The effects of the inlet concentration of MPA in solution (CLF,i) and the fluid velocity (v0) or volumetric flow rate (QLF) on the performance of the recovery of MPA via HGMS were assessed. The results indicated that the separation efficiency (η or P0), breakthrough time (tB) and exhaustion time (tE) of HGMS reduce as CLF,i, as well as v0, increases. Further, the filter saturated capture capacity (σS) of HGMS also decreases with increasing v0. The effect of v0 on tB proportional to 1/v02 is more significant than that on σS proportional to 1/v0. A kinetic model of HGMS shows good agreements for the experimental and predicted breakthrough results, with determination coefficients of 0.985–0.995. The information obtained in this study is useful for the rational design and proper operation of a HGMS system for the recycling and reuse of MPA in ADPs.

This study examined the torrefaction performance of Jatropha-seed residue after mechanical screw-press extraction of oil (denoted as JME) at fixed torrefaction temperature (Tr) of 533, 553 and 573 K in the torrefaction time (tr) range of 10–60 min. The characteristics results of torrefied JME (JMET) indicated that the mass yield decreases while dry-basis high heating value (HHD) increases with increasing Tr and tr. At tr = 20 min or longer and Tr of 533–573 K, the HHD of obtained JMET is suitable for B1/B2/D Taiwan power industry fuel requirement. In addition, the H/C and O/C atomic ratios of JMET are better (i.e., lower) than those of torrefied wood and close to those of lignite and sub-bituminous coal. The satisfactory energy densification (ED) of about 1.3 can be achieved for Case 1 at higher Tr of 573 K and shorter tr of 30 min with log severity factor (logSF) of 7.37 or Case 2 at lower Tr of 553 K and longer tr of 50 min with logSF of 7.00. The results indicated that Case 2 exhibits a lower value of SF than Case 1 at the same level of satisfactory ED, which is more beneficial for the torrefaction of JME.

In this study, waste bamboo chopsticks (WBC) were upgraded as solid bio-fuel by torrefaction using a tubular furnace with nitrogen as carrier gas. In order to fulfill the quality specifications of coal and industrial wood pellets, the effects of temperature and time of torrefaction on proximate and ultimate compositions and its dry-basis heating value (H HD ) were studied and elucidated. The results showed that the mass yield of WBC is 69% at 563 K and 40 min, while H HD of WBC is increased from 19.31 to 23.04 MJ kg −1 with an energy densification factor of 1.19, which satisfy the specification of quality D of Taiwan Power Co. and I3 industrial quality of Initiative Wood Pellets Buyers. Further, the torrefied WBC (WBC T ) pellets become convenient to store, transport and processing and hard to be rotten because of the modification of surface hydrophobicity. The ash content of WBC T is only 2.19 wt.% in wet basis, which is beneficial in practical boiler. Further, the energies needed for drying, heating and torrefaction is 2.31 MJ for processing 1 kg WBC with CO 2 emission of 0.339 kg. Therefore, WBC T would be practical alternative as solid bio-fuel for cofiring with coal.

In this study, biomass of rice straw (RS) and wood (WD) and their torrefied biomass (RST and WDT) were used as solid biofuel (SBF) for co-firing individually with coal in a commercial continuous chain-grate steam boiler system, which was conducted at fixed input rate of heating value of mixture of SBF and coal and at fixed airflow rate. The effects of key system parameters on the gaseous and particulate pollutions and ash were examined. These include SBF type and blending ratio (RBL) of biomass (i.e., SBF) in the mixture of coal and biomass based on heating values for co-firing.The results indicated that wood, which possesses high heating value while less amount of ash, is more suitable for co-firing with coal than rice straw. Torrefaction can increase the heating value of biomass and homogenize its property, being beneficial to co-firing. Also, torrefaction can decompose the hydroxyl group of biomass, which makes biomass tending to possess hydrophobicity. This, in turn, helps the storage and transportation of biomass. Generally, adding the RS (with RBL = 5-10%), WD (2-15%), RST (2-10%) and WDT (2-20%), respectively, with coal decreases the emissions of NOx and SO2, but increases that of CO (except RST). The emission of HCl is little. The addition of biomass also increases the emission of fine particulate matters (PM) especially PM2.5 in the flue gases, raising PM2.5/PM100 from 34.87 to 78.35 wt.% (Case 50%WDT). These emissions for the Cases tested satisfy with Taiwanese emission standards of stationary sources which set limitations of NOx, SO2, CO and HCl < 350, 300, 2000 and 80 ppmv, while PM < 50 mg/m3, respectively. The results support the use of RS, WD, RST and WDT for co-firing with coal.Implications: This study examined the suitability of using solid bio-fuels to co-fire with coal in an industrial chain-grate steam boiler system with a capacity of 100 kW, in order to achieve carbon-free emissions. Both biomass and torrefied biomass of solid bio-fuel were tested. The findings would be useful for proper design and rational operation of solid bio-fuel/coal co-firing combustion matching the appeal of sustainable material management and circular economy of biomass, and of adaptation of global warming induced by greenhouse gases. It also provides information for policy-makers to promote the co-firing application of biomass and related bio-waste materials.

