An Overview of Surfactant Applications in Drilling Fluids for the Petroleum Industry

Surfactants are increasingly being used in an ever-expanding variety of applications for drilling fluids. In oil-based drilling fluids, the most well-known applications of surfactants are as emulsifiers and wetting agents. In water-based drilling fluids, there is a continually-growing variety of applications that include:

• oil-in-water emulsification in base fluid formulations;

• shale-swelling inhibitors to prevent wellbore instabilities;

• detergency to prevent cuttings sticking to drill bit (adhesion of clay to metal parts);

• prevention of differential sticking;

• dispersants to inhibit flocculation of clay particles;

• foaming additives, to generate high gas/water ratio foam used as drilling fluids for low-pressure reservoirs and hard-rock drilling;

• defoaming additives to eliminate undesirable foam in water-based fluids;

• surfactant-polymer complexes for enhanced properties in fluids for low-pressure reservoirs.

This review describes historical and modern applications of surfactant technology in drilling fluids, and the impact of those molecules on drilling operations. Proper selection and application of surfactants in drilling fluids have a significant economic impact, in terms of reducing the amount of lost time and potential trouble, and have a direct consequence on overall drilling performance and results.     

Sources of Errors Associated with the Determination of PAH and PCB Analytes in Water Samples

Abstract

This work describes the problems occurring in routine determination of polyaromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) in water. On the basis of experiments carried out, sources of analyte losses in a particular step of the analytical procedure were identified and assessed. Primary attention has been paid to evaluation of the?following:

• degree of adsorption of analytes from the group of PCBs and PAHs on the walls of glass vessels used during sample pretreatment and storage

• influence of excess of solvent evaporation from extracts on analyte recoveries

• influence of material of extraction column (glass, polyethylene) on analyte recovery during the solid extraction process.

     

IUPAC Commission on Inorganic Chemistry Nomenclature; Newsletter 1990

Inorganic Chemistry Nomenclature

IUPAC Commission on Inorganic Chemistry Nomenclature; Newsletter 1990     

Electrodeposition of Copper in Presence of Carbohydrates

The rates of electrodeposition of copper plates were determined by measuring cathodic limiting current in the absence and in the presence of carbohydrates (glucose, fructose, mannose, sucrose, lactose, and maltose). It is found that the rate of electrodeposition decreases in the presence of organic additives by an amount ranging from 1.89% to 35.85%, and depending on the types of additives and its concentrations. Our investigation of adsorption isotherm indicates that the inhibition fits both the Langmuir adsorption isotherm and Flory-Huggins adsorption isotherm; we found that the rate of electrodeposition decreases by increasing height and increasing CuSO₄ concentrations. Thermodynamic parameters are given and show that electrodeposition process is diffusion controlled. The rate of deposition and its equations are represented:

• Sh = 0.099Re^0.715 Sc^0.33 for glucose with average deviation: ±0.158%

• Sh = 0.097Re^0.715 Sc^0.33 for fructose with average deviation: ±0.058%

• Sh = 0.099Re^0.715 Sc^0.33 for mannose with average deviation: ±0.108%

• Sh = 0.098Re^0.713 Sc^0.33 for sucrose with average deviation: ±0.003%

• Sh = 0.099Re^0.714 Sc^0.33 for lactose with average deviation: ±0.018%

• Sh = 0.099Re^0.713 Sc^0.33 for maltose with average deviation: ±0.097%.

     

A review on environmental applications of chitosan biopolymeric hydrogel based composites

Abstract

Chitosan (CS) is being used for fabrication of low cost, biocompatible materials that have applicability in fields such as agriculture, biotechnology and environment. In Environmental research, one of the applications of CS based hydrogel composites are in form of biosorbents for eviction of toxic dyes, heavy metals and nutrients from effluent streams. The adsorption potential could be attributed to the reactive functional groups existing on the surface of CS. CS based materials can also be employed for oil/water separation, as a fertilizer carrier, in Microbial fuel cells as Electrolyte membrane and as Electrochemical/Biosensors for detecting and analyzing few environmental pollutants such as pesticides. The earlier review papers on the subject matter have concentrated mainly on dye and heavy metal removal without giving details of its utility in the field of electrochemistry and agriculture. Though the biopolymer holds numerous applications, it has not been discussed extensively. Thus, an attempt has been made to elucidate the current and potential applications of CS hydrogels and composites based on the efficacy it has shown in areas of removal of organic and inorganic contaminants such as dyes, heavy metals and nutrients, in agriculture, oil and water separation, Microbial Fuel cells and Electrochemical/Biosensors.

