Extrusion-spheronization Method Research Articles

Study on CaO-based materials derived from steel slag for solar-driven thermochemical energy storage

The calcium looping (CaL) technique, renowned for its exceptional ability to withstand high temperatures and remarkable heat storage capacity, perfectly complements 3rd generation concentrated solar power (CSP) plants. However, the poor cycling stability and low spectrum absorption rate of CaO obstruct system efficiency. In order to tackle these problems, we impregnated steel slag with acetic acid and doped Mn to create a novel CaO-based energy storage material. Thermogravimetric analysis (TGA) and fixed-bed cycling of the material revealed that the material has outstanding cyclic heat storage properties. Compared to CaO, the material has an 85 % higher initial adsorption rate, 73 % higher 30-cycle energy storage density, and 9.5 times higher average light absorption. Spherical pellets were prepared for industrial applications through the extrusion-spheronization method. The energy storage density for 30 cycles was reduced by 10.26 % for the pellets compared to the powder material, but the average light absorption rate was improved. The compressive strength of the composite pellets was 8.4 times higher than the dolomite pellets. It was found that the light absorption capacity of the material increased with the number of cycles, which was attributed to the migration of Mn and Mg from the interior to the surface. Finally, the excellent photothermal conversion capability of the new composite material was verified by the photothermal conversion test. Therefore, Mn-doped CaO-based composite material derived from steel slag is promising for application in the next-generation CaL-CSP system.

Preparation and evaluation of lipid-based sustained release pellets of chlorpheniramine maleate by the wet extrusion-spheronization method

Introduction: This study aimed to investigate the feasibility of preparation of sustained-release chlorpheniramine maleate (CPM) pellets based on Compritol® as a lipid matrix and evaluation of the affecting factors on pellet properties. Methods: Using the D-optimal experimental design, different pellet formulations containing various amounts of CPM, Compritol® and Avicel were prepared by the wet extrusion-spheronization method. Then the pellets were cured at 40, 65 and 90 ̊C for 4 and 8 h to study the effect of the thermal process. The physicomechanical properties of the pellets were investigated in terms of particle size distribution, pelletization yield, mechanical strength, aspect ratio and sphericity. To investigate the possible interaction of CPM and Compritol®, as well as to evaluate the morphology and surface characteristics of the pellets DSC and SEM were used, respectively. Also, to investigate the drug release rate from pellets the dissolution test was carried out and mean dissolution time (MDT) was calculated to compare different formulations. Results: The results showed that the curing process up to 65 °C improves the strength of the pellets. However, increasing the curing temperature from 65 to 90 °C and also increasing the curing time from 4 to 8 h did not have a significant effect on the strength of the pellets but increased the drug release rate of pellets. Increasing the amount of the drug or decreasing Compritol® in the matrix of pellets leads to a larger particle size with greater mechanical strength. All formulations of the pellets had an aspect ratio and sphericity of about 1.1 and 0.9 respectively, which indicates the spherical shape of the pellets as shown by SEM. DSC thermograms indicate the reduction of the crystallinity or the change of the crystalline form of the drug to amorphous during the pelletization process. Conclusion: The results revealed the feasibility of preparing lipid-based sustained-release matrix pellets using the wet extrusion-spheronization method. The optimal formulation in terms of physicomechanical properties and release rate was the formulation containing 8% CPM, 67% Compritol® and 25% Avicel, which were dried at 40 ° C for 4 h and released about 90% of the drug within 12 h.

