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Members of the IQ Consortium ″Working Group on Characterization on Amorphous Solid Dispersions″ shares here a perspective on the analytical challenges, and limitations of detecting low levels of crystalline drug substance in amorphous solid dispersions (ASDs) and associated drug products. These companies aim to employ highly sensitive commercially available analytical technologies to guide development, support control strategies, and enable registration of quality products. We hope to promote consistency in development and registration approaches and guide the industry in development of "characterization best practices" in the interest of providing high quality products for patients. The first half of this perspective highlights the unique challenges of analytical methodologies to monitor crystalline drug substance in ASDs and their associated drug products. Challenges around use of limit tests, analyte spiking experiments, and method robustness are also underscored. The latter half describes the merits and limitations of the diverse analytical "toolbox" (such as XRPD, NIR and DSC), which can be readily applied during development and, in some cases, considered for potential application and validation in the commercial QC setting when necessary.

Crystallized nanocellulose (CNC) was separated from paper-mulberry (Broussonetia kazinoki Siebold) bast pulp by sulfuric acid hydrolysis method and they were blended with agar to prepare bionanocomposite films. The effect of CNC content (1, 3, 5 and 10 wt% based on agar) on the mechanical, water vapor permeability (WVP), and thermal properties of the nanocomposites were studied. Changes of the cellulose fibers in structure, morphology, crystallinity, and thermal properties of the films were evaluated using FT-IR, TEM, SEM, XRD, and TGA analysis methods. The CNC was composed of fibrous and spherical or elliptic granules of nano-cellulose with sizes of 50-60 nm. Properties of agar film such as mechanical and water vapor barrier properties were improved significantly (p

Boric acid is known to be difficult to immobilize because it has a pKa of 9.23, which means it is present in a molecular form in most aqueous environments and can be changed in the structure and nature with the change of the environmental conditions. Layered double hydroxides (LDHs) are potential sorbents for borate. However, the drawbacks of using LDHs for borate removal are that they are affected by the presence of other anions and are difficult to separate from water. In the present work, novel composites of Mg–Al type of LDH, synthesized onto filter papers and then intercalated with gluconate (F-LDH-G) were prepared. LDH with interlayer of carbonate form was first immobilized onto the surface of filter paper (F-LDH-CO3) by in situ hydrothermal crystallization, and then ion-exchanged sequentially with chloride (F-LDH-Cl) followed by gluconate. The influence of the molar ratio of gluconate/LDH and reaction time on F-LDH-G synthesis was explored. Products were characterized by X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy and nuclear magnetic resonance as well as measurements of borate sorption. The optimal molar ratio of gluconate/LDH and reaction time for preparing F-LDH-G from F-LDH-Cl were 40 and 24 h (F-LDH-G-40–24 h), respectively. F-LDH-G-40–24 h had higher sorption density and greater stability than both the original filter paper and the filter papers containing other LDHs, even in the presence of other anions. 11B NMR and XRD results indicate that the principal mechanism for borate immobilization on F-LDH-G-40–24 h is complexation of gluconate with borate in both bischelate and monodentate forms. The novel composite is boron-specific and facilitates solid/liquid separation.

Material conversion from paper sludge ash (PSA) in NaOH solution was attempted to synthesize the adsorbent for removal of inorganic pollutants, such as Pb2+, NH4+ and PO4(3-) from aqueous solution. PSA of 0.5 g was added into 10 mL of 3 mol/L NaOH solution, and then heated at 80, 120, and 160 degrees C for 6-48 hr to obtain the product. PSA mainly composed of two crystalline phases, gehlenite (Ca2Al2SiO7) and anorthite (CaAl2Si2O8), and amorphous phase. Hydroxysodalite (Na6Al6Si6O24 8H2O) was formed at 80 degrees C, and anorthite dissolved, whereas gehlenite remained unaffected. Katoite (Ca3Al2SiO4(OH)8) was formed over 120 degrees C, and hydroxycancrinite (Na8(OH)2Al6Si6O24 2H2O) was formed at 160 degrees C, due to the dissolution of both gehlenite and anorthite. Specific surface areas of the products were almost same and were higher than that of raw ash. Cation exchange capacities (CECs) of the products were also higher than that of raw ash, and CEC obtained at lower temperature was higher. Removal abilities of products for Pb2+, NH4+, and PO4(3-) were higher than that of raw ash. With increasing reaction temperature, the removal efficiencies of Pb2+ and NH4+ decreased due to the decrease of CEC of the product, while removal efficiency for PO4(3-) was almost same. The concentrations of Si and Al in the solution and the crystalline phases in the solid during the reaction explain the formation of the product phases at each temperature.

Paper sludge ash was partially converted into zeolites by reaction with 3M NaOH solution at 90 degrees C for 24 h. The paper sludge ash had a low abundance of Si and significant Ca content, due to the presence of calcite that was used as a paper filler. Diatomite was added to the NaOH solution to increase its Si content in order to synthesize zeolites with high cation exchange capacity. Diatomite residue was filtered from solution before addition of ash. The original ash without addition of diatomite yielded hydroxysodalite with a cation exchange capacity ca. 50 cmol/kg. Addition of Si to the solution yielded Na-P1 (zeolite-P) with a higher cation exchange capacity (ca. 130 cmol/kg). The observed concentrations of Si and Al in the solution during the reaction explain the crystallization of these two phases. The reaction products were tested for their capacity for PO(4)(3-) removal from solution as a function of Ca(2+) content, suggesting the formation of an insoluble Ca-phosphate salt. The product with Na-P1 exhibits the ability to remove NH(4)(+) as well as PO(4)(3-) from solution in concentrations sufficient for application in water purification. Both NH(4)(+) and PO(4)(3-) removal showed little variation with pH between 5 and 9. Alternative processing methods of zeolite synthesis, including the addition of ash to an unfiltered Si-NaOH solution and addition of a dry ash/diatomite mixture to NaOH solution, were tested. The third process yielded materials with lower cation exchange capacity due to formation of hydroxysodalite. The second process results in a product with relatively high cation exchange capacity, and reduces the number of processing steps necessary for zeolite synthesis.

