Aluminum Potassium Sulfate Dodecahydrate Research Articles

Effect of Lemon Waste Natural Dye and Essential Oil Loaded into Laminar Nanoclays on Thermomechanical and Color Properties of Polyester Based Bionanocomposites.

In this work, polyester-based nanocomposites added with laminar nanoclays (calcined hydrotalcite, HT, and montmorillonite, MMT) loaded with lemon waste natural dye (LD) and essential oil (LEO) were prepared and characterized. The optimal conditions to synthetize the hybrid materials were obtained by using statistically designed experiments. The maximum LD adsorption with HT was found using 5 wt% of surfactant (sodium dodecyl sulfate), 5 wt% of mordant (aluminum potassium sulfate dodecahydrate) and 50% (v/v) ethanol. For MMT, 10 wt% of surfactant (cetylpyridinium bromide), 5 wt% of mordant, 1 wt% of (3-aminopropyl) triethoxysilane and 100% distilled water were used. LEO adsorption at 300 wt% was maximized with MMT, 10 wt% of surfactant and 50 °C following an evaporation/adsorption process. The obtained hybrid nanofillers were incorporated in a polyester-based matrix (INZEA) at different loadings (3, 5, and 7 wt%) and the obtained samples were characterized in terms of thermal stability, tensile behavior, and color properties. HT_LEM-based samples showed a bright yellow color compared to MMT_LEM ones. The presence of lemon hybrid pigments in INZEA-based systems produced a remarkable variation in CIELAB color space values, which was more visible with increasing the nanofillers ratio. A limited mechanical enhancement and reduced thermal stability was observed with the nanopigments addition, suggesting a limited extent of intercalation/exfoliation of MMT and HT in the polymer matrix. MMT_LEM pigments showed higher thermal stability than HT_LEM ones. A significant increase in Young’s modulus of nanocomposites loaded with hybrid LEO was observed compared to the biopolymer matrix. The LEO inclusion into the nanoclays efficiently improved its thermal stability, especially for MMT.

Experimental and numerical study of modified expanded graphite/hydrated salt phase change material for solar energy storage

Solar thermal storage system has strict requirements on the problems of hydrated salt phase change materials (PCMs) such as supercooling, phase separation, low thermal conductivity and cyclic stability. In addition, the long-term storage/release heat cycle of PCMs lead to the loss of crystallization water and shorten the service life. Herein, we demonstrate an improved model to predict the thermal conductivity of modified carbon-based matrix form-stable PCMs based on the relationship between porosity (ε) and modified expanded graphite (MEG) content. The proposed new model may predict the thermal conductivity of carbon-based matrix composites with relatively high precision. Furthermore, the hydrophilic and hydrophobic groups on the surface of EG sheet have been rearranged via titanate coupling agent, and then MEG is introduced as high thermal conductivity porous matrix. The modified aluminum potassium sulfate dodecahydrate (MAPSD) is used as the PCM. Five different EG contents of MEG/APSD composite PCM samples with the same density have been prepared by the method of “melting blend-solidification and form-stable”. In addition, 80 times storage/release heat experiments are carried out on the samples and the heat transfer process of the three-dimensional (3D) model is numerically simulated. It results show that the weight loss of the composites with MEG samples decreased by only 7.85%. The simulation results suggest that the temperature field and phase change interface vary uniformly. Moreover, the composites samples with MEG has the superior heat transfer performance and much higher heat storage/release rate. With sample density 900 kg/m3 and the MEG content of 20 wt%, the MEG/APSD composites has relatively good thermal performance and high cost performance. Therefore, it can be applied for industrial waste heat energy recovery applications, the solar domestic hot water system and mid-temperature thermal energy storage system.

