This review covers the main agents used for in situ and ex situ chemical oxidation of organic contaminants particularly oil products, in soil and water environments. Among them there are hydrogen peroxide, permanganate salts, ozone and sodium persulfate. The fields of application, as well as benefits and disadvantages of the mentioned agents use were described.
Oxidation of tert-butyl alcohol (TBA) to methacrolein (МA) over Fe-Te-Mo-Ox catalyst (Cat), promoted by Ca(NO3)2 has been investigated. Promoter concentration, which was optimal by the МA yield, has been established (Ca/Mo = 0.05). Using catalyst of such type the MA yield was 87.1 % (calculated for supplied TBA) at the temperature of 663 K, process time of 2.5 s and TBA concentration of 7.0 % with concentration of water vapour in the air of 20 %. Under mentioned conditions TBA conversion was 100 %, isobutylene conversion – 95.5 %, selectivity by MA was 87.6 % and by CO2 – 2.4 %.
The process of high-sulphuric brown coal oxidative desulphurization has been studied. The effect of grain size and oxidant linear rate on the process parameters has been determined. During the process the main part of pyritic sulphur is converted into hydrogen sulphide resulting in forming the gases with H2S high content which may be utilized or processed by the known methods
The antioxidant properties and stability during the storage of hexane solutions of 5 individual essential oils from clove bud (Caryophyllus aromaticus L.), cardamom (Elettaria cardamomum L.), laurel (Laurus nobilis L.), nutmeg (Myristica fragrans Houtt.), and mace (Myristica fragrans Houtt) were studied by the method of capillary gas-liquid chromatography. We assessed the antioxidant properties by the efficiency of autooxidation inhibition of aliphatic aldehyde (trans-2-hexenal) into the corresponding carbon acid.
The tar oxidation process has been studied at 523 K, air flow rate of 2.0; 2.5 and 5.0 h-1 and process time of 6, 9 and 12 h in the presence of 2.5; 5.0 and 7.5 mas % (to calculate for the raw material)of petroleum resin with fluorine atoms. The tar is the residue of black oil vacuum distillation obtained from the oils of Western-Ukrainian fields. The effect of process conditions on the characteristics of obtained bitumen has been determined. The structural-group composition of blown bitumen has been examined.
Methyl methacrylates synthesis via oxidative conversion of isobutyl alcohol has been investigated in accordance with different schemes. The possibility of its use as an alternative raw material instead of isobutylene and tert-butyl alcohol has been established. Using the scheme isobutyl alcohol methacrylonitrile methyl methacrylate the product with ultimate yield of 64.8 % has been obtained. Taking into consideration the recirculation of unreacted methacrolein the yield is 81.9 %. This scheme may be recommended for industrial application.
Influence of individual compounds with innercomplex properties in the liquid phase cyclohexane oxidation process has been considered.
The oxidation process of the paraffin gas condensate residual has been studied to obtain road bitumen. The investigation results concerning the residual joint oxidation with extract of oil selective treatment and low-paraffin tars are presented. It has been determined that bitumen obtained from the residual of paraffin gas condensate treatment does not meet the requirements setting for road bitumen. It is recommended to use the residuals for the production of building or covering bitumen.
Article contains results of oxidation of different classes of hydrocarbons (alicyclic, alkylaromatic) in the presence of catalytic systems containing salt of variable valence metal and organic additive of different nature (perfluorooxasulphonates, crown-ethers, polyglycols). It was found that the influence of investigated catalytic systems depends on the nature of the hydrocarbon and the nature of the additive. The main areas of influence of organic additives on the rate and selectivity of oxidation of hydrocarbons were considered and the most probable ones were proved.
Reaction of low temperature oxidations of ethylene glycol (EG) by molecular oxygen in the presence of salts of bivalent copper and alkali both in water and in waterless solutions was investigated. It was found that at low (close to room) temperatures and in waterless solutions the basic product of EG oxidation is formic acid. Rise in the temperature from 290–315 K to 350–360 K or reaction flow in water-containing solutions leads to sharp change of reaction direction. EG in these conditions is oxidized with primary formation of glycolic acids salts.