Abstract: Recently, there has been a lot of interest in the synthesis and application of nanoparticles with anisotropic morphologies. The focus of this study has been to use a biologically mediated, low temperature approach for the synthesis of zinc oxide nanoflowers. “Green” methods have a number of advantages over conventional approaches; these include the use of environmentally benign reactants and its economic feasibility. The cell free extract of Chlamydomonas reinhardtii, a fresh water microalga was used to synthesize the nanoflowers. The nanoflowers were composed of individual nanorods that assembled to form flower-like structures. The nanorods measured 330 nm in length and these nanorods self-assembled to form porous nanosheets that were found to measure 55–80 nm. Particle size analysis revealed that the larger porous nanoflowers approximately measured 4 µm. Powder X-ray diffraction studies revealed that the zinc oxide nanoflowers had a hexagonal wurtzite crystal structure. Fourier transform infrared spectroscopy analysis suggested that algal biomolecules were responsible for the synthesis and stabilization of zinc oxide nanostructures. These nanoflowers demonstrate enhanced photocatalytic activity against methyl orange (MO) under natural sunlight. The effects of dye concentration and catalyst dosage on photocatalysis were also studied. The present approach represents a novel, eco-friendly method to synthesize zinc oxide nanoflowers that have potential applications in water treatment and dye degradation. © 2016 American Institute of Chemical Engineers Environ Prog, 35: 1020–1026, 2016

Abstract: Gradual rise in levels of atmospheric carbon dioxide (CO2) due to burning of fossil fuels has become a matter of environmental concern in the recent years. In this alarming situation capturing CO2 and storing it to restrict its release to the atmosphere could be an attractive approach toward mitigation. Photosynthesis has been recognized as the most sustainable means to arrest CO2 from the atmosphere and microalgae; a photosynthetic microorganism has been identified as the potential sequestering candidate with the highest carbon fixing capabilities. Cyanobacteria and algae have developed their own exclusive editions of photosynthetic carbon concentrating mechanisms (CCMs) to aid ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) in efficient CO2 capture. Carbonic anhydrase (CA), a zinc-containing metallo-enzyme has been observed to play a key role in the CCM by catalysing the reversible hydration of CO2 into bicarbonate and a proton thereby helping in fixation of atmospheric CO2. This review gives an account of the importance of the different types of CA enzymes along with its locations, mechanism of action and the various studies on biosequestration of CO2 through microalgae. © 2016 American Institute of Chemical Engineers Environ Prog, 35: 1605–1615, 2016

Abstract: The broad aim of this study is to evaluate empirically the impacts of urbanization along with some other explanatory variables on environmental degradation measured by carbon dioxide emissions for four countries from the South Asian Association for Regional Cooperation (SAARC) region namely India, Bangladesh, Sri Lanka, and Pakistan. Annual time series data over the period of 1982–2013 are used. After, employing various relevant and required statistical tests, the method of least squares has been employed as an analytical technique for parameters estimation. The least squares estimate reveals that the impact of urbanization on the environment found is blended. In cases of Bangladesh and India, the relationship between urbanization growth and environment found is significantly negative, while, the impact of urbanization on environment is significantly positive in case of Sri Lanka and insignificantly positive for Pakistan during the period under the study. The findings of the study suggest that policy makers need to formulate appropriate policy for long term urban planning which can certainly help to mitigate largely CO2 emissions/environmental pollution. © 2015 American Institute of Chemical Engineers Environ Prog, 35: 823–832, 2016

Abstract: This study investigates the use of ozone as a pretreatment process for water containing pharmaceuticals. Experiments were carried out on synthetic wastewater, surface water, and the effluent of wastewater treatment plant. The degradation efficiencies of four groups of pharmaceuticals (antibiotics, estrogens, acidic, and neutral) were studied, and the effect of ozone dose and pH on the degradation efficiency was monitored. A Microtox™ bioassay test was used to evaluate the change in the toxicity of aqueous solutions before and after ozonation. The efficiency of oxidation of antibiotics, estrogens, and neutral pharmaceuticals increased as the ozone dose and pH increased. Ozone input dose of 188.1, 222.3, and 222.4 mg h−1was found to be optimum yielding the highest oxidation efficiency for the studied pharmaceuticals in synthetic wastewater, surface water and effluent of wastewater treatment plant, respectively. An average specific ozone dose of 2.05 for antibiotics, 1.11 for estrogens, and 1.30 mg O3/mg DOC for neutral pharmaceuticals reduced significantly the acute the toxicity of the water solutions and mineralized more than 40%, 33%, and 23% of DOC in less than 1 min. The kinetics of ozone with pharmaceuticals was modeled for synthetic wastewater as an overall second-order reaction with a rate constant ranging from 103 to 106 M−1 s−1. The results indicate the effectiveness of ozone-based advanced oxidation processes in removing emerging pharmaceuticals from water and wastewater. The results showed that ozonation process is more effective than other conventional oxidation processes (Cl2 and ClO2) in eliminating pharmaceuticals and reducing the toxicity of the effluent water or wastewater. © 2016 American Institute of Chemical Engineers Environ Prog, 35: 982–995, 2016

