scholarly journals PREPARATION OF CALCIUM SULFATE HEMIHYDRATE WHISKERS FROM COMPLEX JAROSITE WASTE

2021 ◽  
Vol 55 (3) ◽  
Author(s):  
Hongbin Tan ◽  
Xiaoling Ma ◽  
Faqin Dong ◽  
Yufeng Li ◽  
Jinming Wang ◽  
...  
Keyword(s):  
Aspect Ratio ◽  
Calcium Sulfate ◽  
Raw Materials ◽  
Tap Water ◽  
Large Diameter ◽  
Raw Material ◽  
Iron Sulfate ◽  
Impurity Ions ◽  
Ammonium Jarosite ◽  
Calcium Sulfate Hemihydrate

Complex jarosite waste was obtained from zinc metal hydrometallurgical process, which contained gypsum and ammonium jarosite (NH4Fe3(SO4)2(OH)6). The influence of impurity ions (Fe3+ and NH4+) on the calcium sulfate hemihydrate (HH) morphology was studied using pure gypsum as the raw material, respectively. HH crystals with a high aspect ratio were obtained without the impurity ions. The diameter increased and the aspect ratio of the HH decreased, while the addition of iron sulfate and ammonia sulfate increased. Ammonium iron (NH4+) can be removed by using calcium oxide to decompose the ammonium jarosite in the waste and then to wash the sediment with tap water. The sediment (calcified jarosite sediment) mainly contained CaSO4·2H2O and Fe(OH)3. The influence of cultivating time on HH crystals growth was researched by using the sediment as raw materials. The diameter of the whiskers increased, while the hydrothermal time increased. The whiskers were obtained, with high a aspect ratio (10–60), large diameter (1–4 µm) and smooth surface, after the sediment was treated at 140 °C for 6 h in pH = 5 solution.

Preparation of anhydrite from eggshell via pyrolysis

2018 ◽  
Vol 7 (2) ◽  
pp. 139-146 ◽  
Author(s):  
Nuchnapa Tangboriboon ◽  
Wanitcha Unjan ◽  
Watchara Sangwan ◽  
Anuvat Sirivat
Keyword(s):  
Calcium Sulfate ◽  
Pore Diameter ◽  
Raw Materials ◽  
Raw Material ◽  
X Ray ◽  
Anhydrous Calcium Sulfate ◽  
Calcium Sulfate Dihydrate ◽  
Thermal Analyzer ◽  
Infrared Spectrometer ◽  
Calcium Sulfate Hemihydrate

AbstractCalcium sulfate dihydrate (CaSO4·2H2O) was prepared from the chemical reaction between calcium carbonate from duck eggshell and sulfuric acid at 25°C. The CaSO4·2H2O was dried in an oven at 110°C and transformed into calcium sulfate hemihydrate or plaster of Paris (CaSO4·0.5H2O). The CaSO4·0.5H2O was calcined at 700, 800 and 900°C and transformed into anhydrite or anhydrous calcium sulfate (CaSO4). The raw material used in this research was the duck eggshell, the waste eggshell generated from food processing industries. The obtained anhydrous calcium sulfate or anhydrite has true density, color, specific surface area, pore diameter and particle size equal to 2.95 g/cm3, white powder, 3.57 m2/g, 96.98 Å and 3.983 μm, respectively. In addition, other characteristics, microstructures, phase transformation and physical properties of raw materials and calcium sulfates were investigated and reported here using X-ray fluorescencemeter, Fourier transform infrared spectrometer, differential thermal analyzer, thermogravimetric analysis, scanning electron microscope, X-ray diffractometer, pycnometer method and Brunauer-Emmett-Teller.

