Pilot Scale Research Articles

Monitoring solids content development in pilot-scale through air drying of tissue paper

Abstract This study delves into the dynamic evolution of solids content in a pilot-scale through air drying tissue machine, aiming to enhance comprehension and refine optimization strategies for tissue manufacturing. It focuses on development of solids content throughout the process. Analyzing the interaction between process parameters and solids content provides deeper insights into water removal dynamics. The research employs solid contents monitoring techniques in pilot scale, offering a detailed view of solids content evolution from the wet web’s inception to the final tissue product. It significantly highlights the impact of key parameters, particularly pulp refining, on solids content across all positions of the pilot machine. Additionally, the study emphasizes the influence of vacuum system configurations, identifying the relationship between energy expended in the vacuum system and evaporation energy. Furthermore, the results indicate that compression and air displacement dewatering in vacuum boxes are less speed-sensitive compared to heat-driven evaporation in the TAD- and Yankee cylinders. Solid contents at all positions in the tissue machine correlates between various dewatering elements. Optimizing site-specific dewatering and evaporation strategies can potentially save drying energy in the Yankee drying phase which hold promise for enhanced energy and resource utilization, aligning with demands for sustainable manufacturing practices.

Influence of Process Parameters on the Efficiency of Pervaporation Pilot ECO-001 Plant for Raw Ethanol Dehydration

Pervaporation is a membrane-based process used for the separation of liquid mixtures. As this membrane process is governed by the differences in the sorption and diffusivities of separated components, close boiling mixtures and azeotropic mixtures can effectively be separated. The dehydration of ethanol is the most common application of hydrophilic pervaporation. The pilot scale properties of hydrophilic composite poly(vinyl alcohol) PVA membrane (PERVAPTM 2200) in contact with wet raw bioethanol are presented. The wet raw bioethanol was composed of ethanol (82.4–89.6 wt%), water (5.9–8.5 wt%), methanol (2.3–6.9 wt%), cyclohexane (0.2–2.4 wt%), higher alcohols (0.2–1.3 wt%), and acetaldehyde (0.004–0.030 wt%). All experiments were performed using a SULZER ECO-001 plant equipped with a 1.5 m2 membrane module. The efficiency of the dehydration process (i.e., membrane selectivity, permeate flux, degree of dehydration) was discussed as a function of the following parameters: the feed temperature, the feed composition, and the feed flow rate through the module. It was found that the low feed flow rate influenced the dehydration efficiency as the enthalpy of evaporation caused a high temperature drop in the module (around 25 °C at a feed flow rate equal to 5 kg h−1). The separation coefficient during pervaporation was in the range of 600–1200, depending on the feed composition. The increase in temperature augmented the permeation flux and shortened the time needed to reach the assumed level of dehydration. It was revealed that dehydration by pervaporation using ECO-001 pilot plant is an efficient process, allowing also to investigate the influence of various parameters on the process efficiency.

Pilot-scale production of Bacillus subtilis MSCL 897 spore biomass and antifungal secondary metabolites in a low-cost medium.

Bacillus subtilis is a plant growth promoting bacterium (PGPB) that acts as a microbial fertilizer and biocontrol agent, providing benefits such as boosting crop productivity and improving nutrient content. It is able to produce secondary metabolites and endospores simultaneously, enhancing its ability to survive in unfavorable conditions and eliminate competing microorganisms. Optimizing cultivation methods to produce B. subtilis MSCL 897 spores on an industrial scale, requires a suitable medium, typically made from food industry by-products, and optimal temperature and pH levels to achieve high vegetative cell and spore densities with maximum productivity. This research demonstrates successful pilot-scale (100L bioreactor) production of a biocontrol agent B. subtilis with good spore yields (1.5×109 spores mL-1) and a high degree of sporulation (>80%) using a low-cost cultivation medium. Culture samples showed excellent antifungal activity (1.6-2.3cm) against several phytopathogenic fungi. An improved methodology for inoculum preparation was investigated to ensure an optimal seed culture state prior to inoculation, promoting process batch-to-batch repeatability. Increasing the molasses concentration in the medium and operating the process in fed-batch mode with additional molasses feed, did not improve the overall spore yield, hence, process operation in batch mode with 10g molasses L-1 is preferred. Results also showed that the product quality was not significantly impacted for up to 12months of storage at room temperature. An economically-feasible process for B. subtilis-based biocontrol agent production was successfully developed at the pilot scale.