Combined heat and power production from biogas is now playing an important role in energy and resource utilization as well as pollution control in waste water treatment. This research used biogas from the Bali Sewage Treatment Plant in New Taipei City, Taiwan, as a major source of fuel for the electricity generation. A micro gas turbine electricity generator, Capstone CR-30, which possesses a maximum rated power load (PWL) of 30 kW, was equipped to convert biogas into electricity. The biogas is mainly composed of CH4 (56.1 ± 8.0 vol.%), CO2 (25.5 ± 9.8 vol.%), H2 (0.5 vol.%), and H2S (0.99 ± 0.07 ppmv). During the test operation period of the generator, it was found that the thermal efficiency increases from 19.8% to 23.4% kWhe/kWhth, while the electricity generation efficiency (ηEB) also rises from 0.93 to 1.09 kWhe/m3 biogas as the PWL increases from 10 kW to 30 kW. The results indicated that the generator has a better performance with higher PWL. At PWL = 30 kW, the average adjusted concentrations of CO and NOx (adjusted to 15 vol.% O2) emitted from the generator are 86 ppmv and 17 ppmv, respectively. Both are much lower than the emission standards of stationary sources in Taiwan of 2000 ppmv and 150 ppmv, respectively. Thus, PWL of 30 kW was selected in cooperation with biogas inflow = 0.412 m3/min and air/fuel ratio (i.e., air/biogas ratio) = 76.0 vol./vol. for the long-term regular operation. At the above setting conditions for long-term operation, the generator continuously consumed the biogas and provided stable electricity generation at a rate of 19.64 kWhe/h for a 2-year running period. Moreover, the greenhouse gas can be cut off with a rate of 10.78 kg CO2e/h when using biogas as fuel for electricity generation. Overall, this research proves that the application of a micro gas turbine electricity generator not only has promising performance for using biogas but also gives a significant reduction of greenhouse gas emission, which fits the concepts of the circular economy and environmental protection.

Considering coordination effects, this study prepared a photocatalyst with a highly visible light respondence using co-doped titania with non-metal (nitrogen and sulfur) and lanthanide metal ions (cerium). As well, the photoelectrochemical characteristics and photocatalytic effects were tested. The feasibility was investigated on the power of the photoelectrochemical solar cell and the photodegradation of volatile organic compounds (VOCs) from indoor air pollution, taking toluene as a model compound. In this study, the different intensities of a light-emitting diode (LED) and the different initial concentrations (10–50 ppmv) were examined, and the kinetic model was addressed. The maximum power (Pm) at white light emitting diode (WLED) was 35.5 and 174.68 times that of the solar cell without cerium doping and without Ce, N and S doping, respectively. The decomposition efficiency (ηD) was more than 99.9% below 30 ppmv at 5050 WLED with 10 Ce/TiNxSyO2−x−y (10 Ce/TNST). The photocatalytic decomposition was elucidated according to the Langmuir-Hinshelwood model. The reaction rate constant (k) and adsorption equilibrium constant (KL) of 10 Ce/TNST with 5050 WLED in the range of 10–50 ppmv were 0.2637 ppmv min−1 and 0.7008 ppmv−1, respectively. This study succeeded in predicting optimum photodegradation conditions from the PECSC test. The photocurrent and power from the co-doped photocatalysts are related to the photodegradation efficiency.

The catalytic oxidation of 1,2-dichloroethane (DCEA) using Pt/Al2O3 with and without ozone (noted as OZCO and COXI, respectively) was carried considering the key operation parameters of reaction temperature (T), space velocity (SV) of catalyst and inlet concentration of O3 ( C O 3 ). The results indicate that OZCO decreases the reaction temperature and enhances the conversion of DCEA (X) to form CO2, HCl and Cl2 comparing with COXI. At 200 ppmv C O 3 and 125,000 1/h SV, 50% and 90% conversions of DCEA via OZCO are achieved at 430 and 610 K, while those via COXI are reached at 582 or 640 K, respectively. The mineralization of carbon in DCEA to form CO2 ( Y C O 2 ) with ozone (e.g. 90% at 620 K) is systematically higher than that without ozone (e.g. 60% at 620 K). The conversions of chlorine atom in DCEA to Cl in HCl and Cl2 are about 62.5% and 37% for OZCO at 625 K with ∼100% Y C O 2 , which are higher than 51.5% and 10.3% for COXI at 645 K with 97% Y C O 2 , respectively. Thus the conversions of carbon and chlorine are near completion, indicating the effectiveness of OZCO for destructing the chlorine-containing pollutant of DCEA.

In this study, vinyl chloride (VC), the primary material for manufacturing polyvinyl chloride (PVC), is decomposed via catalytic oxidation (C-OX) using Pt/γ-Al2O3 catalyst. The effects of related major factors such as reaction temperature (T) and gas hourly space velocity on the conversion of VC (X) were examined. The values of T for achieving conversions of 50% and 90% are 504 and 580 K with C-OX, respectively, whereas those without Pt/γ-Al2O3 (i.e., thermal oxidation, T-OX) are 900 and 983 K, respectively, thus indicating that C-OX significantly reduces T for effective oxidation of VC to form CO2, HCl, and Cl2 when compared with T-OX. The mineralizations of carbon in VC to form CO2 are 75.5% and 38% for C-OX and T-OX, respectively, at 90% X. The conversions of chlorine atom in 1,2-dichloroenane (DCEA) to Cl in HCl and Cl2 are approximately 42% and 50.8% for C-OX and T-OX, respectively, at 90% X. These results indicate that the Pt/γ-Al2O3 catalyst exhibits remarkable performance for the mineralizations to form CO2 even though a proportion of chlorine atoms are adsorbed on the Pt surface. The Eley-Rideal model can be used to describe the experimental results, thus yielding activation energy and frequency factor values of 49.0 kJ mol(-1) and 1.77 × 10(6) s(-1), respectively. The obtained information and kinetic parameters are useful for the rational design and operation of C-OX process for the abatement of VC.