A Modification of Spherical Particles Calcium Sulfate for Alveolar Bone Defect

2013 ◽  
Vol 377 ◽  
pp. 199-203
Author(s):  
Xiao Pei Wu ◽  
Wei Bo Zhu ◽  
Duan Cheng Wang ◽  
Qing Hua Chen
Keyword(s):  
Calcium Sulfate ◽  
Degradation Rate ◽  
Alveolar Bone ◽  
Raw Material ◽  
Spherical Particles ◽  
Crystal Binding ◽  
Ft Ir ◽  
Alveolar Bone Defect ◽  
Surface Crystal ◽  
Calcium Sulfate Hemihydrate

Calcium sulfate hemihydrate has been used for many years as a biomaterial. However, too fast a degradation rate and lack of bioactivity have limited its application in orthopaedic field. Herein, α-Calcium sulfate hemihydrate is used as the raw material to prepare spherical particles calcium sulfate with stir method. Microstructures, degradation, and bioactivity of the materials were characterized by XRD, FT-IR and SEM. The effects of solutions of sodium silicate (Na2SiO3) on the structure and properties of the materials were analyzed. The results indicate that both the interface structure and the surface crystal binding state of the spherical particles calcium sulfate are changed by the solutions. The bioactivity was significantly improved by the solutions of Na2SiO3. With increasing the concentration of solutions in the materials, the degradation rate of the materials is decreased. Si-O network membrane which contains a large amount of Si-OH was formed on the surface of calcium sulfate. Therefore, the degradation rate was decreased and the bioactivity was significantly improved.

Upgrading of Waste Gypsum for Building Materials

2018 ◽  
Vol 766 ◽  
pp. 211-216 ◽  
Author(s):  
Piyalak Ngernchuklin ◽  
Nestchanok Yongpraderm ◽  
Arjin Boonruang ◽  
Sittichai Kanchanasutha ◽  
Pracha Laoauyporn ◽  
...  
Keyword(s):  
Calcium Sulfate ◽  
Building Materials ◽  
Bending Strength ◽  
Raw Material ◽  
Washing Process ◽  
Waste Gypsum ◽  
Ph Scale ◽  
Relationship Of ◽  
The Relationship ◽  
Calcium Sulfate Hemihydrate

In this research, waste gypsum (CaSO4·2H2O), a by-product material from industrial factory, was upgraded and then used as raw material for building materials. The by-product gypsum possessed a high acidic value of 3-point pH scale and moisture content of 40 %. The two properties had an impact on setting reaction and hardening of gypsum. Therefore, the studies of gypsum phase transformation to calcium sulfate hemihydrate (CaSO4·0.5H2O) were focused on washing process and amount of calcium carbonate (CaCO3) added at 0, 1, 3 and 5 % wt. After washing, waste gypsum and washed water were reduced from high acidic value to neutralization (pH = 7) as a result of CaCO3. Next, the neutralized gypsum was heated to the optimal temperature at 160 °C for 2 hours and transformed to hemihydrate gypsum phase observed by XRD. Finally, the relationship of amount of CaCO3-mechanical property such as bending strength will be investigated.

Effects of sterilization modes on the mechanical strengths of plaster of paris implants

1989 ◽  
Vol 47 ◽  
pp. 890-891
Author(s):  
K. Cowden ◽  
B. Giammara ◽  
T. Devine ◽  
J. Hanker
Keyword(s):  
Gamma Radiation ◽  
Calcium Sulfate ◽  
Significant Loss ◽  
Potassium Sulfate ◽  
Limiting Factors ◽  
Radiation Sterilization ◽  
Plaster Of Paris ◽  
Hardness Tester ◽  
Dry Heat ◽  
Calcium Sulfate Hemihydrate