Preparation and thermal property analysis of a novel phase change heat storage material

Hydrated salt of aluminium potassium sulfate dodecahydrate (APSD)/expanded graphite (EG) form-stable composite phase change material (PCM) has been prepared. Hydrated salt of aluminium potassium sulfate dodecahydrate used as the PCM was firstly modified by using nucleator and thickener with the aiming at solving the supercooling and phase separation. Sulfurized EG is selected as supporting matrix to overcome leakage and low thermal conductivity of MAPSD. Furthermore, hydrophilic and hydrophobic groups on the surface of the expanded graphite is oriented by carrying out titanate coupling agent, which could restrict the volatilization of crystal water and solve the poor cyclic stability problems of APSD. The thermal performance of modified APSD (MAPSD) and modified EG (MEG)/MAPSD composite PCMs are tested and analyzed by using Differential Scanning Calorimeter (DSC), Hot Disk Thermal Constant Analyzer and a small-scale experimental device. The DSC analysis showed that the melting enthalpy of form-stable composite PCM containing 80 wt% APSD and MAPSD are 473.52 and 641.75 J/g, and their corresponding melting points are 84.39 and 84.34 °C, respectively. The 100 times melt-freeze cyclic tests revealed that the mass of MAPSD decreases by 45.57%. However, the mass of MEG/MAPSD composite PCMs decreases by only 7.91% when the sample density (ρ) of 900 kg/m3 and mass fraction of MEG with 20%, which could still maintain its original shape perfectly without any change. What’s more, the effective thermal conductivity of MEG/MAPSD composite PCM (6.157 W/(m·K)) is about 11 times higher than that of pure APSD (0.55 W/(m·K)) and Agari-Uno model is used to predict the thermal conductivity of composite PCMs with different MEG contents. The average deviation is only 3.91% between experimental and predicted value. All the results indicate that the form-stable MAPSD/MEG composite PCMs can be considered as high-performance latent heat storage materials and the great potential for practical application in solar thermal utilization.

Field efficacy of some products against the bacterial canker of kiwifruit in Emilia-Romagna Region, Italy

Within the Research Project on the bacterial canker of kiwifruit caused by Pseudomonas syringae pv. actinidiae (PSA) sponsored by Emilia-Romagna Region during the period 2012-2015, the results of 4 trials in open field conditions - in presence of natural inoculum - to verify the efficacy of different active ingredients to control the disease are presented. The field trials confirmed previous studies on the efficacy of copper-based products and acibenzolar-S-methyl. A formulation of poliglucosammine and a formulation which combines the action of poliglucosammine with copper and boron contributed to reduce disease symptoms too. An inorganic compound based on aluminum potassium sulfate dodecahydrate confirmed in open field the good results showed in vitro and in greenhouse assays. These results give good indication for the PSA management with copper and acibenzolar-S-methyl, while further studies to confirm the activity of the new compounds presented in this study are needed.

Solidification/stabilization of stainless steel pickling residue with aluminum potassium sulfate amended fly ash

This article presents an original study on the feasibility of reuse fly ash (FA) solidified/stabilized stainless steel pickling residue (SSPR). SSPR was characterized using different leaching procedure and solidified/stabilized using aluminum potassium sulfate dodecahydrate (KAl(SO4)2.12H2O) amended fly ash. A modified four-step Community Bureau of Reference (BCR) sequential leaching test and risk assessment code (RAC) was employed to evaluate the potential hazards of metals in SSPR. Results show that SSPR mainly consists of sulfates and heavy metals. The major elements are Ca and Fe, with the total amount of 191,600 and 122,400 mg/kg. Cr is the most notable metal with a total amount of 22,500 mg/kg. Its concentrations in HJ/T 299 and HJ/T 300 extracts are 28.6 and 285 mg/L respectively. Another metal that is of some concern is Ni, its concentration in HJ/T 300 extract is 229 mg/L and total content in the residues is 10,690 mg/kg. The RAC of four list heavy metals are: Ni (61.36%) > Zn (43.48%) > Cr (20.64%) > Cu (19.83%). Therefore, SSPR has a higher potential to be hazardous to the environment. After treatment by 10% of KAl(SO4)2.12H2O with 40% of FA2 (10KA40FA2), the concentration of Cr is 7.9 mg/L in HJ/T 299 extract and 12.68 mg/L in HJ/T 300 extract. While these two values for Ni is 0 and 14.34 mg/L. The RAC of the metals after treatment by 10KA40FA2 followed the order of Ni (20.38%) > Zn (10.59%) > Cu (8.54%) > Cr (7.71%). The unconfined compression strength (UCS) tests showed that the 7-d UCS of the 10KA40FA2 remolded sample achieved 3556.2 kPa which was much higher than that of raw SSPR remolded sample of 1746.7 kPa.

