Chemistry of the Acid Neutralization Capacity of Bauxite Residue

2009 ◽  
Vol 26 (5) ◽  
pp. 873-881 ◽  
Author(s):  
Sameer Khaitan ◽  
David A. Dzombak ◽  
Gregory V. Lowry
Keyword(s):  
Bauxite Residue ◽  
Acid Neutralization ◽  
Neutralization Capacity ◽  
Acid Neutralization Capacity

scholarly journals The Physico-Chemical and Mineralogical Characterization of Mg-Rich Synthetic Gypsum Produced in a Rare Earth Refining Plant

2021 ◽  
Vol 13 (9) ◽  
pp. 4840
Author(s):  
Fatai Arolu Ayanda ◽  
Mohd Firdaus Mohd Anuar ◽  
Syaharudin Zaibon ◽  
Shamshuddin Jusop
Keyword(s):  
Rare Earth ◽  
Acid Soils ◽  
Acid Neutralization ◽  
Mineralogical Characterization ◽  
X Ray ◽  
Neutralization Capacity ◽  
Acid Neutralization Capacity ◽  
Refining Plant ◽  
Calcium Magnesium

The physical, chemical and mineralogical characterization of the constituents of magnesium-rich synthetic gypsum produced in a rare earth-refining plant located in Gebeng, Pahang, Malaysia was conducted through elemental chemical analysis, scanning electron microscopy with Energy Dispersive X-ray (EDX)-analyzer, thermal analysis, X-ray fluorescence and X-ray diffraction. The crystalline nature of the by-product was studied using FTIR spectroscopy. Elemental analysis confirmed the presence of Ca and Mg, which are essential macronutrients required by plants and this Ca alongside the high pH (9.17) of MRSG may confer on the material a high acid neutralization capacity. From the result, it was observed that the studied by-product is a heterogeneous crystalline material comprising of gypsum (CaSO4.2H2O) and other major components such as calcium (magnesium) compounds (hydroxide, oxide, silicates, and carbonate) and sulfur. These aggregates may contribute to give an acid neutralization capacity to MRSG. The XRD study of MRSG indicated a high content of gypsum (45.4%), shown by the d-spacing of 7.609 Å (2-theta 11.63) in the diffractogram. The infrared absorption spectra of MRSG indicate close similarities to mined gypsum. The results of the characterization indicated that MRSG has valuable properties that can promote its use in amending soil fertility constraints on nutrient-deficient tropical acid soils.

An evaluation of waste gypsum-based precipitated calcium carbonate for acid mine drainage neutralization

2012 ◽  
Vol 65 (9) ◽  
pp. 1577-1582 ◽  
Author(s):  
J. N. Zvimba ◽  
J. Mulopo ◽  
L. T. Bologo ◽  
M. Mathye
Keyword(s):  
Acid Mine Drainage ◽  
Mine Drainage ◽  
Acid Neutralization ◽  
Precipitated Calcium Carbonate ◽  
X Ray ◽  
Neutralization Capacity ◽  
Acid Neutralization Capacity ◽  
Acid Mine ◽  
Waste Gypsum ◽  
Major Oxide

Precipitated CaCO3 compounds recovered from pulped waste gypsum using some carbonate and hydroxide-based reagents were evaluated for their utilization in acid mine drainage (AMD) neutralization. The neutralization potentials, acid neutralization capacities and compositions of the CaCO3 compounds were determined and compared with some commercial CaCO3. It was observed that CaCO3 recovered from waste gypsum using Na2CO3 significantly neutralized AMD compared with commercial CaCO3 and that recovered using both (NH4)2CO3 or NH4OH-CO2 reagents. Moreover, a higher acid neutralization capacity of 1,370 kg H2SO4/t was determined for CaCO3 recovered from waste gypsum using Na2CO3 compared with an average of 721 and 1,081 kg H2SO4/t for ammonium-based CaCO3 and commercial CaCO3 respectively. The inorganic carbon content for the CaCO3 recovered using Na2CO3 and ammonium-based reagents of 49 and 34% respectively confirmed their observed neutralization potentials and acid neutralization capacities, while energy dispersive X-ray fluorescence suggested absence of major oxide impurities, with the exception of residual SO42− and Na2O which still requires further reduction in the respective compounds.