Investigation of Crypthecodinium cohnii High-Cell-Density Fed-Batch Cultivations

Crypthecodinium cohnii is a marine microalga that can accumulate high amounts of polyunsaturated fatty acids (PUFAs) and thus replace conventional routes of fish oil production. They are associated with the destruction of marine resources and multiple downstream/purification complications. The major drawbacks of using C. cohnii for industrial-scale production are associated with low PUFA productivity. One of the means of increasing the PUFA synthesis rate is to maintain the medium component concentrations at optimal values throughout cultivation, thus increasing PUFA production efficiency, which can result in the successful transfer of the process to pilot and/or industrial scale. The goal of the present research was to develop techniques for increasing the efficiency of PUFA production via C. cohnii cultivation. Multiple experiments were carried out to test and fine-tune the cultivation medium composition and oxygen transfer factors. The biomass yields from individual components, yeast extract, sea salts, and glucose amounted to 5.5, 0.65, and 0.61 g·g−1, respectively. C. cohnii cell susceptibility to mechanical damage was experimentally evaluated. Power inputs of <276.5 W/m3 did not seem to promote cell destruction when Pitched-blade impellers were used. The obtained cultivation conditions were shown to be efficient in terms of increasing the biomass productivity and the omega-3 fatty acid content in C. cohnii. By using the applied methods, the maximal biomass productivity reached 8.0 g·L−1·day−1, while the highest obtained biomass concentration reached 110 g·L−1. A steady increase in the concentration of PUFAs during cultivation was observed from the FTIR data.

Influence of a nanoscale coating on plucking fingers and stainless steel on attachment and detachment of Salmonella Enteritidis, Escherichia coli and Campylobacter jejuni.

Gastroenteritis caused by Campylobacter represents the most common reported foodborne bacterial illness worldwide, followed by salmonellosis. Both diseases are often caused by the consumption of contaminated, insufficiently heated poultry meat. This can result from contamination of the meat during the slaughtering processes. Food contact surfaces like stainless steel or plucking fingers contribute significantly to cross-contamination of poultry carcasses. Modification of these surfaces could lead to a reduction of the bacterial burden, as already proven by successful application in various food industry sectors, such as packaging.In this study, nanoscale silica-coated and uncoated stainless-steel surfaces and plucking fingers were compared on a pilot scale regarding attachment and detachment of Campylobacter jejuni, Salmonella Enteritidis and Escherichia coli.The bacteria did not adhere less to the coated plucking fingers or stainless-steel sections than to the uncoated ones. The coating also did not lead to a significant difference in detachment of Campylobacter jejuni, Salmonella Enteritidis and Escherichia coli from the investigated surfaces compared to the uncoated ones.Our study did not reveal any differences between the coated and uncoated surfaces with regard to the investigated bacteria. In order to achieve a better adaptation of the coating to slaughterhouse conditions, future studies should focus on its further development based on the investigation of specific coating parameters.

Monitoring moisture dynamics in multi-layer cover systems for mine tailings reclamation using autonomous and remote time-lapse electrical resistivity tomography