Although the main purpose of the torrefaction of biomass is to produce high quality solid bio-fuel, the by-products, including liquid and gas products, are worth investigating to know their effects on the environment and the reusable possibility. Consequently, after torrefying waste bamboo chopsticks (WBCs) for producing solid bio-fuel, the liquid and gas products were examined in this study. The torrefaction target was set to produce torrefied waste bamboo chopsticks (WBCT) retaining about 70 wt %. A proper torrefaction temperature (Tr) and torrefaction time (tr) were found at 563 K and 40 min, respectively, for carrying out the torrefaction in a tubular furnace with carrier nitrogen. These conditions gave a solid yield (YS) of 69 wt % of WBCT relative to the original WBC, and 31 wt % of by-products were produced. The liquid products were composed of water as high as 62 wt %, along with some organic acids. Some medicine components were also found in the liquid products, representing potential medicine applications. During torrefaction, CO, NOx, SO2, and CO2 emissions were largely discharged from 10 to 20 min of torrefaction time. O2, CO2, and H2O are the major compounds in the total gas products collected. Some combustible gases of C1 to C6 hydrocarbons were also produced. Moreover, the gas volume balances were computed and evaluated. The information obtained in this study is useful for the proper design, operation, pollution control, and utilization of the products.

The purpose of this study is to co-sinter washed-fly ash, limestone sludge, stone sludge, and iron-oxide sludge to fabricate 4 types of eco-cement clinkers. The compound raw materials were burned for 2 h at 1400°C to form the eco-cement clinkers, all of which met the toxicity characteristic leaching procedure requirements. The results show that the major components of ordinary Portland cement (OPC), C3S, C2S, C3A, and C4AF, were present in the eco-cement clinkers. The compressive strength development indicated that the EcoA pastes were similar to those of commercial OPC products. The compressive strength in the EcoG pastes decreased because of the amount the α-C2S increased. The mercury intrusion porosimetry results showed that the pore volume in the pastes gradually decreased when the curing time increased. Additionally, from the X-ray diffraction results, all the eco-cements produced Ca(OH)2 during hydration, which also increased with curing age. The scanning electron microscopy images of OPC and EcoA pastes showed that the pore volume decreased and the denser structural increased with the curing time increased. In addition, adding higher amounts of 1% washed-fly ash caused to increase the content of α-C2S. The result show that this co-sintered process from 1% washed-fly ash and 99% waste sludge (77% limestone sludge, 19.51% stone sludge and 2.49% iron-oxide sludge) to produce eco-cement with excellent mechanical characteristics. © 2014 American Institute of Chemical Engineers Environ Prog, 34: 964–972, 2015

This study uses different scenarios to evaluate, by means of energy life-cycle assessments (ELCAs), the energy balance of potential gasification technology and limitation boundaries in Taiwan. Rice straw is chosen as the target material in this study because it is the most significant agriculture waste in Taiwan. Energy products include syngas (CO + H2), methane, carbon dioxide and carbon black residue. The scenarios simulate capacities of 50,000–200,000 tons/year. The distances of collection and transportation are calculated by a circular area 50–100 km in diameter. Also, the on-site and off-site pretreatments of rice straw are evaluated. For this optimum scenario case, the average of the total input energy for the assessed systems is about 15.9% of the average output energy; the value of the net energy balance (NEB) is 0.841. Every technological process has positive energy benefits at all on-site scenario cases. As the capacity is increased, the energy consumption required for transportation increases and the values of the energy indicators decrease. According to the limitation boundaries from the tendency model at on-site cases, the suggested transportation distance and treatment capacity are below 114.72 km and 251,533 tons/year, respectively, while the energy return on investment (EROI) value is greater than 1.

Auto-induced temperature-rise effects of ultrasonic irradiation (UI) on the esterification performance of jatropha oil (JO) were studied. Comparisons with other methods of mechanical mixing (MM) and hand shaking mixing were made. Major system parameters examined include: esterification time (tE), settling time (tS) after esterification and temperature. Properties of acid value (AV), iodine value (IV), kinematic viscosity (KV) and density of JO and ester product were measured. The esterification conversion efficiencies (h) were determined and assessed. Sulfuric acid was used to catalyze the esterification using methyl alcohol. For esterification without temperature control, h at tE ¼ 10 and 30 min for UI of 56.73 and 83.23% are much higher than those for MM of 36.76 and 42.48%, respectively. At tE ¼ 10 min, the jatropha oil esters produced via UI and MM respectively possess AV of 15.82 and 23.12 mg KOH/g, IV of 111.49 and 113.22 g I2/100 g, KV of 22.41 and 22.51 mm 2 /s and density of 913.8 and 913.58 kg/m 3 , showing that UI is much better than MM in enhancing the reduction of AV. The tE exhibits more vigorous effect on AV for UI than MM. The UI offers auto-induced temperature-rise, improving the mixing and esterification extents.