Abstract: Performance of 45 L pilot scale microbial fuel cell (MFC) made from glass fiber-reinforced plastic and ceramic-separators (CS) with multiple electrode assembly was evaluated. Study on effect of external resistance (Rext) varying from 100 to 3 Ω revealed that maximum power (Pmax) of 14.28 mW (37.8 mA current) with chemical oxygen demand (COD) removal of 84 ± 5.1% was observed at Rext of 10 Ω. While evaluating influence of organic loading rate (OLR) from 0.75 to 8 g COD L−1d−1, the MFC showed Pmax of 17.63 mW (42 mA current) and COD removal of 69 ± 5.1% at OLR of 4.5 g COD L−1d−1. Internal resistance (Rint) of 12.4 Ω observed is among the least value reported in literature for larger MFCs. Simplicity in design, ease of fabrication, lower Rint, longevity and low cost CS, which can withstand more hydraulic pressure than polymeric membranes, are the advantages that this MFC offers to make it suitable for field applications. © 2016 American Institute of Chemical Engineers Environ Prog, 35: 1809–1817, 2016

Abstract: This article reviews different methods employed to enhance the yield of solar still by increasing the surface area of water. As the area of stacked water increases, there is a greater possibility of an increase in temperature of the water and hence the evaporation rate from the top layer of basin water. Wick materials—though there may be evaporation rate and have a good capillary effect to absorb the saline water, intolerable smell, and turbidity—contribute to increased operational and maintenance cost. Use of sponge materials increases the surface area of water; as salt is trapped in pores of the sponge, yield of fresh water was decreased. It is concluded that the surface area of water in the solar still can be improved by using sensible heat storage material such as salt or/and molten salt, encapsulated in cuboid boxes. © 2015 American Institute of Chemical Engineers Environ Prog, 35: 815–822, 2016

Abstract: The present study focused on the hydrofluoric acid (HF) free synthesis of chromium based metal organic framework, MIL-101(Cr) and its application for hydrogen storage. MIL-101(Cr) has been synthesized hydrothermally using HF, acetic acid, perfluorobenzoic acid, and without acid. The characterization of the synthesized materials were carried out using powder X-ray diffraction, scanning electron microscopy, thermogravimetric analysis, and surface area (BET) by nitrogen adsorption isotherm at 77 K. The results demonstrated that acetic acid mediated synthesized MIL-101(Cr) exhibited higher surface area and pore volume than those synthesized with other organic acids. This may be due to the enhanced dissolution of terephthalic acid in the presence of acetic acid which facilitates the formation of MIL-101(Cr) nuclei during the synthesis. A comparison of conventional and HF free-synthesized MIL-101(Cr) for hydrogen adsorption capacity determined at 77 K up to 4500 kPa revealed that MIL-101(Cr) synthesized using acetic acid exhibited higher hydrogen adsorption capacity (5.6 wt %) than the MIL-101(Cr) synthesized with perfluorobenzoic acid (3.7 wt %) and without acid (4.8%). However, it is slightly less than the H2 adsorption capacity of MIL-101(Cr) synthesized using HF (6.1 wt %). The higher H2 adsorption capacity of MIL-101(Cr) synthesized using acetic acid can be attributed to the better terephthalate–chromium interaction which facilitates the formation of more crystalline product thereby creating more unsaturated metal centers in MIL-101(Cr). The present study suggested that acetic acid may be a suitable alternative for highly corrosive and hazardous HF which led to easier preparation of MIL-101(Cr) for the large-scale production and applications. © 2015 American Institute of Chemical Engineers Environ Prog, 35: 461–468, 2016