The dynamics of moisture content in cover systems constructed on mining wastes were monitored at the pilot scale using 2D autonomous, remote, and non-invasive time-lapse electrical resistivity tomography combined with conventional point sensors. A methodology was proposed to process the daily hydrogeophysical datasets from 23 m-long instrumented sections of covers with capillary barrier effects (CCBEs) designed to act as oxygen barriers, and covers with low saturated hydraulic conductivity layers (LSHCCs) designed to limit the water infiltration rate. Hydrogeophysical monitoring suggested that CCBEs were able to maintain high degrees of saturation in the moisture-retaining layer throughout the one-year monitoring period, which would make it an efficient oxygen barrier. Larger spatio-temporal changes in moisture content were observed in LSHCCs and most of the low hydraulic conductivity layers remained below 85% saturation, which was attributed to the combined effect of low precipitation, rapid vegetation development, and water percolation through the cover. The methodology proposed in this pilot-scale "proof-of-concept" study allowed the hydrogeological behavior of the cover systems to be monitored in the 23 m-long instrumented sections using continuous geoelectrical data, which demonstrated that this innovative monitoring technique could be useful for geochemical and geotechnical monitoring programs in large-scale mining waste storage facilities.

Economy of scale for green hydrogen-derived fuel production in Nepal

Opportunity for future green hydrogen development in Nepal comes with end-use infrastructural challenges. The heavy reliance of industries on fossil fuels (63.4%) despite the abundance of hydroelectricity poses an additional challenge to the green transition of Nepal. The presented work aims to study the possibility of storing and utilizing spilled hydroelectricity due to runoff rivers as a compatible alternative to imported petroleum fuels. This is achieved by converting green hydrogen from water electrolysis and carbon dioxide from carbon capture of hard-to-abate industries into synthetic methane for heating applications via the Sabatier process. An economy-of-scale study was conducted to identify the optimal scale for the reference case (Industries in Makwanpur District Nepal) for establishing the Synthetic Natural Gas (SNG) production industry. The techno-economic assessment was carried out for pilot scale and reference scale production unit individually. Uncertainty and sensitivity analyses were performed to study the project profitability and the sensitivity of the parameters influencing the feasibility of the production plant. The reference scale for the production of Synthetic Natural Gas was determined to be 40 Tons Per Day (TPD), with a total capital investment of around 72.15 Million USD. Electricity was identified as the most sensitive parameter affecting the levelized cost of production (LCOP). The 40 TPD plant was found to be price competitive to LPG when electricity price is subsidized below 3.55 NPR/unit (2.7 c/unit) from 12 NPR/unit (9.2 c/unit). In the case of the 2 TPD plant, for it to be profitable, the price of electricity must be subsidized to well below 2 NPR/kWh. The study concludes that the possibility of SNG production in Nepal is profitable and price-competitive at large scales and at the same time limited by the low round efficiency due to conversion losses. Additionally, it was observed that highly favorable conditions driven by government policies would be required for the pilot-scale SNG project to be feasible.

Feedstock/pretreatment screening for bioconversion of sugar and lignin streams via deacetylated disc-refining

Recent publications have shown the benefits of deacetylation disc-refining (DDR) as a pretreatment process to deconstruct biomass into sugars and lignin residues. Major advantages of DDR pretreatment over steam and dilute acid pretreatment are the removal of acetyl and lignin during deacetylation. DDR does not generate hydroxymethylfurfural (HMF) and furfural which are commonly produced from steam and dilute acid pretreatments. Acetate, lignin, HMF, and furfural are known inhibitors during enzymatic hydrolysis and fermentation. Another advantage of deacetylation is the production of lignin-rich black liquor, which can be upgraded to other bioproducts. Furthermore, due to the lack of sugar degradation during deacetylation, DDR has significantly less sugar loss than other pretreatment methods. Previous studies for DDR have primarily focused on corn stover, but lacked the investigative studies of other feedstocks. This study was designed to screen various DDR process conditions at pilot scale using three different feedstocks, including corn stover, poplar, and switchgrass. The impact of the pretreatment conditions was evaluated by testing hydrolysates for bioconversion to 2,3-butanediol. Pretreatment of biomass by DDR showed high-conversion-yields and 2,3-BDO fermentation production yields. Techno-economic analysis (TEA) of the pretreatment for biomass to sugar was also developed based on NREL’s Aspen Model. This study shows that the cellulose and hemicellulose in poplar was more recalcitrant than herbaceous feedstocks which ultimately drove up the sugar cost. Switchgrass was also more recalcitrant than corn stover but less than poplar.