The authors of the title paper (Optics & Laser Tech 88 (2017) 147–151) claim to have grown a so-called inorganic nonlinear optical zinc di-magnesium chloro sulphate (ZDMCS) single crystal formulated as Zn 2(MgCl2) SO4. A critical analysis of the title paper is presented to show that the reported experimental data are not in agreement with the proposed formula of ZDMCS. In this letter to Editor, we prove that ZDMCS is in fact, the well-known crystal magnesium sulphate hexahydrate having formula MgSO4·6H2O.

Solid-state shear pulverization (SSSP) is a continuous process that overcomes challenges in producing well-dispersed polymer composites that cannot be made by twin-screw melt extrusion. We use SSSP to produce 85/15 wt% polypropylene/waste paper biocomposites with polypropylene pellets and 2-cm-square waste paper pieces as starting material. Single-pass SSSP achieves effective filler size reduction and dispersion within the polypropylene matrix. We determine how waste paper size reduction and composite properties are functions of specific energy input and tune specific energy input by SSSP screw design and throughput. Composites made at moderate to high specific energy input (14–35 kJ/g) have 25 to nearly 50% of filler particles at sub-micron size; relative to neat polypropylene, composites exhibit a 70% increase in Young’s modulus, retention of neat polypropylene yield strength, and a ∼50% reduction in crystallization half-time. Estimates indicate that the cost of such biocomposite materials made by SSSP is less than that of virgin polypropylene.

Xuan-paper waste residue (XPWR) is an unfamiliar and unique solid waste in China, which caused serious environmental pollution and waste of resources. Therefore, it is extremely important to explore the characteristics of XPWR and its application. In this paper, XPWR was analyzed and used as a reinforcing filler to prepare red mud/waste polyethylene/Xuan-paper waste residue (RM/WPE/XPWR) composites by molding method at 160 °C with a pressure of 10 MPa for 5-10 min. There were about 27 wt% of mineral particles and 63 wt% of organic fibers in XPWR, indicating that XPWR can be used as a reinforcing filler. When 60 wt% of XPWR was added in RM/WPE, the bending strength reached 71.81 MPa, which surpassed 43.08 % than that of RM/WPE. Besides, the addition of XPWR increased the water absorption of the composites and helped to promote the crystallization of the composites. This work presented the characteristics of XPWR and provided a new way to use XPWR.

Glass-ceramics were prepared from mixtures of wastes generated from refining of silica sand and kaolin clay (Kira) and paper sludge ash. Kira and paper sludge ash were mixed in mass ratios of 55/45. The mixtures were melted at 1400 °C and quenched in water to obtain glasses. The quenched glasses were ground to

The effect of heat treatment on the structure, piezoelectricity and actuation behavior of cellulose electroactive-paper actuators was studied by infrared spectroscopy, piezoelectricity measurement and the tip displacement test. After heat treatment at 60 °C for 2 h, the piezoelectric coefficient ( d 31 ) was enhanced nearly 10-fold as compared to that of non-heat-treated films. However, when the treatment temperature was raised above 60 °C the piezoelectric coefficients were higher than the non-treated film but lower than that of film treated at 60 °C. Infrared and UV–visible spectroscopy suggested that there were changes in chemical structure at higher treatment temperatures. Furthermore, the tip displacement tests performed on the actuators also showed almost same trend as that of the piezoelectric constant.

Solvent influences on the crystallization of polymorph and hydrate forms of the nootropic drug piracetam (2-oxo-pyrrolidineacetamide) were investigated from water, methanol, 2-propanol, isobutanol, and nitromethane. Crystal growth profiles of piracetam polymorphs were constructed using time-resolved diffraction snapshots collected for each solvent system. Measurements were performed by in situ energy dispersive X-ray diffraction recorded in Station 16.4 at the synchrotron radiation source (SRS) at Daresbury Laboratory, CCLRC UK. Crystallizations from methanol, 2-propanol, isobutanol, and nitromethane progressed in a similar fashion with the initial formation of form I which then converted relatively quickly to form II with form III being generated upon further cooling. However, considerable differences were observed for the polymorphs lifetime and both the rate and temperature of conversion using the different solvents. The thermodynamically unstable form I was kinetically favored in isobutanol and nitromethane where traces of this polymorph were observed below 10°C. In contrast, the transformation of form II and subsequent growth of form III were inhibited in 2-propanol and nitromethane solutions. Aqueous solutions produced hydrate forms of piracetam which are different from the reported monohydrate; this crystallization evolved through successive generation of transient structures which transformed upon exchange of intramolecular water between the liquid and crystalline phases.

Structure development in PET film during high strain-rate, constant-force (CF) deformation in the temperature range 80–96°C is compared with structure development during lower strain rate, constant-extension-rate (CER) deformation in a similar temperature range. The higher (maximum) strain rates involved in CF drawing mean that much of the deformation takes place in a regime where the time available for orientational relaxation and crystallization is short. This results in high levels of `non-crystalline orientation' and low levels of crystallinity compared to structures obtained from CER drawing. In CER drawing, due to the lower strain rates, the degree of crystallinity always has time to reach pseudo-equilibrium values corresponding to a given level of non-crystalline orientation, and the amount of orientational relaxation occurring during drawing has the dominant influence on structure development. In CF drawing, pseudo-equilibrium crystallinity values are not reached, except when the deformation approaches the tail-end of the strain-rate spectrum. The results also provide confirmation that microstructure data obtained from rapidly quenched samples are consistent with microstructure data obtained from real-time experiments.

