Product Recovery Research Articles

Multi-stage process for mixed microbial culture production of polyhydroxyalkanoates from sugarcane stillage: Assessment of external nutrient supplementation

Sugarcane stillage is an abundant wastewater from ethanol production. It has drawn considerable interest as a potential feedstock for biotechnological processes aiming at the recovery of energy and value-added products. In this study we explored the use of stillage for the production of polyhydroxyalkanoates (PHA), which are microbial bioplastics with potential to replace conventional plastics in specific applications. As stillage is nutrient deficient, we investigated the impact of external nutrient supplementation on the selection of PHA-producing mixed cultures. Cultures selected under four different total-chemical-oxygen-demand-to-nitrogen ratios (COD.t/N) (15, 30, 40 and 80) were evaluated according to their PHA production performance and microbial composition. The experimental results demonstrated that the most favorable PHA production was achieved for the biomass selected under strict carbon-limiting conditions, with a COD.t/N ratio of 15. This resulted in an overall PHA volumetric productivity of 2.10 g PHA L−1 d−1, a maximum intracellular PHA content of 0.65 g PHA g VSS−1 and a PHA storage yield of 0.71 g CODPHA g CODH.Org−1. The resulting PHA was a copolymer of 3-hydroxybutyrate (73 %mol) and 3-hydroxyvalerate (27 %mol) monomers. The microbial consortium was enriched by members of the Brevundimonas genus, known PHA producers, with a relative abundance of 26.4 %.

Loss and recovery of vegetation productivity in response to extreme drought during 2022 across China

Extreme droughts can severely impact terrestrial vegetation productivity. In the summer of 2022, approximately 32.7% of China’s land area experienced extreme drought conditions, marked by reduced rainfall both in terms of amount and intensity, prolonged consecutive dry days, minimal rainy days, and accompanied by heat waves. While previous studies have reported productivity losses in over half of China’s vegetated areas in 2022, how vegetation productivity recover from extreme drought remains to be clarified. In this study, we utilized the Enhanced Vegetation Index (EVI), Gross Primary Productivity (GPP) and meteorological data to evaluate the extent and pace of vegetation productivity change from loss in 2022 to post-drought recovery in 2023. We also assessed the contributions of seven meteorological variables and two drought-related variables to variations in vegetation productivity in regions affected by extreme drought using machine-learning techniques. Our findings revealed that, in 2022, the average EVI and GPP in regions affected by extreme drought were 2.3% and 8.0% lower, respectively, compared to the baseline period from 2018 to 2021. Soil water content (SWC) emerged as the primary factor contributing to the decline in EVI/GPP, followed by the number of rainy days for EVI and vapor pressure deficit for GPP. In 2023, we observed a significant vegetation recovery, with the average EVI increasing by 2.6% and the GPP rising by 14.9% within the study area compared to 2022. SWC played a dominant role in this recovery, and both EVI recovery and GPP recovery displayed a non-linear response to SWC. Additionally, we identified a threshold effect for SWC on recovery; once SWC increased above a certain threshold, EVI and GPP would recover largely and rapidly. Furthermore, rainfall intensity and rainfall amount emerged as the second most important factors influencing the recovery of EVI and GPP, respectively. Our study underscores the significance of soil moisture and rainfall seasonality in influencing plant growth.

Source separation and anaerobic co-digestion of blackwater and food waste for biogas production and nutrient recovery.