Plaster of Paris (calcium sulfate hemihydrate, CaSO4. ½ H2O) has been used as a biomedical implant material since 1892. One of the primary limiting factors of these implants is their mechanical properties. These materials have low compressive and tensile strengths when compared to normal bone. These are important limiting factors where large biomechanical forces exist. Previous work has suggested that sterilization techniques could affect the implant’s strength. A study of plaster of Paris implant mechanical and physical properties to find optimum sterilization techniques therefore, could lead to a significant increase in their application and promise for future use as hard tissue prosthetic materials.USG Medical Grade Calcium Sulfate Hemihydrate Types A, A-1 and B, were sterilized by dry heat and by gamma radiation. Types A and B were additionally sterilized with and without the setting agent potassium sulfate (K2SO4). The plaster mixtures were then moistened with a minimum amount of water and formed into disks (.339 in. diameter x .053 in. deep) in polyethylene molds with a microspatula. After drying, the disks were fractured with a Stokes Hardness Tester. The compressive strengths of the disks were obtained directly from the hardness tester. Values for the maximum tensile strengths σo were then calculated: where (P = applied compression, D = disk diameter, and t = disk thickness). Plaster disks (types A and B) that contained no setting agent showed a significant loss in strength with either dry heat or gamma radiation sterilization. Those that contained potassium sulfate (K2SO4) did not show a significant loss in strength with either sterilization technique. In all comparisons (with and without K2SO4 and with either dry heat or gamma radiation sterilization) the type B plaster had higher compressive and tensile strengths than that of the type A plaster. The type A-1 plaster however, which is specially modified for accelerated setting, was comparable to that of type B with K2SO4 in both compressive and tensile strength (Table 1).

RHEOLOGICAL PROPERTIES OF CERAMIC MASSES: IMPROVEMENT BY COMPLEX MATERIAL ACTIVATION

2019 ◽  
Vol 16 (3) ◽  
pp. 334-351
Author(s):  
A. S. Mavlyanov ◽  
E. K. Sardarbekova
Keyword(s):  
Rheological Properties ◽  
Raw Materials ◽  
Sensitivity Coefficient ◽  
Raw Material ◽  
Clay Material ◽  
Fibrous Materials ◽  
Chemical Production ◽  
Production Wastes ◽  
Pass Through ◽  
The Masses

Introduction. The objective of the research is to study the effect of the complex activation of the alumina raw material on the rheological properties of the ceramic mass. In addition, the authors investigate solutions for the application of optimal coagulation structures based on loams and ash together with plastic certificates.Materials and methods. The authors used the local forest like reserves of clay loams at the BashKarasu, ash fields of the Bishkek Central Heating Centre (BTEC) and plasticizer (sodium naphthenate obtained from alkaline chemical production wastes) as fibrous materials. Moreover, the authors defined technological properties of raw materials within standard laboratory methodology in accordance with current GOSTs.Results. The researchers tested plastic durability on variously prepared masses for the choice of optimal structures. The paper demonstrated the plastic durability of complexly activated compounds comparing with non-activated and mechanically activated compounds. The sensitivity coefficient increased the amount of clay loams by mechanically and complexly activated, which predetermined the possibility of intensifying the process of drying samples based on complexly activated masses.Discussion and conclusions. However, mechanical activation of clay material reduces the period of relaxation and increases the elasticity coefficient of ceramic masses by 1.8–3.4 times, meanwhile decreases elasticity, viscosity and the conventional power during molding, which generally worsens the molding properties of the masses. Сomplex activation of ash-clay material decreases the period of relaxation and provides an increase in elasticity, plasticity of ceramic masses by 46–47%, reduction in viscosity by 1.5–2 times, conventional power on molding by 37–122% in comparison with MA clay loams. Ceramic masses based on spacecraft alumina raw materials belong to the SMT with improved rheological properties; products based on them pass through the mouthpiece for 5–7 seconds.

ANALYSIS FOR POTENCY AND PRODUCTION OF GRANULE ORGANIC FERTILIZER BASED ON MANURE

2018 ◽  
Vol 7 (2) ◽  
Author(s):  
Firman L. Sahwan
Keyword(s):  
Organic Material ◽  
Organic Materials ◽  
Raw Materials ◽  
Organic Fertilizer ◽  
Raw Material ◽  
Cow Manure ◽  
Production Potential ◽  
Natural Organic Material ◽  
Very High

