Petroleum sulphonates

Dispersants To keep insoluble combustion and oxidation products in suspension and dispersed Salts of phenolic derivatives polymers containing barium, sulphur and phosphorus calcium or barium soaps of petroleum sulphonic acids... 

Most of the inhibitors in use are organic nitrogen compounds and these have been classified by Bregman as (a) aliphatic fatty acid derivatives, b) imidazolines, (c) quaternaries, (d) rosin derivatives (complex amine mixtures based on abietic acid) all of these will tend to have long-chain hydrocarbons, e.g. CigH, as part of the structure, (e) petroleum sulphonic acid salts of long-chain diamines (preferred to the diamines), (/) other salts of diamines and (g) fatty amides of aliphatic diamines. Actual compounds in use in classes (a) to d) include oleic and naphthenic acid salts of n-tallowpropylenediamine diamines RNH(CH2) NH2 in which R is a carbon chain of 8-22 atoms and x = 2-10 and reaction products of diamines with acids from the partial oxidation of liquid hydrocarbons. Attention has also been drawn to polyethoxylated compounds in which the water solubility can be controlled by the amount of ethylene oxide added to the molecule. 

One of the main problems associated with beneficiation of the Kolwezi siliceous ore is the production of malachite and pseudomalachte slimes that have a relatively low flotation rate. Most of the copper losses occurring in the plant are in the -15 pm fraction. Experimental testwork conducted with a different palm oil emulsifier indicated that copper recovery from the fine fraction can be significantly improved with the use of petroleum sulphonate (Petrosol 845) as the emulsifier [21] for palm oil. Significant improvement in copper recovery was realized in the fine fractions with the use of palm oil emulsified with Petrosol 845. 

Floatability of bastnaesite found in barite-fluorite ores is extremely poor using either fatty acid flotation or sodium oleate. Research work conducted on an ore from Central Asia showed that the floatability of bastnaesite improved significantly after barite preflotation [5]. The flotation of bastnaesite from a carbonatite ore improved with the use of oleic acid modified with phosphate ester. The flotation of bastnaesite from deposits ofpegmatitic origin can be successfully accomplished with several types of collectors, including tall oil modified with secondary amine, and tall oil modified with petroleum sulphonate-encompassing group. 

For flotation of barite, sodium silicate was used as a depressant and barium chlorite as a barite activator. Barite collector SR82 was composed of petroleum sulphonate, sodium alkyl sulphate and succinamate mixture. The collector was selective towards both fluorite and bastnaesite. Over 96% of the barite was recovered in a relatively high-grade concentrate. 

Most recently, development testwork was performed on a large perovskite deposit (Powderhom) located in the USA. An effective beneficiation process was developed, where a concentrate assaying >50% Ti02 was achieved in the pilot plant confirmation tests [7]. During this development testwork, a number of different collectors were examined at different pH values. Figure 25.5 shows the effect of the different collectors on perovsikte flotation. The most effective collector was phosphoric acid ester modified with either fatty alcohol sulphate or petroleum sulphonate. 

Based on data shown in Figure 25.9, ilmenite recovery was a function of both pH and collector modifications. The optimum flotation pH was between 3 and 5. Phosphoric acid esters modified with petroleum sulphonate gave the highest recovery. 

Due to their high molecular weights, these compounds are easily removed by distillation. There is a market for the dialkylbenzenes which can be sulphonated to produce synthetic petroleum sulphonates. 

The so-called petroleum sulphonates are close cousins to LAB in that they are sulphonated alkyl aromatics but the molecular weight of the alkylate is higher than that of detergent LAB and the product is somewhat less water soluble. The aromatic portion of the surfactant may also be toluene (methylbenzene) or xylene (dimethylbenzene). Principal applications are as oil emulsifiers, lubricant additives and corrosion inhibitors. 

Raw materials. Petroleum sulphonates were originally obtained as by-products of white oil or lubricant oil production. In this process, the oil was treated with sulphuric acid, sulphonating aromatic compounds which could then be separated from the non-polar oils. These were further separated into oil soluble ( mahogany ) and water soluble ( green )... 

The high molecular weight fractions from LAB manufacture can also be used as raw materials for petroleum sulphonates. The preferred feed is the dialkylbenzene which can give products of similar performance to a custom-made C20+ alkylbenzene. The alkylate still bottoms (as these materials are often called) also contain diphenyl alkanes. When sulphonated, these become highly water soluble and should be removed, either by distillation of the organic feed, or separation from the oil soluble sulphonates. 

Alkylates made specifically as feedstocks for synthetic petroleum sulphonates are typically long chain (average C chain > 16) and may use propylene oligomers which result in branched chains. Naphthalene products use the same propylene technology but tend to shorter chains (di-isopropylnaphthalene, di-nonylnaphthalene). 

Shorter chain sodium alkylbenzene/alkylxylene sulphonates (sodium salts) are used as emulsifiers for oil in water systems. Cutting fluids are often made by diluting an oil-based concentrate containing a petroleum sulphonate with water, at the point of use. The petroleum... 

Phosphate esters are widely used in metalworking and lubricants. A C12 h with 6 mol of ethylene oxide (diester) can be used as an emulsifier but also as an extreme pressure additive - it can reduce wear where there is high pressure metal to metal contact. PEs can also show corrosion inhibiting properties, as with petroleum sulphonates and the emulsifying power of PEs with low foam is used in agrochemical formulations. PEs can act as dispersants or hydrotropes in plant protection formulations, allowing the development of easy-to-handle and dilute formulations of both poorly miscible and insoluble herbicides. 