Anaerobic co-digestion of source-separated blackwater (BW) and food and kitchen waste (FW) offers decentralized circular economy solutions by enabling local production of biogas and nutrient-rich byproducts. In this study, a 2 m3 pilot-scale continuously stirred tank reactor (CSTR) operated under mesophilic conditions was utilized for co-digestion of BW and FW. The process obtained a CH4 yield of 0.7 ± 0.2 m3/kg influent-volatile solid (VS), reaching a maximum yield of 1.1 ± 0.1 m3/kg influent-VS, with an average organic loading rate of 0.6 ± 0.1 kg-VS/m3/d and HRT of 25 days. The CH4 production rate averaged 0.4 ± 0.1 m3/m3/d, peaking at 0.6 ± 0.1 m3/m3/d. Treatment of digestate through flocculation followed by sedimentation recovered over 90% of ammonium nitrogen and potassium, and 80-85% of total phosphorus in the liquid fraction. This nutrient-rich liquid was used to cultivate Chlorella vulgaris, achieving a biomass concentration of 1.2 ± 0.1 g/L and 85 ± 3% and 78 ± 5% ammonium nitrogen and phosphorus removal efficiency, respectively. These findings not only highlight the feasibility of anaerobic co-digestion of source-separated BW and FW in local biogas production but also demonstrate the potential of microalgae cultivation as a sustainable approach to converting digestate into nutrient-rich algae biomass.

Towards carbon neutrality and circular economy: an innovative combination of enhanced biogas production and nutrient recovery from sludge dewatering liquor at a municipal wastewater treatment plant in Germany.

An innovative circular economy (CE) system was implemented at the wastewater treatment plant (WWTP) in Brunswick. The performance of the CE system was evaluated for 4 years: the thermal pressure hydrolysis enhanced the methane production by 18% and increased the digestate dewaterability by 14%. Refractory COD formed in thermal hydrolysis and increased the COD concentration in the WWTP effluent by 4 mg L-1 while still complying with the legal threshold. Struvite production reached high phosphorus recovery rates of >80% with a Mg:P molar ratio ≥0.8. Nitrogen was successfully recovered as ammonium sulfate with high recovery rates of 85-97%. The chemical analyses of secondary fertilizers showed a low pollutant content, posing low risks to soil and groundwater ecosystems. The total carbon footprint of the WWTP decreased due to enhanced biogas production, the recovery of renewable fertilizers and a further reduction of nitrous oxide emissions. Using green energy will be crucial to reach carbon neutrality for the entire WWTP.

Phosphorus and bioenergy recovery from anaerobic co-digestion of food waste and corn residues with digested sludge: effect of HRT and pre-treatment methods

AbstractOrganic wastes from the human ecosystem including food waste (FW), agricultural waste and digested sludge (DS) from wastewater treatment can be utilized as valuable materials in anaerobic co-digestion (AcoD) for the dual purpose of bioenergy production and phosphorus (P) recovery through a chemical precipitation process. In this study, AcoD using FW and corn residues (CS) with DS for simultaneous sustainable phosphate release and biogas production were investigated. Different hydraulic retention times (HRT) of 10, 20, and 30 days were investigated, and FW was grinded, while CS pre-treatment methods including physical (FWCS), chemical (FWCS-Chem), and thermal (FWCS-Temp) were considered. The substrates of FW and CS compositions were conducted with a total organic loading of 6 g volatile solids (VS)/L/d (5 FW/1 CS) with a carbon-to-nitrogen ratio (C/N) of 24. The results indicate that FWCS-Chem showed the highest cumulative biogas production simultaneously with P release at HRT 20 days with 7279 L/m3 and 29.67%, respectively. Moreover, the effluent from all digesters exhibited a Mg/P ratio above 1, suitable for struvite precipitation without an external Mg source. Accordingly, FW, FWCS, and FWCS-Chem achieved P recovery rates of 63.64%, 69.75%, and 70.19% at 20-day HRT, with corresponding P contents in solids of 9.45, 9.43, and 8.29%, respectively. These values are comparable to commercial phosphate fertilizer containing 8.80% P. Moreover, incinerating the precipitating solids offers high-quality P concentrations in solids of up to 15.52, 16.32, and 16.31%, respectively. Hence, 20-day HRT was found to be the optimal condition for FW, CS, and DS for anaerobic co-digestion, resulting in the highest biogas production, P release, and maximum financial return for P recovery. Graphical abstract Phosphorus and bioenergy recovery from anaerobic co-digestion of food waste and corn residues with digested sludge.