Long-Term performance of composite Cu-Fe ore oxygen carrier by Extrusion-Spheronization in chemical looping combustion

High-performance and low-cost oxygen carrier is vital for engineering demonstration and industrial application of chemical looping combustion. In this work, binary-ore (copper ore and iron ore) oxygen carriers are prepared at a large scale (25 kg/h) by the extrusion-spheronization method, using montmorillonite as the inert support. The anti-sintering ability and long-term stability are systematically investigated through well-organized tests in a thermogravimetric analyzer (TGA) and batch fluidized bed reactor (BFB). Four kinds of low-cost composite oxygen carriers are prepared with montmorillonite content of 10 wt%∼40 wt%, and the montmorillonite loading ratio is optimized as 10 wt% through 100-cycle TGA tests, with the fastest reduction rate of 0.155 %/s. The results show that the CO2 yield is always beyond 90 %, suggesting the stable reactivity of FeCu-10 M, and the average attrition rate is 0.108 %/h. No significant sintering or agglomeration is detected in the inner surface or among the particles, as indicated by SEM images. The specific surface area is developed from 0.125 to 0.185 m2/g, and the rich pore structure remains in the 100-cycle test. Additionally, the crushing strength of FeCu-10 M is higher than 2 N throughout the cyclic experiment, and the lifetime is 2 ∼ 7 times longer than that of the original iron ore. The extrusion-spheronization method has the potential in the industrial-scale preparation of oxygen carriers, and the FeCu-10 M is a favorable oxygen carrier to the chemical looping combustion process.

Preparation and evaluation of lipid-based sustained release pellets of chlorpheniramine maleate by the wet extrusion-spheronization method

Background: This study aimed to investigate the feasibility of preparation of sustained-release chlorpheniramine maleate (CPM) pellets based on Compritol® as a lipid matrix and evaluation of the affecting factors on pellet properties. Method: Using the D-optimal experimental design, different pellet formulations containing various amounts of CPM, Compritol® and Avicel were prepared by the wet extrusion-spheronization method. Then the pellets were cured at 40, 65 and 90 ̊C for 4 and 8 h to study the effect of the thermal process. The physicomechanical properties of the pellets were investigated in terms of particle size distribution, pelletization yield, mechanical strength, aspect ratio and sphericity. To investigate the possible interaction of CPM and Compritol®, as well as to evaluate the morphology and surface characteristics of the pellets DSC and SEM were used, respectively. Also, to investigate the drug release rate from pellets the dissolution test was carried out and mean dissolution time (MDT) was calculated to compare different formulations. Results: The results showed that the curing process up to 65 °C improves the strength of the pellets. However, increasing the curing temperature from 65 to 90 °C and also increasing the curing time from 4 to 8 h did not have a significant effect on the strength of the pellets but increased the drug release rate of pellets. Increasing the amount of the drug or decreasing Compritol® in the matrix of pellets leads to a larger particle size with greater mechanical strength. All formulations of the pellets had an aspect ratio and sphericity of about 1.1 and 0.9 respectively, which indicates the spherical shape of the pellets as shown by SEM. DSC thermograms indicate the reduction of the crystallinity or the change of the crystalline form of the drug to amorphous during the pelletization process. Conclusion: The results revealed the feasibility of preparing lipid-based sustained-release matrix pellets using the wet extrusion-spheronization method. The optimal formulation in terms of physicomechanical properties and release rate was the formulation containing 8% CPM, 67% Compritol® and 25% Avicel, which were dried at 40 ° C for 4h and released about 90% of the drug within 12 h.

Development and Characterization of Pectin-Based Colon Targeted Pellets Containing Lactobacillus Plantarum FNCC-0461

Lactobacillus plantarum FNCC-0461 is a lactic acid bacteria isolated from "dadih" a traditional Indonesian food that has potential as a probiotic. Probiotics can show health benefits if they can maintain cell viability of at least 7 log CFU in the distal ileum and colon. However, most probiotics are not resistant to the extreme conditions of the gastrointestinal tract. Probiotic encapsulation in the form of pectin-based colon targeted pellets is a promising delivery system to overcome probiotic viability problems due to the gastrointestinal tract extreme conditions and can assist release to specific target site in colon. Pellets was produced by extrusion-spheronization method using microcrystalline cellulose (MCC), lactose and pectin. Optimization of spheronization process was carried out by varying the spheronization speed and time while the optimization of pellets formula was carried out by varying the concentration of total pectin and the type of coating polymer (cellulose acetate phthalate (CAP) or shellac). The morphology, particle size, moisture content, micromeritic properties, process yield and viability of pellets were evaluated. Release of probiotics on coated and uncoated pellets were examined at pH 1.2, 6.8 and 7.4 under simulated colon fluid for 24 hours. The formula containing MCC, lactose and pectin (5:4:1) with spheronization speed at 1500 rpm for 15 minutes showed the best pellets characteristic and cell viability. The pellets obtained were spherical, with particle size distribution of 913.57±8.28 μm, process yield of 88.71±1.04 % and viability of 7.50 x 107 cfu/g. Pellets coated with CAP showed the highest cell release in simulated colon fluid of 1.38 x 107 CFU/g at 24 hours. This research proved that CAP coated pellet formulation has promising potential for colon targeted delivery of L. plantarum as well as to protect the viability of probiotics for colon-targeted delivery.