Stratified control of chemical crystallization in a pellet fluidized bed for pH-Adjusted fluoride and phosphate reduction: An experimental study

Chemical crystallization granulation in a fluidized bed offers an environmentally friendly technology with significant promise for fluoride removal. This study investigates the impact of stratified pH control in a crystallization granulation fluidized bed for the removal of fluoride and phosphate on a pilot scale. The results indicate that using dolomite as a seed crystal, employing sodium dihydrogen phosphate (SDP) and calcium chloride as crystallizing agents, and controlling the molar ratio n(F):n(P):n(Ca) = 1:5:10 with an upflow velocity of 7.52 m/h, effectively removes fluoride and phosphate. Stratified pH control—maintaining weakly acidic conditions (pH = 6–7) at the bottom and weakly alkaline conditions (pH = 7–8) at the top—facilitates the induction of fluoroapatite (FAP) and calcium phosphate crystallization. This approach reduces groundwater fluoride levels from 9.5 mg/L to 0.2–0.6 mg/L and phosphate levels to 0.1–0.2 mg/L. Particle size analysis, scanning electron microscopy–energy-dispersive X-ray spectroscopy, and X-ray diffraction physical characterizations reveal significant differences in crystal morphology between the top and bottom layers, with the lower layer primarily generating high-purity FAP crystals. Further analysis shows that dolomite-induced FAP crystallization offers distinct advantages. SDP not only dissolves on the dolomite surface to provide active sites for crystallization but also, under weakly acidic conditions, renders both dolomite and FAP surfaces negatively charged. This allows for the effective adsorption of PO43−, HPO42−, and F− anions onto the crystal surfaces. This study provides supporting data for the removal of fluoride from groundwater through induced FAP crystallization in a chemical crystallization pellet fluidized bed.

Pilot-scale investigation of high-temperature thermochemical energy storage based on the material system CaO/Ca(OH)2 in a bubbling fluidized bed

Utilizing fluidized bed technology for Thermochemical Energy Storage with CaO/Ca(OH)2 is promising for temperatures from 400 °C to 600 °C in industrial-scale applications. Much progress has been made on laboratory scale to develop this technology in recent years. Continuously changing material properties throughout storage cycles, mainly particle breakage, are identified to be challenging for scale-up. Transferability to large-scale systems needs to be examined.Investigations on a pilot scale (di = 257 mm, h = 600 mm, steam for fluidization, 700 °C, 6 barg) are done. A temperature-induced (456 °C discharging and 586 °C charging) and a pressure-induced (1.5 bar discharging and 3.5 bar charging) cyclization is performed. The applicability of standard scaling rules (scaling factor of 17) is possible. Fluidization regimes and breakage rates are transferrable. A detailed experimental characterization of the fluidization properties that are crucial for scale-up of the storage materials is done using a fluidization test rig (di = 140 mm, h = 658 mm, nitrogen for fluidization, ambient temperature and pressure).

Achieving mainstream partial nitritation with aerobic granular sludge treating high-rate activated sludge effluent

New configurations for wastewater treatment plants (WWTPs) are under development to increase their self-sufficiency and sustainability. One is the A-B process, in which the A-stage is designed to maximize the redirection of influent chemical oxygen demand (COD) to the production of biogas. A promising A-stage alternative is the high-rate activated sludge (HRAS). B-stage, on the other hand, can consist of the combined partial nitritation (PN)-anaerobic ammonium oxidation (anammox). In this study, PN with aerobic granular sludge (AGS) was attempted under mainstream conditions at pilot scale. The effluent of a HRAS system – ideally operating at 2 g/L of total suspended solids, 0.5 mg/L of dissolved oxygen and 1 h of hydraulic retention time (52 ± 13 % COD removal) – was fed to the PN-AGS reactor initially inoculated with floccular sludge. Granulation and PN were studied with daily/seasonal fluctuations and without adding external reagents. Selective wasting from the top of the settled sludge bed was found a successful strategy to trigger granular sludge formation. The maintenance of a low sludge volume index (SVI < 100 mL/g) was helpful enough for improved operation of the system (i.e., COD removal and PN). Stable PN was achieved due to the suppression of the nitrite oxidizing bacteria activity by inhibitory levels of free nitrous acid. Finally, working with fast settling biomass at long settling times reduced the influent-biomass-nitrite contact and, thus, denitritation.

