ANTAGONISM BY SPECIES OF ALTERNARIA AND THE ISOLATION OF A CRYSTALLINE SUBSTANCE FROM THE FILTRATE OF CULTURES OF A. RADICINA

1953 ◽  
Vol 31 (4) ◽  
pp. 423-425 ◽  
Author(s):  
Wm. Newton
Keyword(s):  
Activated Carbon ◽  
Sodium Hydroxide ◽  
Sulphuric Acid ◽  
Ethyl Alcohol ◽  
Acid Water ◽  
Crystalline Substance ◽  
Pink Color ◽  
Phytophthora Erythroseptica ◽  
Water Suspensions ◽  
Alternaric Acid

Culture filtrates of five species of Alternaria were antagonistic to Phytophthora erythroseptica. Those of A. radicina exerted the greatest effect and they were followed in order of effectiveness by A. dianthicola, A. solani, A. brassicicola, and A. tenuis. The antagonistic principle in the filtrate of A. radicina was readily removed by activated carbon. By extracting this carbon with acetone, substantial yields were obtained of colorless, needlelike crystals, quite insoluble in water, but readily soluble in acetone, ethyl alcohol, ether, benzene, concentrated sulphuric acid, and 10% sodium hydroxide. The m.p. of the crystals, 204 °C. to 208 °C, and the deep pink color in solutions of sodium hydroxide distinguish the substance from alternaric acid. Water suspensions of the crystals were much less antagonistic to P. erythroseptica than the original filtrate and had little or no effect upon several species of bacteria.

Modification of activated carbon using sodium acetate and its regeneration using sodium hydroxide for the adsorption of copper from aqueous solution

Carbon ◽  
2007 ◽  
Vol 45 (5) ◽  
pp. 1081-1084 ◽  
Author(s):  
Dan Mugisidi ◽  
Aria Ranaldo ◽  
Johny W. Soedarsono ◽  
Muhammad Hikam
Keyword(s):  
Aqueous Solution ◽  
Activated Carbon ◽  
Sodium Hydroxide ◽  
Sodium Acetate

Potentiostatic studies of the corrosion of grey cast iron in sulphuric acid and sodium hydroxide solutions

1987 ◽  
Vol 27 (3) ◽  
pp. 221-228 ◽  
Author(s):  
Lammia M. Al-Shama ◽  
Jalal Mohammed Saleh ◽  
Naema A. Hikmat
Keyword(s):  
Cast Iron ◽  
Sodium Hydroxide ◽  
Sulphuric Acid ◽  
Grey Cast Iron ◽  
Grey Cast

scholarly journals TRANSESTERIFICATION OF VEGETABLE OILS’ TRIGLYCERIDES BY THE HEAD FRACTION OF ETHYL ALCOHOL

2021 ◽  
pp. 72-79
Author(s):  
Yurii Melnyk ◽  
Stepan Melnyk ◽  
Halyna Mahorivska
Keyword(s):  
Cation Exchange ◽  
Sodium Hydroxide ◽  
Ethyl Alcohol ◽  
Vegetable Oils ◽  
Exchange Resin ◽  
Sodium Hydroxide Solution ◽  
Cation Exchange Resin ◽  
Term Treatment ◽  
Esterification Reaction ◽  
Hydroxide Solution

The regularities of sunflower, rapeseed and flaxseed oils’ triglycerides transesterification by the head fraction of ethyl alcohol in the presence of various catalysts have been investigated. The cation exchange resin KU-2-8 in H+-form and cation exchange resin KU-2-8 containing an immobilized Cu2+-ions (untreated and treated by 0,1 M sodium hydroxide solution for 90 min and for 7 days) were used as catalyst. It was shown that the all investigated catalysts except the untreated cation exchange resin KU-2-8 containing an immobilized Cu2+-ions allow to achieve of triglycerides conversion over 90 % under the reaction conditions. It was found that the catalyst KU-2-8 containing an immobilized Cu2+-ions treated by 0.1 M sodium hydroxide solution for 90 min shows the highest activity. Also it was found that this catalyst allows to achieve triglyceride conversion all of studied vegetable oils over 99.5% in 180 min of reaction. Simultaneously it was found that the highest rate of transesterification reaction in its presence is observed. The influence of these catalysts on the esterification reaction of free fatty acids, present in vegetable oils, by ethyl alcohol, present in the head fraction, was studied. It was established that the influence of the investigated catalysts on the esterification reaction is different. It was shown that cation exchange resin KU-2-8 containing an immobilized Cu2+-ions treated by 0.1 M sodium hydroxide solution for 90 min catalyzes the esterification reaction of free fatty acids of all investigated oils. Their conversion is from 21.6 % (in sunflower oil) up to 74.1 % (in rapeseed oil). At the same time, it was found that long-term treatment of cation exchange resin KU-2-8 containing an immobilized Cu2+-ions by sodium hydroxide solution leads to a sharp decrease or loss of catalyst activity in the esterification reaction of free fatty acids by ethyl alcohol. It was shown that the use of this catalyst for the transesterification of rapeseed and sunflower oils’ triglycerides even increases the acid number of the reaction mixture, namely to the partial hydrolysis of triglycerides. The obtained results show that the short-term treatment the cation exchange resin KU-2-8 containing an immobilized Cu2+-ions by 0.1 M alkali solution is one of the ways that allow to increase its catalytic activity in the transesterification process of vegetable oils by head fraction of ethyl alcohol. It is assumed that such treatment affects the catalytic activity of Cu2+-ions due to changes in the electron density on the catalyst cation caused the coordination of part of the OH–-anions. The long-term treatment of the cation exchange resin containing an immobilized Cu2+-ions by alkali solution causes a maximum saturation of the cation coordination sphere. This obviously creates steric problem of a reagents access to the catalyst and reduces the catalytic activity cation exchange resin.

Modification of Starch Using Itaconic Anhydride and its Characterizations

2021 ◽  
Vol 874 ◽  
pp. 149-154
Author(s):  
Dita Rengganis ◽  
Rachmawati Rachmawati
Keyword(s):  
Chemical Modification ◽  
Sodium Hydroxide ◽  
Sulphuric Acid ◽  
Thermal Behaviour ◽  
Modified Starch ◽  
Sem Micrographs ◽  
Itaconic Anhydride

In this study, the chemical modification of starch was conducted using itaconic anhydride as an esterifying agent. The results showed that sulphuric acid is more effective as a catalyst for esterification of starch compared to sodium hydroxide. The presence of attached itaconic anhyride in the starch affected the thermal behaviour and crystallinity of the resulting products as shown by the TGA, DSC, and the XRD data. In addition, the SEM micrographs also indicated that the modified starch exhibited a unique morphology in the form of block with different sizes ranging from 1 to 20 μm in length.

Production of activated carbon from a new precursor molasses by activation with sulphuric acid

2005 ◽  
Vol 118 (1-3) ◽  
pp. 259-263 ◽  
Author(s):  
K. Legrouri ◽  
E. Khouya ◽  
M. Ezzine ◽  
H. Hannache ◽  
R. Denoyel ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Sulphuric Acid
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