The aim of this work is to study the feasibility and operational performance of plasmatron (plasma torch) gasification of municipal solid waste mixed with raw wood (MSW/RW) derived from the pretreatment of Steam Mechanical Heat Treatment (SMHT), as the target material (MRM). A 10 kW plasmatron reactor is used for gasification of the MRM. The production of syngas (CO and H 2 ) is the major component, and almost 90% of the gaseous products appear in 2 min of reaction time, with relatively high reaction rates. The syngas yield is between 88.59 and 91.84 vol%, and the recovery mass ratio of syngas from MRM is 45.19 down to 27.18 wt% with and without steam with the energy yields of 59.07–111.89%. The concentrations of gaseous products from the continuous feeding of 200 g/h are stable and higher than the average concentrations of the batch feeding of 10 g. The residue from the plasmatron gasification with steam is between 0 and 4.52 wt%, with the inorganic components converted into non-leachable vitrified lava, which is non-hazardous. The steam methane reforming reaction, hydrogasification reaction and Boudouard reaction all contribute to the increase in the syngas yield. It is proved that MSW can be completely converted into bioenergy using SMHT, followed by plasmatron gasification.

A radio-frequency-powered atmospheric pressure plasma jet (APPJ) was produced in ambient air assisted by Ar carried gas for the decomposition of binary mixture of naphthalene (Nap) and n-butanol without and with Pt/Al2O3 catalyst. The mixed feed gas streams of Nap/n-butanol were used to simulate the background of vapor released from the source solution of Nap, such as gasoline and some industrial flue gases. The effects of some major system parameters such as input power, plasma energy density ( E ¯ ) and space velocity (SV) of catalyst on the plateau temperature (TP) of reactor and conversions of Nap (XNap) and n-butanol (Xn-b) were studied and elucidated. The results show that the effectiveness of the catalytic APPJ (CAPPJ) is evident as indicated by the increase of XNap and Xn-b and the rate constant. At E ¯ = 3.75 kJ/L without catalyst, the values of XNap and Xn-b are 30 and 19%, respectively. In the presence of Pt/Al2O3 catalyst with SV = 17,400 1/h, XNap and Xn-b can reach as high as 99%. Note that the values of TP were 580 and 480 K without and with Pt/Al2O3 catalyst at SV = 17,400 1/h and E ¯ = 3.75 kJ/L . The proposed kinetic models describe the relationships of XNap and Xn-b with the major parameters and reaction order of −1.5 and 1 for the APPJ and CAPPJ degradation of binary mixture of Nap and n-butanol, respectively, showing good agreement with the experimental data. The information obtained is useful for operation, design, and analysis of plasma devices.

The autoclaving combined with mechanical separation, known as the mechanical heat treatment, is one of the promising alternatives to treat the mixed wastes consisting of organics and inorganics. After autoclaving, the organics can then be sorted, separated and recovered for the re-utilization. In this study, the steam autoclaving of bamboo chopstick (BC), which is one of the major biomasses in the municipal solid waste, was performed. The effects of steam autoclaving temperature (T) and autoclaving reaction time (t) on the characteristics of BC were examined. The thermal gravimetric and differential thermo-gravimetric analyses were conducted to assess the pyrolysis behavior of autoclaved BC which can be further treated to produce up-graded refuse derived fuel or bio-char. The results indicated that the autoclaving extent of BC (=(initial mass − mass at t)/initial mass, in dry basis) increases with increasing T and t. The high heating value per mass in dry basis (HHMD) of raw BC after autoclaving increases from 4365 kcal/kg to about 4975 kcal/kg at T = 428 K with t = 60 min (A428-60) and to 5044–5158 kcal/kg at 453 K with 30 (A453-30) and 60 min (A453-60), enhancing the energy densification ratio (ratio of HHMD after to that before autoclaving) to 1.06–1.17. However, on the wet basis, the water content of autoclaved product for the case of A428-60 is 35.85 wt.% being less than those of A453-30 and A453-60 of 45.33–55.20 wt.%. The comparison indicated that the conditions at 428 K with 60 min are more appropriate than the others, giving satisfactory HHMD with less water content. The pyrolysis behaviors of autoclaved BCs employing T = 428–453 K and t = 15–60 min are closed to that of raw BC, thus retaining the pyrolytic quality of BC. The information obtained in the present study is useful for the rational design and proper operation of autoclaving system for treating the wasted BC.