Experimental investigations of Alum/expanded graphite composite phase change material for thermal energy storage and its compatibility with metals

A novel composite phase change material(CPCM) were prepared with Aluminum potassium sulfate dodecahydrate(Alum, KAl(SO4)2·12H2O) as PCM and expanded graphite(EG) as nucleating agent and porous matrix for thermal conductivity enhancing. The detailed thermo-physical properties and thermal energy storage performance were studied. The DSC revealed that the melting temperature and latent heat of fusion of Alum/EG CPCM were 87.92 °C and 214.9J/g, respectively. The thermal conductivity of Alum/EG CPCM was improved from 0.497W·m−1·K−1 to 5.875W·m−1·K−1 due to the addition of EG, which can also be confirmed by the infrared thermal imager during charging/discharging process. The Alum/EG CPCM exhibited prominent chemical stability and thermal reliability before and after 500 thermal cycle tests. Furthermore, the corrosion of three metals and one metal alloy were studied and the gravimetric analysis and the results of element composition of four samples exhibited that the brass was the suitable materials for the container for long-term used while stainless steel 304L and aluminum were severely corroded. The results demonstrated that Alum/EG CPCM was a prospective candidate for thermal energy storage and accelerated the research on the Alum/EG heat storage system.

Investigating the effect of graphene nanoplatelets on the thermal conductivity of KAl(SO4)2 · 12H2O

This article, taking phase change material (PCM) aluminum potassium sulfate dodecahydrate (KAl(SO4)2 · 12H2O) as the object of study, researches the effects of graphene nanoplatelets (GN) on the thermal conductivity of KAl(SO4)2 · 12H2O. Correlated analysis shows that KAl(SO4)2 · 12H2O can be combined with GN to form KAl(SO4)2 · 12H2O/GN composites. The thermal conductivity of KAl(SO4)2 · 12H2O/GN composites improves significantly with the increase of GN contents. When the content of GN up to 2.5 wt%, the thermal conductivity of the composites is 1.311 W/m · k, increasing by 120% compared with the pure KAl(SO4)2 · 12H2O, the thermal storage time reduces by 31.9%. Meanwhile, GN can improve the undercooling of KAl(SO4)2 · 12H2O. When the content of GN is 2.5 wt%, the minimum undercooling is 31.1 °C, reducing by 28.5% compared with the pure KAl(SO4)2 · 12H2O. X-ray diffractometry (XRD) analysis shows that the crystal structure of KAl(SO4)2 · 12H2O is basically unchanged with the composite of GN after circulation. In general, GN have a great effect on improving the thermal conductivity of KAl(SO4)2 · 12H2O and have a good application prospect in the field of phase change thermal storage.

Preparation and Characterization of NiMo/Al2O3Catalyst for Hydrocracking Processing

Hydrocracking is a chemical process used in petroleum refineries for converting high boiling hydrocarbons in petroleum crude oils to more valuable lower boiling products such as gasoline, kerosene, and diesel oil that operate at high temperature and pressure. Catalyst was used in hydrocracking to reduce temperature and pressure. Hydrocracking catalyst are composed of active components and support. Alumina is widely used in hydrocracking process as catalyst support due to its high surface area, high thermal stability, and low prices. The objective of this research was preparated NiMo/Al2O3 catalyst that used as hydrocracking catalyst. Catalyst was synthesized by wetness impregnation method and simple heating method with various kind of Al2O3. The physicochemical properties of catalyst were investigated by X-ray diffraction (XRD) to determine type of crystal and scanning electron microscopy (SEM) to determine morphology of the catalyst. The NiMo/Al2O3 catalyst prepared by aluminium potassium sulfate dodecahydrate exhibited the highest crystallinity of 90.23% and it is clear that MoO3 and NiO crystallites are highly dispersed on the NiMo/Al2O3 catalyst which indicates as the best catalyst. The catalytic activity in hydrocracking process was successfully examined to convert fatty acid into hydrocarbon.

