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Contamination of heavy metals has always been a pressing concern. The dry-wet alternately treated carboxymethylcellulose bentonite (DW-CB) was successfully prepared by intercalating bentonite (BT) with carboxymethyl cellulose (CMC) obtained by solvent processes using enzymatically digested wastepaper as cellulosic raw material, and the adsorption capacity of Cu2+ on DW-CB in aqueous solution was investigated. A 98.18 ± 2.31 % removal efficiency was achieved by 4 g/L of DW-CB after 8 h in a solution containing 100 mg/L of Cu2+, which were 4.1 times and 1.5 times of that of BT and adsorbent prepared without alternating dry-wet process, respectively. The introduction of -COOH groups during the preparation of DW-CB enhanced the electrostatic interaction between DW-CB and Cu2+, which was the main driving force for Cu2+ removal. The pseudo-first-order kinetic model and Langmuir model better described the adsorption process and adsorption capacity of Cu2+ on DW-CB. DW-CB still showed high removal of Cu2+ (19.61 ± 0.99 mg/g) in the presence of multiple metal ions, while exhibiting the potential for removal of Zn2+, Mg2+ and K+, especially Mg2+ (22.69 ± 1.48 mg/g). However, the interactions of organics with Cu2+ severely affected the removal of Cu2+ by DW-CB (removal efficiency: 17.90 ± 4.17 % - 95.33 ± 0.27 %). In this study, an adsorbent with high targeted adsorption of Cu2+ was prepared by utilizing wastepaper and BT, which broadened the way of wastepaper resource utilization and had good economic and social benefits.

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Solid waste and heavy metal pollution are long-term and challenging subjects in the field of environmental engineering. In this study, we propose a sustainable approach to "treating waste with waste" by utilizing the ultramicropore biochar derived from solid waste distiller's grains as a means to remove Cr(VI) from simulated wastewater and wet phosphoric acid. The biochar prepared in this research exhibit extremely high specific surface areas (up to 2973 m2/g) and a well-developed pore structure, resulting in a maximum Cr(VI) adsorption capacity of 426.0 mg/g and over 99% removal efficiency of Cr(VI). Furthermore, the adsorbent can be reused for up to eight cycles without significant reduction in its Cr(VI) adsorption performance. Mechanistic investigations suggest that the exceptional Cr(VI) adsorption capacity can be attributed to the synergistic effect of electrostatic interaction and reduction adsorption. This study offers an alternative approach for the resource utilization of solid waste distiller's grains, and the prepared biochar holds promise for the removal of Cr(VI) from wastewater and wet-process phosphoric acid.

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Emerging processing methods have been applied in coffee bean processing for improved sensory quality. The processes focus on optimizing the fermentation process of the coffee cherries and beans. This involves various pathways, including the formation of volatiles, flavor precursors and organic acids and the reduction in the concentrations of bioactive compounds. Comprehensive information regarding the effect of these emerging processes on the chemical, biological and sensory properties of the coffee beans is summarized. Emerging processes affected the coffee bean to various degrees depending on the raw material and the method used. The emerging methods promoted the reduction of bioactives such as caffeine and phenolics in coffee beans. Substantial improvement of these processes is needed to obtain coffee beans with improved biological activities. Effort to simplify the methods and optimize the post-fermentation process is crucial for the methods to be easily accessible by the producers and to produce defect-free coffee beans.

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With the decrease in the phosphate rock grade, the minor element ratios (MER) [(Fe2O3 wt% + Al2O3 wt% + MgO wt%)/P2O5 wt%] of wet-process phosphoric acid (WPA) exhibits a linear upward trend. This can lead to a huge challenge for the high-quality production of feed calcium phosphate salt (FCPS). In the present study, we proposed a novel and economical strategy to precipitate Al3+ and Mg2+ via the formation of aluminofluoride complexes (NaMgAlF6·H2O) with the anhydrous sodium sulfate (Na2SO4) and hydrofluoric acid (HF) as precipitation agents. Because of the low solubility of the complexes in WPA, the removal efficiencies of Al3+ and Mg2+ ions could reach 99.5% and 64.8%, respectively. The maximum mass loss of P2O5 was less than 0.5%. The precipitates could be separated and converted into the HF and Na2SO4 for reuse, thus further decreasing the cost of WPA purification.