This investigation examines the chemical and physical behaviors of waste catalyst (WC), a byproduct of the petroleum refining industry, used as a component of cement-based materials. WC was recycled as a pozzolanic material partially to replace cement to enhance the pozzolanic activity of pastes contained WC. Fourier transformation infrared spectroscopy (FTIR), differential thermal and thermogravimetric analysis (DTA/TGA) and 29Si magnetic angle spinning/nuclear magnetic resonance (29Si MAS/NMR) approaches were adopted to relate both the hydration products of pastes contained WC and the structural features to its cementitious activity. The cementitious activity of WC was evaluated by testing the compressive strength of blended cement pastes. The results demonstrate that the blended cements that contained 10% WC exhibited favorable cementitious activity owing to the formation of C-S-H C-A-H and C-A-S-H materials in the hydration products, and an increase in densification. The substitution of cement by WC would have an additional positive environmental impact because it would permit the recycling of a byproduct of the refinery industry in Taiwan that otherwise would remain in the environment as a waste product. © 2013 American Institute of Chemical Engineers Environ Prog, 33: 353–358, 2014

This study deals with the effect of solar panel waste glass on fired clay bricks. Brick samples were heated to temperatures which varied from 700-1000 degrees C for 6 h, with a heating rate of 10 degrees C min(-1). The material properties of the resultant material were then determined, including speciation variation, loss on ignition, shrinkage, bulk density, 24-h absorption rate, compressive strength and salt crystallization. The results indicate that increasing the amount of solar panel waste glass resulted in a decrease in the water absorption rate and an increase in the compressive strength of the solar panel waste glass bricks. The 24-h absorption rate and compressive strength of the solar panel waste glass brick made from samples containing 30% solar panel waste glass sintered at 1000 degrees C all met the Chinese National Standard (CNS) building requirements for first-class brick (compressive strengths and water absorption of the bricks were 300 kg cm(-2) and 10% of the brick, respectively). The addition of solar panel waste glass to the mixture reduced the degree of firing shrinkage. The salt crystallization test and wet-dry tests showed that the addition of solar panel waste glass had highly beneficial effects in that it increased the durability of the bricks. This indicates that solar panel waste glass is indeed suitable for the partial replacement of clay in bricks.

This study used thermal cracking with hydrogen (HTC) to produce bio-fuel oil (BFO) from jatropha oil (JO) and to improve its quality. We conducted HTC with different hydrogen pressures (PH2; 0–2.07 MPa or 0–300 psig), retention times (tr; 40–780 min), and set temperatures (TC; 623–683 K). By applying HTC, the oil molecules can be hydrogenated and broken down into smaller molecules. The acid value (AV), iodine value, kinematic viscosity (KV), density, and heating value (HV) of the BFO produced were measured and compared with the prevailing standards for oil to assess its suitability as a substitute for fossil fuels or biofuels. The results indicate that an increase in PH2 tends to increase the AV and KV while decreasing the HV of the BFO. The BFO yield (YBFO) increases with PH2 and tr. The above properties decrease with increasing TC. Upon HTC at 0.69 MPa (100 psig) H2 pressure, 60 min time, and 683 K temperature, the YBFO was found to be 86 wt%. The resulting BFO possesses simulated distillation characteristics superior to those of boat oil and heavy oil while being similar to those of diesel oil. The BFO contains 15.48% light naphtha, 35.73% heavy naphtha, 21.79% light gas oil, and 27% heavy gas oil and vacuum residue. These constituents can be further refined to produce gasoline, diesel, lubricants, and other fuel products.

Effects of modification of molybdenum carbides (β-Mo2C) catalyst using potassium (K) and vanadium (V) on the production of alcohols (AOHs) and alkanes from the hydrogenation of CO were studied. Both K and V promoters show the effectiveness on the conversion of CO (XCO), alcohol specific production rate (SPRAOH, g/h/g-catal), and alcohol selectivities (SAOH). At the K/Mo weight ratio of 0.52, the contributions of XCO and yield of alcohol (YAOH) are as high as 28.78% (in C%) and 18.14% (in C%), respectively. At the V/Mo weight ratio of 0.049, the XCO and YAOH are 26.17 and 12.01%, respectively. The corresponding XCO and YAOH for the case using β-Mo2C are 21.54% and 6.59%, respectively. The comparison indicates that both K and V are promoters for enhancing the XCO and YAOH, with K exhibiting more vigorous effect. The V–K co-modified β-Mo2C catalyst with V/K/Mo = 0.1/1/2 gives XCO of 35.05% and YAOH of 25.41% with selectivity of ethanol (SEtOH) as high as 39.88% (in C%). The results reveal the synergistic enhancement of K and V on the XCO and YAOH, especially on the SEtOH. The presence of water induces the water-gas shift reaction (WGS) of CO which further contributes the formation of reactive radicals, thus enhancing the yields of alcohols. The XCO and YAOH can reach as high as 35.74% and 26.79%. The SEtOH may be retained at satisfactory value of 35.79%. Some ethanols are converted to higher alcohols of propanol and butanol due to the presence of H2O which contains H and O. The deviation of methanol (MeOH) from the linear Anderson–Schulz–Flory (ASF) distribution for the cases using K–Mo2C, V–Mo2C and V–K–Mo2C catalysts indicates that the reaction mechanisms of the chain-propagation of alcohols are different from those using sole β-Mo2C. This may be due to the functions of V or/and K on the mechanisms, such as the insertion and re-adsorption. For the alkanes, the ASF distributions are linear for the un-modified and modified β-Mo2C catalysts, revealing that reaction mechanisms of alkanes are not altered by the K and V added on the catalysts.