• HIGHLIGHTS

• Chitosan based hydrogel composites could be extensively used in the field of Environment Technology.

• The composites act as effective biosorbents for dye, heavy metal and nutrient removal because of the functional groups present on Chitosan’s surface.

• These can also be effectively used for oil/water separation and also as a fertilizer/pesticide carrier for their slow release.

• Chitosan based electrolytes can become a promising ecofriendly substitute for synthetic polymers in fuel cells.

• These biopolymers have also been researched upon as electrochemical/biosensors in recent years for detecting environmental pollutants.

     

Dediazoniation of Arenediazonium Ions in Homogeneous Solution. Part XII. Solvent effects in competitive heterolytic and homolytic dediazoniations

In heterolytic dediazoniations arenediazonium salts form aryl cations. The reaction rates are relatively slow; they depend only to a small extent on the solvent. It is shown that the solvents in which the heterolytic dediazoniation mechanism is predominant have a low nucleophilicity, whereas in solvents of high nucleophilicity homolysis of arenediazonium salts, i.e. the formation of aryl radicals and related intermediates, is favoured. Under comparable conditions, homolytic rates are faster than the corresponding rates of heterolysis. Homolysis is strongly enhanced by addition of nucleophiles which form relatively stable radicals by electron transfer. The ability of additives to catalyze homolysis of arenediazonium salts can be explained using the concept of a nucleofugic

1 In the original proposal [32] we used the word nucleofugal. In keeping with a forthcoming proposal on nomenclature in physical organic chemistry by Commission III.2 (Physical Organic Chemistry) of IUPAC we now use the word nucleofugic.

homolytic leaving group.     

Sample Stability of Trace Priority Substances in Wastewater

A series of sample stability tests has been undertaken to support a large UK-based survey of trace substances in wastewater. This program aims to quantify the input of priority chemicals to the aquatic environment via sewage effluent. The stability tests have demonstrated that, in most cases, the proposed approach of chilling samples meets the target that sample concentrations should not change by more than 25%, provided samples are analyzed or otherwise stabilized within 3–5 d. Substances tested fall into three main classes:

• Instability in effluents greater than the project-based threshold of 25% over 3–5 d can be ruled out provided samples are chilled for: DEHP (DEHA), glyphosate, AMPA, bentazone, mecoprop, ofloxacin, erythromycin, and ibuprofen;

• Some indication of possible instability up to 25% provided chilled storage periods do not extend beyond 3–5 d for: mercury (note requires acid dichromate preservation on site or as soon as possible), tributyltin, bisphenol A, reactive aluminum (in effluents, note requires filtration on sampling), oxytetracycline, and propranolol; and

• Clear stability problems are demonstrated for salicylic acid (effluents and influents), with indications of important instability (>25%) for bisphenol (effluents) AMPA and glyphosate (influents).

     

Imidazo- und Diazino-Anellierungen an das [1]Benzothieno[2,3—d]pyrimidin-System

Derivatives of the following six ring systems were synthesized:

1. 3,10-Dihydro-[1]benzothieno[2,3-d]imidazo[1,5-a]-pyrimidine (I)
2. 6H-[1]Benzothieno[2,3-d]pyrazino[1,2-a]pyrimidine (II)
3. 1,5-Dihydro-[1]benzothieno[2,3-d]imidazo[1,2-a]-pyrimidine (III)
4. 6H-[1]Benzothieno[2,3-d]pyrimido[1,2-a]pyrimidine (IV)
5. 1,5-Dihydro-imidazo[1,2-a]thieno[2,3-d]pyrimidine (V)
6. 4H-Pyrimido[1,2-a]thieno[2,3-d]pyrimidine (VI)

The first four types are new heterocyclic systems. 2-Aminomethyl-5,6,7,8-tetrahydro-[1]benzothieno[2,3-d]pyrimidin-4(3H)-one (5), which was used as intermediate for typesI andII, was synthesized by various methods. TypesIII andIV were prepared from 2-methylthio-5,6,7,8-tetrahydro-[1]-benzothieno[2,3-d]pyrimidin-4(3H)-one via the corresponding 2-benzylamino derivatives, followed by ring closure.     