Combining solid lipid-nanoparticles in Alginate coating formulation to prepare enteric-released Diclofenac pellets

In the trend of using natural-resource substances in current pharmaceutical industry, alginate (ALG) film was used to coat tablets. To further develop ALG film-coating, solid lipid nanoparticles of cetearyl alcohol (ACS) or glycerol monostearate (GMS) were added in the coating formulation, applying to the diclofenac sodium (Na-D) pellet. Na-D pellets were prepared by the extrusion-spheronization method. Coated pellets were characterized with anti-moisture and acidic-resistant, and dissolution properties. Also, coating morphology was observed by microscopy and scanning electron microscopy (SEM); difference-scanning-calorimetry (DSC) and infrared (IR) spectroscopy were used to characterize the coating structure. The results showed that the nanoparticles were uniformly distributed into ALG structure. Interestingly, lipid nanoparticles enhaced the flexibility of the film, in which GMS nanoparticles improved the film-formed process (significantly lowering glass transition temperature). Regarding functions of the coating membrane, the moisture resistance and acid resistance of Na-D pellets increased only when nanolipids were present in the membrane.

Coal fly ash-bound limestone-derived sorbent pellets for high-temperature CO2 capture

Poor CO2 capture stability and serious elutriation are the issues commonly occur when limestone circulating in the fluidized bed-based Calcium Looping (CaL) system. Hence, three types of coal fly ash-bound (CFA-bound) limestone-derived sorbents were synthesized via mixing the limestone, calcined lime and hydrated lime with coal fly ash, respectively. The generated ternary Ca-Al-O and Ca-Si-O phases offer structural stability for CFA-bound limestone-derived sorbents and improve their cyclic CO2 capture performance. Moreover, extrusion-spheronization method was adopted to produce CFA-bound limestone and hydrated lime sorbent pellets to synergistically enhance cyclic CO2 capture capability and mechanical properties. It is found that hydrated lime is superior to limestone as the calcium precursor to prepare CaO-based sorbent pellets due to its desirable pore structure and high binding force. Therefore, the CFA-bound hydrated lime pellets containing 15 wt % of fly ash (HL/CFA15-P) exhibits a high carbonation conversion of 40 % after 17 cycles, which is nearly 1.4 times that of limestone pellets. The discrepancy on carbonation conversion between the two sorbent pellets is enlarged to ∼1.6 times after 100 cycles, which is calculated using a semi-empirical equation. Moreover, HL/CFA15-P exhibits outstanding mechanical property, whose compressive strength reaches 6±1.7 MPa, which is comparable to the cement-bound CaO-based sorbent pellets.

Fabrication of structurally improved KNaTiO3 pellets derived from cheap rutile sand for high-temperature CO2 capture