An improved antibody-coated sensor system based on quartz crystal microbalance analysis on Salmonella spp. was developed making use of thiolated antibody immobilization onto one gold electrode of the piezoelectric quartz crystal surface. The best results in sensitivity and stability were obtained with the thin layer of a thiol-cleavable, heterobifunctional cross-linker, sulfosuccinimidyl 6-[3-(2-pyridyldithio)propionamido]hexanoate (sulfo-LC-SPDP). The long bridge of this reagent could function as a spacer, facilitating antibody-Salmonella interaction on the gold electrode. After the addition of a S. typhimurium suspension into a reaction cell with 0.1 M sodium phosphate buffer, pH 7.2, the resonant frequency decreased conspicuously. The time required for maximum frequency shift was about 30-90 min. Sensor response was observed for the microbial suspensions ranging from 9.9 x 10(5) to 1.8 x 10(8) CFU/ml.

In this article, Feng et al reply to a brief commentary on their recent study (Feng et al, 2004) on the pozzolanic properties of rice husk ash by hydrochloric acid pretreatment. In the study, the heat evolution and the hydration heat of cement, the Ca(OH)2 content in the mortar and the pore size distribution of mortar were determined. The results showed that pozzolanic activity of rice husk ash (RHA) is not only stabilized but also enhanced by pretreatment. In the commentary, Demirbas noted that the very high surface area of RHA increases its pozzolanic activity to compete with those of much finer admixtures. Demirbas called for additional attention on the chemical effects of pozzolanic materials on crystal formation during the hydration. Demirbas also referred readers to another study in which the pozzolanic properties of hydrochloric acid-treated RHA were systematically investigated (Yalcin and Sevinc, 2001). In their reply, the study authors agree with the comment that the chemical effects of pozzolanic materials on crystal formation and development during hydration should be expanded. The authors also provide some additional details regarding the pore distribution of rice husk ashes. They conclude by stressing that many more studies of this agricultural waste material need to be carried out.

The R F values of six cobalt (III) complexes in Iutanol/HCl, butanol/NH 3 , butanol/acetic acid, acetone-HCl and water were measured. In organic solvents the least iomyed complex travels fastest unless decomposed. In water the highly ionized complexes travel faster than the monovalent or neutral complexes.

This brief commentary discusses a recent study (Feng et al, 2004) on the pozzolanic properties of rice husk ash by hydrochloric acid pretreatment. In the study, the heat evolution and the hydration heat of cement, the Ca(OH)2 content in the mortar and the pore size distribution of mortar were determined. The results showed that pozzolanic activity of rice husk ash (RHA) is not only stabilized but also enhanced by pretreatment. In this commentary, Demirbas notes that the very high surface area of RHA increases its pozzolanic activity to compete with those of much finer admixtures. Demirbas calls for additional attention on the chemical effects of pozzolanic materials on crystal formation during the hydration. Demirbas also refers readers to another study in which the pozzolanic properties of hydrochloric acid-treated RHA were systematically investigated (Yalcin and Sevinc, 2001).

Under anhydrous conditions magnesian olivine and not orthopyroxene is on the liquidus in the primary basalt magmas after “magma separation” within the upper mantle which probably consists of olivine-rich lherzolite. The experiments carried out by Green and Ringwood (1967) on some primary basalt compositions in the pressure range in which orthopyroxene is on the liquidus would not be applicable to the fractional crystallization of the primary basalt magmas after “magma separation”. Under hydrous conditions, the field of orthopyroxene crystallization relative to that of magnesian olivine is reduced at higher pressures when the bulk chemical composition is kept constant. The possibility that silica-saturated magmas are formed increases under hydrous conditions, even if the water pressure is less than the total pressure. Green's suggestion, based on experiments with unsealed capsules, that the generation of olivine nephelinite and of olivine melilite nephelinite magmas under hydrous conditions would not be valid when the bulk chemical composition is kept constant.

In China, the most commonly used method for the synthesis of ibuprofen is aryl-1,2–translocation rearrangement, which comprises several main processes: the Friedel-hydrolysis reaction, ketal reaction and so on. There are some problems in the process of industrial production. The temperature control of the Friedel-hydrolysis reaction is a problem because excessive temperatures will lead to the occurrence of side reactions, and low temperatures will lead to the crystallization of raw reaction materials. The reaction time of the ketal reaction is up to 24 h, which limits the productive capacity of ibuprofen. Otherwise, the emissions of the ibuprofen synthesis processes are more than 5000 m3/h of waste gas with VOC contents of over 1000 mg/m3 and highly concentrated organic wastewater, with a COD up to 20,000 mg/L. Therefore, process intensification and waste minimization of the ibuprofen synthesis process is described in this paper. A new reactor is designed for the Friedel-hydrolysis reaction. The reaction temperature can be precisely controlled at 13–15 °C, which effectively inhibits the occurrence of side reactions. The industrial applications showed that the ketal reaction time is reduced from 24 h to less than 8 h. The VOC content is reduced to less than 100 mg/m3, and the COD value is reduced to 150 mg/L in the improved processes, which meet national emissions standards.

Inefficient separation of inorganic salts and organic matters in crystallization mother liquor is still a problem to industrial wastewater treatment since the high salinity significantly impedes organic pollutant degradation by oxidation or incineration. In the study, acidification combined electrodialysis (ED) was attempted to effectively separate Cl− ions from organics in concentrate pulping wastewater. Membrane's rejection rate to total organic carbon (TOC) was 85% at wastewater intrinsic pH = 9.8 and enhanced to 93% by acidifying it to pH = 2 in ED process. Negative-charged alkaline organic compounds (mainly lignin) could be liberated from their sodium salt forms and coagulated in acidification pretreatment. Neutralization of the organic substances also made their electro-migration less effective under electric driving force and in particular improved separation efficiency of chloride and organics. After acid-ED coupled treatment (pH = 2 and J = 40 mA·cm−2) [TOC] remarkably reduced from 1.315 g·L−1 to 0.048 g·L−1 and [Cl−] accumulated to 130 g·L−1 in concentrate solution. Recovery rate of NaCl was 89% and the power consumption was 0.38 kW·h·kg−1 NaCl. Irreversible fouling was not caused as electric resistance of membrane pile maintained stably. In conclusion, acidic-ED is a practical option to treat salinity organic wastewater when current techniques including thermal evaporation and pressure-driven membrane separation present limitations.