Stem recovery and harvesting productivity of two different harvesting systems in final felling of Pinus patula

ABSTRACT With the current demand of wood products and industrial requirements, plantation owners need to re-think ways in which harvesting is carried out and identify the most efficient harvesting system that also utilizes small diameter parts of stem per industry’s product specifications. This paper contributes to the discussion by comparing the harvesting productivity and stem recovery between conventional harvesting (CH) and integrated harvesting (IH) systems. CH is harvesting which does not necessarily align with the log dimensional requirements of the customer and only recovers logs with big diameters while IH is based on harvesting and sorting logs according to need in a single operation so that as much volume and value as possible of the stands is realized. The study was carried out at the Sao Hill Forest Plantation in the Southern Highlands of Tanzania. The harvested compartment was purposively selected and divided into IH and CH plots. A total of 39 trees were randomly selected to be harvested from each plot. The findings portray a significant difference in the stem recovery of 75% for IH and 60% for CH. CH had an average cutting productivity of 16 m3/h as compared to 14 m3/h for IH while skidding productivity was 15.3 m3/h and 24.9 m3/h for IH and CH, respectively. In this study, the IH system resulted in higher production in terms of volume recovered, meaning IH had a significant impact on the production and stem recovery of the standard stem-wood for use in different industries.

Unlocking the one-step recovery of solid S8 products through sulfur electro-oxidation in an acidic media

The recognized sulfur oxidation reaction (SOR) is performed in alkaline condition, and its main products of NaSx (x=1–4) are dissolvable, increasing chemical consumption to obtain solid Sx products by the multi-step recovery. Herein, the dopant of atomic carbon on MoS2 nanosheets (C-MoS2) was fabricated by chemical vapor deposition, and it can one-step convert H2S gas to solid S8 products in an acidic solution. Results showed that the yield of S8 product on C-MoS2 reached up to 2.5 kg/m2/d with a Faraday efficiency of 87.1 % at 20 mA/cm2. Moreover, theoretical and experimental studies proved that the electron density surrounding S active site increased with the incorporation of atomic C into MoS2, subsequently improving the adsorption energy of H2S and decreasing the reaction energy to obtain S8 product. Our work provides a new guideline for the SOR research on the one-step conversion of H2S to S8 solid products in acidic condition.

L-Ornithine derivatives with structural hetaryl and alkyl moiety: Synthesis and antibacterial activity

Objectives. Cationic amphiphiles and antimicrobial peptidomimetics are widely investigated as antibacterial agents due to their membrane-active mechanism of action. Particular attention is focused on the rational design of compounds in this class to achieve high antimicrobial activity. The aim of the present work is to synthesize bivalent cationic amphiphiles with L-ornithine as a branching element and evaluate the effectiveness of their antibacterial action. The compounds differ in terms of hydrophobicity due to the variation of N-terminal aliphatic amino acids in the polar block and alternation of dialkyl and alkyl-hetaryl radicals in the lipophilic block.Methods. For the synthesis of nonpolar fragments of amphiphiles, methods for the alkylation of amines with alkyl bromides in the presence of carbonate salts were used. The formation of amide bonds of L-ornithine derivatives with amino acids was carried out using the carbodiimide method. For the reaction products recovery from the reaction mixture, column chromatography on silica gel and aluminum oxide activated Brockmann Grade II was used. The antimicrobial activity of the synthesized compounds against gram-positive B. subtilis 534 and gram-negative E. coli M17 bacterial strains was evaluated. Minimum inhibitory concentration (MIC) values were recorded using a serial microdilution method in a nutrient medium.Results. Developed schemes for the preparation of bivalent cationic amphiphiles based on L-ornithine derivatives are presented. Differences in the structure of aliphatic amino acids (glycine, β-alanine, γ-aminobutyric acid (GABA)), in the length of alkyl radicals (C8, C12), or in the presence of an indole moiety, were used in the design of target compounds. The high antibacterial activity of the synthesized compounds was demonstrated. The most active compounds were lipoamino acids with terminal GABA residues and asymmetrical non-polar block (tryptamyl–dodecylamine). The MIC values were 0.39 μg/mL for gram-positive bacteria and 1.56 μg/mL for gram-negative bacteria. A GABA derivative with a symmetrical lipophilic moiety based on dioctylamine demonstrated activity with an MIC of 0.78 μg/mL against B. subtilis and 3.12 μg/mL against E. coli.Conclusions. Nine new lipoamino acid cationic bivalent amphiphiles based on L-ornithine were synthesized. The structure of the obtained compounds was confirmed by nuclear magnetic resonance 1H spectroscopy and mass spectrometry data. Leading compounds in antimicrobial activity against both gram-positive and gram-negative strains of bacteria were determined. The influence of the degree of lipophilicity in the asymmetric nonpolar block on the level of exhibited antimicrobial activity is demonstrated.