For the practical applications of CO2 sorbents, more studies on pellet rather than powder-type sorbents is a more mainstream research trend. In addition, high sorption kinetics, excellent cycling stability, and cheap raw precursors are far more important than its initial CO2 uptake value to a certain extent. Recently, alkali titanates have attracted growing attention as emerging and attractive high-temperature CO2 sorbent materials. Among the existing Na-doped alkali titanates, potassium sodium titanate (KNaTiO3) is one of the most promising high-temperature CO2 sorbent due to its high CO2 sorption rate and excellent cyclic stability. In order to promote its practical application in industry, a low-priced titanium ore was selected for the synthesis of KNaTiO3, and the optimized resulting sorbent maintained a rapid and reversible sorption capacity of 15.5 wt% after 100 cycles. Spherical pellets were fabricated by extrusion-spheronization method with cellulose and alumisol additives. The optimal pellets exhibited a relative compression strength of 4.15 MPa and an attrition rate of 1.2 wt% as well as maintaining a sorption capacity of 14.3 wt% after 50 cycles. It also showed superior CO2 capture kinetics, reaching a high CO2 removal rate of 92.5% within only 4 min (under 20% CO2). The role and mechanism of cellulose as pore-former were explored by SEM analysis and diffusion model fitting. In all, the optimized resulting sorbent pellets not only retained rapid CO2 sorption kinetics, high CO2 removal rate, excellent cyclic performance, but also ensure robust mechanical properties. These properties, as well as the low cost aspect, makes this newly developed KNaTiO3-based pellets to be highly promising for high temperature CO2 capture such as for biomass fired power plants or hydrogen production.

Facile fabrication of silica aerogel supported amine adsorbent pellets for Low-concentration CO2 removal from confined spaces

Amine-based adsorbents show promise for removing low-concentration CO2 from environmental control and life support systems (ECLSSs), while the powder adsorbents are facing the challenges of reaction non-uniformity, pressure drop and material elutriation. To solve the problems, amine-based adsorbent pellets are fabricated by the extrusion–spheronization (ES), agar-assisted moulding (AM) and graphite-casting (GC) methods. The adsorbent pellets are further modified with pore-forming template for improved CO2 adsorption performance. The influences of granulation and pore-forming template modification on the structure-performance relationships of the adsorbent pellets are investigated. Granulation exerts adverse effect on the pore structure of tetraethylenepentamine supported on silica gel (TEPA-SG) adsorbent, which is not conducive to the bulk diffusion of CO2, and the CO2 adsorption capacity and kinetics thus have been impaired. The TEPA-SG-ES adsorbent pellets prepared by the extrusion–spheronization method show a relatively higher CO2 capture capacity of 1.01 mmol CO2/g due to better textural parameters and uniform dispersion of amine species. Thanks to the extrusion process, the adsorbent pellets also exhibit good mechanical properties with a high compressive strength of 10.90 MPa and low abrasion index of 0.36%. Both the textural properties and CO2 uptakes of the pellets can be restored upon template modification, and the promoting effect depends on the different templates employed due to their distinct pyrolysis rates and pathways. Mechanical properties will be adversely affected by the doped pore-forming template. The TEPA-SG-ES-UA pellets prepared with urea modification exhibit a great CO2 capture capacity of 1.48 mmol CO2/g and good mechanical properties with a high compressive strength of 4.90 MPa and a low abrasion index of 0.87%, and it could be a nice adsorbent candidate for removing low-concentration CO2 from ECLSSs.

Comparison of 5-ASA layered or matrix pellets coated with a combination of ethylcellulose and eudragits L and s in the treatment of ulcerative colitis in rats

The aim of this study was to evaluate and optimize the combination of time and pH-dependent polymers as a single coating for the design of the colon-specific drug delivery system of 5-aminosalicylic acid (5-ASA) pellets. 5-ASA matrix pellets with a 70% drug load were prepared by the extrusion-spheronization method. The optimal coating formula which included Eudragit S (ES) + Eudragit L (EL) + Ethylcellulose (EC) was predicted for the targeted drug delivery to the colonic area by a 32 factorial design. The ratio of ES:EL:EC and coating level were considered as independent variables while the responses were the release of less than 10% of the drug within 2 h (Y1), the release of 60–70% within 10 h at pH 6.8 (Y2) and lag time of less than 1 h at pH 7.2 (Y3). Also, 5-ASA layered pellets were prepared by the powder layering of 5-ASA on nonpareils (0.4–0.6 mm) in a fluidized bed coater and then coated with the same optimum coating composition. The coated 5-ASA layered or matrix pellets were tested in a rat model of ulcerative colitis (UC) and compared with the commercial form of 5-ASA pellets (Pentasa®). The ratio of ES:EL:EC of 33:52:15 w/w at a coating level of 7% was discovered as the optimum coating for the delivery of 5-ASA matrix pellets to the colon. The coated 5-ASA pellets were spherical with uniform coating as shown by SEM and met all of our release criteria as predicted. In-vivo studies demonstrated that the optimum 5-ASA layered or matrix pellets had superior anti-inflammatory activities than Pentasa® in terms of colitis activity index (CAI), colon damage score (CDS), colon/body weight ratio and colon’s tissue enzymes of glutathione (GSH) and malondialdehyde (MDA). The optimum coating formulation showed a high potential for colonic delivery of 5-ASA layered or matrix pellets and triggered drug release based on pH and time.