Techno-Economic Evaluation of Jet Fuel Production via an Alternative Gasification-Driven Biomass-to-Liquid Pathway and Benchmarking with the State-of-the-Art Fischer–Tropsch and Alcohol-to-Jet Concepts

Around 65% of the mitigation needed for the targeted net-zero carbon aviation emissions in 2050 is expected to come from Sustainable Aviation Fuels (SAFs). In this study, an alternative gasification-driven Biomass-to-Liquid (BtL) concept for the production of SAFs is introduced and evaluated. In particular, a fuel synthesis scheme based on the double-stage fermentation of the produced syngas (syngas → acetic acid → TAGs) is assessed instead of the conventional Fischer-Tropsch (FT) or Alcohol-to-Jet (AtJ) synthesis. The objective of the present work is the techno-economic evaluation of a large-scale (200 MWth) replication of the mentioned BtL concept, whose performance has been simulated in Aspen PlusTM (V.11) with reasonable upscaling considerations and models validated at a pilot scale. The estimated baseline Total Capital Investment (TCI) of €577 million lies in the typical range of €500–700 million that many recent techno-economic studies adopt for gasification-driven BtL plants of similar capacity, while the estimated annual operating costs of €50 million correspond to a 15–40% OpEx reduction compared to such plants. A discounted cash flow analysis was carried out, and a baseline Minimum Jet Selling Price (MJSP) equal to 1.83 €/L was calculated, while a range of 1.38–2.27 €/L emerged from the sensitivity analysis. This study sets the biological conversion of gasification-derived syngas into triglycerides (TAGs) as a promising alternative route for the production of SAFs. In general, gasification-driven BtL pathways, led by the relatively mature FT and AtJ technologies, are capable of thriving in the coming years based on their capability of advanced feedstock flexibility.

Screw reactor design for potato peel pretreatment using the steam explosion

In this article we can observe the scanning by the literature for the pretreatment of steam explosion applied to lignocellulose biomass. A comparison of the chemical and physical characterization of potato peel as a lignocellulose biomass. Besides, the innovative design of a continuous reactor for the potato peel steam explosion process is shown, with specific temperature and pressure conditions on a pilot scale, detailing its parts. Finally, a finite element analysis was performed where stress results were obtained from the reactor material, severity factor, structural analysis and thermal analysis, providing a panorama of the reactor’s behavior with the conditions specific.

Algal Membrane Photo-Bioreactors for Efficient Removal of Emerging Contaminants and Resource Recovery: Current Advances and Future Outlook

Emerging contaminants (ECs), whether of synthetic or natural origin, pose a significant environmental concern, particularly in the context of industrial wastewater. The Algae Membrane Photobioreactor (AMBR) has emerged as a promising technology for ECs remediation. AMBRs effectively remove contaminants due to its considerable flexibility, scalability and a huge surface area for pollutant adsorption. The productivity and efficiency of biomass are increased when it operates in regulated conditions, which minimizes land footprint. AMBR hold immense appeal in favoring integrated circular economy approach and its implementation could achieve the goals for carbon-neutrality and resource recovery by producing value-added products like biofuels, bioplastics, biochemicals, animal feed, biofertilizers and waste re-uses. However, addressing scalability, harvesting efficiency, membrane fouling, algal strain optimization, economic viability, and regulatory approval are some of the challenges faced in order to the advancement of AMBR technology. Life cycle assessments (LCA) and techno-economic assessments (TEAs) are crucial area of future research in implementation of AMBR at pilot scale. LCA evaluates the sustainability of AMBRs with those of conventional techniques. In contrast, TEA examines economic viability parameters like cost-effectiveness, by-product market potential, and policy implications for AMBR implementation. This review emphasizes AMBR's advantages over conventional wastewater treatment technologies in detail, focusing on algal physiology responsible for ECs removal. The innovations related to the design and configuration of AMBRs are also discussed. Several benefits of this technology via integrated circular paradigm are highlighted. Noteworthy pilot case studies, LCA, TEA, challenges and future perspective are spotlighted to underscore the compelling promise of this technology.