Abstract: Lignocellulose is the uppermost limiting factor influencing the maturity process of agricultural waste compost. The purpose of this study was to determine the promotion of lignocellulose degradation by the inoculants DN-1 during co-composting of cattle manure with rice straw. Lignocellulose content, functional groups, and microscopic structure were investigated by the chemical determination, the Fourier transform infrared spectroscopy (FTIR) analysis, and the scanning electron microscopy (SEM) observation, respectively. The chemical determination indicated that the inoculants DN-1 promoted the degradation of cellulose and hemicellulose in the initial stage of composting and the degradation of lignin in the later thermophilic stage. After composting, the degradation rate of cellulose, hemicelluloses, and lignin in the inoculated compost was 62.57%, 67.14%, and 42.54% respectively, while those in the natural compost was only 31.27%, 47.57%, and 22.21%, respectively. During composting, in the inoculated compost, the characteristic absorption peaks of cellulose and hemicellulose (at 3312, 2930, 1050, and 895 cm−1) and lignin (at 1506 cm−1) decreased noticeably, while in natural compost, except for the peak at 1050 cm−1, no obvious changes in these peaks were observed, confirming that the inoculants were effective in promoting the degradation of lignocellulose. The SEM images provided clear morphological evidence of lignocellulose degradation during composting. After composting, the serious degradation of parenchyma tissue (which is composed of cellulose and hemicellulose mainly) and sclerenchyma tissue (which is composed of lignin mainly) was observed in the inoculated compost. While in the natural compost, only the partial degradation of parenchyma tissue occurred, no obvious degradation of sclerenchyma tissue was found at the end of composting. © 2015 American Institute of Chemical Engineers Environ Prog, 2015

Abstract: The treated sawdust was examined to discover its ability in adsorption of Basic Red 46 (BR46) and Reactive Red 196 (RR196). Response surface methodology was employed to evaluate the effects of initial dye concentration, solution pH, adsorbent dosage, and contact time on the process. The experimental results showed the maximum removal of 99.72 and 98.82% for BR46 and RR196, respectively. The percentage of dye removal decreased with increasing initial dye concentration. The alkaline pH for BR46 cationic dye and the acidic pH for RR196 favored the dye adsorption. The maximum removal rate was attained at the adsorbent dosage of 4 g L–1 for BR46 and 4.5 g L–1 for RR196 within the equilibrium time of 40 and 55 min, respectively. The Langmuir model best described the data with predicting the maximum adsorption capacity of 13.94 and 13.39 mg g–1 for BR46 and RR196, respectively. Kinetic studies revealed the pseudo-second order kinetic model best fitted the experimental results, suggesting that the chemisorption controlled adsorption of both dyes onto treated sawdust. The findings revealed that the sawdust as a recycled waste could be used for efficient removal of cationic and anionic dyes from aqueous solutions. © 2016 American Institute of Chemical Engineers Environ Prog, 35: 1078–1090, 2016

Abstract: Recent strategies on fuel-development to reduce oil dependency to mitigate greenhouse gas emissions and to utilize domestic resources have generated interest in the search for alternative sources of fuel supplies. In this context, the industrial waste may be regarded as potential alternatives for biogas production. This study entails a detailed characterization of tea waste and food waste to evaluate their potential as an alternate feedstock to cattle dung for biogas production. The samples were characterized for volatile matter, moisture content, ash content and carbon hydrogen nitrogen (CHN). Property analysis of the biomass was also done by scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). The volatile matter content in tea and food waste was found to be 64.17% and 36.05% respectively, which is quite encouraging. The carbon-to-nitrogen (C:N) ratio, chemical oxygen demand and total solids of the sample also attributed its suitability for biogas production. The thermal behavior and heating values interpreted higher lignin content in tea waste. The lab scale study was conducted with combination of food waste/cattle dung and tea waste/cattle dung that showed higher biogas production in comparison to cattle dung alone implying their potential as biogas feedstock. © 2016 American Institute of Chemical Engineers Environ Prog, 35: 1247–1253, 2016

Abstract: In this study, rice husks (RHs), an agriculture by-product, were used as precursor for the production of activated carbon by chemical activation with ZnCl2-CuCl2 composite activator. The effect of process variables, such as ZnCl2 concentration, CuCl2 concentration, activation temperature, and activation time, were investigated. The optimal process condition was obtained through orthogonal test. Then the morphology, pore structure, and surface chemistry of rice husk-based activated carbon (RAC) were analyzed. When using 5 mol/L ZnCl2 and 0.4 mol/L CuCl2 at the carbonization temperature of 500°C for 1.5 h, the BET surface area of the produced activated carbon was as high as 1924 m2/g and the total pole volume reached 1.493 cm3/g. The surface area was strongly affected by ZnCl2 concentration and the subsequent activation temperature. RAC prepared under the optimum conditions had remarkable adsorptive properties and notable treatment effect for fuchsine. © 2015 American Institute of Chemical Engineers Environ Prog, 2015