Wastewater from olaquindox-producing factories contains high levels of salts and organics. In this study, we investigated the multiple freeze-thaw technology to recover olaquindox from wastewater and decrease its chemical oxygen demand (COD) and salinity. Results suggested that under lower ice formation rate, the removal efficiencies of COD, electric conductivity, ammonia nitrogen and total nitrogen could reach 99.4%, 98.2%, 98.7% and 98.5% respectively. Higher ice formation rate, however, promoted wastewater concentration and volume reduction. A liter of wastewater concentrate can recover 11.5 g solid through a simple crystallization step at 4 °C for 12 h. This substance contained mostly olaquindox based on Raman infrared spectroscopy, scanning electron microscopy, and energy dispersive spectrometry. An industrial-scale wastewater treatment process, which the theoretical cost is one seventh that of conventional technologies, was then proposed to recover olaquindox and treat wastewater.

This article presents a novel method for integrating native corn starch and calcium carbonate (CaCO3) into a hybrid pigment, which can be applied in papermaking to increase the amount of starch in paper and improve sheet bonding without impairing dewatering. Starch was first thermally treated to partially gelatinize and swell the granules. The aim of the treatment was to change the surface properties of starch and thus to improve the interaction with CaCO3 particles. CaCO3 shell was precipitated around the swollen granules and the encapsulated starch was then cooked to achieve complete gelatinization. When the granules were cooked, the starch became active for bonding, but its solubility was very limited due to the encapsulation. Particle size measurement and scanning electron microscopy were used to analyze the sample properties during the preparation. The hybrid pigment was added to paper sheets and its effect on the paper properties was examined. Starch was shown to be effectively bound to the pigment structure. The hybrid pigment allowed a large amount of native corn starch to be added to paper without interfering with the papermaking process. Furthermore, it gave excellent mechanical paper properties.

Utilisation of lignin in plastic based blends offers a sustainable alternative to non-renewable materials as well as value-added use of technical lignin obtained from pulping operations. To overcome poor compatibility between lignin and plastic, in this study, two industrial lignins (softwood Kraft and agricultural fiber soda) were esterified (with acetic, propionic, butyric, and hexanoic anhydrides) and subsequently blended with poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) or polypropylene (PP) at a weight ratio of 3:7. This paper systematically characterized C2–C6 anhydrides esterified lignins (molar mass, glass transition temperature (Tg), hydrophobicity, and polarity), and provides a comprehensive evaluation of the effect of different lignin esters in the blends on tensile properties, water absorption, thermal transitions, for the first time, spherulite morphology, and dynamic rheological behaviour. Generally, compared to blends with unmodified lignin, a progressive increase of tensile strength (25%) and elongation at break (26%) could be observed with increasing ester carbon chain length in PHBV based systems, while no improvement was seen in PP based systems. Water absorption of PHBV and PP blends decreased by about 50% after lignin esterification. The effect of lignin esterification on the crystallization process was matrix dependent: depression of melting crystallization and occurrence of cold crystallization was observed in PHBV based blends, while the melting crystallization shifted to higher temperature in PP based blends. The lignin acetate and propionate blends were partially miscible showing two-stage glass transitions by thermal mechanical analysis. Esterification led to more uniform dispersion of lignin in the plastic matrix. The frequency of PHBV spherulites increased and their size decreased from 700 μm to less than 100 μm with addition of lignin acetate and propionate. Lignin hexanoate blends showed a Tg depression and smaller dynamic elastic and viscous moduli than the other lignin esters, suggesting that it acted as a plasticizer.

This study investigated the effects of biochar seeding (wheat straw biochar and rice husk biochar) on nutrient recovery via struvite formation, and improvements in the particle size of precipitated struvite from anaerobic digestate supernatant. Simultaneously, the influence of biochar seeding on heavy metal accumulation and elimination of pathogens (total coliforms and Escherichia coli) was evaluated under various operational factors, e.g., pH, supersaturation, reaction time, and seeding rates. Compared to the non-seeding process (maximum recovery efficiency of phosphate and ammonium 91% and 83%, respectively, with a particle size of 70 mu m) and the struvite-seeding process (maximum recovery efficiency of phosphate and ammonium 97% and 94%, respectively, with a particle size of 100 mu m), the process of biochar seeding improved nutrient recovery up to 7% and 11% for phosphate and ammonium, respectively, and increased struvite particle size by 43%, regardless of biochar type. XRD diffraction and FTIR analysis confirmed the prevalence of orthorhombic characteristics and an inner crystalline structure of the struvite formed by biochar seeding. About 75% of total coliforms and 70% of Escherichia coli were removed from the digestate supernatant through seeded struvite precipitation, regardless of the seeding materials. However, the biochar seeding process led to an accumulation of heavy metals in the acquired struvite product than that with non-seeded precipitation process. The concentrations of these metals were still well below permissible limits for application on agricultural land. It can be concluded that the inclusion of biochar as a seeding material might be a sustainable strategy to enhance struvite formation, intensify nutrient recovery, and yield high-quality struvite fertilizer with increased particle sizes. (C) 2018 Elsevier B.V. All rights reserved.

Itaconic acid is a biomolecule with potential application in various products, substituting feedstocks within the petrochemical industry. Simulations of different downstream trains were done to compare the method currently used in industry for recovery of itaconic acid with a) adsorption, b) reactive extraction and c) electrodialysis, to evaluate the most advantageous process considering production costs. In these simulations, adsorption is the method with greater potential to substitute the crystallization as the main downstream method, followed by reactive extraction, which showed values close to those of crystallization. The only non-competitive method was electrodialysis. The processing costs of itaconic acid were estimated at 1.13 US$ kg−1 for the upstream and fermentation, and extra 0.89, 0.63, 0.88, 1.50 US$ kg−1 for crystallization, adsorption, extraction, and electrodialysis-based processes, respectively.