Organic materials that are generally used as raw material for organic fertilizer granules (POG) is a natural organic material that has been degrade, smooth and dry. One of the main raw materials are always used with a very high percentage of usage, is manure. Manure potential in Indonesia is very high, amounting to 113.6 million tons per year, or 64.7 million tons per year to the island of Java. From this amount, it will be generated numbers POG production potential of 17.5 million tons per year (total Indonesia) or 9.9 million tons per year for the island of Java. While the realistic POG production predictions figures made from raw manure is 2.5 million tons annually, a figure that has been unable to meet the number requirement of POG greater than 4 million tons per year. Therefore, in producing POG, it should be to maximize the using of the potential of other organic materials so that the use of manure can be saved. With the use of a small amount of manure (maximum 30% for cow manure), it would be useful also to avoid the production of POG with high Fe content.keywods: organic material, manure, granule organic fertilizer

Nutritional Value Research of Spelt Pasta with Vegetable Additives

Food Industry ◽  
2020 ◽  
Vol 5 (2) ◽  
pp. 61-70
Author(s):  
Oliya Fazullina ◽  
Stanislav Smirnov
Keyword(s):  
Dietary Fiber ◽  
Nutritional Value ◽  
Raw Materials ◽  
Health Indicators ◽  
Dietary Treatment ◽  
Raw Material ◽  
Whole Wheat ◽  
Healthy Nutrition ◽  
Physiologically Active Substances ◽  
Simple Carbohydrates

Health indicators of the population depend significantly on the food quality and nutritional value. Simple carbohydrates excess of and lack of protein, dietary fiber, vitamins, minerals, antioxidants and other physiologically active substances increase the risk of socially significant disease progress. The development and production of mass-consumed products with high nutritional and biological value, including affordable non-traditional raw materials use, are promising areas of the food industry development aimed at improving the nutritional status of the population. The article presents the research results on the developed Noodle products recipes from non-traditional raw materials that meet modern healthy nutrition requirements, intended for dietary treatment and dietary prevention of people with overweight / obesity. The research aimed at expanding the range of macaroni products with these characteristics. As the main raw material, a man selected whole-wheat flour – new spelt flour, and as additional raw materials – buckwheat flour, broccoli and celery powders. The researchers found that the introduction of macaroni products from buckwheat spelt, broccoli and celery powders into the recipe had a multidirectional effect, reducing or increasing various indicators of its nutritional value. The changes range did not affect the overall characteristics. The satisfaction degree of the average daily need for food substances and energy when consuming a portion of 100 g for each sample of developed Noodle products allows them to be classified as functional products that are protein and dietary fiber sources, according to the requirements of the TR CU 022/2011.

UNIDO, Industrial Processing of Natural Resources. New York: United Nations. 1981. viii + 78pp.US $ 5.00. [United Nations Publication Sales No. E. 81. 11 . B.1]

1982 ◽  
Vol 21 (4) ◽  
pp. 329-333
Author(s):  
Rashid Aziz
Keyword(s):  
New York ◽  
United Nations ◽  
Industrial Development ◽  
Raw Materials ◽  
Developed Countries ◽  
Raw Material ◽  
Industrial Processing ◽  
Depth Study ◽  
Manufactured Exports ◽  
Year 2000

The book under review is a concise but fairly in-depth study of the prospects for export diversification from the Less Developed Countries (henceforth labeled as LDCs) particularly to Developed Countries (henceforth labeled as OCs). Given the multiple problems faced by the LOCs in exporting to the OCs - protectionist policies with regards to manufactured exports, volatility of prices obtained for raw material exports, etc. - the study analyses the potential for following an intermediate route. The important issues in the export of semi -processed and wholly processed raw materials are discussed. 111ese issues range from the problems and potentials for the location of processing facilities in the LOCs to the formulation of appropriate policies to encourage an export of processed goods rather than raw materials. Such policies will be useful both in solving the balance of-payments problems of the LDCs and in attaining the goal of the Lima Declaration and Plan of Action on Industrial Development and Co-operation, that called for 2S percent of world industrial production to be located in the LOCs by the year 2000.

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