Organic Precipitation Research Articles

Micro scale chromatography of human plasma proteins for nano LC-ESI-MS/MS

Organic precipitation of proteins with acetonitrile demonstrated complete protein recovery and improved chromatography of human plasma proteins. The separation of 25 μL of human plasma into 22 fractions on a QA SAX resin facilitated more effective protein discovery despite the limited sample size. Micro chromatography of plasma proteins over quaternary amine (QA) strong anion exchange (SAX) resins performed best, followed by diethylaminoethyl (DEAE), heparin (HEP), carboxymethyl cellulose (CMC), and propyl sulfate (PS) resins. Two independent statistical methods, Monte Carlo comparison with random MS/MS spectra and the rigorous X!TANDEM goodness of fit algorithm protein p-values corrected to false discovery rate q-values (q ≤ 0.01) agreed on at least 12,000 plasma proteins, each represented by at least three fully tryptic corrected peptide observations. There was qualitative agreement on 9393 protein/gene symbols between the linear quadrupole versus orbital ion trap but also quantitative agreement with a highly significant linear regression relationship between log observation frequency (F value 4,173, p-value 2.2e-16). The use of a QA resin showed nearly perfect replication of all the proteins that were also found using DEAE-, HEP-, CMC-, and PS-based chromatographic methods combined and together estimated the size of the size of the plasma proteome as ≥12,000 gene symbols.

Performance of combined organic precipitation, electrocoagulation, and electrooxidation in treating anaerobically treated palm oil mill effluents

Palm oil mill effluent (POME), wastewater generated from palm oil production, is known for its extremely high chemical oxygen demand and brownish color. Anaerobic digestion is the primary treatment method for POME in the palm oil industry; however, anaerobically treated POME has high concentrations of residual contaminants and color intensity. This study proposes an approach to treat anaerobically-treated POME in recycled water for industrial applications by integrating preliminary organic precipitation, electrocoagulation, and electrooxidation (EO). The EO process was optimized in terms of the current density, electrolysis time, electrode arrangement, and feed flow rate. At a current density of 60 mA/cm2 and an electrolysis time of 9 min, the EO process with a graphite anode and stainless-steel cathode in the monopolar electrode configuration reduced the phenolic concentration and color in the preliminary-treated POME from 8.95 mg/L and 317.19 ADMI to 0.25 mg/L and 26.10 ADMI, respectively. Additionally, the EO process exhibited a 92.26% efficiency in lowering the ammonium-nitrogen content.

High internal phase emulsions stabilized by fluorescent phycocyanin for improved stability and bioaccessibility of β-carotene.

High internal phase emulsions (HIPE) are distinguished from ordinary emulsions by higher oil-phase percentage and better storage stability. Recently, HIPE stabilized with protein-based particles has received more attention. However, organic precipitation, chemical cross-linking and thermal denaturation are often needed to stabilize emulsions with natural proteins, and there is an urgent need to reduce the pollution of organic reagents. HIPE loaded with β-carotene stabilized by phycocyanin was prepared under mild conditions. It demonstrated strong stability in terms of temperature and storage, as evidenced by its 94.17% retention rate and 81.06% bioavailability. This stability was ascribed to the efficient defense against heat and UV rays, which was probably associated with the oil-droplet environment and interfacial protection of phycocyanin. It is speculated that the possible main interaction site between phycocyaninand sorbitol exists near amino acids 110 to 120 of the B chain. The hydrogen bond and hydrophobic interaction between them make the phycocyanin fully adsorbed on the oil-water interface when sorbitol is stable, forming a strong oil-water structure, which increases the stability of the emulsion. The outstanding fluorescence characteristics provide a feasible alternative for fluorescent emulsions to distribute and trace active compounds in vitro. HIPE loaded with β-carotene might have potential as a 3D printing material for edible functional foods. © 2024 Society of Chemical Industry.

Green nano-coated carbon electrodes for detecting furosemide drug

In this study, new coated carbon electrodes were created and utilized to estimate the furosemide (FUR) drug. Ion-pair preparation for the electrode construction involved a reaction of furosemide drug with silver nanoparticles (Ag-NPs) made from pomegranate peel extract, plasticizers that use dibutyl phthalate (DBP) without the use of any organic precipitant. Several techniques (AFM, XRD, FTIR, SEM) were used to characterize the characteristics. This electrode shows excellent sensitivity to furosemide (FUR) with a linear range of 10<sup>-6</sup> -10<sup>-1</sup> M and a correlation coefficient of 0.9798. The electrode has a lifetime of 45 days, ideal temperatures of 20-45 ºC, an optimum pH range of 3-6, a slope of 61.286 mv/decade, and a detection limit of 3.62×10<sup>-8</sup> M. The AFM was measured, the total height was 2.53 nm, and the shape was spherical or semi-spherical. The average crystal size measured by XRD was 43.52, 47, and 55.03 nm with an average size of 14.25067 nm; the particles were spherical or semi-spherical in shape, as seen using the SEM. The identification of functional aggregates was conducted by measuring them using FTIR. In conclusion, this method could be an efficient tool for determining the drug in pharmaceutical formulations.

Preparation of Lanthanum by the Lithium-thermic Method

Purification of unwanted impurities from rare earth products was carried out using inorganic and organic precipitating reagents. A 1 M solution of 8-hydroxycholine was used as organic precipitants. The use of organic precipitants forms stable intracomplex compounds with metal cations. Solutions of barium chloride and ammonia solution were used as inorganic precipitants. For the precipitant, specific and highly volatile precipitant reagents were chosen when heated. Iron, aluminum, sodium and sulfate ions were extracted from the product under study, because the chemical composition of the slag contains more of them. Enriched concentrated lanthanum chloride powder was reduced with lithium to lanthanum metal. Lanthanum is obtained in the form of large crystals with a purity of 99.6% by weight.