The trend in utilizing biological industrial wastes to produce biofuels has been increasingly popular over the past decades. The dairy washed milk scum (DWMS) is one of such potential industrial waste, which can be used as feedstock for the production of biodiesel. One of the inherent problems of DWMS biodiesel is its poor low temperature properties. In this investigation, the influence of two solvents namely, Acetone (ACE) and Diethyl ether (DEE) was tested as cold flow improvers (CFI's) on low temperature properties of DWMS biodiesel. It was observed that the addition of 20% (v/v) of ACE and DEE to DWMS biodiesel improved the low temperature properties. The crystallization characteristics of biodiesel and its blends with CFIs were determined using differential scanning calorimetry (DSC). Other fuel properties were within the permissible limits of biodiesel standard (ASTM D6751-15C) with all the blends of ACE and DEE.

Nutrient recovery performance utilising an electrodialysis (ED) process was quantified in a 30-cell pair pilot reactor with a 7.2 m2 effective membrane area, utilising domestic anaerobic digester supernatant, which had been passed through a centrifuge as a feed source (centrate). A concentrated product (NH4-N 7100 ± 300 mg/L and K 2490 ± 40 mg/L) could be achieved by concentrating nutrient ions from the centrate wastewater dilute feed stream to the product stream using the ED process. The average total current efficiency for all major cations over the experimental period was 76 ± 2% (NH4-N transport 40%, K transport 14%). The electrode power consumption was 4.9 ± 1.5 kWh/kgN, averaged across the three replicate trials. This value is lower than competing technologies for NH4-N removal and production, and far lower than previous ED lab trials, demonstrating the importance of pilot testing. No significant variation in starting flux densities and cell resistance voltage for subsequent replicate treatments indicated effective cleaning procedures and operational sustainability at treatment durations of several days. This study demonstrates that ED is an economically promising technology for the recovery of nutrients from wastewater.

Amorphous solid dispersions (ASDs) are commonly manufactured using spray-drying processes. The product quality can be decisively influenced by the choice of process parameters. Following the quality-by-design approach, the identification of the spray-drying process design space is thus an integral task in drug product development. Aiming a solvent-free and homogeneous ASD, API crystallization and amorphous phase separation needs to be avoided during drying. This publication provides a predictive approach for determining spray-drying process conditions via considering thermodynamic driving forces for solvent drying as well as ASD-specific API/polymer/solvent interactions and glass transitions. The ternary API/polymer/solvent phase behavior was calculated using the Perturbed-Chain Statistical Associating Theory (PC-SAFT) and combined with mass and energy balances to find appropriate spray-drying conditions. A process design space was identified for the ASDs of ritonavir and naproxen with either poly(vinylpyrrolidone) or poly(vinylpyrrolidone-co-vinylacetate) spray dried from the solvents acetone, dichloromethane, or ethanol., Graphical abstract Unlabelled Image

The present study evaluates the crystal growth rate of amorphous drugs when dispersed in different ternary polymeric amorphous solid dispersions (ASDs) in the presence of surfactants. Specifically, ternary ASDs of aprepitant (APT, selected as a model drug) were prepared via melt-quench cooling by evaluating three commonly used ASDs matrix/carriers, namely hydroxypropyl cellulose (HPC), poly(vinylpyrrolidone) (PVP) and the copolymer Soluplus® (SOL), and two suitable surfactants, namely d-alpha tocopheryl polyethylene glycol 1000 succinate (TPGS) and poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) (P407). Results showed that all components were completely miscible (verified via hot stage polarized microscopy) and both surfactants were acting as plasticizers to the API. APT's crystal growth rate was increased in the presence of both P407 and TPGS, while PVP was identified as the matrix/carrier with the greatest impact API's crystal growth rate inhibition. Interestingly, TPGS presented a noticeable synergistic effect when combined with PVP resulting in a further reduction of APT's crystal growth rate. Furthermore, evaluation of APT's nucleation induction time in dissolution medium (PBS pH 6.8) revealed PVP as the most effective crystallization inhibitor, whereas the addition of TPGS showed to improve PVP's ability to inhibit APT's recrystallization. Finally, the formation of intermolecular interactions in the ternary APT-PVP-TPGS provided an explanation for the observed PVP-TPGS synergistic effects, with molecular dynamics simulations being able to unravel the type and extent of these interactions on a theoretical basis., Graphical abstract Unlabelled Image

Novel polymeric carriers for amorphous solid dispersions (ASDs) are highly demanded in pharmaceutical industry to improve the bioavailability of poorly-soluble drug candidates. Besides established polymer candidates, hydroxypropyl celluloses (HPC) comes more and more into the focus of ASD production since they have the availability to stabilize drug molecules in aqueous media against crystallization. The thermodynamic long-term stability of HPC ASDs with itraconazole and fenofibrate was predicted in this work with PC-SAFT and compared to three-months enduring long-term stability studies. The glass-transition temperature is a crucial attribute of a polymer, but in case of HPC hardly detectable by differential scanning calorimetry. By investigating the glass transition of HPC blends with a miscible polymer, we were for the first time able to estimate the HPC glass transition. Although both, fenofibrate and itraconazole reveal a very low crystalline solubility in HPC regardless of the HPC molecular weight, we observed that low-molecular weight HPC grades such as HPC-UL prevent fenofibrate crystallization for a longer period than the higher molecular weight HPC grades. As predicted, the ASDs with higher drug load underwent amorphous phase separation according to the differential scanning calorimetry thermograms. This work thus showed that it is possible to predict critical drug loads above which amorphous phase separation and/or crystallization occurs in HPC ASDs., Graphical abstract Unlabelled Image