scholarly journals Formulation, Development and Evaluation of Chewable Bi-layered Tablets for Treating Gastro Esophageal Reflux Disease

2020 ◽  
Vol 10 (4-s) ◽  
pp. 92-99
Author(s):  
Ankur Vasoya ◽  
Sunil Kumar Shah ◽  
C K Tyagi ◽  
Prabhakar Budholiya ◽  
Harish Pandey
Keyword(s):  
Calcium Carbonate ◽  
Drug Release ◽  
Sodium Bicarbonate ◽  
Sodium Alginate ◽  
Acid Neutralization ◽  
In Vitro Drug Release ◽  
Neutralization Capacity ◽  
Acid Neutralization Capacity ◽  
Bilayer Tablets

The purpose of this research work was to formulate raft-forming chewable bilayer tablets of sodium alginate using a raft-forming agent along with gas-generating agents. Tablets were prepared by wet granulation and evaluated for raft strength, acid neutralization capacity, weight variation, % drug content, thickness, hardness, friability and in vitro drug release. Various raft-forming agents were used in preliminary screening. The amount of sodium alginate, amount of calcium carbonate and amount sodium bicarbonate were selected as variables. Raft strength, acid neutralization capacity and drug release at 30 min were selected as responses.Tablets containing sodium alginate were having maximum raft strength as compared with other raft-forming agents. Acid neutralization capacity and in vitro drug release of all factorial batches were found to be satisfactory. Prepared tablets were found to be pharmaceutically equivalent to the marketed product. It was concluded that raft-forming chewable bilayer tablets prepared using an optimum amount of sodium alginate, calcium carbonate and sodium bicarbonate could be an efficient dosage form in the treatment of gastro oesophageal reflux diseases. Keywords: Chewable bilayer tablet, Sodium alginate, Raft forming agent, Acid Neutralizing capacity

scholarly journals Acid neutralizing capacity, an important waste management parameter

2020 ◽  
Vol 2 (2) ◽  
pp. 166-169
Author(s):  
Georgiana Cernica ◽  
◽  
Gina Alina Catrina ◽  
Georgeta Madalina Arama ◽  
Agnes Serbanescu ◽  
...  
Keyword(s):  
Waste Management ◽  
Industrial Waste ◽  
Acid Neutralizing Capacity ◽  
Acid Neutralization ◽  
Essential Information ◽  
Neutralization Capacity ◽  
Acid Neutralization Capacity ◽  
Successful Method ◽  
Neutralizing Capacity

The paper presents the influence of acid neutralization capacity in industrial waste samples as a decision indicator. For the analysis of the acid neutralization capacity, six samples of wastes from different sectors of activity were subjected. A successful method that can be applied to determine the properties of waste is acidneutralizing capacity. The acid-neutralizing capacity was evaluated with HCl 1 N by neutralizing the excess with NaOH 0.5 N after 15 min stirring. From the results obtained it is found that the acid neutralization capacity can provide essential information for the subsequent management of the waste.

scholarly journals Acid neutralization capacity measurements in surface and ground waters in the Upper River Severn, Plynlimon: from hydrograph splitting to water flow pathways

1997 ◽  
Vol 1 (3) ◽  
pp. 687-696 ◽  
Author(s):  
C. Neal ◽  
T. Hill ◽  
S. Hill ◽  
B. Reynolds
Keyword(s):  
Water Flow ◽  
Chemical Weathering ◽  
Shallow Groundwater ◽  
Ephemeral Streams ◽  
Residence Times ◽  
Acid Neutralization ◽  
Ephemeral Stream ◽  
Neutralization Capacity ◽  
Acid Neutralization Capacity ◽  
Flow Pathways