By 2013 the demand for thin-film transistor liquid-crystal display (TFT-LCD) panels will be approximately 364 million m 2 , or approximately 9.8 × 10 6 ton. According to the Waste Electrical and Electronic Equipment directive, electrical and electronic equipment waste must be reused and recycled to reduce the amount of e-waste deposited in landfills. TFT-LCD waste glass comprises mainly SiO 2 and Al 2 O 3 and can be used to produce geopolymers. This study investigates the effects of the solid/liquid and SiO 2 /Na 2 O ratios on the properties of metakaolin-based geopolymers. Recycled TFT-LCD waste glass (0–40%) replaces metakaolin, thereby reducing the amount of metakaolin produced. This study tests samples to determine their quality, including setting time and compressive strength. These tests include mercury intrusion porosimetry, Fourier transform infrared spectroscopy, and scanning electron microscopy. Results indicate that TFT-LCD waste glass consists of SiO 2 and Al 2 O 3 . The geopolymer based on 10% waste glass and 90% metakaolin had a compressive strength of 62 MPa after 60 days of curing. The geopolymerization products filled the pores, producing a denser structure. TFT-LCD waste glass has the potential to partially replace metakaolin as a geopolymer material because of its useful mechanical characteristics.

Effects of reaction conditions on the production of alcohols (AOHs) and alkanes (Alk) from CO and H2, which can be obtained from the gasification of biomass, using a molybdenum sulfide (MoS2)-based catalyst of MoS2/γ-Al2O3 were studied. A high-pressure fixed packed bed (HPFPB) was employed to carry out the reaction. The results indicate that the conversion of CO (XCO) and specific production rates of alcohol (SPRAOH) and alkane (SPRAlk) are highly depended on temperature (T). In T = 423–573 K, maximum yield of alcohols (YAOH) and SPRAOH occur at T = 523 K. In the meantime, well performance gives the selectivity of ethanol (SEtOH) of 52.0 C%. For the studies on varying H2/CO mole ratio (MH/C) from 1 to 4 at 523 K, the appropriate MH/C to produce EtOH is 2, giving higher ratios of SPRAOH/SPRAlk and YAOH/YAlk than those with other MH/C. As for varying the total gas flow rates (QG) of 300, 450, 600 to 900 cm3 min−1 tested at T = 523 K and MH/C = 2, the lower QG provides longer reaction time (or gaseous retention time, tR) thus offering higher XCO, however lower productivity. For setting pressure (PST) = 225–540 psi, a supply of higher pressure is equivalent to providing a larger amount of reactants into the reaction system, this thus suggests the use of higher PST should give both higher XCO and productivity. The assessment of the above results indicates that the MoS2/γ-Al2O3 catalyst favors the production of alcohols over alkanes, especially for ethanol. The information obtained is useful for the proper utilization of biomass derived gases of CO and H2.

Effects of reaction conditions on the production of alcohols (AOH s ) and alkanes (Alk) from CO and H 2 , which can be obtained from the gasification of biomass, using a molybdenum sulfide (MoS 2 )-based catalyst of MoS 2 /γ-Al 2 O 3 were studied. A high-pressure fixed packed bed (HPFPB) was employed to carry out the reaction. The results indicate that the conversion of CO (X CO ) and specific production rates of alcohol (SPR AOH ) and alkane (SPR Alk ) are highly depended on temperature (T). In T = 423–573 K, maximum yield of alcohols (Y AOH ) and SPR AOH occur at T = 523 K. In the meantime, well performance gives the selectivity of ethanol (S EtOH ) of 52.0 C%. For the studies on varying H 2 /CO mole ratio (M H/C ) from 1 to 4 at 523 K, the appropriate M H/C to produce EtOH is 2, giving higher ratios of SPR AOH /SPR Alk and Y AOH /Y Alk than those with other M H/C . As for varying the total gas flow rates (Q G ) of 300, 450, 600 to 900 cm 3 min −1 tested at T = 523 K and M H/C = 2, the lower QG provides longer reaction time (or gaseous retention time, t R ) thus offering higher X CO , however lower productivity. For setting pressure (P ST ) = 225–540 psi, a supply of higher pressure is equivalent to providing a larger amount of reactants into the reaction system, this thus suggests the use of higher P ST should give both higher X CO and productivity. The assessment of the above results indicates that the MoS 2 /γ-Al 2 O 3 catalyst favors the production of alcohols over alkanes, especially for ethanol. The information obtained is useful for the proper utilization of biomass derived gases of CO and H2.

Blends of biodiesels produced from soapnut oil and high-oleic free fatty acids (FFAs), which are potential non-edible oil feedstocks, were investigated with respect to their fuel properties. The soapnut oil methyl esters (SNME) had satisfactory fuel properties with the exception of its high cold filter plugging point. In contrast, the biodiesel from the FFAs had favorable fuel properties such as a low cold filter plugging point of −6 °C; however, it exhibits poor oxidation stability with an induction period (IP) of 0.2 h. The complementary blend of the SNME and the FFA-based biodiesel at various weight ratios was studied to improve the fuel properties. As a result, the biodiesel blend at a weight ratio of 70:30 can successfully meet all the biodiesel specifications, except the marginal oxidation stability. Furthermore, the effectiveness of N,N’-di-sec-butyl-p-phenylenediamine at the concentration between 100 and 500 ppm on the improvement in the oxidation stability of the biodiesel blend was examined. The relationship between the IP values associated with the consumption of antioxidants in the biodiesel blends was described by first-order reaction rate kinetics. In addition, the natural logarithm of IP (ln IP) at various concentrations of antioxidant presented a linear relation with the test temperature. The IP at ambient temperature can be predicted based on the extrapolation of the temperature dependence relation.