A review on the design and fabrication of polydimethylsiloxane thin-film composite membranes (TFCMs) for alcohol permselective pervaporation

Pervaporation-based membrane technology have gained increasing interest due to their energy efficiency and environmental sustainability. Polydimethylsiloxane (PDMS) thin-film composite membranes (TFCMs) have emerged as promising candidates for alcohol permselective applications. Compared to the development of pervaporation membrane for water purification, the optimization progress with the ethanol recovery membrane has been fairly slow and fails to meet requirements of bio-alcohol production. Despite the continuous efforts on membrane materials, the role of structural, physicochemical properties for the forming progress of selective layer on substrate is not a well-attended topic. This paper summarized the design and constructing considerations of PDMS composite membranes for pervaporation from the viewpoint of the transport resistance model, including the effect of selective layer, support layer, and intermediate layer, to deeply understand and precisely regulate the preparation process. We high light the key role of crosslinking and spreading of PDMS on porous support layer in membrane fabrication. The structure-activity relationship between the separation performance of transport structure with the membrane solution properties, substrate pore structure, and the fabrication methods was discussed in detail. It was indicated that the challenges for the TFCMs applied on a pilot or industrial scale include the thickness control, coating and curing time optimization, and solvent issue. Finally, it was expected for further research to optimize the membrane fabrication process, develop novel advanced membrane materials and to explore complex and potential applications the new requirements in industry.

Recovering Phosphorus from Human Urine by Electrochemical Precipitation Using Magnesium Alloy Tailings as Electrodes: Lab Scale and Pilot Scale Studies

Recovering Phosphorus from Human Urine by Electrochemical Precipitation Using Magnesium Alloy Tailings as Electrodes: Lab Scale and Pilot Scale Studies

Bench and Pilot Scale Assessment of 5A Molecular Sieves for Tail Gas Treatment Applications

The modified Claus Process stands out as the predominant method for sulfur recovery within natural gas and crude oil processing facilities. Over the past five decades, in a bid to mitigate the environmental consequences of SO2 emissions, the efficiencies of sulfur recovery units have been enhanced through the integration of tail gas treating units (TGTU). Globally, it is imperative that this sulfur recovery efficiency attains a minimum of 99.95%. This paper delves into both bench- and pilot-scale evaluations of utilizing commercial 5A molecular sieves to extract H2S from specific tail gas streams, as part of scrutinizing the efficacy of a novel tail gas treatment process, delineated in Patent No. US 10662061 B1 (May 26, 2020). The evaluation revealed that employing a 5A molecular sieve to remove H2S from dry tail gas treating presents distinct advantages. Notably, the CO2 adsorption capacity on 5A molecular sieves, being several times that of H2S, did not substantially impair the physical stability and removal capacity of 99.95+% tail gas treating, even after 99 adsorption/desorption cycles. Furthermore, the evaluation demonstrated that extended regeneration at 300°C (as opposed to 250°C) following the 50th and 90th cycles could effectively reinstate the original removal capacity of the 5A molecular sieves. Additionally, the gas emanating from the 5A molecular sieve bed could be reused as regeneration gas for the second stage of the patented process. The H2S removal capacity of 5A molecular sieves from dry tail gas, approximately 1.3mmol/g, aligns with the reported capacities of other adsorbents, which range from 0.37 to 1.53mmol/g. Given the cost-effectiveness of 5A molecular sieves compared to AgY molecular sieves, and based on the evaluation outcomes, it is judicious to conclude that the use of 5A molecular sieves will be a compelling option for future tail gas treating within sulfur recovery units.