Calcium sulphate in phosphoric acid (wet process for phosphoric acid) Petroleum sulphonate surfactants/hydrocarbon liquid Conditioned in mixer, pellets formed by tumbling... 

Natural sulphonates are not, by themselves, namrally occurring but were historically obtained as by-products of white oil manufacture. In recent years, however, they have been produced as first-intent products. Normally, natural sulphonates are obtained as the neutral sodium salts. These materials have also been referred to as petroleum sulphonates or mahogany acid soaps. Reaction sequence (7.5) shows the formation of natural sulphonates ... 

Sodium petroleum sulphonates or calcium dinonylnaphthalene sulphonate can be applied as rust preventing additives and the catalytic effect of copper can be retarded by 2-mercaptobenzothiazole. Depending on operating temperature, various oxidation inhibitors may be used. Thus, 2,6-di-fert-butyl-4-methyl phenol is an effective inhibitor below 120 C while phenyl-alpha-naphthylamine is widely used in greases at low temperatures and above 120" C and phenothiazine is effective especially at temperatures above 150" C. Special compounds used as oxidation inhibitors for greases in the food industry are dilauryl thiodipropionate or citric acid. 

Figure 3.2 Plots of the salinity (5) versus the alkane carbon number (ACN). (a) Optimum formulation lines as the locus of the minimum interfacial tension, i.e. of the three-phase region centre, (b) Optimum formulation line as the locus in bidimensional S-ACN map for the same water-oil-alcohol systems containing different surfactants at constant temperature. CnOXS stands for alkylorthoxylene sulphonates, ABS for alkyl benzene sulphonate, PS for petroleum sulphonate (the number after PS indicates the average molecular weight).

Figure 3.11 Variations of optimum salinity (5) as a function of the temperature (7) for an anionic surfactant (0 wt.% Nl), a non-ionic (100 wt.% Nl) surfactant and their mixtures. The systems contain equal amounts of water and n-heptane, 3 wt.% 2-butanol and 1 wt.% surfactant mixture (Nl + Al). Nl, polyethoxylated nonylphenol with an average of 6.5 ethyleneoxide units Al, petroleum sulphonate sodium salt with an average molecular weight of 420 g/mol.

Cheap commercial anionic surfactants of the petroleum sulphonate type might contain disulphonates that are likely to partition in water, thus resulting in a similar fractionation phenomenon. However, this time the candidates to partition in water are the very hydrophilic disulphonates and thus the remaining more lipophilic species are more likely to adsorb at interface. As a consequence the interfacial or microemulsion formulation is more lipophilic [33]. Since this is just the opposite of the previously discussed case of polyethoxylated nonyl phenols, the two phenomena are able to cancel out provided that... 

The double-alkylated arenes, as dibutylnaphthalene, have some importance also as starting materials for alkylarylsulphonates. So, dibutylnaphthalene can be obtained by a reaction between naphthalene and butanol at 25-35 °C catalysed by sulphuric acid. Another raw material source for alkylarylsulphonates ( petroleum sulphonates) are the oil cuts enriched with alkylarenes. 

In the detergent industry sulphonation processes with sulphuric acid, oleum and SO3-complexes are essentially of historical significance, and are not any longer used in developed countries. In the production of white oils, however, sulphonation with concentrated sulphuric acid and oleum is still used. The sulphuric acid treatment of selected petroleum fractions lead to petroleum sulphonates the sodium or ammonium salts of which are used in tertiary oil recovery, metallurgy, froth flotation and concrete industry, while the magnesium, calcium and barium salts are used as dopes in fuels and lubricants. The sulphonation with chlorosulphonic acid continue to remain useful in batch processes, typically on a relatively small scale ... 

The thermal stability of several petroleum sulphonates and non-ionic surfactants has bem investigated in relation to heavy oil recovery by several workers . The stability of toe surfactants is reported in terms of toe time required for half of toe surfactant to decompose (i.e. half life). In order to determine toe half-lives for petroleum sulphonates at different temperatures, the activation energy... 

Semi-synthetic oils contain mineral oils of concentrations varying between io% and 50%. They therefore provide more lubrication than synthetic oils. To enable the mineral oil to blend with water and remain in a finely dispersed state requires the addition of emulsifiers (20-40%). These are often based on petroleum sulphonates, which are produced by the sulphuric-acid treatment of spindle oils to produce white oils and carboxylic acids. 

Soluble (emulsifiable) oils are composed mainly of mineral oils (concentration 60-80%), which also require emulsifiers (20-40%) to enable the oil to blend. Supplied neat, they have an oily appearance but, on dilution with water, they take on a characteristic milky colour and may be referred to by the workforce as suds . If petroleum sulphonates are used alone as emulsifiers, then the pH of the soluble oil tends to lie... 

Alkylnaphthalene sulphonates (typically R = C4H9-) Petroleum sulphonates, e.g. 

Surfactant systems capable of producing ultra-low interfacial tensions are currently attracting attention because of their potential value in increasing the recovery of oil from underground reservoirs [11-15]. The systems used contain co-surfactant, salt, and complex ill-defined mixtures of surfactants known as petroleum sulphonates. There is evidence to suggest that the interfaces present during the recovery processes are not simple liquid-liquid phase boundaries with surfactant monolayers [11,12,16,17] and it has been suggested that the ultra-low tensions are caused by the presence of a surfactant-rich third phase at the interface. 

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