This study examined the effects of additives of potassium carbonate (K2CO3) and zinc oxide (ZnO) on the pyrolysis of waste sunflower-oil cake using a 60 kW pilot-scale plasma torch reactor. The major gaseous products were CO and H2. The productions of CO and CH4 increased while that of H2 decreased with the addition of K2CO3. The use of ZnO reduced while enhanced the formation of CO and H2, respectively. In order to match the appeal of resource reutilization, one can use the waste K2CO3 resulted from the sorption of CO2 with KOH in greenhouse gas control and the waste ZnO obtained from the melting process as additives for the co-pyrolysis of sunflower-oil cake, yielding fuels rich in CO and H2, respectively.

The goal of this study focused on determining the optimal substituting percentage for producing cement from recycled waste foundry sand (including shell molding sand and sodium silicate sand). Raw materials that were used in preparing the pre-determined recipes were heated to 1,400°C for 6 h during the clinkerization process. Resultant clinkers were mixed with limestone to prepare the four types of cement (referred to as FEC-I, FEC-II, FEC-III, and FEC-IV). Proposed results were compared with those of ASTM type I ordinary Portland cement (OPC). Results demonstrate that the major components of OPC, including C3S, C2S, C3A, and C4AF, were present in all clinkers. Compressive strength of the FEC pastes cured for 28 days was higher than that of the OPC paste. However, the compressive strengths with curing time between 28 and 90 days increased negligibly. X-ray diffraction analyses of the hydrates of the OPC and the FEC pastes revealed that they comprised Ca(OH)2 and C-S-H gels. Signals in the 29Si ma...

The feasibility of biodiesel production from jatropha (Jatropha curcas) oil was investigated with respect to the biodiesel blending properties and its oxidation stability with antioxidants. The JME (jatropha oil methyl esters) had the cetane number of 54, cold filter plugging point of -2 degrees C, density of 881 kg/m(3) at 15 degrees C, ester content of 99.4 wt.%, iodine value of 96.55 g I-2/100 g, kinematic viscosity of 4.33 mm(2)/s at 40 degrees C, and oxidation stability of 3.86 h. Furthermore, the JME was blended with palm oil biodiesel and soybean oil biodiesel at various weight ratios and evaluated for fuel properties as compared to the relevant specifications. In addition, several antioxidants at concentrations between 100 and 1000 ppm were studied for their potential to improve the oxidation stability of the JME. The relationship between the IP (induction period) in the measurement of the oxidation stability associated with the antioxidant consumption in the JME was described by first-order reaction rate kinetics. Moreover, the In IP (natural logarithm of the IP) at various concentrations of pyrogallol showed a linear relationship with the test temperature. The oxidation stability at ambient temperatures was predicted on the basis of an extrapolation of the temperature-dependent relationship. (C) 2011 Elsevier Ltd. All rights reserved.

To be a viable alternative, a biofuel should provide a net energy gain and be capable of being produced in large quantities without reducing food supplies. Amounts of agricultural waste are produced and require treatment, with rice straw contributing the greatest source of such potential bio-fuel in Taiwan. Through life-cycle accounting, several energy indicators and four potential gasification technologies (PGT) were evaluated. The input energy steps for the energy life cycle assessment (ELCA) include collection, generator, torrefaction, crushing, briquetting, transportation, energy production, condensation, air pollution control and distribution of biofuels to the point of end use. Every PGT has a positive energy benefit. The input of energy required for the transportation and pre-treatment are major steps in the ELCA. On-site briquetting of refused-derived fuel (RDF) provides an alternative means of reducing transportation energy requirements. Bio-energy sources, such as waste rice straw, provide an ideal material for the bio-fuel plant.

This study investigates the application of a radio-frequency-powered plasma with a Pt/γ-Al2O3 catalyst to decompose the chlorinated volatile organic compound of vinyl chloride (VC) in air. The use of an atmospheric-pressure plasma jet is explored as an innovative technology for the treatment of VC. The effects of some major system parameters such as input power (PWI), plasma energy density, initial concentration of VC (C0), and space velocity (SV) of the catalyst on the plateau temperature (TP) of a reactor and conversions of VC (XVC) are studied and elucidated. The results show that the effectiveness of the plasma-assisted catalysis is evident as indicated by the increase of XVC and the rate constant. At a PWI of 250 W without a catalyst, the values of XVC were 14% and 5.4% for C0 = 200 and 450 ppmv, respectively. In the presence of the Pt/γ-Al2O3 catalyst with an SV of 17 400 h-1, the values of XVC for C0 = 200 and 450 ppmv increased to 49% and 39%, respectively. Note that the values of TP were 550 K and 430 K without and with the Pt/γ-Al2O3 catalyst at an SV of 17 400 h-1 and a PWI of 250 W. The proposed kinetic models describe the relationships of C/C0 with the major parameters for the plasma and plasma-assisted catalytic degradation of VC, showing good agreement with the experimental data. The information obtained is useful for the operation, design, and analysis of plasma devices.