Granulation of Mn-based perovskite adsorbent for cyclic Hg0 capture from coal combustion flue gas

Circulating adsorbents in a fluidized bed integrating elemental mercury (Hg0) adsorption and oxidized mercury decomposition/desorption processes could simultaneously achieve adsorbents recycling and mercury recovery during the flue gas mercury removal. The granulation of adsorbent powder is essential to reduce elutriation the looping system. Herein, powdery La0.8Ce0.2MnO3 perovskite adsorbent, which has been demonstrated to be highly efficient for Hg0 removal, was moulded into 0.8–1 mm pellets by an extrusion-spheronization method. Meanwhile, microcrystalline cellulose (MC) was used as pore-creating template to constructing porous pellets. The results show that the La0.8Ce0.2MnO3 pellets with 20 % MC added during the pelleting process (LCMO-MC) exhibited 90 % Hg0 removal efficiency under a gaseous hourly space velocity (GHSV) of 380,000 h−1, which was comparable to that over the corresponding powdery adsorbent. The LCMO-MC performed well in Hg0 removal at a wide temperature window from 50 to 200 °C. SO2 and H2O displayed slight interference in Hg0 removal, while O2 and NO enhanced Hg0 removal over LCMO-MC. During six adsorption-decomposition/desorption cycles, the LCMO-MC presented outstanding cyclic durability and about 97 % Hg0 removal efficiency was achieved with a GHSV of 50,000 h−1. The excellent Hg0 removal capacity of LCMO-MC was ascribed to the existence of abundant pore channels for Hg0 diffusion, which in-situ retained during the burning of pore-creating templates at high temperature and newly formed accompanying with the burning gas release. These results demonstrate that the template (i.e., MC) assisted extrusion-spheronization approach is promising to mould adsorbent pellets for Hg0 removal in a fluidized-bed system, which could simultaneously realize adsorbent recycling and mercury recovery.

Enhanced CO2 Capture Durability and Mechanical Properties Using Cellulose-Templated CaO-Based Pellets with Steam Injection during Calcination

Cellulose-templated CaO-based pellets were prepared via an extrusion–spheronization method. However, the CO2 capture capacity of the modified sorbents still deteriorated rapidly after multiple cycles, and the mechanical properties were also reduced. Steam injection during calcination was conducted to enhance the CO2 capture performance of the sorbents. The modified pellets with 10 vol % steam injection present a faster carbonation rate compared to sorbents calcined under higher steam concentrations. A CO2 uptake of 0.32 g/g was obtained after 20 cycles, 133 and 60% higher than the raw sorbent and modified sorbent without steam reactivation. Moreover, the simultaneous thermal and atmosphere-induced sintering resulted in a nearly 4 times enhancement of the mechanical strength of the sorbents from 3.9 to 14.7 N. Under the harsh environment (calcined at 950 °C), the presence of steam further aggravated the sintering of the sorbent, resulting in a dramatic decrease in CO2 uptake.

Preparation and Characterization of a Novel Multiparticulate Dosage Form Carrying Budesonide-Loaded Chitosan Nanoparticles to Enhance the Efficiency of Pellets in the Colon.