Biomining using microalgae to recover rare earth elements (REEs) from bauxite

Biomining using microalgae has emerged as a sustainable option to extract rare earth elements (REEs). This study aims to (i) explore the capability of REEs recovery from bauxite by microalgae, (ii) assess the change of biochemical function affected by bauxite, and (iii) investigate the effects of operating conditions (i.e., aeration rate, pH, hydraulic retention time) to REEs recovery. The results showed that increasing bauxite in microalgae culture increases REEs recovery in biomass and production of biochemical compounds (e.g., pigments and Ca-Mg ATPase enzyme) up to 10 %. The optimum pulp ratio of bauxite in the microalgae culture ranges from 0.2 % to 0.6 %. Chlorella vulgaris was the most promising, with two times higher in REEs recovery in biomass than the other species. REEs accumulated in microalgae biomass decreased with increasing pH in the culture. This study establishes a platform to make the scaling up of REEs biomining by microalgae plausible.

ANALYSIS AND CREATION OF NEW ENERGY-SAVING DESIGNS OF INSTALLATIONS FOR ENVIRONMENTALLY COMBUSTION OF LIQUID FUEL IN OIL FACTORY FURNACES USING THE HEAT OF OUTLET COMBUSTION PRODUCTS

The article analyzes the installations and methods used at oil refineries for recycling the heat of exhaust flue gases in order to increase the efficiency of fuel use in tube furnaces and accompanying reduction in pollutant emission into the air basin. Recommendations on rational type selection of waste heaters for furnace units of oil refining industries are given.The authors present fundamentally new installations for burning liquid fuel in the form of oil-water emulsions using the heat recovery of emitted combustion products of furnace installations for heating the oil-water emulsion and its further environmentally friendly combustion, i.e. reduction of harmful emissions. The proposedoriginal installations differ from well-known analogues in the novelty of their design, a fairly high environmental effect and relatively low material costs.

UV-based dynamic control improves the robustness of multicolumn countercurrent solvent gradient purification of oligonucleotides.

Therapeutic oligonucleotides (ONs) have great potential to treat many diseases due to their ability to regulate gene expression. However, the inefficiency of standard purification techniques to separate the target sequence from molecularly similar variants is hindering development of large scale ON manufacturing at a reasonable cost. Multicolumn Countercurrent Solvent Gradient Purification (MCSGP) is a valuable process able to bypass the purity-yield tradeoff typical of single-column operations, and hence to make the ON production more sustainable from both an economic and environmental point of view. However, operating close to the optimum of MCSGP can be challenging, resulting in unstable process performance and in a drift in product quality, especially when running a continuous process for extended periods where process parameters such as temperature are prone to variation. In this work, we demonstrate how greater process robustness is introduced in the design and execution of MCSGP for the purification of a 20mer single-stranded DNA sequence through the implementation of UV-based dynamic control. With this novel approach, the cyclic steady state was reached already in the third cycle and disturbances coming from fluctuations in the feed quality, loading amount and temperature were effectively compensated allowing a stable operation close to the optimum. In response to the perturbations, the controlled process kept the standard deviation on product recovery below 3.4%, while for the non-controlled process it increased up to 27.5%.

