Stereospecific polymerization of butyl vinyl ether at room temperature in presence of the sulfuric acid-aluminum sulfate complex

1964 ◽  
Vol 13 (10) ◽  
pp. 1749-1753
Author(s):  
M. F. Shostakovskii ◽  
A. M. Khomutov ◽  
A. P. Alimov
Keyword(s):  
Sulfuric Acid ◽  
Vinyl Ether ◽  
Room Temperature ◽  
Aluminum Sulfate ◽  
Sulfate Complex ◽  
Stereospecific Polymerization

An efficient and chemoselective Cbz-protection of amines using silica–sulfuric acid at room temperature

2007 ◽  
Vol 48 (46) ◽  
pp. 8170-8173 ◽  
Author(s):  
Manoj B. Gawande ◽  
Vivek Polshettiwar ◽  
Rajender S. Varma ◽  
Radha V. Jayaram
Keyword(s):  
Sulfuric Acid ◽  
Room Temperature ◽  
Silica Sulfuric Acid

Zinc carbonate recovery from brass melting slag

2021 ◽  
Vol 98 ◽  
pp. 14-18
Author(s):  
Thao Nguyen Thi ◽  
◽  
Nam Pham Ky ◽  
Ngoc Tran Vu Diem
Keyword(s):  
Sulfuric Acid ◽  
High Purity ◽  
Room Temperature ◽  
Ph Value ◽  
Zinc Carbonate ◽  
Leaching Solution ◽  
Optimized Conditions ◽  
Melting Slag

Brass melting slag (20.38 wt.% Zn) was leached in sulfuric acid with concentration of (50 + 80) g/l H2SO4, leaching temperature of (30 + 60) °C for (30 + 120) min. The optimized conditions for 94.16% Zn extraction from brass melting slag were found as 70 g/l H2SO4, room temperature and 90 min. The leaching solution was purified by removal of Fe through Fe(OH)3 precipitation when adding ZnO to adjust pH value of 5. The solution was continuously cemented by Zn metal at 60 °C for 60 min to obtain Cu metal with high purity of 99 wt.% Cu. The purified solution with 37.64 g/l Zn was modified by Na2C03 to have pH value of about 6 and precipitation of ZnC03 (94.14 %).

The Influence of Heat and Two Stages Precipitation in the Process of Natural Polymer Purification from the Byproduct of Bioethanol Process Base on Empty Palm Fruit Bunch

2015 ◽  
Vol 1123 ◽  
pp. 177-181
Author(s):  
Achmad Hanafi ◽  
Harry Budiman ◽  
Fauzan Aulia
Keyword(s):  
Sulfuric Acid ◽  
Sodium Hydroxide ◽  
Room Temperature ◽  
Black Liquor ◽  
Ash Content ◽  
Natural Polymer ◽  
Palm Fruit ◽  
Second Stage ◽  
Direct Precipitation ◽  
Two Stages

The biopolymer material, lignin, was recovered from the black liquor by acidification of the black liquor using sulfuric acid. Several purification techniques were carried out to produce the high purity of lignin such as gradual precipitation of lignin from black liquor (first stage: precipitation at pH 7, second stage: precipitation at pH 2) and the diluting of crude lignin by sodium hydroxide then followed by re-precipitation at different temperature. Subsequently, the impurities of lignin product resulted from each purification techniques was determined as ash content that analyzed using temperature program furnace; and the content of lignin was investigated using spectrophotometer UV-Vis. The result showed that the content of lignin of material produced from gradual precipitation was approximately 77.6%. It was higher than the content of lignin about 3.4% of material produced from direct precipitation to pH 2. In addition, the elevating of temperature from 40 to 60°C was no considerably affect to the content of lignin in precipitate produced from re-precipitation of crude lignin solution in sodium hydroxide. Nonetheless, the content of lignin of precipitate improved 15% when the temperature of re-precipitation of crude lignin solution in sodium hydroxide was raised from room temperature to 40-60°C.