An attempt was made to conquer the limitation of orally administered nanoparticles for the delivery of budesonide to the colon. The ionic gelation technique was used to load budesonide on chitosan nanoparticles. The nanoparticles were investigated in terms of size, zeta potential, encapsulation efficiency, shape and drug release. Then, nanoparticles were pelletized using the extrusion-spheronization method and were investigated for their size, mechanical properties, and drug release. Pellets were subsequently coated with a polymeric solution composed of two enteric (eudragit L and S) and time-dependent polymers (eudragit RS) for colon-specific delivery. All formulations were examined for their anti-inflammatory effect in rats with induced colitis and the relapse of the colitis after discontinuation of treatment was also followed. The size of nanoparticles ranged between 288 ± 7.5 and 566 ± 7.7 nm and zeta potential verified their positive charged surface. The drug release from nanoparticles showed an initial burst release followed by a continuous release. Pelletized nanoparticles showed proper mechanical properties and faster drug release in acidic pH compared with alkaline pH. It was interesting to note that pelletized budesonide nanoparticles released the drug throughout the GIT in a sustained fashion, and had long-lasting anti-inflammatory effects while rapid relapse was observed for those treated with conventional budesonide pellets. It seems that there is a synergistic effect of nanoformulation of budesonide and the encapsulation of pelletized nanoparticles in a proper coating system for colon delivery that could result in a significant and long-lasting anti-inflammatory effect.

Formulation Development and Optimization of Multiparticulate System by Extrusion Spheronization Method

Aim: This study aimed at formulating and optimizing the multiparticulate system of Rifaximin by adopting 32 factorial designs with independent variables X1 and X2 as concentrations of two excipients.
 Methodology: The pellets were prepared by the Extrusion Spheronization method and evaluated for percentage yield, flow property, percentage drug content, friability, and in-vitro percentage cumulative drug release.
 Results: The optimized batch (OR7) displayed excellent flow properties, 0.15±0.03% friability, and 97.85±0.22% drug content with a cumulative drug release of 93.24±0.95%.
 Conclusion: The results confirm the usefulness of factorial design to identify the effect of variables on pellet characteristics. The optimized batch can further be coated with different polymers to obtain targeted drug delivery.
 Place of Study: Department of Pharmaceutics, M. C. E. Society’s Allana College of Pharmacy, Pune.

Solid self‑emulsifying pellets: Solubility enhancement for oral delivery of poorly soluble BCS Class II drug

The review focused on technique of solid self-emulsifying pellets (SEPs) for solubility enhancement of poorly water soluble drug. The oral route of administration has been and still is currently the primary route of drug delivery owing to its potential advantages compared to the other routes. The solubility enhancement process of hydrophobic drugs plays a key role in the formulation development to achieve the bioavailability and therapeutic action of the drug at the target site.1 Around 40% of probe new drugs are characterized as belonging to class II in the BCS classification (poorly water soluble and highly permeable), giving rise to poor and erratic oral bioavailability. The solid SEPs system combines the advantages of liquid Self emulsifying drug delivery system with those of solid dosage form, which can overcome the limitations of liquid formulations and improve the storage stability and patient compliance. To enhance the dissolution and oral absorption of water insoluble drug selfmicroemulsifying pellets develop and evaluated. SEPs pellets showed a significant quicker redispersion rate than the dissolution rate of commercial tablets. The solid SEPs pellets might be an encouraging strategy to improve the oral absorption of Poorly water soluble drug and the extrusion–spheronization method is a feasible technology for the solidification of liquid SMEPs. Self microemulsifying drug delivery system (SEPs) as an effective bioavailability enhancement pharmaceutical technology has been widely used during the recent years and have some successful products in the market (e.g. Neoral®, Norvir® and Fortovase®).
 Keywords: Self Emulsifying Pellets, Bioavailability, Solubility, extrusion–spheronization, Biopharmaceutical Classification.