Condensed pyridopyrimidines. 1. Synthesis of new derivatives of pyrano[3′,4′∶5,6]pyrido[2,3-d]pyrimidines

New derivatives of pyrano[3,45,6]pyrido[2,3-d]pyrimidines were synthesized from ethyl 2-amino-7,7-dimethyl-7,8-dihydro-5H-pyrano[4,3-b]pyridine-3-carboxylate.A. L. Mndzhoyan Institute of Fine Organic Chemistry, National Academy of Sciences of the Republic of Armenia, Erevan. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1239–1241, September, 1999.     

Erweiterung und Revision der Nomenklatur der Spiroverbindungen

Die Übersetzung basiert auf der „Extension and Revision of the Nomenclature for Spiro Compounds“ der Commission on Nomenclature of Organic Chemistry (III.1) der Organic Chemistry Division der International Union of Pure and Applied Chemistry, veröffentlicht in Pure Appl. Chem. 1999 , 71, 531–558. Sie ist auch im Internet unter der Adresse http://www.chem.qmul.ac.uk/iupac/spiro/ zugänglich. Das Original wurde von G. P. Moss (Queen Mary University, London) für die Veröffentlichung vorbereitet.     

Synthesis of macrocycles having tröger base skeletons “[2.2]cyclic tröger base”

[2.2]Cyclic Tröger base2 was synthesized by the condensation of 1,2-bis (4-aminopheyl) ethane with paraformaldehyde under acidic condition in 43.8% yield. [2.2]Cyclic Tröger base2 was separated into meso form and racemate by fractional crystallization or using HPLC. Resolution of the racemate into its optical antipodes by passing the racemate through an activated D-(+)-lactose column was partially succeeded.Presented at the 15th Symposium on Structural Organic Chemistry, Kyoto, October, 1982.The trivial name [2.2]cyclic Tröger base is used because of the cumbersome nomenclature.10,12,25,32-Tetraazanonacyclo[19.7.7.1^4,8.1^14,18.1^25,32.0^7,12.0^7,12.0^10,15.-0^24,34.0^27,31] octatriaconta-1(29),4,6,8(36),14,16,18(37),21,23,27,-30,34-dodecaene.     

Derivatives of condensed thienopyrimidines. 11. Synthesis of 2,4-dithioxopyrano(thiopyrano)-[4′,3′∶4,5]thieno[2,3-d]pyrimidines

Methods for the synthesis of 2,4-dithioxo-6,6-dimethyl-5,6-dihydro-8H-pyrano(thiopyrano)[4,34,5]thieno[2,3-d]pyrimidines have been developed.For Communication 10 see [1].A. L. Mndzhoyan Institute of Technical Organic Chemistry, National Academy of Sciences of the Republic of Armenia, Erevan 375014. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 803–804, June, 1998.     

Reactions of the Carbonyl Group in Fluorinated Ketones

The chemistry of polyfluorinated ketones has recently received a great deal of attention.

1 A. Ya. Yakoubovich, Usp. Chim. 25, 3 (1956).

2 H. P. Braendlin and E. T. McBee in: Advances in Fluorine Chemistry. Butterworths, London 1963, Vol. 3, p. 1.

3 The review by Braendlin and McBee [2] does not deal only with perfluorinated ketones; moreover, though published in 1963, it is already outdated. The papers discussed in [1,2] will not be reviewed in the present article.

. The carbonyl and imino groups of the fluorinated ketones and their imines react in many different ways. In particular, the electron-attracting perfluoroalkyl groups intensify the electrophilic properties and weaken the nucleophilic properties of the carbonyl group. The perfluoroalkyl group also hinders the heterolytic removal of the hydroxyl group from adducts by reducing the stability of the carbonium ion . The increased electrophilicity of the carbonyl group and the increased stability of the addition products leads not only to a change in reactivity in the characteristic ketone reactions, but also to numerous new reactions which are not observed with non-fluorinated ketones. Thus it is possible to synthesize a wide variety of fluoroorganic compounds from perfluorinated ketones.