Enhanced hydrolysis of waste activated sludge and recovery of volatile fatty acids: Performance and mechanistic analysis of synergistic treatment with sodium citrate and calcium oxide

Anaerobic fermentation has emerged as a promising method of transforming waste activated sludge into high-value products (e.g., volatile fatty acids (VFAs)). This work developed sodium citrate (SC)-calcium oxide (CaO) pretreatment to accelerate the production of VFAs by enhancing sludge solubilization and disintegration of extracellular polymeric substances. The results showed that co-pretreatment with 0.25 g/g TSS of SC and 0.05 g/g TSS of CaO effectively boosted VFAs accumulation (5823.3 mg COD/L), which was 12.2 times higher than the Control group. SC-CaO pretreatment enhanced hydrolysis and acidogenesis by providing ample organic substrates, thereby promoting the growth of hydrolytic and acidogenic bacteria. Additionally, the fermentation broth resulting from co-pretreatment exhibited lower phosphorus concentration and higher biodegradability. Economic analysis confirmed that the combined pretreatment is cost-effective. This work provides a viable strategy for enhancing high-value product recovery from sludge.

Quality and Pricing Decisions in a Dual-Channel Closed-Loop Supply Chain Considering Imperfect Product Recycling

Level of quality not only affects demand but also affects the proportion of imperfect products and then affects profit. This paper takes the quality level as a decision variable, considers both the consumer demand and the recovery of imperfect products in a dual-channel closed-loop supply chain (CLSC), and studies the significance of a revenue-sharing contract for coordination. The results show that the relationship between the optimal price and the quality level is affected by the repair cost of imperfect products and that the consumer’s attention to price and quality affects the trend of the overall profit with the quality level. In some cases, simply improving the quality level cannot expand the demand and is not even conducive to the improvement of green supply chain profits. It is also found that in both centralized and decentralized scenarios, coordination contracts can effectively motivate retailers to collect waste and help improve the economic efficiency of green supply chains.

Innovation and investment activities in crop production in Kazakhstan based on the example of grain industry: modern approaches

Innovative and investment development of agro-industrial complex, based on modernization of technical equipment, introduction of digital technologies, and increase in investment flow, helps to increase labor productivity and create competitive products, which determined the relevance of the study. The goal is theoretical and methodological substantiation and development of practical recommendations for stimulating innovation and investment activity in crop production sector of the republic based on the example of grain subcomplex. Methods – study of statistical, economic information, systematic approach to identifying general trends and effects, graphical representation. Results – lack of modern agricultural machinery, insufficient level of modernization of rural infrastructure and access to the market, low degree of renewal of fixed assets of enterprises, wear and tear of machinery and equipment, limited influx of investments due to seasonality and high risks for investors have become the main obstacle to sustainable growth of the main indicators of this sector of economy. The authors conducted correlation analysis of the dynamics of investment in crop production and gross production, which was confirmed by strong positive relationship. Conclusions – by summarizing, the authors recommend increase investment capital in the use of environmental and green technologies, implementing training and consulting programs for farmers on advanced technologies and innovations in crop production farms, leasing financing, and partnerships with research institutes for the exchange of knowledge and experience. Joint research and experiments should become the main tools of state regulation of innovation and investment activities in agriculture in order to ensure the country's food security. Investments and innovations should be considered as a single system, on the successful functioning of which the economic recovery and stabilization of agricultural production depend.

