Optimization of enzymatic hydrolysis of triglycerides in soy deodorized distillate with supercritical carbon dioxide

Removal of metals and inorganics from rendered fat using polyamine-modified cellulose nanocrystals

Meatpacking and poultry operations produce an enormous amount of co-products including offal, fat, blood, feathers etc. that are collected and processed by the rendering industry into value-added materials such as various protein meals and rendered fat products. Rendered fats (mainly composed of triglycerides from the adipose tissue of animals or used cooking oil from the restaurant industry) are sold for a variety of applications including animal feed formulations. Nonetheless, in the current context of energy scarcity, their use as feedstocks for the generation of renewable fuels including biodiesel and renewable diesel represents a growing market. The diverse composition of the source material can impose significant challenges in terms of compliance, requiring the control (and reduction) of the concentration of elements such as phosphorus, sulfur, calcium, magnesium, sodium, potassium, and other undesirable metals that can otherwise interfere with critical aspects of the refining process or contaminate the renewable fuel products. To address this critical need, we describe the application of poly(ethylenimine)-modified cellulose nanocrystals as a low-cost material for the removal of unwanted metal/inorganic cations from rendered fat. A total of 28 real samples including poultry, white pork grease, and beef tallow were analyzed. Test results showed that the approach can effectively decrease the concentration of the target elements by 95 ± 2%, suggesting that this treatment protocol could dramatically improve the application of rendered fat products for renewable fuel refining.

A review on polysaccharides from Artemisia sphaerocephala Krasch seeds, their extraction, modification, structure, and applications

Artemisia sphaerocephala Krasch (ASK) is an important member of Compositae (Asteraceae) family. Its seeds have been widely used as traditional medicine and to improve the quality of food. Water soluble and water insoluble polysaccharides are found in the seeds of this plant. Research has been conducted on the extraction of polysaccharides, their modification and determination of their structure. To date different techniques for extraction purposes have been applied which are reviewed here. Antioxidant, antidiabetic, anti-obesogenic, antitumor, and immunomodulatory activities have been explored using in vivo and in vitro methods. Moreover, these polysaccharides have been used as packaging material and as a sensing component for monitoring the freshness of packaged food. Some experimental results have shown that the quality of foods is also improved by using them as a food additive. We have also indicated some of the potential areas that are needed to be explored.

CO2 -Enabled Biomass Fractionation/Depolymerization: A Highly Versatile Pre-Step for Downstream Processing

Lignocellulosic biomass is inevitably subject to fractionation and depolymerization processes for enhanced selectivity toward specific products, in most cases prior to catalytic upgrading of the three main fractions-cellulose, hemicellulose, and lignin. Among the developed pretreatment techniques, CO₂ -assisted biomass processing exhibits some unique advantages such as the lowest critical temperature (31.0 °C) with moderate critical pressure, low cost, nontoxicity, nonflammability, ready availability, and the addition of acidity, alongside easy recovery by pressure release. This Review showcases progress in the study of sub- or supercritical CO₂ -mediated thermal processing of lignocellulosic biomass-the key pre-step for downstream conversion processes. The auxo-action of CO₂ in biomass pretreatment and fractionation, along with the involved variables, direct degradation of untreated biomass in CO₂ by gasification, pyrolysis, and liquefaction with relevant conversion mechanisms, and CO₂ -enabled depolymerization of lignocellulosic fractions with representative reaction pathways are summarized. Moreover, future prospects for the practical application of CO₂ -assisted up- and downstream biomass-to-bioproduct conversion are also briefly discussed.

Green Technologies for the Production of Modified Lipids

In recent years, the use of green solvents in enzyme catalysis of lipophilic compounds is achieving increasing interest from different perspectives. Conducting reactions under supercritical fluids, ionic liquids, deep eutectic solvents, and other green solvents affords opportunities to overcome problems associated with the lack of solubility of lipids in conventional solvents and the poor miscibility of substrates. Research on the biocatalytic production of modified lipids in the framework of green chemistry is conducted to improve the efficiency of obtaining the desired products as well as the selectivity, stability, and activity of the enzymatic systems. This overview describes the fundamentals and characteristics of several types of green solvents, the main variables involved in enzymatic processes, and examples and applications in the field of lipid modification.

Efficient stripping of photoresist on metallized wafers by a pause flow of supercritical fluid

Utilization of supercritical fluids (SCFs) is studied here on the premises of a saving of hazardous organic solvents and of the specification for stripping the photoresist (PR) on metallization layers, which is one of the integrated circuit processing modules. By using factorial experimental designs with five factors and four level ranges, this research focuses on determining an optimized recipe with high stripping efficiency and to determine the stripping mechanism. In the case of PR on an aluminum layer, the initial use of the pulse flow mode could increase the extraction ratio remarkably when compared to the conventional continuous flow mode. Based on the limitation of a total volume of 30 mL purging SCF-CO(2) for economical considerations, the optimum conditions can be summarized as follows: 120 degrees C, oven temperature; 350 atm, CO(2) pressure; 0.2 mL of ethylacetate spiking to SCF-CO(2); 2.0 min, static equilibrium time; and five cycles of dynamic flow pausing. A recovery of 94.6% (n=3, RSD=6.5%) was obtained, while the diffusion of stripped PR from substrate matrix prevailed over the dissolution of binding PR into the SCF medium. In the case of copper, the optimum parameters in a pause flow mode were 140 degrees C, oven temperature; 500 atm, CO(2) pressure; 0.75 mL, ethylacetate spiking volume; 5.0 min, static time; and six cycles of flow pausing. These extreme parameters still did not produce an SCF environment suitable for diffusion or dissolution mass transfer, and thus a recovery of 76.2% (n=3, RSD=7.5%) was only obtained. Removing PR coated on a Cu layer was harder than that on an Al layer.