Unravelling the pore templating effect on CO2 adsorption performance of alkali metal nitrates promoted MgO pellets

Alkali metal salts (AMS) promoted MgO with high CO2 uptakes represents a promising adsorbent candidate for CO2 capture. The AMS-MgO composite adsorbents are facing the challenges of increased pressure drop or elutriation when employed in dual fixed-bed reactor or twin circulating fluidized-bed configurations. Granulation by the extrusion-spheronization technique represents an effective problem-solving strategy. However, textural properties and CO2 uptakes of MgO-based adsorbent pellets might be adversely affected by the granulation process. In this work, AMS-MgO composite adsorbent pellets were prepared by the extrusion-spheronization method. Citric acid (CA), ammonium bicarbonate (AB), urea (UA) and microcrystalline cellulose (MC) were employed as pore-forming templates to improve the porous structures and CO2 uptakes of the AMS-MgO pellets. CO2 uptakes and adsorption kinetics of the adsorbent pellets were studied using a fixed-bed reactor. Effects of granulation and pore templating on the structure-performance relationships of the AMS-MgO pellets were unraveled. Granulation had resulted in the remarkable decrease in CO2 uptake from 10.87 to 4.24 mmol CO2/g due to the impaired textural parameters. The employed sacrificial templates endowed the AMS-MgO pellets with enhanced CO2 uptakes and improved carbonation kinetics. This was associated with extended surface area and expanded pore structures due to gas liberation in the pyrolysis of templates, which had facilitated the kinetics of CO2 bulk diffusion. The desired AMS-MgO-MC pellet modified with MC template showed a high CO2 uptake of 7.54 mmol CO2/g in 50%CO2 at 340 °C, and its CO2 uptake was stabilized around 5.0 mmol CO2/g within 20 cycles. Besides, the AMS-MgO-MC pellet also exhibited good mechanical properties. The results will guide the rational design of highly efficient and robust MgO-based adsorbent pellets for CO2 capture applications.

Effect of extrusion-spheronization granulation and manganese loading on catalytic ozonation of petrochemical wastewater.

The petrochemical secondary effluent (PSE) is typical refractory wastewater derived from the petrochemical industries, which requires advanced treatment due to the strict environmental protection policies. Catalytic ozonation is one of the most widely used advanced oxidation technologies in wastewater treatment because of its high mineralization rate, in which the alumina-based catalyst usually plays an important role. Extrusion-spheronization is a promising technique for the preparation of alumina spheres because the synthesized alumina particles have high sphericity, high specific surface aera and narrow particle size distribution. In this paper, two kinds of alumina-based catalysts (catalyst A: manganese nitrate added after alumina granulation and catalyst B: manganese nitrate added into alumina powder before granulation) were prepared by the extrusion-spheronization method and used for PSE treatment by catalytic ozonation. The prepared alumina samples were characterized by Brunauer-Emmett-Teller (BET) method, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and scanning electron microscopy (SEM), while the wastewater samples were analyzed for Total organic carbon (TOC), UV254 and fluorescence spectroscopy. Results showed that manganese was uniformly distributed in both catalysts, and the specific surface area of two catalysts was 318.36 m2/g and 354.95 m2/g, respectively. Catalytic ozonation experiments were repeated nine times with each catalyst under the same conditions. The TOC removal rates for catalysts A and B in the first run were 48.88% and 49.06%, respectively, then it dropped to 28.05% for catalyst A but remained 47.81% for catalyst B after using for nine times. This implied that the long-term performance of catalyst B would be more stable than catalyst A. Similar result were found in three-dimensional fluorescence analysis. UV254 results indicated that the removal efficiency of aromatic and unsaturated substances by catalyst B was higher than catalyst A. A possible explanation is that the active component manganese oxide formed a catalyst skeleton in catalyst B, which makes it hard to dissolve. Effect of extrusion-spheronization granulation and manganese loading on advanced oxidant treatment of petrochemical wastewater.