Abstract. Acid Neutralization Capacity (ANC) data for ephemeral stream and shallow groundwater for the catchments of the upper River Severn show a highly heterogeneous system of within-catchment water flow pathways and chemical weathering on scales of less than 100m. Ephemeral streams draining permeable soils seem to be supplied mainly from shallow groundwater sources. For these streams, large systematic differences in pH and alkalinity occur due to the variability of the groundwater sources and variability in water residence times. However, the variability cannot be gauged on the basis of broad based physical information collected in the field as geology, catchment gradients and forest structure are very similar. In contrast, ephemeral streams draining impermeable soils are of more uniform chemistry as surface runoff is mainly supplied from the soil zone. Groundwater ANC varies considerably over space and time. In general, the groundwaters have higher ANCs than the ephemeral streams. This is due to increased chemical weathering from the inorganic materials in the lower soils and groundwater areas and possibly longer residence times. However, during the winter months the groundwater ANCs tend to be at their lowest due to additional event driven acidic soil water contributions and intermediate groundwater residence times. The results indicate the inappropriateness of a blanket approach to classifying stream vulnerability to acidification simply on the basis of soil sensitivity. However, the results may well indicate good news for the environmental management of acidic and acid sensitive systems. For example, they clearly indicate a large potential supply of weathering components within the groundwater zone to reduce or mitigate the acidifying effects of land use change and acidic deposition without the environmental needs for Aiming. Furthermore, the high variability of ephemeral stream runoff means that certain areas of catchments where there are specific problems associated with acidification can be identified for focused remediation work for the situation where liming is required. The case for focused field campaigns and caution against over reliance on blanket modelling approaches is suggested. The results negate the conventional generalizations within hydrology of how water moves through catchments to generate streamflow events (from Hortonian overland flow to catchment contributing areas).

scholarly journals In vitro Antacid Screening of the Aqueous and Ethanolic Leaf Extracts of Ixora Coccinea (Linn). and Mimosa Pudica (Linn.)

2018 ◽  
Vol 34 (5) ◽  
pp. 2246-2252
Author(s):  
Sharmaine Jesselyn Cua ◽  
Marcelina Lirazan ◽  
Michael Russelle Alvarez
Keyword(s):  
Aqueous Extract ◽  
Buffering Capacity ◽  
Alkaloid Content ◽  
Aqueous Extracts ◽  
Mimosa Pudica ◽  
Acid Neutralization ◽  
Neutralization Capacity ◽  
Acid Neutralization Capacity ◽  
Ixora Coccinea

Ixora coccinea L. (santan) and Mimosa pudica L. (makahiya) ethanolic and aqueous extracts were screened for their in vitro antacid potentials using the preliminary antacid test, determination of acid neutralization capacity, acid neutralizing effect, duration of consistent neutralization, and buffering capacity. Phytochemical screening and quantification of alkaloids were also done and the alkaloid content was correlated to the in vitro antacid potentials of the extracts. Among the extracts, the M. pudica aqueous extract gave the best preliminary antacid test result (1.0066±0.0083 pH) and acid neutralization capacity (0.0711±0.0038 mmol H+). Its aqueous extract showed comparable acid neutralizing effect (3.507% acid neutralized) on gastric juice with that of its ethanol extract (3.509% acid neutralized). On the other hand, the I. coccinea aqueous extract had the highest acid buffering capacity (0.0701±0.0020 mmol H+/pH). Both aqueous extracts gave the longest duration of neutralization with 9±1.732 minutes. All the extracts were tested positive for flavonoids, indoles, tannins, anthraquinones, anthrones, and alkaloids, with the I. coccinea aqueous extract having the highest alkaloid content (18.0282±1.2607% w alkaloid/w extract). This study provides the first reported proof of the antacid activities of I. coccinea and M. pudica. Further tests, including mouse model assays, are suggested to determine the efficacy of the extracts in vivo.

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