Cellulose Membranes in the Treatment of Spent Deep Eutectic Solvent Used in the Recovery of Lignin from Lignocellulosic Biomass

Ultrafiltration was employed in the purification of spent Deep Eutectic Solvent (DES, a mixture of choline chloride and lactic acid, 1:10, respectively) used in the extraction of lignin from lignocellulosic biomass. The aim of this was to recover different lignin fractions and to purify spent solvent. The results revealed that the commercial regenerated cellulose membranes—RC70PP and Ultracel 5 kDa UF membranes—could be used in the treatment of the spent DES. The addition of cosolvent (ethanol) to the spent DES decreased solvent’s viscosity, which enabled filtration. With two-pass ultrafiltration process with 10 kDa and 5 kDa membranes about 95% of the dissolved polymeric compounds (lignin and hemicelluloses) were removed from the spent DES. The utilized membranes also showed the capability to fractionate polymeric compounds into two fractions—above and under 10,000 Da. Moreover, the 10 kDa cellulose-based membrane showed good stability during a continuous period of three weeks exposure to the solution of DES and ethanol. Its pure water permeability decreased only by 3%. The results presented here demonstrate the possibility to utilize cellulose membranes in the treatment of spent DES to purify the solvent and recover the interesting compounds.

Application of the Ultrafiltration and Photooxidation Process for the Treatment of Rainwater

As water resources become increasingly scarce, the concept of water reuse is gaining importance. Recently, attention has been paid to the use of rainwater as an alternative water resource. Part of this study, laboratory-scale experiments were conducted to evaluate the effectiveness and efficiency of the ultrafiltration process. The aim of the research was to assess the influence of pollutants from various roof coverings on the ultrafiltration process and the occurrence of membrane fouling. Additionally, the rainwater disinfection process was performed using UV radiation. Analysis of rainwater collected from various roofing materials, evaluating rainwater treatment by ultrafiltration in a cross-flow system, determination of the effectiveness and efficiency of the UF membrane, and additional disinfection of rainwater using UV radiation were carried out. Rainwater was collected from various roofing materials, such as steel roof tiles (RW1), bituminous shingles (RW2), and tar paper roofing (RW3). The treatment efficiency of ultrafiltration was evaluated by monitoring typical quality parameters: color, turbidity, COD, TOC, absorbance of UV254, ammonium, conductivity, and pH. Coliform bacteria, Escherichia coli and Enterococci, were monitored as total number of microorganisms at 22 ± 2 °C after 72 h. As expected, a significant reduction in individual parameters was recorded. COD of rainwater decreased in RW1 by 59%, in RW2 by 69%, and in RW3 by 74%. The ultrafiltration process ensured the complete retention of the coliform bacteria and E. coli. Complete elimination of microorganisms was demonstrated when the ultrafiltration process and UV radiation disinfection were combined.

Bioactive and Physicochemical Characteristics of Natural Food: Palmyra Palm (Borassus flabellifer Linn.) Syrup

Palmyra palm syrup, produced from Borassus flabellifer flowers’ sap, is rich in nutrients and minerals and has unique flavors. This study evaluated the in vitro antioxidant activity, physicochemical characteristics, and Maillard reaction products of palmyra palm syrup prepared by thermal and ultrafiltration processes. Palmyra palm syrup prepared by a thermal process had smaller L*, b* values, and larger a* values than that prepared by an ultrafiltration process. Palmyra palm syrup contained 10 vitamins, the most abundant being vitamin E. Overall, 38 volatile compounds were found and classified into six groups in the order of alcohols > acids > ketones > sulfurs > pyrazines > phenols and aldehyde. Volatile compounds depended on concentration, temperature, and ultrafiltration process. Protein content decreased because of participation in the Maillard reaction and increased 5-hydroxymethylfurfural (HMF) and total phenolic content. The HMF content was very low (0.02–14.95 mg/100 g). The radical scavenging activity of 2,2-diphenyl-1-1 picrylhydrazyl and 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) in palmyra palm syrup with thermal process was higher than with ultrafiltration. This study established that ultrafiltration pretreatment of palmyra palm syrup generated a good appearance and reduced the HMF content, however, it negatively affected the volatile compounds and physicochemical characteristics.

Features of ultrafiltration of milk obtained from cows with CSN3 polymorphism

Мембранные процессы широко внедрены на современных предприятиях молочной промышленности, поскольку они способствуют обеспечению максимальной степени использования сырья и повышению качества готовой продукции. При этом они без затруднений интегрируются в классическую технологическую цепочку. Научные изыскания, направленные на дальнейшее совершенствование технологий баромембранного концентрирования молочного сырья, а также использование генетического подхода к формированию его технологических свойств весьма актуальны. Целью данной работы являлось исследование закономерностей процесса ультрафильтрации обезжиренного молока, полученного из молока коров с генотипами АА и ВВ по гену CSN3. Объектом исследований служило обезжиренное молоко, полученное из молока от КРС черно-пестрой породы с гомозиготными генотипами по гену CSN3 (АА и ВВ). Концентрирование молока осуществляли на пилотной установке с полиэфирсульфоновыми мембранами с порогом задержки по молекулярной массе 50 кДа при температуре 15…20 °С и объемном факторе концентрирования 3,5. В результате исследований выявлена закономерность снижения скорости процесса ультрафильтрации вследствие большей эффективности концентрирования массовых долей белка и сухих веществ обезжиренного молока, полученного из молока коров с генотипом АА по гену CSN3, по отношению к молоку от коров с генотипом ВВ. Membrane processes are widely used in modern dairy production, as they help to maximize the use of raw materials and improve the quality of end product. At the same time, they are easily integrated into the classical technological chain. Further improvement of the baromembrane concentration of dairy raw products technologies and the use of the genetic approach to the formation of its technological properties is an urgent scientific study today. The aim of this work was to study the regularities of the ultrafiltration process of skim milk obtained from the milk of cows with genotypes AA and BB according to the CSN3 gene. The object of research was skim milk obtained from milk from black-and-white cattle with homozygous genotypes for the CSN3 gene (AA and BB). Milk concentration was carried out on a pilot plant with polyethersulfone membranes with a retention threshold in molecular weight of 50 kDa at a temperature of 15…20 °C and a volumetric concentration factor of 3.5. As a result of the research, a regularity of the decrease in the rate of the ultrafiltration process was revealed due to the greater efficiency of concentration of mass fractions of protein and dry matter of skim milk obtained from milk of cows with the AA genotype according to the CSN3 gene in relation to milk from cows with the BB genotype.