Oil loss is a common problem in high oil volume fraction fat-structured foods, where trans fatty acids are absent and saturated fatty acids minimized. Usually a stabilizer “fat”, rich in behenic and stearic acids is added to these products. This stabilizer significantly reduces oil migration and loss; however, the mechanism by which it exerts its effect is not known. Here we study the structure and oil loss characteristics of blends of palm mid fraction (PMF) and palm olein (PO) mixed with a commercial stabilizer of fully hydrogenated cottonseed and rapeseed oils added at 1.25, 3.5, and 7% (w/w) levels. The addition of as little as 1.25% stabilizer reduced oil migration from 13% to ~ 2% for the 80:20 PMF/PO blend and from 29% to ~ 3.5% for 20:80 PMF/PO blend after 14 days of storage at 20 °C, as judged from a filter paper assay. Polarized light microscopy results demonstrated that addition of stabilizer decreased fat crystal size and lead to the formation of a denser network with smaller pores. The rate of crystallization, determined by monitoring increases in solid fat content as function of time by pulsed NMR, increased upon addition of the stabilizer as indicated by decreases in the half-time of crystallization. Addition of stabilizer lead to an increase in the mechanical strength of the material, as indicated by increases in breaking force. Differential scanning calorimetry showed the formation of a new fraction, intermediate between the high melting fractions in both PMF and PO and the stabilizer upon incorporation of the stabilizer in the blends. We hypothesize that the stabilizer helps the formation of this new fraction which has a higher nucleation rate and thus forms a denser network of small crystals with an improved ability to bind and retain oil.

Effect of alkaline solutions such as 10% NaOH, NaOH/urea and NaOH/ethylene glycol solutions on crystalline structure of different cellulosic fibers (cotton linter and filter paper) was investigated at room temperature and -4°C. The highest dissolution of cotton linter and filter paper was observed in NaOH/ethylene glycol at both temperatures. X-ray patterns of treated cotton linter with different alkaline solutions at low temperature showed only two diffractions at 2θ=12.5° and 21.0°, which belonged to the crystalline structure of cellulose II. CP/MAS (13)C NMR spectra showed the doublet peaks at 89.2 ppm and 88.3 ppm representing C4 resonance for cellulose I at room temperature, Whereas, at low temperature the doublet peaks were observed at 89.2 ppm and 87.8 ppm representing C4 resonance for cellulose II. Degree of polymerization of cellulose plays an important role in cellulose dissolution in different alkaline solutions and temperatures, where, a low temperature gives high dissolutions percentage with change in crystalline structure from cellulose I to cellulose II forms.

In this work, corn stover was refined by a pulp refining instrument (PFI refiner) after NaOH pretreatment under varied conditions. The quantitative characterization of the influence of PFI refining on enzymatic hydrolysis was studied, and it was proved that the enhancement of enzymatic saccharification by PFI refining of the pretreated corn stover was largely due to the significant increment of porosity of substrates and the reduction of cellulose crystallinity. Furthermore, a linear relationship between beating degree and final total sugar yields was found, and a simple way to predict the final total sugar yields by easily testing the beating degree of PFI refined corn stover was established. Therefore, this paper provided the possibility and feasibility for easily monitoring the fermentable sugar production by the simple test of beating degree, and this will be of significant importance for the monitoring and controlling of industrial production in the future.

Struvite crystallization is a chemicophysical process for nitrogen and phosphorus recovery, and its product can be used as a slow-release fertilizer. Heavy metals (mainly Cu and Zn) present in swine wastewater not only affect the crystallization kinetics, but also increase the product’s ecological risk and make it inadequate for agricultural applications. However, there is currently little research focusing on heavy metal minimization during struvite recovery. This paper is to develop a cost-effective operation strategy, in which minimum process modification and optimum phosphorus recovery could be achieved. The results indicated that the Cu and Zn co-precipitation was mainly controlled by the chemical reaction rather than adsorption during struvite crystallization, making the pre-removal of heavy metals possible. Increasing the ammonia nitrogen concentration could effectively inhibit the co-precipitation of Cu and Zn. When struvite crystallization was performed in synthetic swine wastewater, it was found that the pre-removal of Cu/Zn by chemical precipitation, followed by the increase in initial solution pH, could markedly reduce the Cu and Zn co-precipitation and their contents in the recovered struvite. A pilot-scale test validated such a recommendation. Compared to the conventional struvite crystallization process, the proposed approach could reduce 43.5% Cu and 77.6% Zn in the recovered struvite.

Poly (lactic acid) (PLA) reinforced with bleached kraft soft wood (BKSW) biocomposites with fibre content up to 35% were processed by kinetic mixing and injection moulding. The cellulosic filler was a commercial chemical bleached kraft soft wood pulps composed of well individualized fibres free from lignin with diameter about 20 μm and length within micron scale. The effect of fibre addition on the thermal properties of composites was investigated using differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), thermal gravimetric analysis (TGA) and thermo-mechanical analysis (TMA). In a previous work, it was demonstrated that fibre inclusion on PLA enhanced the modulus as well as the strength. Fibre addition promoted the crystallization of PLA by favouring the heterogeneous nucleation and accelerating the crystallization kinetic, without adversely altering the thermal stability. The DMA analysis confirmed the strong stiffening effect brought by the addition of fibres at the glassy as well as the rubbery domains. The presence of fibres had also a beneficial effect on the dimension stability by lowering the thermal expansion coefficient of composites.