An update on biotechnological intervention mediated by plant tissue culture to boost secondary metabolite production in medicinal and aromatic plants

AbstractSince prehistoric times, medicinal and aromatic plants (MAPs) have been employed for various therapeutic purposes due to their varied array of pharmaceutically relevant bioactive compounds, i.e. secondary metabolites. However, when secondary metabolites are isolated directly from MAPs, there is occasionally very poor yield and limited synthesis of secondary metabolites from particular tissues and certain developmental stages. Moreover, many MAPs species are in danger of extinction, especially those used in pharmaceuticals, as their natural populations are under pressure from overharvesting due to the excess demand for plant‐based herbal remedies. The extensive use of these metabolites in a number of industrial and pharmaceutical industries has prompted a call for more research into increasing the output via optimization of large‐scale production using plant tissue culture techniques. The potential of plant cells as sources of secondary metabolites can be exploited through a combination of product recovery technology research, targeted metabolite production, and in vitro culture establishment. The plant tissue culture approach provides low‐cost, sustainable, continuous, and viable secondary metabolite production that is not affected by geographic or climatic factors. This study covers recent advancements in the induction of medicinally relevant metabolites, as well as the conservation and propagation of plants by advanced tissue culture technologies.

Experimental Study on Edge Water Invasion of Strongly Heterogeneous Carbonate Gas Reservoirs Based on NMR Technology

Controlling the extent of water invasion in the reservoir and mitigating its detrimental effects on gas well production and natural gas recovery have long been a challenging task in the efficient development of strongly heterogeneous edge water gas reservoirs. To elucidate the edge water invasion mechanism of strongly heterogeneous carbonate gas reservoirs, this study investigates the pore throat characteristics and fluid mobility from both qualitative and quantitative aspects, leveraging natural core observations, cast thin sections, scanning electron microscopy (SEM), and nuclear magnetic resonance (NMR) tests with centrifuge experiments. A core-scale edge water invasion simulation experiment was conducted under online NMR monitoring to examine the dynamic gas production characteristics of the three types of reservoirs during the water invasion process and to elucidate the formation mechanism and distribution pattern of water-sealed gas. Research findings indicate that carbonate reservoirs typically exhibit a diverse range of pore types, including various types of fractures and cavities. Fractures significantly enhance reservoir connectivity, thereby increasing fluid mobility, but also lead to strong non-uniform water invasion. In contrast, cavities substantially improve the storage capacity of the reservoir and can retard the advancement of the water invasion front, thereby alleviating the adverse effects of water invasion. The ultimate recovery rates of fracture-type, cavity-type, and fracture-cavity cores in the water invasion simulation experiment were 29.81%, 64.87%, and 53.03%, respectively. Premature water breakthroughs in the reservoir can result in a large number of gases in matrix pores and even cavities being sealed by formation water, rendering them unrecoverable, which seriously impacts the gas recovery rate of the reservoir.

Improving Downstream Process Related Manufacturability Based on Protein Engineering—A Feasibility Study

ABSTRACTWhile bioactivity and a favorable safety profile for biotherapeutics is of utmost importance, manufacturability is also worth of consideration to ease the manufacturing process. Manufacturability in the scientific literature is mostly related to stability of formulated drug substances, with limited focus on downstream process‐related manufacturability, that is, how easily can a protein be purified. Process‐related impurities or biological impurities like viruses and host cell proteins (HCP) are present in the harvest which have mostly acid isoelectric points and need to be removed to ensure patient safety. Therefore, during molecule design, the surface charge of the target molecule should preferably differ sufficiently from the surface charge of the impurities to enable an efficient purification strategy. In this feasibility study, we evaluated the possibility of improving manufacturability by adapting the surface charge of the target protein. We generated several variants of a GLP1‐receptor‐agonist‐Fc‐domain‐FGF21‐fusion protein and demonstrated proof of concept exemplarily for an anion exchange chromatography step which then can be operated at high pH values with maximal product recovery allowing removal of HCP and viruses. Altering the surface charge distribution of biotherapeutic proteins can thus be useful allowing for an efficient manufacturing process for removing HCP and viruses, thereby reducing manufacturing costs.