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The pseudocereal grain, Quinoa (Chenopodium quinoa Willd.), has a great nutritional value due to its high contents of proteins, fiber, minerals, and vitamins. However, saponins naturally present outside the grains represent an obstacle to their consumption as human food. Before consumption, the grains are subjected to various treatments, which alter their nutritional value. In an attempt to eliminate the maximum of saponins using the wet process, while minimizing the washing conditions and preserving the nutritional quality, we explored the effects of several parameters, including volume of water, treatment time, soaking time, number of washing, and water temperature, followed by an optimization process using Box-Behnken Design, and finally, the impact of this process on the physicochemical and techno-functional properties of six quinoa genotypes seeds was evaluated. As a result, the variation of the treatment time, volume, and temperature of the water positively affected the saponins leaching. According to the quadratic model, the maximum percentages of eliminated saponins (96.53%-96.77%) were found at a temperature of 50°C, treatment times from 60 to 69 min, and water volumes from 6.99 to 7.50 mL per gram of seeds. The optimized method did not affect the proteins and microelements content (Zn, Mn, B, Mo), while a slight decrease of macro-elements (K, P, Ca, S, Mg) was noted in the level of some genotypes. On the other hand, a significant improvement of the techno-functional properties such as water and oil holding capacity was noted, with a sharp drop-in emulsifying activity in all genotypes without affecting the standard values of pH (6.4-6.8) and moisture content (10%-11%) of the seeds. Hence, the optimized method showed to be a more potential method for saponins removal than the currently used dry method.

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A large amount of stone powder is produced during the production of machine-made sand. This research aims to study the effect of wet-process tuff silt powder (WTSP) dosages (as an alternative sand material to utilize waste stone powder and reduce environmental hazards) on reactive powder concrete's (RPC) mechanical performance. The physical and chemical properties of WTSP were analyzed as per relevant standards. This study prepared RPC samples with various WTSP content (0%, 6%, 12%, and 18%) to replace quartz sand at the same water-binder ratio (0.14) and allowed the samples to cure for 3 days, 7 days and 28 days prior to unconfined compression testing and flexural testing. Scanning electron microscopy (SEM) and Mercury Intrusion Porosimetry (MIP) testing were also carried out to observe the evolution of macroscopic properties in response to replacing part of quartz sand with the same amount of WTSP. The results show that the developed flexural and unconfined compressive strength (UCS) decreases slowly with a greater dosage of WTSP. However, when the WTSP content is 12% or less, the RPC made with WTSP satisfies the industrial application threshold regarding mechanical properties. For RPC samples containing more than 12% WTSP, the UCS and flexural strength showed a dramatic drop. Thus 12% of WTSP content was deemed the maximum and the corresponding UCS of 104.6 MPa and flexural strength of 12 MPa for 28 days of curing were the optimums. The microscopic characteristics indicate that the addition of WTSP can effectively fill the large pores in the RPC micro-structure, hence reducing the porosity of RPC. Furthermore, the WTSP can react with the cementitious material to form calcium aluminate during the hydration process, further strengthening the interface. The alkaline calcium carbonate in WTSP could improve the interfacial adhesion and make the structure stronger.

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At least 275 million scrap tires exist in stockpiles in the U.S. The practice of dumping scrap tires in landfills has been an environmental concern. To address this concern, many industries-and regional and national environmental protection agencies-have taken major initiatives to recycle scrap tires. One of the major uses of recycled scrap tires is in crumb rubber products, including rubberized asphalt. Rubberized asphalt is produced by blending ground tire rubber with asphalt to beneficially modify its properties for highway construction. The ground tire rubber (GTR) can be used either as part of the asphalt rubber binder (also known as asphalt rubber), seal coat, cap seal spray, joint and crack sealant or as substitute aggregate (rubber-modified asphalt concrete). Therefore, the largest single market for GTR is asphalt rubber, which consumes approximately 12 million tires, annually. Currently, several Departments of Transportation (DOTs) in the U.S. do not allow use of GTR in asphalt mixes. This is partly due to lack of information, laboratory test data and specifications or special provisions on the use of GTR in asphalt pavements. The current study was undertaken to summarize the available wealth of knowledge, identify research needs, and document the major findings of previous pertinent studies focused on GTR use in asphalt. Significant study findings-consisting of laboratory test results, field observations, and common practices-were documented, including: the use of GTR in asphalt mixes, wet and dry processes, characterization of hot mix asphalt (HMA) containing GTR and GTR performance when combined with virgin materials. In order to promote successful use of GTR, it is imperative to help DOTs develop specifications/special provisions for utilizing rubberized asphalt by collecting data, common practices and specifications utilized by other state DOTs. As a part of this effort, we conducted a survey of construction specifications used by different DOTs that currently allow the use of GTR in asphalt. Since some DOT practices are not readily available in the open literature, this survey proved to be an effective tool for gathering data on the current practices, methods and specifications associated with DOT use of GTR in asphalt pavement.