A set of experiments was conducted so as to detect the influences of concerned factors including freezing temperature, stirring speed and pH adjustment on combined method of suspension crystallization and freeze-thaw technique for waste cutting fluid treatment and oil recovery. The optimal operating conditions of freezing temperature and stirring speed were confirmed by the experiment result to be −8 °C and 300 rpm respectively, while the chemical oxygen demand (COD) removal efficiency was above 90% without pH adjustment. The concentrates from the suspension crystallization were further treated by freeze-thaw method, and the oil recovery rate could reach to 95%. The micrograms of concentrates from suspension crystallization showed that the size of oil droplets in concentrates was about 148 μm in diameter, which became significantly larger after the suspension crystallization process. As a consequence, higher possibility for oil droplets to gather and separate was provided by their expanded size. The results of infrared spectroscopy studies indicated that the oil recovered from waste cutting fluid precipitates was mainly composed of esters. Up to 2.85 kg fat was recovered from 1 m 3 of waste cutting fluid, while the required power of the combined freezing process is theoretically 42 kW h. Based on the results, a freezing/concentration concept for oil recovery from waste cutting fluid is proposed.

The fruit of Rhus chinensis Mill. is traditionally used for the treatment of kidney diseases and urinary stones. The present work investigated the effectiveness of the extract obtained from the R. chinensis fruit pulp (RCFP) (water extract) on the inhibition of calcium oxalate (CaOx) crystallization in-vitro, at different concentrations (1–10 mg/mL). The rates of nucleation and aggregation were evaluated by comparing the slope of turbidity in the presence of the fruit extract with that obtained in the control. The results of the samples were compared with a parallel study conducted with standards like Citric acid (CA) and Malic acid (MA), Cystone- a marketed polyherbal combination (CYS), under identical concentrations. The densities of the formed crystals were observed under a light microscope. RCFP (water extract) significantly inhibited the slope of nucleation and aggregation of CaOx crystallization, and decreased the crystal density. The standards- CA, MA and CYS also exhibited similar effects. The study reveals that the organic acid in RCFP (water extract) was found effective in the prevention of the experimentally induced urinary stones and thus substantiating the traditional claim. Hence, the fruit of R. chinensis has a beneficial inhibitory effect on in-vitro crystallization of CaOx crystals.

We demonstrate a facile, single step, low temperature and energy efficient strategy for the synthesis of SnO2-reduced graphene oxide (RGO) nanocomposite where the crystallization of SnO2 nanoparticles and the reduction of graphene oxide takes place simultaneously by an in situ chemical reduction process. The electrochemical property of the SnO2-RGO composite prepared by using low concentrations of reducing agent shows better Li storage performance, good rate capability (378 mAh g−1 at 3200 mA g−1) and stable capacitance (522 mAh g−1 after 50 cycles). Increasing the reductant concentration lead to crystallization of high concentration of SnO2 nanoparticle aggregation and degrade the Li ion storage property.

In this paper, attempts were made to develop an in situ product removal process for magnesium lactate production based on crystallization. The crystallization was conducted at 42 °C without seed crystal addition. The product concentration, productivity and yield of fermentation coupled with in situ product removal (ISPR) reached 143 g L −1 , 2.41 g L −1 h −1 and 94.3%. In four cycles of crystallization, the average reuse rate of fermentation medium and removal rate of product reached 64.0% and 77.7%. At the same time, ISPR fermentation saved 40% water, 41% inorganic salts and 43% yeast extract (YE) as compared to fed-batch fermentation. The process introduces an effective way to reduce the amount of waste water and the raw material cost in magnesium lactate fermentation.

Fabrication of ZnO/graphene hybrid by homogeneous depositing a continuous and conformable ZnO layer on graphene remains a great challenge and highly desired. In this paper, well-defined flake-like ZnO/graphene hybrid was fabricated by a facile in situ hydrolysis-deposition route using zinc acetate and graphene oxide (GO) as starting materials and ammonia as precipitator and reductant. By rational control the hydrolysis and condensation of Zn precursor, ZnO nanocrystals are homogeneously anchored on graphene due to the strong interaction between ZnO and GO, which was simultaneously reduced to graphene. The photocatalytic activity of the photocatalyst was evaluated using Brilliant Red X-3B (X3B) dye as probe. It was found that the presence of GO enhanced the crystallization of ZnO, and the photocatalytic activity of ZnO/graphene hybrid increases first and then decreases with increasing the amount GO. The hybrid with 3 wt.% of GO shows the highest photocatalytic activity, which is 3 times higher than that of pure ZnO.

Simultaneously ultrasonic wave and microwave assisted technique (SUMAT), as a method of process intensification, was first applied to the preparation of nanocellulose whiskers (NCWs) from filter paper by sulfuric acid hydrolysis. The effects of temperature, sulfuric acid concentration, and mass of raw material and time on the yield of NCWs were investigated by single-factor experiments, and the preparation conditions were optimized with response surface methodology. The obtained NCWs were characterized by transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction and thermal gravimetry. The results showed NCWs were facilely prepared by using SUMAT. However, some harsh reaction conditions such as high temperature, strong acidity and long time treatment easily induced the reduction of the yield of NCWs. Under the optimal conditions, the yield and the crystallinity of NCWs with the crystal form of cellulose Iα is 85.75% and 80%, respectively.

The recovery and removal of nutrients from swine wastewater was investigated by employing a struvite recycling process, which used magnesium phosphate (MP) as the active component. In this study, the effect of organic matters (sodium alginate, bovine albumin and acetic acid) in swine wastewater on the crystallization of struvite and the feasibility of MP as the phosphate and magnesium sources of struvite precipitation were first evaluated. The results demonstrated that sodium alginate and bovine albumin could slightly influence the crystallization of struvite while acetic acid did not. Using MP as the phosphate and magnesium sources of struvite precipitation could achieve a removal efficiency of the total ammonia nitrogen (TAN) close to that of using pure chemicals (MgCl2∙6H2O and Na2HPO4∙12H2O). The results of struvite pyrgenation revealed that the optimal pyrogenation condition of struvite was at Mg(OH)2:NH4+ 1:1 and temperature 150 °C for 3 h, at which the main pyrogenation product was MP. Recycling the pyrolysate at pH 8.5 could achieve a TAN removal of 78%. When the pyrolysate was recycled for six cycles, the TAN removal efficiency could be maintained above 70%, and 67% of the struvite precipitation cost could be reduced compared to using pure chemicals.