A Mini Review on the Influence of Different Intermediate Mass Transfer Effects on the Chemical Pretreatment of Lignocellulosic Biomass

ABSTRACTChemical pretreatment of lignocellulosic biomass (LCB) in the presence of an alkaline catalyst is one of the major pretreatment processes that recover cellulose, hemicellulose, and lignin at effective process conditions and also for the production of bioethanol. Replacement of conventional catalysts with waste‐derived catalysts in the pretreatment process will be helpful for the development of low‐cost biorefinery. The continuous impact of different mass transfer properties during the chemical pretreatment of LCB will affect the final yield of products at a high reaction time and has been reviewed in the current study. Intraparticle diffusion of an alkaline catalyst into LCB is going to determine the diffusion of the selected catalyst within the porous biomass structure, which helps in the enhancement of the final yield of the product recovery at low‐process conditions. The diffusion of the synthesized catalyst within the selected biomass during the chemical pretreatment process is a rate‐limiting step that influences the final recovery yield of desired products. Enhancement of the biomass pretreatment reaction through the assessment of the diffusivity using the modified Nernst–Einstein relation is also discussed. Determination of different unique mass transfer properties rate of diffusion, diffusivity flux, and mass transfer coefficient are also to be analyzed to advance the reaction rate of the pretreatment process.

Factors, Mechanisms, and Kinetics of Spontaneous Emulsification for Heavy Oil-in-Water Emulsions.

In challenging reservoirs where thermal recovery falls short, cold or chemical oil recovery methods are crucial. Spontaneous emulsification (SE), triggered by gentle disturbance, significantly enhances oil recovery. In elucidating SE mechanisms and kinetics, SE processes via direct contact between oil and aqueous phases without stirring were conducted. The effects of temperature, emulsifier concentration, pH, NaCl concentration, and the oil-to-water ratio on SE were investigated through droplet size analysis and turbidity measurements. Furthermore, the emulsification mechanism and derived emulsification kinetics based on turbidity data were obtained. The results underscore the feasibility of SE for oil-water systems, reducing viscous and capillary resistances without agitation. The emulsified oil mass increased with the temperature, pH, and aqueous-to-oil phase volume ratio while decreasing with the NaCl concentration. In this study, for GD-2 crude oil, the optimal emulsified oil amount occurred at a betaine surfactant (BetS-2) emulsifier concentration of 0.45%. Microscopic photo analysis indicated narrow particle size distributions and small droplets, which remained stable over time under various experimental conditions. A combined SE mechanism involving ultralow interfacial tension, interfacial turbulence due to Marangoni effects, and "diffusion and stranding" due to in situ emulsifier hydrophilicity, was speculated. Additionally, an analogous second-order kinetic equation for SE was proposed, indicating exceptional correlation with calculated and experimentally measured values. This study offers theoretical insight for enhancing oil recovery in chemical and cold production of heavy oil in oilfields.

In-Sn alloy extraction through novel process for recycling of spent ITO targets

The feasibility of utilizing spent indium tin oxide (s-ITO) as an inert anode for the recovery of s-ITO targets through the electro-deoxidation was investigated, which concurrently achieved the avoidance of molten salt pollution caused by graphite anodes and maximized the utilization of resources by using the same material as the anode and cathode. Various techniques including anodic polarization and Tafel polarization were employed to evaluate the corrosion resistance and electrochemical stability of s-ITO. XRD and XPS are used to analyze the phase and valence state of the anodic materials and products, respectively. The practicability of replacing graphite anodes with s-ITO anodes was discussed in detail under identical electrolytic conditions. When using s-ITO as the anode, the carbon content and oxygen content in the electrolytic product are 31 ppm and 57 ppm, respectively, which are lower than those of graphite as the anode. Moreover, based on the results of above investigations, a cathode and anode collaborative electrolytic device was devised to maximize the utilization of resources and recovery of high-value products. The findings indicate that s-ITO has good corrosion resistance when used as an inert anode.