Abstract: Lignocellulosic materials consist of 10−30% lignin by weight and 40% by energy (Perlack et al., 2005). As the highest energy component of plant biomass, lignin is composed of phenol units. Eco-friendly degradation of lignin in ILs provides an important way to utilize it efficiently. In this study, 1-methyl-3-benzylimidazolium chloride (BnMIMCl) and 1-methyl-3-benzylimidazolium trichloroacetate (BnMIMTFA) were applied for degradation liquefaction of lignin. The highest liquefaction efficiency of 75.45% was obtained under the optimized condition. This attributed to the good dissolving capability and assistance of ILs to lignin during the degradation. GC-MS analysis showed that 60% of low molecular products were phenols. © 2015 American Institute of Chemical Engineers Environ Prog, 2015

Abstract: Increased energy demand of the world poses risk because of the limitation of fossil fuel resources. Moreover, global warming has been reached to an alarming level because of carbon dioxide emissions originated from different anthropogenic activities. Therefore, alternative energy sources are needed, and in this sense, anaerobic digestion of microalgal biomass for biomethane production might be one attractive approach. In this study, biogas production from biomass of Chlorella vulgaris grown on wastewater with air as nutrient was investigated at mesophilic and thermophilic conditions. Moreover, the digestate of anaerobic reactors was tested for its biofertilizer potential. Experimental results indicated that the average biogas and biomethane production per gram of volatile solids (VSs) was 238 and 99 mL/g VS, respectively. The removal efficiency of chemical oxygen demand (COD) was 59% and 46% for mesophilic and thermophilic reactors, respectively. Acetic and isobutyric acids were the main volatile fatty acids detected in the reactor effluent. They ranged between 2.5–5.0 and 5–15 mM, respectively. When the fertilizer quality of the digestate of the anaerobic reactors fed with microalgal biomass is considered, it was observed that it does not correspond to any significant value as a fertilizer and soil conditioner. However, the fertilizer potential of the digestate of the reactors can be improved by increasing the influent COD concentration and the loading rate. Then, it can be used as an ingredient to produce commercial fertilizers. Coupling wastewater treatment with renewable energy production from the produced microalgal biomass not only decreases the sludge to be handled and associated costs but also provides a sustainable means of wastewater treatment. © 2016 American Institute of Chemical Engineers Environ Prog, 35: 936–941, 2016

Abstract: A new hybrid approach by integrating the support vector machine (SVM) with firefly algorithm (FFA) is proposed to estimate shape (k) and scale (c) parameters of the Weibull distribution function according to previously established analytical methods. The extracted data of two widely successful methods utilized to compute parameters k and c were used as learning and testing information for the SVM-FFA method. The simulations were performed on both daily and monthly scales to draw further conclusions. The performance of SVM-FFA method was compared against other existing techniques to demonstrate its efficiency and viability. The results conclusively indicate that SVM-FFA method provides further precision in the predictions. Nevertheless, for daily estimations, the applicability of proposed method could not be feasible owing to high day-by-day fluctuations of parameters k, whereas the results of monthly estimation are completely appealing and precise. In summary, the SVM-FFA is a highly viable and efficient technique to estimate wind speed distribution on monthly scale. It is expected that the proposed method would be profitable for wind researchers and experts to be used in many practical applications, such as evaluating the wind energy potential and making a proper decision to nominate the optimal wind turbines. © 2015 American Institute of Chemical Engineers Environ Prog, 2015