Pretreatment with ozone combined with aqueous ammonia was used to recover residual organic carbon from recalcitrant solid digestate for ethanol production after anaerobic digestion (AD) of rice straw. Methane yield of AD at mesophilic and thermophilic conditions, and ethanol production of solid digestate were investigated. The results showed that the methane yield at thermophilic temperature was 72.2% higher than that at mesophilic temperature under the same conditions of 24 days and 17% solid concentration. And also the ethanol production efficiency of solid digestate after thermophilic process was 24.3% higher than that of solid digestate after mesophilic process. In this study, the optimal conditions for integrated methane and ethanol processes were determined as 55 °C, 17% solid concentration and 24 days. 58.6% of glucose conversion, 142.8 g/kg of methane yield and 65.2 g/kg of ethanol yield were achieved, and the highest net energy balance was calculated as 6416 kJ/kg.

The feasibility of a continuous chemically-enhanced seeded precipitation (CCESP) process was evaluated for desupersaturation of primary reverse osmosis (PRO) concentrate generated from RO desalting of inland agricultural drainage (AD) water with high gypsum scaling potential. The CCESP approach, comprised of partial lime treatment (PLT) followed by gypsum seeded precipitation (GSP), was assessed via laboratory and field tests, along with model simulations. PLT effectiveness was confirmed for residual antiscalant removal from the PRO concentrate, which otherwise would suppress gypsum crystallization. GSP was carried out in a fluidized bed crystallizer (FBC) demonstrating the feasibility of continuous PRO concentrate desupersaturation with suitable solids management. FBC operation was stable, with respect to desupersaturation performance, when operating over a sequence of periodic solids purge-only mode with intermittent seeds replenishment. The study suggests that CCESP integration with primary and secondary RO desalting (i.e., PRO-CCESP-SRO) can provide for significant enhancement of product water recovery for inland water of high gypsum scaling propensity. For example, source water of high salinity (14,347 mg/L total dissolved solid) AD water, nearly saturated with respect to gypsum, could be desalted up to a recovery of 88-96% (relative to merely 66% recovery feasible via PRO desalting. Moreover, net salt harvesting of 2.6-3.6 kg per m3 RO concentrate (with concentrate recycle) can be obtained from high recovery desalting of the above PRO concentrate.

The formation of struvite crystals or magnesium ammonium phosphate (MgNH4PO4) in palm oil mill effluent (POME) occurs as early as in the secondary stage of POME treatment system. Its growth continues in the subsequent tertiary treatment which reduces piping diameter, thus affecting POME treatment efficiency. Hypothesis. The beneficial use of the crystal is the motivation. This occurrence is rarely reported in scientific articles despite being a common problem faced by palm oil millers. The aim of this study is to characterize struvite crystals found in an anaerobic digester of a POME treatment facility in terms of their physical and chemical aspects. The compositions, morphology and properties of these crystals were determined via energy dispersive spectroscopy (EDS), elemental analysis, scanning electron microscopy (SEM) and x-ray diffraction (XRD). Solubility tests were carried out to establish solubility curve for struvite from POME. Finally, crystal growth experiment was done applying reaction crystallization method to demonstrate struvite precipitation from POME. Results showed that high phosphorous (P) (24.85 wt%) and magnesium (Mg) (21.33 wt%) content was found in the struvite sample. Elemental analysis detected carbon (C), hydrogen (H), nitrogen (N) and sulfur (S) below 4 wt%. The crystals analysed by XRD in this study were confirmed as struvite with 94.8% struvite mineral detected from its total volume. Having an orthorhombic crystal system, struvite crystals from POME recorded an average density of 1.701 g cm−3. Solubility curve of struvite from POME was established with maximum solubility of 275.6 mg L−1 at pH 3 and temperature 40 °C. Minimum solubility of 123.6 mg L−1 was recorded at pH 7 and temperature 25 °C. Crystal growth experiment utilizing POME as the source medium managed to achieve 67% reduction in phosphorous content. This study concluded that there is a potential of harnessing valuable nutrients from POME in the form of struvite. Struvite precipitation technology can be adapted in the management of POME in order to achieve maximum utilization of the nutrients that are still abundant in POME. At the same time maximization of nutrient extractions from POME will also reduce pollutants loading in the final discharge., Crystal; Industrial wastewater; Nutrient recovery; Palm oil mill; Struvite precipitation.

Amorphous solid dispersions (ASDs) of lumefantrine, which has low aqueous solubility, have been shown to improve bioavailability relative to crystalline formulations. Herein, the crystallization tendency and release properties of a variety of lumefantrine ASD granules, formed on a blend of microcrystalline cellulose and anhydrous lactose, prepared using a simple solvent evaporation method, were evaluated. Several polymers, a majority of which contained acidic moieties, and different drug loadings were assessed. Crystallinity as a function of time following exposure to stress storage conditions of 40 °C and 75% relative humidity was monitored for the various dispersions. Release testing was performed and ASD characteristics were further evaluated using infrared and X-ray photoelectron spectroscopy (XPS). A large difference in stability to crystallization was observed between the various ASDs, most notably depending on polymer chemistry. This could be largely rationalized based on the extent of drug-polymer interactions, specifically the degree of lumefantrine-polymer salt formation, which could be readily assessed with XPS spectroscopy. Lumefantrine release from the ASDs also varied considerably, whereby the best polymer for promoting physical stability did not lead to the highest extent of drug release. Several formulations led to concentrations above the amorphous solubility of lumefantrine, with the formation of nano-sized drug-rich aggregates. A balance between the ability of a given polymer to promote physical stability and drug release may need to be sought., Graphical abstract Unlabelled Image