4 We have been concerned mainly with hexafluoroacetone, since in addition to being the most readily available and simplest perfluorinated ketone, this is also a typical representative of this class of compounds.

.     

Steric Rate-Retardation in the Chromium Trioxide Oxidation of 4,6-Dimethyl-benzocyclobutenol

The rate of oxidation of 4, 6-dimethyl-benzocyclobutenol

1 This nomenclature is preferred in the literature [1] [2] to the more systematic name (7-hydroxy-3, 5-dimethyl-bicyclo [4.2.0] octa-1,3,5-triene).

( 1 ) with chromium trioxide has been measured. After correction for the influence of the two methyl substituents the rate of oxidation of 1 is lower than that of 1-tetralol ( 9 ) and 1-indanol ( 10 ) by factors of 3 and 5 respectively. The lower oxidation rate of 1 as compared to 9 and 10 is interpreted in terms of a steric rate retardation arising from angle strain in the developing carbonyl function of 4, 6-dimethylbenzocyclobutenone ( 4 ).     

A Novel Organophosphorus Compound as a Coupling Reagent for Peptide Synthesis

3-(Diethoxyphosphoryloxy)-1,2,3-benzotriazin-4 (3H)-one 1 is a new organophosphorus compound which can be used as an efficient coupling reagent for peptide synthesis by either solution or solid phase coupling.

Standard abbreviations for amino acids and protecting groups follow the IUPAC-IUB Joint Commission on Biochemistry Nomenclature: J. Biol. Chem. 1971, 247, 977.     

A green synthesis of 3,4-dihydropyrimidin-2-ones and 1,5-benzodiazepines catalyzed by Sn(HPO4)2.H2O nanodisks under solvent-free condition at room temperature

Abstract

Heterogeneous Tin (IV) hydrogen phosphate nanodisks [Sn(HPO4)2.H2O] efficiently catalyzed the one-pot three component condensation of aromatic aldehydes, β-ketoesters and urea to produce 3,4–dihydropyrimidin-2-ones under solvent-free conditions at room temperature. Also, the catalyst is equally applicable for the preparation of 1,5–benzodiazepines under the same reaction conditions. The optimum load of the catalyst required is 10 mole% and reusable. Hence, the process is green.

Novel Asymmetric Synthesis of (S)-Esmolol Using Hydrolytic Kinetic Resolution

An efficient asymmetric synthesis of (S)-methyl 3-[4-[2-hydroxy-3-(isopropyl amino) propoxy] phenyl] propanoate is described. The key intermediate (S)-methyl 3-[4-(oxiran-2-ylmethoxy) phenyl] propanoate was obtained by hydrolytic kinetic resolution method using Jacobsen catalyst.

Synthesis of triazoles and tetrazoles condensed with spiro(benzo[h]quinazoline-5,1′-cyclohexane)

Condensation of 3-R-4-oxo-2-thioxo-1,2,3,4,5,6-hexahydrospiro(benzo[h]quinazoline-5,1-cyclohexanes) with 2-ethanolamine, 3-propanolamine, and hydrazine hydrate gives the corresponding 2-ethanolamino, 2-propanolamino, and 2-hydrazino derivatives. Triazoles and tetrazoles, a- or b-condensed with benzo[h]quinazolines were obtained from 2-hydrazinobenzo[h]quinazolines depending on the presence of a substituent at position 3.A. L. Mndzhoyan Institute of Fine Organic Chemistry, Armenian Republic Academy of Sciences, Yerevan 375014. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 396–400, March, 2000.     

Erweiterung und Revision des von‐Baeyer‐Systems zur Benennung polycyclischer Verbindungen (einschließlich bicyclischer Verbindungen)

Die Übersetzung basiert auf der „Extension and Revision of the von Baeyer System for Naming Polycyclic Compounds (Including Bicyclic Compounds)“ der Commission on Nomenclature of Organic Chemistry (III.1) der Organic Chemistry Division der International Union of Pure and Applied Chemistry, veröffentlicht in Pure Appl. Chem. 1999 , 71, 513–529. Sie ist auch im Internet unter der Adresse http://www.chem.qmul.ac.uk/iupac/vonBaeyer/ zugänglich. Das Original wurde von G. P. Moss (Queen Mary University, London) für die Veröffentlichung vorbereitet.