Design of Experiment Approach to Assess the Effect of Formulation Variables on Extrusion and Spheronization of Telmisartan and Cilostazol Loaded Pellets and its Pharmacokinetic Study

Background: Solubility is an important parameter that affects the availability of drug in systemic circulation. Drugs having poor solubility belonging to BCS class II eventually result in lower dissolution and bioavailability. Hence, improvement of solubility is a challenging task. Hence the present work focuses on using solid dispersion and inclusion complex approach for both telmisartan and cilostazol belonging to BCS Class II drugs. Objective: The present study was carried out to improve apparent solubility of telmisartan and cilostazol (BCS-Class II drugs) and optimization as pellets along with its pharmacokinetic study. Methods: Phase solubility study was carried out to screen the excipients such as, PVPK30, PVA, HPMC E5 and β-CD. Solvent evaporation method was adopted to prepare the solid dispersions and inclusion complex of both drugs. Pellets were optimized by extrusion spheronization method using 32 factorial design and characterized by morphology, drug content, DSC, FTIR, XRD, SEM, in- -vitro studies and drug content study. Results: Phase solubility study showed improved apparent solubility of telmisartan with HPMC E5 (1:3) by solid dispersion and cilostazol with β-CD (1:3) using inclusion complexation method. Drug characterization did not reveal any incompatibility. Formulation was optimized on the basis of acceptable pellet properties, including acceptable spherical shape and micromeritics properties. The percent friability of all batches was found to be less than 1%. The optimized pellets of both drugs prepared with micro crystalline cellulose provided desirable maximum release with acceptable release profile. Conclusion: The formulated pellets when studied in vivo showed superior pharmacokinetic profile. The drawback associated with apparent solubility and bioavailability of both drugs can thus be alleviated by use of novel pellet formulation.

Ni-CaO dual function materials prepared by different synthetic modes for integrated CO2 capture and conversion

Dual-functional materials (DFMs) present broad prospects in CO2 capture and in-situ conversion to value-added products using renewable energy. Herein, we proposed and demonstrated three different synthetic modes for preparing Ni-CaO DFMs using carbide slag as calcium precursor. CO2 sorption and in-situ hydrogenation performance of the Ni-CaO DFMs was evaluated using a fixed-bed reactor. Results indicated that CO2 sorption capacity and CO productivity of the synthesized Ni-CaO DFMs depended on the synthetic modes. The desired Ni/CS-P30-C synthesized by acid pretreatment of carbide slag followed by citric acid complex exhibited a high CO2 sorption capacity (13.28 mmol/g DFMs) and a great CO productivity (5.12 mmol/g DFMs) under the isothermal testing temperature of 650 °C. The sample also showed stable CO2 uptake and CO productivity within 17 cycles. The good CO2 sorption and in-situ hydrogenation performance were associated with the better textural properties, smaller particle size and more uniform dispersion of Ni species, which were resulted from propionic acid pretreatment and citric acid complex processes. In addition, Ni-CaO pellet with high mechanical strength (2.88 MPa) and abrasion ability (weight loss of 2.36% after 3000 rotations). had also been prepared by the extrusion-spheronization method. The pelletization process adversely affected the CO2 sorption and in-situ hydrogenation performance, but the pellet exhibited good stability in cyclic operations.

Preparation and preliminary quality evaluation of aspirin/L-glutamate compound pellets

L-glutamate is an important component of protein. It can prevent gastrointestinal damage caused by NSAIDs. We constructed two-phase enteric-coated granules of aspirin and L-glutamate compound by extrusion spheronization method and fluidized bed coating. The subliminal effective dose of L-glutamate is 100 mg/kg tested by model of gastric ulcer of rats induced by aspirin and drug administration. HPLC-UV and UV–Vis methods were adopted to determine content and cumulative release of aspirin and L-glutamate as quality analysis method indexes. The prescription and process optimization were carried out with yield, sphericity and dissolution. The two-phase compound granules have good sphericity of 0.93 ± 0.05 (aspirin pellets) and 0.94 ± 0.02 (L-glutamate pellets), content of salicylic acid (0.24 ± 0.03)%, dissolution of aspirin (2.36 ± 0.11)%. Quality evaluation and preliminary stability meet the commercial requirements. The stored environment of compound preparation should be sealed in a cool and dark place.