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This work reports the application of an electromembrane process, Donnan dialysis (DD), for the purification of so-called wet-process phosphoric acid (WPA). Nitric acid is used as the stripping solution to remove metallic cations (mostly Fe3+, Al3+, and Mg2+) that are harmful to the further processing of WPA. The paper first presents a set of experimental data on the measurements of the metallic cation fluxes through a perfluorinated sulfonic acid cation-exchange membrane. Not only WPA, but also synthetic phosphoric acid solutions with mixed metallic cations (MPA) and with a single metallic cation (SPA) were studied. This confrontation confirms (1) that the order of metallic cations fluxes is Mg2+ > Al3+ > Fe3+; (2) that, compared with MPA, the purification effect of WPA causes only negligible change; (3) that, by comparing the DD processes with SPA and MPA solutions, the reason for the low transmembrane fluxes of Fe3+ and Al3+ could be explained by the large ionic charge and large hydrated ion radius. Furthermore, by analyzing the ion composition of membranes equilibrated in SPA solutions, we conclude that the forms of cations in the membrane are most likely Fe3+, Al3+, and Mg2+.

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The management of food waste has been considered an extremely important issue since the 1990s but finding efficient solutions for small and rural communities is still challenging. Anaerobic digestion (AD) may provide interesting opportunities in terms of carbon emissions and economic payback in the long term, but the choice of the correct technology and the spatial scale requires attention. The focus of this study is on a small rural municipality, which is selected as a case study to assess the environmental and economic sustainability of the application of two options for AD (a conventional and an alternative wet process) and two spatial scales (municipality and a consortium of municipalities). Both the AD configurations are examined in terms of biogas exploitation, through a combined heat and power generator, and in combination with a post-composting stage of the digestate. From economic and environmental perspectives, the consortium-scale application of the conventional wet process is expected to generate greater benefits in the long term, as it enables 80% more electric energy production and economic revenues/savings, and avoids carbon emissions. However, before selecting the technology, decision makers should consider the public acceptance of local communities (e.g., the susceptibility to the "not-in-my-backyard" syndrome), as the best technical-economical solution may not be the most appropriate to specific communities. The methodology developed in this paper and the discussion of the results will inform decision makers about how to identify the most appropriate alternative for their purposes.

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The micronano bubble water system (MNBW) generated by a micronano bubble generator (MNBG) has the superior oxidation properties and can improve gas solubility. In the study, a new wet recycling process based on MNBW is proposed to simultaneously remove nitric oxide (NO) and sulfur dioxide (SO2). The important experimental parameters such as initial water pH, initial water temperature, NO and SO2 concentrations, and the presence of oxygen (O2) were investigated to explore the feasibility of desulfurization and denitration with MNBW. The experimental results showed that decreasing initial water pH or increasing initial water temperature and NO and SO2 concentrations were not conducive to the removal of NO or SO2. O2 could promote the removal of NO, but it had no effect on SO2 removal. In addition, SO2 removal efficiency always remained high and did not change obviously during the experimental period. However, NO removal efficiency gradually decreased in the first 50 min and then became stable.

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Coffee is one of the most consumed non-alcoholic beverages in the world. It is well known that some compounds present in coffee beans have important biological activities. In this study, evidence was turned to ßN-alkanoyl-5-hydroxytryptamides (C-5HTs) and to the furokaurane diterpenes cafestol and kahweol, associated with gastric irritation and increasing of blood cholesterol, respectively. Fermentation in coffee post-harvest wet process was induced by three Saccharomyces cerevisiae yeasts (for bakery, white and sparkling wines) as starter cultures. Variations in mass, time, temperature and pH (56 experiments under fractional factorial and mixture experimental designs) were tested. Substantial reductions for C-5HTs (up to 38% reduction for C20-5HT and 26% for C22-5HT) as well as for diterpenes (54% for cafestol and 53% for kahweol) were obtained after treating green coffee beans with 0.6 g of a 1:1:1 mixture the three yeasts for 12 h at 15 °C and pH 4. Caffeine and 5-CQA content, monitored in the green coffee beans, did not change. Therefore, the use of starter cultures during coffee post-harvest wet process has influence on the amount of some important compounds related to health and improves the sensory quality of the beverage.