Extraction and characterization of lignin from oil palm biomass via ionic liquid dissolution and non-toxic aluminium potassium sulfate dodecahydrate precipitation processes

The objective of this study is to extract and characterize lignin from oil palm biomass (OPB) by dissolution in 1-butyl-3-methylimidazolium chloride ([bmim][Cl]), followed by the lignin extraction through the CO2 gas purging prior to addition of aluminum potassium sulfate dodecahydrate (AlK(SO4)2·12H2O). The lignin yield, YL (%wt.) was found to be dependent of the types of OPB observed for all precipitation methods used. The lignin recovery, RL (%wt.) obtained from CO2-AlK(SO4)2·12H2O precipitation was, however dependent on the types of OPB, which contradicted to that of the acidified H2SO4 and HCl solutions of pH 0.7 and 2 precipitations. Only about 54% of lignin was recovered from the OPB. The FTIR results indicate that the monodispersed lignin was successfully extracted from the OPT, OPF and OPEFB having a molecular weight (MW) of 1331, 1263 and 1473g/mol, and degradation temperature of 215, 207.5 and 272°C, respectively.

Formation of Microcapsulated Aluminium Potassium Sulfate Dodecahydrate by Phase Separation Method

The aim of this study was to produce microencapsulated phase change materials (PCMs) by simple coacervation method. For PCM KAl(SO4)2.12H2O (Alum) and for coating ethyl cellulose (EtC) and poly(methyl methacrylate) (PMMA) were selected. The spherical core particles of 1.25 – 2 mm size were prepared by pan granulation of Alum-water wet pellets. Shell coating was carried out by two different types of coacervation variants. Process I: EtC polymer coacervation was induced from cyclohexane solution reducing the temperature from 81 °C to 25 °C. The polymer shell on the Alum particles surface was incomplete, because during hardening the polymer coatings was shrunken. Process II: Formation of EtC and PMMA shell coating was induced on Alum core surface by solvent change method. The polymer shell was coacervated from their dichloromethane solution by hexane. The water permeability, i. e. the release of Alum was investigated by conductivity measurements.

<i>In Situ</i> Observation of Diamagnetic Fluid Flow in High Magnetic Fields

The effect of high magnetic field on diamagnetic fluid flow has been studied by in-situ optical observation. The Schlieren optics utilizable under high magnetic fields was developed to carry out in-situ observation of the behavior of feeble magnetic fluids. Using a crystal of the diamagnetic aluminum potassium sulfate dodecahydrate, the behavior of the downward flow of high concentration solution in the sample dissolution process was observed. It was found that the direction of diamagnetic fluid flow was changed under spatially varied magnetic field. This phenomenon was understood qualitatively by considering the magnetic force acting on the high concentration solution and the surrounding solution.

Effect of Hot Water and Water-carrying Agent on the Properties of Silane-water Crosslinked Linear Low Density Polyethylene

Abstract The influence of hot water and the water-carrying agent aluminum potassium sulfate dodecahydrate (alum) on the mechanical and thermal properties of the silane-water crosslinked linear low density polyethylene (LLDPE) was investigated. LLDPE was melt-grafted with various content of vinyl trimethoxysilane (VTMS) using dicumyl peroxide (DCP) as initiator. The results show that the contribution of hot water to gel content is poor, about 2 to 16%, compared with that of the silane grafted LLDPE. Is feasible to achieve silane-water crosslinking reaction with alum for self-crosslinked LLDPE; furthermore, the self-crosslinked LLDPE has lower crosslink density (ν). It was found that alum could not only conduct silane-water crosslinking reaction effectively, but also improve the mechanical properties, especially the elongation behavior. The heat of fusion (ΔHm), the melting temperature (Tm), and the degree of crystallinity (Xc) of the hot water crosslinked LLDPE decreased with the advancement of VTMS. The Avrami exponent n of self-crosslinked sample was larger than that of hot water crosslinked sample. This means that the alum could contribute to the growth of crystallization.