Abstract: In order to effectively improve the composite regeneration performance of the diesel particulate filter in vehicle, a fuzzy gray correlation analysis model based on the composite regeneration influencing factors of diesel particulate filter was established using the cosine value of fuzzy membership and Euclidean distance formula. And, on the basis of experimental data from three-dimensional computational fluid dynamics simulation, the fuzzy gray correlation analysis on important degree of characteristic indexes, which has influence on the composite regeneration performance of diesel particulate filter, was conducted. Moreover, the method of Lagrange function was used to solve the fuzzy gray affiliate degree based on the results of this fuzzy gray correlation analysis. The effectiveness indexes of overall performance of the diesel particulate filter composite regeneration time, regeneration peak temperature and regeneration efficiency were also obtained. The results showed that the amount of ceria-based additive had the greatest influence on the regeneration time among all the characteristic performance indexes of diesel particulate filter composite regeneration. Similarly, it could be concluded that the exhaust oxygen concentration and exhaust temperature respectively had the greatest influence on the regeneration peak temperature and regeneration efficiency. In addition, the regeneration time had the greatest influence on the overall performance of diesel particulate filter composite regeneration while the regeneration efficiency took the second place and the influence of the regeneration peak temperature was the minimum. The results of this article showed theoretical significance and reference value for optimization analysis and control of diesel particulate filter composite regeneration process. © 2015 American Institute of Chemical Engineers Environ Prog, 35: 882–890, 2016

Abstract: Synthesis of high-quality graphene oxide from waste graphite recovered from spent mobile phone batteries was investigated. Graphite powders were easily removed from the anodic copper foil of lithium ion batteries opposed to being sent to landfills. Graphene oxide (GO) was prepared by leaching and oxidation of the graphite with a mixture of potassium permanganate and concentrated sulfuric acid. The structure of GO has been studied using Infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and Transmission electron microscopy (TEM). FT-IR spectra of GO indicate the existence of –OH, ketone and -O- groups. Crystalline monolayer and multilayer nano-sized structures of exfoliated graphene oxide sample exhibiting atomically smooth edges were observed by SEM and TEM. © 2016 American Institute of Chemical Engineers Environ Prog, 35: 1485–1491, 2016

Abstract: The fluoride uptake performance of raw biomass and its superheated steam activated biochar of Colocasia esculenta stem were investigated in the present study. The sorption process was optimized by response surface methodology (RSM) and a 24 full factorial experimental matrix was developed by central composite design (CCD) approach. The influence of four process parameters viz. pH (4.25–10.75), temperature (31.25–63.75°C), adsorbent dosage (8 to 20 g/L) and contact time (62.25–180.75 min) on fluoride uptake was studied in a series of batch sorption experiments. The processed biomass and its activated biochar were characterized and instrumentally analyzed by BET, XRD, SEM and EDAX. The analysis of variance (ANOVA) was studied by using second order regression model equation to study the process parameters. The maximum fluoride removal using raw biomass and activated biochar were 33.00% and 72.82% respectively at similar parametric conditions, i.e., pH 4.25, temperature 63.75°C, adsorbent dosage of 20 g/L and contact time of 180.75 minutes. The present investigation concludes that activated biochar of Colocasia esculenta stem could be a cost-effective biosorbent for fluoride removal from contaminated water. © 2016 American Institute of Chemical Engineers Environ Prog, 35: 1305–1316, 2016

Abstract: Locally available Indian mustard (Brassica juncea) and Marigold (Tagetes patula) plants can be used in a cost-effective, environment-friendly approach for treatment of landfills developed using heavy metal contaminated Buriganga riverbed sediments. In this study heavy metal uptake by Indian mustard and Marigold plants from heavy metal contaminated Buriganga riverbed sediments were assessed. Initial characterization of the Buriganga riverbed sediments showed concentrations of chromium, lead, copper, and zinc in the sediments higher than the toxicity reference values given for these heavy metals in soil for terrestrial plants, and soil invertebrate. The average background concentration of chromium, lead, copper, and zinc in the Buriganga riverbed sediments were found to be 141.5 mg/kg, 34.9 mg/kg, 38.7 mg/kg, and 287.5 mg/kg, respectively. Hence the newly developed area using such landfills poses a great threat to the surrounding flora and fauna. It was observed that both Indian mustard and Marigold plants accumulated these heavy metals in different parts of the plant from the contaminated sediments and were able to maintain a growth rate of more than 90% compared to that in noncontaminated soil. The results indicated rapid phytoextraction of most heavy metals by the Indian mustard during its final growth phase, whereas rapid phytoextraction of most heavy metals was observed in case of Marigold in its initial growth phase. Total chromium, lead, copper, and zinc uptakes (in mg/kg of plant dry weight) by Indian mustard plant in 12 weeks were 102.6, 28.9, 53, and 1861.5, respectively. The uptakes (in mg/kg of plant dry weight) of the same heavy metals by Marigold plant in 12 weeks were found to be 112.3, 104.25, 82.5, and 716.75, respectively. Marigold showed higher uptake efficiency for chromium, lead, and copper, while Indian mustard was found to be more efficient for zinc uptake. Hence both of these plants can be appropriately used as necessary for treating heavy metal contaminated landfills developed using Buriganga riverbed sediments. © 2015 American Institute of Chemical Engineers Environ Prog, 35: 117–124, 2016