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The chemistry of pyrazoles has gained increasing attention due to its diverse pharmacological properties such as antiviral, antagonist, antimicrobial, anticancer, anti-inflammatory, analgesic, anti-prostate cancer, herbicidal, acaricidal and insecticidal activities. 1-Phenyl pyrazole-3, 5-diamine, 4-[2-(4-methylphenyl) diazenyl] and 1H- pyrazole-3 (1), 5-diamine, 4-[2-(4-methylphenyl) diazenyl] (2) were synthesized, characterized and encapsulated into liposomal chitosan emulsions for textile finishing. The chemical modifications of cotton fabrics were demonstrated by infrared analysis. Retention of the fabric mechanical properties was investigated by reporting the tensile strength values. Synthesized pyrazole-based compounds were screened for cytotoxicity against skin fibroblast cell line and showed very limited toxicity for both compounds. Antimicrobial potentials of the treated cotton fabrics were tested against bacterial strains E. coli ATCC 8379 and Staphylococcus aureus ATCC 25923.

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Well-aligned ZnO nanorod arrays have been grown on metal-plated polymer fiber via a mild wet process in a newly-designed continuous reactor, aiming to provide wire-shaped photoanodes for wearable dye-sensitized solar cells. The growth conditions were systematically optimized with the help of computational flow-field simulation. The flow field in the reactor will not only affect the morphology of the ZnO nanorod⧹nanowire but also affect the pattern distribution of nanoarray on the electrode surface. Unlike the sectional structure from the traditional batch-type reactor, ZnO nanorods with finely-controlled length and uniform morphology could be grown from the continuous reactor. After optimization, the wire-shaped ZnO-type photoanode grown from the continuous reactor exhibited better photovoltaic performance than that from the traditional batch-type reactor.

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We report on the use of microcrystallization in capillaries to fabricate patterned crystalline microstructures of the low-bandgap ambipolar quinoidal quaterthiophene derivative (QQT(CN)4) from a chloroform solution. Aligned needle-shaped QQT(CN)4 crystals were formed in thin film microstructures using either open- or closed- capillaries made of polydimethylsiloxane (PDMS). Their charge transport properties were evaluated in a bottom-gate top-contact transistor configuration. Hole and electron mobilities were found to be as high as 0.17 and 0.083 cm(2) V(-1) s(-1), respectively, approaching the values previously obtained in individual QQT(CN)4 single crystal microneedles. It was possible to control the size of the needle crystals and the microline arrays by adjusting the structure of the PDMS mold and the concentration of QQT(CN)4 solution. These results demonstrate that the microcrystallization in capillaries technique can be used to simultaneously pattern organic needle single crystals and control the microcrystallization processes. Such a simple and versatile method should be promising for the future development of high-performance organic electronic devices.

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The consumption of milk in China is increasing as living standards rapidly improve, and huge amounts of aseptic composite milk packaging waste are being generated. Aseptic composite packaging is composed of paper, polyethylene, and aluminum. It is difficult to separate the polyethylene and aluminum, so most of the waste is currently sent to landfill or incinerated with other municipal solid waste, meaning that enormous amounts of resources are wasted. A wet process technique for separating the aluminum and polyethylene from the composite materials after the paper had been removed from the original packaging waste was studied. The separation efficiency achieved using different separation reagents was compared, different separation mechanisms were explored, and the impacts of a range of parameters, such as the reagent concentration, temperature, and liquid-solid ratio, on the separation time and aluminum loss ratio were studied. Methanoic acid was found to be the optimal separation reagent, and the suitable conditions were a reagent concentration of 2-4 mol/L, a temperature of 60-80°C, and a liquid-solid ratio of 30 L/kg. These conditions allowed aluminum and polyethylene to be separated in less than 30 min, with an aluminum loss ratio of less than 3%. A mass balance was produced for the aluminum-polyethylene separation system, and control technique was developed to keep the ion concentrations in the reaction system stable. This allowed a continuous industrial-scale process for separating aluminum and polyethylene to be developed, and a demonstration facility with a capacity of 50t/d was built. The demonstration facility gave polyethylene and aluminum recovery rates of more than 98% and more than 72%, respectively. Separating 1t of aluminum-polyethylene composite packaging material gave a profit of 1769 Yuan, meaning that an effective method for recycling aseptic composite packaging waste was achieved.

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