Wet Chemical Etching of Zn-containing oxides and HfO2 for the fabrication of Transparent TFTs

2009 ◽  
Vol 1201 ◽  
Author(s):  
Jae-Kwan Kim ◽  
Jun Young Kim ◽  
Seung-Cheol Han ◽  
Joon Seop Kwak ◽  
Ji-Myon Lee
Keyword(s):  
Sulfuric Acid ◽  
Surface Morphology ◽  
Chemical Etching ◽  
Etch Rate ◽  
Room Temperature ◽  
Wet Chemical ◽  
Wet Chemical Etching

AbstractThe etch rate and surface morphology of Zn-containing oxide and HfO2 films after wet chemical etching were investigated. ZnO could be easily etched using each acid tested in this study, specifically sulfuric, formic, oxalic, and HF acids. The etch rate of IGZO was strongly dependent on the etchant used, and the highest measured etch rate (500 nm/min) was achieved using buffered oxide etchant at room temperature. The etch rate of IGZO was drastically increased when sulfuric acid at concentration greater than 1.5 molar was used. Furthermore, etching of HfO2 films by BF acid proceeded through lateral widening and merging of the initial irregular pits.

Reduction of Lower Concentration NO with Ammonia at Room Temperature over Pitch Based Active Carbon Fibers Calcined and Further Activated with Sulfuric Acid.

1996 ◽  
Vol 39 (2) ◽  
pp. 151-157 ◽  
Author(s):  
Isao MOCHIDA ◽  
Yuji KAWABUCHI ◽  
Motohiro HIRONAKA ◽  
Shizuo KAWANO ◽  
Yuji MATSUMURA ◽  
...  
Keyword(s):  
Sulfuric Acid ◽  
Carbon Fibers ◽  
Active Carbon ◽  
Room Temperature

scholarly journals Initial Investigation into the Leaching of Manganese from Nodules at Room Temperature with the Use of Sulfuric Acid and the Addition of Foundry Slag—Part I

Minerals ◽  
2018 ◽  
Vol 8 (12) ◽  
pp. 565 ◽  
Author(s):  
Norman Toro ◽  
Nelson Herrera ◽  
Jonathan Castillo ◽  
Cynthia Torres ◽  
Rossana Sepúlveda
Keyword(s):  
Particle Size ◽  
Sulfuric Acid ◽  
Acid Concentration ◽  
Room Temperature ◽  
Sulfuric Acid Concentration ◽  
Extraction Rate ◽  
Molar Ratio ◽  
Independent Variables ◽  
Initial Investigation ◽  
Optimization Methodology

In this study, the surface optimization methodology was used to assess the effect of three independent variables—time, particle size and sulfuric acid concentration—on Mn extraction from marine nodules during leaching with H2SO4 in the presence of foundry slag. The effect of the MnO2/Fe ratio and particle size (MnO2) was also investigated. The maximum Mn extraction rate was obtained when a MnO2 to Fe molar ratio of 0.5, 1 M of H2SO4, −320 + 400 Tyler mesh (−47 + 38 μm) nodule particle size and a leaching time of 30 min were used.

scholarly journals Synthesis and Characterization of Chemically Cross-Linked CMC/Acrylamide Hydrogels

2020 ◽  
Vol 32 (5) ◽  
pp. 1109-1115
Author(s):  
Shivakumara Lachakkal Rudrappa ◽  
Sudhir Ramaswamy Iliger ◽  
Demappa Thippaiah
Keyword(s):  
Room Temperature ◽  
Aluminum Sulfate ◽  
Ammonium Persulfate ◽  
Sem Analysis ◽  
Cross Linking ◽  
Swelling Behaviour ◽  
Buffer Solutions ◽  
Aluminium Sulfate ◽  
Chemical Cross Linking

Carboxymethyl cellulose/poly(acrylamide) (CMC/Amm) hydrogels were synthesized by the chemical cross-linking method. Ammonium persulfate used as an initiator, while aluminium sulfate used as a cross-linking agent. The structure and morphology of the hydrogels were characterized by FTIR and scanning electron microscopy (SEM) analysis. The swelling behaviour of the hydrogels can be studied by using acids (CH3COOH, HCl and HClO4) and also in the pH of the buffer solutions at different temperature (room temperature, 30 and 37 ºC) was studied. Swelling of hydrogels increased with an increase in the concentration of aluminum sulfate up to 20 %, above 20 % it has found to be decreased. The effect of four series of cationic different concentrated salt solutions on the swelling had found to be the following order K+ > Na+ > Ca2+ > Mg2+.

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