Abstract: In present study, biosorption of mercury(II) ions from aqueous solution on Pleurotus eryngii fungal biomass was investigated. Different experimental parameters such as the effects of pH, sorbent dose, initial Hg(II) ion concentration, contact time, and temperature were evaluated systematically. The sorption process was relatively fast and > 98% removal of Hg(II) was achieved within 5 min at pH 7.0. To analyze the suitability of the process and maximum amount of metal uptake, Langmuir and Freundlich isotherm models were applied. The biosorption capacity of P. eryngii fungal biomass was found to be 34.01 mg g−1. Among kinetic models studied, the pseudo-second order was the best applicable model to describe the sorption process. Thermodynamic parameters of Hg(II) sorption were evaluated by applying the Van't Hoff equation which indicates that the sorption process was exothermic and spontaneous by increased randomness at the solid-solution interface. The adsorbed Hg(II) ions were easily desorbed from the fungal biomass using 5 M HCl solution with higher effectiveness and can be reused up to five cycles. The possible nature of cell-metal ion interactions were evaluated by FTIR, SEM, EDX and pHpzc analysis. These examinations indicates the involvement of different electronegative functionalities in the binding of Hg(II) metal ions on the surface. © 2016 American Institute of Chemical Engineers Environ Prog, 35: 1274–1282, 2016

Abstract: The compacted cement stabilized/solidified (S/S) metal contaminated soil could be used for “controlled utilization,” such as road base, quarry rehabilitation, and lagoon closure. However, the complexity and variability of environment, especially the acid rain and alkaline leachate, greatly influence the leaching behaviors of S/S heavy metal contaminated soil and threaten the environment. The leaching characteristics of the compacted S/S samples were investigated over a wide range of pH (2.65, 3.65, 5.00, 7.00, and 10.00). Semidynamic leaching tests were conducted to evaluate the effects of pH on effectiveness and controlling leaching mechanism of compacted cement S/S treated lead (Pb) contaminated soil. Results showed that there was no obviously change of the cumulative fraction of Pb leached (CFL) in weak acid or weak alkaline conditions (pH ranging from 5.00 to 10.00), and the strong acid significantly altered the leaching behaviors of Pb. The calculated values of effective diffusion coefficient (De) and leachability index (LX) indicated that the mobility of Pb2+ was weak and the compacted S/S treatment could be used for “controlled utilization” with environment pH value ranging from 3.65 to 10.00. Especially, the LX value was 8.49 when the compacted S/S sample was immersed in the leachant with pH 2.65, indicated that the S/S sample was not considered appropriate for disposal. The mechanism controlling Pb2+ leaching from S/S samples at all the pH range (2.65–10.00) appeared to be diffusion, and with pH decreasing in acid conditions, the controlling leaching mechanism somehow was changing from diffusion to surface wash-off. © 2015 American Institute of Chemical Engineers Environ Prog, 35: 149–155, 2016

Abstract: The effects of application of the straw of cadmium accumulating species (Youngia erythrocarpa (cadmium hyperaccumulator), Bidens pilosa (cadmium hyperaccumulator), Solanum photeinocarpum (potential cadmium hyperaccumulator), and Siegesbeckia orientalis (cadmium accumulator)) in cadmium contaminated soil on the growth and cadmium accumulation of Galinsoga parviflora were studied. The root biomass, stem biomass, shoot biomass, total biomass, and the antioxidant enzyme activity of G. parviflora were increased by application of the straw of Y. erythrocarpa. The straw of Y. erythrocarpa, S. orientalis, and B. pilosa reduced soil pH, increased the soil exchangeable Cd concentration, and increased the Cd contents in stems, leaves, and shoots of G. parviflora compared with the control. The straw of Y. erythrocarpa and B. pilosa increased the Cd extraction amount in stems, leaves, shoots and the whole plant of G. parviflora compared with the control, with the effect of Y. erythrocarpa higher than that of B. pilosa. Therefore, the straw of Y. erythrocarpa and B. pilosa improved the Cd extraction ability of G. parviflora from cadmium-contaminated soil, and the straw of Y. erythrocarpa demonstrated to be the best material. © 2015 American Institute of Chemical Engineers Environ Prog, 2015

