Stable carbonium ions. LXIII. Diprotonated aliphatic alkoxy alcohols and their cleavage in strong acid solution. Stable secondary alkoxycarbonium ions

1968 ◽  
Vol 90 (16) ◽  
pp. 4323-4327 ◽  
Author(s):  
George A. Olah ◽  
Jean. Sommer
1967 ◽  
Vol 89 (20) ◽  
pp. 5259-5265 ◽  
Author(s):  
George A. Olah ◽  
Melvin B. Comisarow ◽  
Eli. Namanworth ◽  
Brian G. Ramsey

1970 ◽  
Vol 48 (22) ◽  
pp. 3545-3548 ◽  
Author(s):  
John Warkentin ◽  
Kenneth E. Hine

Dehydration of the four isomeric butanols by strong acid at about 160° gives a C4-fraction containing isobutane as well as the isomeric butenes. Isobutane probably arises by hydride transfer, from one or more donors including the substrate alcohol and hydrocarbons formed from it in the medium, to one or more carbonium ions including the t-butyl cation. Materials which react with 2,4-dinitrophenylhydrazine reagent to form 2,4-dinitrophenylhydrazones can be swept out of the hot acid solution with a stream of nitrogen.


2019 ◽  
Vol 19 (1) ◽  
pp. 33-42
Author(s):  
Mirna Aparecida Neves ◽  
Simone Pereira Taguchi ◽  
Douglas Rosa da Silva ◽  
Fabrício Thiengo Vieira

Dimension stones are worldwide used as building and finishing material, reason why the environmental problems inherent to this productive sector became relevant in various countries. One of these problems is the production of large amounts of wastes during the sawing of rocky blocks and polishing of plates. The waste generated by cutting marble with diamond wire consists of fine particles of calcium and magnesium carbonate dispersed in water. This mud has basic character, and it is destined to drying beds or open pit deposits. In parallel, many production processes generate hazardous acidic effluents, which disposal is a serious and global problem. The pH of these solutions must be neutralized or, at least, raised to levels that are considered safe by environmental regulations. In this work, a strong acid solution was treated with varying amounts of marble waste coming from the dimension stone industry. The treatment generated secondary solid and liquid phases that were analyzed to determine the feasibility of their disposal in landfills. The waste raised the pH of the acid solution from near 1.0 to values between 5.0 and 6.0, which are acceptable levels for non-dangerous effluents. Besides that, loss of up to 50% in mass occurred, diminishing the amount of the primary solid waste. By the other hand, the levels of total dissolved solids (TDS), Cu, chlorides and nitrates on the liquid phase of the effluent remained higher than that allowed by environmental legislation for discharge into water bodies. Nevertheless, their characteristics correspond to non-hazardous and non-inert wastes, which, after dried, can be discarded in ordinary waste landfills.


2003 ◽  
Vol 68 (10) ◽  
pp. 765-769
Author(s):  
Sofija Rancic ◽  
Rangel Igov ◽  
Todor Pecev

A new reaction is suggested and a new kinetic method is elaborated for the As(HI) traces determination in solution, on the basis of their catalyzing effect on komplexon III (EDTA) oxidation by KMnO4 in a strong acid solution (H2SO4). Using a spectrophotometric technique, a sensitivity of 72 ng/cm3 As(IIl) was achieved. The relative error of method varies from 5.5 to 13.9 % for As(HT) concentration range from 83 to 140 ng/cm-1. Appropriate kinetic equations are formulated and the influence of some other ions, including the As(V), upon the reaction rate is tested.


Author(s):  
Kou-Ming Lin ◽  
Ching-Tu Chang ◽  
Ming-Shin Wu ◽  
Wen-Chen Lee ◽  
Jen-Chieh Chung ◽  
...  

Metal scrap is a major waste generated from the decommissioning of nuclear facilities. Through a decontamination process, most of the metal scraps can be cleaned to meet the clearance levels, which can then be reused or released according to the regulatory procedure. Usually, chemical processes will be used in the cleaning step. Phosphoric acid and fluoroboric acid are the typical chemicals used for decontamination. Although the decontaminant could be reused multiple times after regeneration, its decontamination efficiency would decrease after 3 to 5 cycles. In addition, the radioactive nuclides such as Cs-137 are not easily removed during the regeneration process; it tends to accumulate slowly in the decontaminant. According to the ALARA principle, decontaminant must be replaced if its radioactive activity exceeds the regulatory levels. As a result, a significant amount of spent strong acid solution would be generated. The conventional way of treatment is to neutralize the acid solution with an alkaline solution. However, such method will produce a large amount of sludge that requires further stabilization, which offsets the advantages of metal decontamination by use of the decontaminant. A high-efficiency solidification method has been developed and used to treat the spent phosphoric acid and fluoroboric acid solution in Institute of Nuclear Energy Research (INER). The self-polymerization nature of highly concentrated phosphoric acid is adopted to immobilize the radioactive nuclides. The volume of solidified form is almost equal to that of the treated acid solution. The waste form demonstrates its quality by compression test and leaching test. This cementation process is an excellent method to minimize the secondary waste, which is generated from chemical decontamination for treating metal waste.


2019 ◽  
Vol 280 ◽  
pp. 05019
Author(s):  
Hesti Wijayanti ◽  
Iryanti Fatyasari Nata ◽  
Rinny Jelita

Rice husk is considered as agricultural waste that causes environmental problem during its handling. In this study, rice husk was treated with acid (citric acid and nitric acid) solutions prior used as raw material for producing biofuel and chemicals via pyrolysis. The pyrolysis behaviors of rice husk treated with water and acid solutions have been investigated through thermogravimetric analysis from room temperature to 600 oC at the heating rate of 10oC/min under 50 ml/min nitrogen flow. Demineralization treatment using strong acid (nitric acid) solution showed more impacts to the rice husk in thermogravimetric analysis, i.e. lower ash content, less minerals content and thermal stability increased. One step model kinetic resulted the lowest activation energy (12.8709 kJ/mol) occured at the 5% nitric acid solution treatment. Excellent agreement between the experimental data and model predictions was found with 8.63% of the relative error. In other words, demineralization using 5% nitric acid solution would improve rice husk performance during its pyrolysis reaction for producing biofuel.


1991 ◽  
Vol 255 ◽  
Author(s):  
Konstantinos Beltsios ◽  
S. H. Carr

AbstractConductive composite fibers are prepared by dry-jet wet-spinning of a strong-acid solution of rod-like polymers and phthalocyanine(Pc) compounds. A model yielding a hierarchical structure for a pure rigid-rod fiber is described first. The inclusion of NiPc in the spinning dope leads upon coagulation to isolated NiPc domains that are predicted to correspond to body centered cells (exhibiting various degrees of disorder). The observed dependence of fiber conductivity of composition is explained in terms of tunneling and percolation processes.


1979 ◽  
Vol 101 (7) ◽  
pp. 1896-1898 ◽  
Author(s):  
F. M. Menger ◽  
J. M. Jerkunica
Keyword(s):  

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