Pilot–scale vertical continuous–flow reactors applied to treat rural domestic wastewater at low temperature via aerobic granular sludge

A pilot–scale vertical–flow continuous flow reactors (VF–CFR) was investigated for the treatment of rural domestic wastewater in the cold areas of Northeast China. VF–CFR helps in the creating of aerobic granular sludge (AGS), which improves the sludge concentration and removal efficiency of pollutants. VF–CFR achieved a high removal efficiency of Chemical Oxygen Demand (COD), Ammonia Nitrogen (NH3−N), Total Nitrogen (TN) and Total Phosphorus (TP) with 90 %, 94 %, 75 % and 93 % under the condition of sharp fluctuation of influent quality and temperature. The high–throughput sequencing analysis of the AGS revealed that Flavobacterium was a functional bacterium in the AGS process that had the function of heterotrophic nitrification and denitrification. The field–scale experiment confirmed the superiority of VF–CFR in wastewater treatment efficacy and stability. During the experiment, the concentrations of COD, TP and NH3–N in effluent at different temperatures were well met with the first–class A discharge standard of China (GB 18596–2001). However, there was a risk of exceedance exists in the reduction of TN removal under low temperature conditions.

Influence of Moisture on the Electrochemical Performance of Prelithiated Graphite/SiOx Composite Anodes for Li-Ion Batteries

Abstract Prelithiation is widely recognized as a promising technology to enable the use of high capacity anode active materials such as silicon. Numerous prelithiation techniques have been proposed over the years, with a handful successfully undergoing pilot scale testing. Nevertheless, new challenges arise when moving from optimizing single processes to integrating them into the process chain. A major concern is the stability of prelithiated electrodes against moisture. In this study, we investigated the influence of industrially-relevant moisture levels on the electrochemical performance of prelithiated graphite/SiOx composite anodes in 3-electrode half- and full-cells. We identify several indicators of electrode degradation such as an increase in open circuit potential, a decrease in graphite lithiation potential, and changes in specific charge/discharge capacity. The underlying degradation mechanisms are investigated using electrochemical impedance spectroscopy, X-ray photoelectron spectroscopy, and time-of-flight secondary ion mass spectrometry, which show increased solid electrolyte interphase (SEI)-related interfacial resistances but no clear evidence of SEI degradation. Based on the experimental results, we define a process window for the stability of the investigated electrodes as a function of dew point and exposure time. Our results indicate an encouragingly high stability at dew points up to -40°C for a realistic exposure time of 1 hour

Decamethylcyclopentasiloxane-based sustainable and recyclable polyester fabric whitening using OB-1 fluorescent brightener

Fluorescent whitening agent OB-1 (OB-1) has non-toxicity, chemical stability, exceptional heat resistance, and light stability, and it is widely used in plastic products. However, raw OB-1 is difficult to apply in textiles by exhaustion process. The present investigation employed raw OB-1 without adding an auxiliary to bestow a whitening effect on polyester fabric in a sustainable medium of decamethylcyclopentasiloxane (D5). The Taguchi methodology was employed to optimize the whitening parameters. An L16 orthogonal array was utilized to investigate the optimal conditions for whitening temperature, whitening time, and OB-1 mass, with four whiteness levels. The signal-to-noise ratio was optimized using a larger-is-better approach to enhance the parameter responses. The study analyzed the main effect and interaction plot of multiple factors. The findings indicate that the temperature of the whitening process significantly impacts the whiteness of the polyester fabric (P < 0.05), with a 98.4 % contribution percentage. Under the optimal conditions, a whiteness value of 109.9 was observed for the polyester fabric. Subsequently, various analytical techniques, including FT-IR, SEM, TGA, and XRD, were employed to characterize the treated fabric. The results indicate that using D5 medium was viable for whitening polyester fabric. The study also examined the duration of washing and rubbing to determine their whitening performance. The study evaluated the whitening efficacy of polyester fabric treated with recycled D5 medium and demonstrated its potential for application at the pilot scale in the textile sector.