An eco-friendly and efficient route of lignin extraction from black liquor and a lignin-based copolyester synthesis

Traditional method for extraction of lignin from black liquor in chemical pulping processes requires a huge amount of toxic inorganic acids like sulfuric acid which are potentially harmful to our environment and life. Furthermore, the traditional method always contains multiple steps, and thus it is time-consuming process. With a purpose to eliminate all these above disadvantages, in this study, we successfully developed an efficient process for the extraction of lignin from black liquor using a non-toxic aluminum potassium sulfate dodecahydrate (AlK(SO4)2·12H2O). The developed process is simple, efficient, and short-time, which obviously have more advantages over the traditional extraction method. Furthermore, the lignin extracted in this study was used to synthesize a copolyester through polyesterification between lignin and sebacoyl chloride. The copolymer possesses a molecular weight of 31,800, corresponding to four to five repeating units of lignin macromonomers. Notably, it showed a good thermal stability up to 200 °C in TGA analysis. It was also possible to shape the copolymer using solvent casting. We believe that this newly developed method of lignin extraction may exploit new applications for eco-friendly sustainable materials in various fields.

Synthesis and characterization of polyurethane-coated palygorskite

Palygorskite was coated with polyurethane latex with aluminium potassium sulfate dodecahydrate as demulsifying agent. The coating was proofed by Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TG) and transmission electron microscopy (TEM). The thermogravimetric analysis indicated that the mass content of polyurethane was 9%. Transmission electron microscopy observation revealed that the coating was about 10 nm thick.

Reduction of house-dust mite allergen concentrations in carpets by aluminium potassium sulfate dodecahydrate (alum)

Special tools and skilled labor are required to reduce house-dust mite allergens in carpets. The main house-dust mite allergen is Der p 1, a soluble protein found in high abundance in woolen carpets. Current chemical treatment options are either unsafe or ineffective in eradicating Der p 1. Here, we present an effective, safe, and easy application reagent to reduce the allergen levels in carpets. Sixty woolen carpets with Der p 1 concentrations >2 microg/g in fine dust were divided into three homogeneous groups of 20 carpets each, according to their allergen load. We tested alum dissolved in 60 mL of water at doses of 3, 6, and 9 g/m2 against Der p 1 in groups 1, 2, and 3, respectively. The test side of the carpets was sprayed with the reagent. The control side was treated with the 60 mL of tap water. Dust particles were collected from a 1-m2 area on each carpet side 24 hours after treatment and were analyzed for Der p 1 content with a monoclonal ELISA. Alum reduced the Der p 1 concentrations by 48.6 +/- 6.2%, 78.8 +/- 7.2%, and 95.2 +/- 3.0% at 3, 6, and 9 g/m2 in the carpets, respectively. Moreover, there were no complaints registered by the residents against the alum applications. Alum, at 9 g/m2 (in a solution at 15%) in water, can be used for decreasing existing Der p 1 concentrations in woolen carpets.

Recto-vaginal fistula following coitus: an aftermath of vaginal douching with aluminium potassium sulphate dodecahydrate (potassium alum)

This report delineates an incident of coital injury following douching of vagina with aluminum potassium sulfate dodecahydrate (potassium alum) which is believed to promote greater sexual stimulation of the husband during sexual intercourse. A 28-year-old woman was admitted to the gynecological ward complaining of vaginal pain bleeding and passage of fecal matter through the vagina after douching it with potassium alum prior to coitus. Vaginal examination showed a lot of fecal matter with a septic edematous wound 2.5 cm at the fourchette a fistula about 5 cm in length. Treatment included daily perineal toileting a low residue diet antibiotics and advice against vaginal douching with potassium alum.

Aluminum potassium sulfate dodecahydrate solubility in mixed dipotassium sulfate + aluminum sulfate solutions

Recently, the Pitzer interaction model was used to calculate aluminium potassium sulfate dodecahydrate solubility products from published solubility data. The model preformed poorly, reflected by a marked increase in values with decreasing solution potassium content. Solubility measurements at 25 o C were repeated in this study

Secondary Nucleation Rate of Aluminum Potassium Sulfate Dodecahydrate

Secondary Nucleation Rate of Aluminum Potassium Sulfate Dodecahydrate