TiO2 nanoparticles, doped with different Pt contents, were prepared by a modified photodeposition method using Degussa P-25 TiO2, H2PtCl6 6H2O and methanol as the solvents. The physicochemical properties of Pt/TiO2 were investigated by the nitrogen adsorption and desorption isotherm measurement technique, X-ray diffraction analysis and photoluminescence spectra, respectively. Reaction rates from photocatalytic removal of dichloromethane over Degussa P-25 TiO2 and Pt/TiO2 were evaluated. The average diameter and BET surface area of the TiO2 catalyst particles were 300 nm and 50 m2/g, respectively. The degradation efficiency was 99.0%, 82.7%, 55.2%, and 57.9% with TiO2 at inlet concentrations of 50, 100, 200, and 300 ppm, respectively. And the degradation efficiency was 99.3%, 79.7%, 76.5%, and 73.4% with a 0.005 wt.% Pt/TiO2 at inlet concentrations of 50, 100, 200, and 300 ppm, respectively. In addition, we found that the photoluminescence emission peak intensities decreased with increases in the doping amount of Pt, which indicates that the irradiative recombination was weakened. Furthermore, the results showed that the UV/0.005 wt.% Pt/TiO2 process was capable of efficiently decomposing gaseous DCM in air.

Autoclaving of food wastes (FW) for the resource recovery and reutilization was studied using the pilot plant scale. Experiments were conducted at various temperatures of 408, 428, and 438 K and times of 15 and 60 min. The in-filled steam to the autoclave was supplied by the incineration plant with a gauge pressure of 7 kg/cm2 and a temperature of 443 K or above. The results obtained from the experiments show that the less energy- and time-consuming autoclaving conditions (408 K and 15 min, denoted as Case A408-15) are effective. Comparisons of the properties and characteristics of autoclaved FW (FWA) of Case A408-15 with those of FW are made. The wet bulk volume and wet bulk density of FW A are dramatically reduced to 15.64% and increased to 313.37% relative to those of FW, respectively. This makes the subsequent processing and reuse for FWA more convenient than FW. The autoclaving results in an increase of carbon content and a decrease of nitrogen content, and thus an increase of the C/N ratio of FWA. The contents of sulfur, hemi-cellulose, and cellulose of FWA are also reduced. All these fluctuations are beneficial for making compost or other usages from FWA than FW. The autoclaved liquid product (LA) separated from FWA and liquid condensate (LC) from the released gas possess high COD and TOC. These two liquids can be mixed for use as liquid fertilizers with proper conditioning. Alternatively, further anaerobic digestion of the mixture of FWA, LA, and LC can offer enhanced biogas production for power generation. All these thus match the appeal of sustainable materials management and circular economy. The emitted gas from autoclaving contains no CO and some hydrocarbons. Suitable air pollution control is needed. The results and information obtained are useful for the proper recovery and reuse of abundant food wastes from domestic households and food industries.

This study investigated the photo-decomposition kinetics of toluene in indoor air pollution by ultraviolet light using ultraviolet light emitting diodes (UVLEDs) instead of the more traditional ultraviolet lamp emitting at 254 nm (UVC) or 365 nm (UVA). The study was conducted at different humidities (RHs) and energy efficiencies of the lamps. Experiments were conducted over a range of residence times between 20 and 450 min, relative RHs of 0—50% and toluene concentrations between 20 and 350 ppm. Photo-catalytic decomposition of toluene at various initial concentrations and moisture contents were elucidated according to the Langmuir—Hinshelwood model. The reaction kinetics of the three light sources over 0.5 g of silver titanium oxide (Ag/TiO2) are proposed. A comparison of the simulation results with the experimental data was also made, indicating good agreement. The magnitudes of average energy effectiveness (Ee) under various RHs at the same degradation efficiency (η) were in the order of UVLED (6.7 × 10-4 mg · kW-1 · h-1) >UVC (1.1 × 10-4 mg · kW-1 · h-1) >UVA (9 × 10 -5 mg · kW-1 · h-1). The UVLED uses a lot less energy in comparison with traditional UV lamps. Thus, this study shows the feasible and potential use of UVLED for photocatalysis in the indoor environment with the advantage of energy conservation and greater security.

In this study, a plasmatron reactor was used for gasifying the waste of distillers grains at different temperatures (773, 873, 973 K) and water flow rates (1, 2, 3 mL min(-1)), which were heated to produce steam. Among all the gas products, syngas was the major component (88.5 wt.% or 94.66 vol.%) with temperatures yielding maximum concentrations at 873 K with a relatively high reaction rate. The maximum concentrations regarding gaseous production occurring times are all below 1 min. With the increase of steam, the recovery mass yield of syngas also increases from 34.14 to 45.47 approximately 54.66 wt.% at 873 K. Water-gas reactions and steam-methane reforming reactions advance the production of syngas with the increase of steam. Furthermore, the water-shift reaction also increases in the context of steam gasification which leads to the decrease of CO(2) at the same time.