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Bridging the gap between theory and practice, this text provides the reader with a comprehensive overview of industrial crystallization. Newcomers will learn all of the most important topics in industrial crystallization, from key concepts and basic theory to industrial practices. Topics covered include the characterization of a crystalline product and the basic process design for crystallization, as well as batch crystallization, measurement techniques, and details on precipitation, melt crystallization and polymorphism. Each chapter begins with an introduction explaining the importance of the topic, and is supported by homework problems and worked examples. Real world case studies are also provided, as well as new industry-relevant information, making this is an ideal resource for industry practitioners, students, and researchers in the fields of industrial crystallization, separation processes, particle synthesis, and particle technology.

BackgroundMultidrug resistant microorganisms are a growing challenge and new substances that can be useful to treat infections due to these microorganisms are needed. Silver nanoparticle may be a future option for treatment of these infections, however, the methods described in vitro to evaluate the inhibitory effect are controversial.ResultsThis study evaluated the in vitro activity of silver nanoparticles against 36 susceptible and 54 multidrug resistant Gram-positive and Gram-negative bacteria from clinical sources. The multidrug resistant bacteria were oxacilin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus spp., carbapenem- and polymyxin B-resistant A. baumannii, carbapenem-resistant P. aeruginosa and carbapenem-resistant Enterobacteriaceae. We analyzed silver nanoparticles stabilized with citrate, chitosan and polyvinyl alcohol and commercial silver nanoparticle. Silver sulfadiazine and silver nitrate were used as control. Different methods were used: agar diffusion, minimum inhibitory concentration, minimum bactericidal concentration and time-kill. The activity of AgNPs using diffusion in solid media and the MIC methods showed similar effect against MDR and antimicrobial-susceptible isolates, with a higher effect against Gram-negative isolates. The better results were achieved with citrate and chitosan silver nanoparticle, both with MIC90 of 6.75 μg mL−1, which can be due the lower stability of these particles and, consequently, release of Ag+ ions as revealed by X-ray diffraction (XRD). The bactericidal effect was higher against antimicrobial-susceptible bacteria.ConclusionIt seems that agar diffusion method can be used as screening test, minimum inhibitory concentration/minimum bactericidal concentration and time kill showed to be useful methods. The activity of commercial silver nanoparticle and silver controls did not exceed the activity of the citrate and chitosan silver nanoparticles. The in vitro inhibitory effect was stronger against Gram-negative than Gram-positive, and similar against multidrug resistant and susceptible bacteria, with best result achieved using citrate and chitosan silver nanoparticles. The bactericidal effect of silver nanoparticle may, in the future, be translated into important therapeutic and clinical options, especially considering the shortage of new antimicrobials against the emerging antimicrobial resistant microorganisms, in particular against Gram-negative bacteria.

Bacterial cellulose (BC) is used in different fields as a biological material due to its unique properties. Despite there being many BC applications, there still remain many problems associated with bioprocess technology, such as increasing productivity and decreasing production cost. New technologies that use waste from the food industry as raw materials for culture media promote economic advantages because they reduce environmental pollution and stimulate new research for science sustainability. For this reason, BC production requires optimized conditions to increase its application. The main objective of this study was to evaluate BC production by Gluconacetobacter xylinus using industry waste, namely, rotten fruits and milk whey, as culture media. Furthermore, the structure of BC produced at different conditions was also determined. The culture media employed in this study were composed of rotten fruit collected from the disposal of free markets, milk whey from a local industrial disposal, and their combination, and Hestrin and Schramm media was used as standard culture media. Although all culture media studied produced BC, the highest BC yield-60 mg/mL-was achieved with the rotten fruit culture. Thus, the results showed that rotten fruit can be used for BC production. This culture media can be considered as a profitable alternative to generate high-value products. In addition, it combines environmental concern with sustainable processes that can promote also the reduction of production cost.

Crystallization and precipitation from solutions are responsible for 70% of all solid materials produced by the chemical industry. Competing with distillation as a separation and purification technique, their use is widespread. They operate at low temperatures with low energy consumption and yield with high purifications in one single step. Operational conditions largely determine product quality in terms of purity, filterability, flowability and reactivity. Producing a material with the desired quality often requires a sound knowledge of the elementary steps involved in the process: creation of supersaturation, nucleation, crystal growth, aggregation and other secondary processes. Mathematical models coupling these elementary processes to all particles in a crystallizer have been developed to design and optimize crystallizer operation. For precipitation, the spatial distribution of reactants and particles in the reactor is important; thus the tools of computational fluid dynamics are becoming increasingly important. For crystallization of organic chemicals, where incorporation of impurities and crystal shape are critical, molecular modeling has recently appeared as a useful tool. These theoretical developments must be coupled to experimental data specific to each material. Theories and experimental techniques of industrial crystallization and precipitation from solutions are reviewed, and recent developments are highlighted

Solubilities in the system sodium carbonate + sodium bicarbonate were measured over a range of temperatures from (50 to 90) °C in mixed aqueous solvents containing (50 to 100) mass % (salt-free solvent) ethylene glycol. Mixtures of solid sodium carbonate anhydrate (Na2CO3(s)) and solid sodium bicarbonate (NaHCO3(s)) in different ratios and also trona (Na2CO3·NaHCO3·2H2O(s)) were allowed to recrystallize and equilibrate with the mixed solvents at the given temperatures. The solubility of CO3 2- was generally found to decrease with increasing ethylene glycol content irrespective of the occurring solid phase, while HCO3 - solubility displayed a minimum at (80 to 90) mass % (salt-free solvent) ethylene glycol and then increased sharply. For pure carbonate phases, CO3 2- solubility displayed little temperature dependence. In equilibrium with mixed carbonate−bicarbonate phases, the CO3 2- solubility usually decreased with temperature, most likely because it was linked to the HCO3 - concentration via the solid's solubility product. The solubility of HCO3 - increased significantly with temperature for all sodium bicarbonate containing solid phases. For the temperature range from (30 to 90) °C and an ethylene glycol concentration range of (50 to 100) mass % (of salt-free solvent), the CO3 2- solubility varied between (0.058 and 1.023) mol/kg solution, and the HCO3 - solubility concentration ranged between 0.000 (i.e. the lower detection limit of the analytical method) and 1.153 mol/kg solution. The occurring solid phases were the same as those formed in the aqueous system. They were identified in the recrystallization experiments as sodium carbonate anhydrate (Na2CO3(s)), sodium carbonate monohydrate (Na2CO3·H2O(s)), trona (Na2CO3·NaHCO3·2H2O(s)), wegscheiderite (Na2CO3·3NaHCO3(s)), and sodium bicarbonate (NaHCO3(s)). No solvate phases with ethylene glycol were observed.

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-An organic-mineral fertilizer based on humic substances (HSs) and potassium was developed based on the alkaline extraction of HSs from peat. The HSs have interesting properties for use as a fertilizer since they improve the physical and chemical structure of the soil and provide a source of organic carbon which is readily absorbable by the plants, whereas potassium is a primary nutrient for plants. It was found that highly decomposed peats containing a small inorganic fraction are more favorable for the extraction of HSs. Using these peats, organic-mineral fertilizers that meet the Brazilian legislation have been obtained for a peatextractant mixture containing 2.57 wt% total organic content (TOC), a K 2 O/TOC ratio of 1 wt% and an extraction time of 12 hours.