Abstract: The article looks at the integration of crystalline and thin film (a-Si) floating photovoltaic (PV) arrays for electricity generation in remote mine sites. Floating PV arrays rather than regular ground mounted PV arrays are considered more suitable for the site because it decreases the environmental impacts—in terms of not requiring landscaping or deforestation. The research provides a techno-economic analysis for the integration of varying levels of PV with 40 MW of diesel generation. The main challenge was the consideration of the gen sets part load together with the variability of the solar resource at the site. Applications of alternative technologies at remote mine sites are fairly limited. Results show that at a diesel fuel cost greater than $129c/L a-Si floating PV would offer some financial benefits. At this price, this is not applicable to floating crystalline PV arrays because the infrastructure required to keep them floating would offset the cost savings from the PV array. Further savings could be achieved if energy storage or load shedding could be implemented at the mine, or extra revenue could be generated through carbon credits. Solar energy for remote mine sites is not a solution to 100% of its electricity demands, unless an energy storage is available, so diesel generation is still a requirement. © 2015 American Institute of Chemical Engineers Environ Prog, 35: 898–905, 2016

Abstract: This study was performed to investigate the latent potential of biomass gasifier waste material (BGWM) as an adsorbent for removal of Cr (VI) from aqueous solution. The present work also proposes an alternate use of gasifier refuge BGWM with great economic feasibility. The effects of initial pH, BGWM concentration, Cr(VI) concentration, temperature and contact time were investigated on the removal of Cr (VI) from aqueous solution. The maximum removal of Cr (VI) was found to be 99.67% at optimum condition of initial pH 2, contact time 80 min, initial Cr (VI) concentration 10 mg L−1, adsorbent dose 5 g L−1, agitation speed 120 rpm, and temperature 35°C. The adsorbent was characterised by SEM, EDX, XRD, BET and FTIR analysis to get important information about its effective application for Cr (VI) removal. The BET surface area of 165.287 m2 g−1 for BGWM was found comparable to that of commercial silica. Batch adsorption experiments showed that pseudo-second-order kinetics model and Langmuir isotherm model fitted the adsorption data very well. Thermodynamic parameters revealed the feasibility, spontaneity and endothermic nature of Cr (VI) adsorption onto BGWM. © 2015 American Institute of Chemical Engineers Environ Prog, 2015

Abstract: In this article, we report results of experiments on covalent immobilization of Candidia rugosa lipase enzyme on modified multiwall carbon nanotubes (MW‐CNTs) for oily wastewater treatment application. MWCNTs were produced using chemical vapor deposition (CVD) and surface‐modified by nitric acid and organic cross‐linkers. Successful attachment and high enzyme loading up to 30 wt % was confirmed via FTIR and TGA analysis. Enzymatic activity and loading, which are dependent on the oxidized MWCNT surfaces, cross‐linker types and concentrations, resulted with high thermal and operational stability in the microenvironment conditions. This demonstrates the potential for improved resistance to the severe conditions in industrial applications. Furthermore, the CNTs‐immobilized enzyme yielded a catalytic activity about 93 times higher than those immobilized on other reported support materials. Up to 98% biological activity retention was also achieved, marking a significant improvement over literature‐reported activities (1–20%). Titrimetric analysis of hydrolyzed samples using MWCNT‐Lipase (after 1 hr reaction time at 37°C) resulted in an enzymatic activity increase of about five times over those from lyophilized lipase. © 2016 American Institute of Chemical Engineers Environ Prog, 35: 1441–1449, 2016

Abstract: The decomposition quantitative model of household energy-related carbon emission in Guangdong is established based on the extended Kaya identity with the Logarithmic Mean Divisia Index (LMDI) method; influence factors of household energy-related carbon emission are decomposed into eight factors, energy price, average consumption propensity, and urban–rural structure of population included in the model. Results show that total direct household energy-related carbon emission in Guangdong province show increasing trend from 1995 to 2012. Oil and electric power consumption are two main source of household carbon emission. Results of decomposition show that resident's living standard has the largest contribution to the increase of carbon emission, which is the first promoting factor to household energy-related carbon emission, followed by energy use level. Energy price has the largest contribution to the reduction of carbon emission, which is the first inhibiting factor, followed by average consumption propensity. Guangdong can realize household energy-related carbon mitigation effectively by the following four measures, namely (1) Adjust energy structure, especially energy structure of power generation, enhances the proportion of nuclear power, (2) Improve energy price mechanism, (3) Optimize urban–rural structure of population, (4) Drive application of home intelligent energy management technology, to realize automatic home energy-saving control. © 2015 American Institute of Chemical Engineers Environ Prog, 2015

Abstract: This study deals with energy and exergy analyses of a four stroke, four cylinders, naturally aspirated, direct-injected diesel engine fueled with diesel and peanut biodiesel. Energetic and exergetic performance parameters of the engine for each fuel were computed and compared with each other. The effect of varying dead state temperatures on exergetic parameters was also investigated. It is concluded that peanut biodiesel indicated similar performance with diesel fuel in terms of the energy and exergy efficiencies. Energy efficiencies of the engine fueled with diesel and peanut biodiesel were determined to be 35.26% and 34.37% while the corresponding exergy efficiencies were calculated to be 33.09% and 32.02%, respectively. The exergy efficiency values for fuels decreased from 35.39 to 31.34% with increasing the dead state temperature from 0 to 35°C. © 2015 American Institute of Chemical Engineers Environ Prog, 2015

Abstract: Phytophthora sojae is the most damaging fungal pathogen for soy plants. Rhamnolipids produced by Pseudomonas aeruginosa were investigated for the antimicrobial effects against both P. sojae mycelia and zoospores. Of particular importance is the effectiveness against zoospores because P. sojae spreads infection primarily via zoospores. Mycelial growth on agar plates was evaluated with three medium compositions and the rhamnolipid effect compared for each medium. Against zoospores, the effects were examined with the rhamnolipid mixture and its separated mono- and di-rhamnolipids. The zoospore study was done in small dose increments to identify the minimum concentrations that cause all zoospores to lyse or stop moving. Rhamnolipids at 100 and 1000 mg L−1 inhibited the mycelial growth by up to ∼30%. Rhamnolipids killed the zoospores much more effectively. The rhamnolipid mixture and its mono- and di-rhamnolipid fractions were similarly effective; the mixture might be slightly more potent, requiring only 8–20 mg L−1 (14–34 µM) concentrations. © 2015 American Institute of Chemical Engineers Environ Prog, 2015

Abstract: To use the visible light in photodegradation reactions efficiently, graphene–TiO2 nanocomposite was photosensitized using tetrakis(4-carboxyphenyl)porphyrin. To investigate the effect of graphene as well as dye sensitization on the photoactivity of the synthesized photocatalyst, photocatalytic properties and photocurrent responses of the prepared samples were examined under visible light irradiation. A twofold increase of photocurrent response in the TG nanocomposite photosensitized with porphyrin (TGP) compared to TG (3%) nanocomposite provides an evidence of the effective influence of the porphyrin photosensitizer in the visible light photoactivity enhancement. There is a complete correspondence between the photocatalytic activity and photocurrent response of the photocatalysts. The photocatalytic properties of the photocatalysts were carried out in the degradation of methyl orange and bisphenol A under visible light irradiation. It was determined that TGP compound was stable after photocatalytic process and degraded 93% of methyl orange and 85% of bisphenol A in 240 min under visible light irradiation. Furthermore, the mechanism of investigation of the photocatalytic process determines that O2.− and OH. are the main reactive species for degradation of methyl orange and bisphenol A over the TGP compound under visible light irradiation. © 2015 American Institute of Chemical Engineers Environ Prog, 2015

Abstract: In this study, the microalgae–bacterial culture, composed of Chlorella vulgaris and activated sludge, was cultivated under starvation condition by controlling synthetic wastewater concentrations. After 8-day culturing, nutrients such as organic carbon, ammonium nitrogen and phosphate were basically removed. The dynamic formation phases of the microalgae–bacterial consortium were identified to microalgae adsorbed by sludge flocs, new bacteria adhesion on microalgae and bacteria uniformly distributed and attachment and detachment of biomass in balance. The consortiums had much better settle-ability than pure microalgae, and this phenomenon was particularly obvious in starvation term. Lipid accumulation of microalgae was also critically influenced by starvation cultivation, lipid content and lipid productivity of bioreactor with 5% initial wastewater (IW) were 17.1% and 0.045 g (L day−1)−1. This study gave a new insight into formation processes of microalgae–bacterial consortium, and confirmed that starvation term was an effective strategy to enhance the consortium settle-ability and lipid accumulation capability. © 2015 American Institute of Chemical Engineers Environ Prog, 2015