Kinetic and thermodynamic evidences of the Diels-Alder cycloaddition and Pechmann condensation as key mechanisms of hydrochar formation during hydrothermal conversion of Lignin-Cellulose

We investigated the kinetics and thermodynamics of the Diels-Alder cycloaddition and Pechmann condensation to evaluate the significance of both mechanisms toward hydrochar formation during hydrothermal carbonization and liquefaction of biomass. We performed well-designed experiments of semi-continuous hydrothermal conversion of pure compounds representative of lignin-cellulose fractions (i.e., D-(+)-cellobiose and 1-(3,4-dimethoxyphenyl)-2-(4-hydroxy-2-methoxyphenoxy)propane-1,3-diol) and corresponding hydrochar precursors at 220–370 °C for 60 min. We developed thermodynamically-feasible multi-phase reaction pathways and specified the kinetic and thermodynamic parameters of each pathway by fitting the reversible power-law kinetic model, Arrhenius equation, and correlation between conventional definition of Gibbs free energy and the Gibbs free energy isotherm equation into experimental data of time evolution of chemical species concentration measured using GC–MS, XRD, and μGC. Reaction pathways of mixtures of pure compounds were a combination of those for individual pure compounds. We discovered that endothermic Diels-Alder cycloaddition involving dienes and dienophile was prominent in D-(+)-cellobiose conversion pathways and functioned as an intermediate reaction producing precursors for various endothermic and exothermic precipitation mechanisms. The temperature dependence of solid organics formation via this indirect route depended on the net ΔH of a set of reaction pathways after Diels-Alder cycloaddition. In contrast, we found that the Pechmann condensation involving phenols and β-ketoester/β-ketoacid was significant in the conversion pathway of 1-(3,4-dimethoxyphenyl)-2-(4-hydroxy-2-methoxyphenoxy)propane-1,3-diol and facilitated direct precipitation of organics including 4,10-dimethyl-2,7-dioxo-2,7-dihydropyrano[2,3-g]chromene-5-carbaldehyde and 4,5-dimethoxy-2,7-dioxo-6,7-dihydro-2H-benzo[g]chromene-10-carboxylic acid. The endothermic nature of Pechmann condensation preferred higher temperatures for a higher equilibrium conversion toward solid product formation. Results in this study contributed to the improved understanding of fundamentals of hydrochar formation.

Heap leaching of ion adsorption rare earth ores and REEs recovery from leachate with lixiviant regeneration

In this work, semi-industrial scale heap leaching of 200 t ion adsorption rare earth ores (IRE-ore) and rare earth elements (REEs) recovery from lixivium was first conducted. Biosynthetic citrate/(Na)3Cit, a typical microbial metabolite, was chosen as the lixiviant to conduct heap leaching. Subsequently, an organic precipitation method was proposed, which used oxalic acid to effectively recover REEs and reduce the production cost by lixiviant regeneration. The results showed that the heap leaching efficiency of REEs reached 98 % with a lixiviant concentration of 50 mmol/L and a solid-liquid ratio of 1:2. The lixiviant can be regenerated during the precipitation process, with REE yields and impurity aluminum yields of 94.5 % and 7.4 %, respectively. The residual solution can then be cyclically used as a new lixiviant after simple adjustment. High-quality rare earth concentrates with a rare earth oxide (REO) content of 96 % can be finally obtained after roasting. This work provides an eco-friendly alternative for IRE-ore extraction to solve the environmental issues caused by traditional technology. The results proved feasibility and provided a foundation for in situ (bio)leaching processes in further industrial tests and production.

Characterization of Stromatolite Organic Sedimentary Structure Based on Spectral Image Fusion.

This paper evaluates the potential application of Raman baselines in characterizing organic deposition. Taking the layered sediments (Stromatolite) formed by the growth of early life on the Earth as the research object, Raman spectroscopy is an essential means to detect deep-space extraterrestrial life. Fluorescence is the main factor that interferes with Raman spectroscopy detection, which will cause the enhancement of the Raman baseline and annihilate Raman information. The paper aims to evaluate fluorescence contained in the Raman baseline and characterize organic sedimentary structure using the Raman baseline. This study achieves spectral image fusion combined with mapping technology to obtain high spatial and spectral resolution fusion images. To clarify that the fluorescence of organic matter deposition is the main factor causing Raman baseline enhancement, 5041 Raman spectra were obtained in the scanning area of 710 μm × 710 μm, and the correlation mechanism between the gray level of the light-dark layer of the detection point and the Raman baseline was compared. The spatial distribution of carbonate minerals and organic precipitations was detected by combining mapping technology. In addition, based on the BI-IHS algorithm, the spectral image fusion of Raman fluorescence mapping and reflection micrograph, polarization micrograph, and orthogonal polarization micrograph are realized, respectively. A fusion image with high spectral resolution and high spatial resolution is obtained. The results show that the Raman baseline can be used as helpful information to characterize stromatolite organic sedimentary structure.

Pyrolysis of sawdust impregnated with xylose: Tailoring property of biochar with sugar-derived intermediates

Cellulose and hemicellulose are major components of woody biomass, pyrolysis of which would inevitably produce anhydrate sugars or sugar-like organics. These sugars might tailor property of biochar via interactions when they pass through inner and outer surface of biochar, which were investigated herein in pyrolysis of poplar sawdust impregnated with various loading of xylose, a model sugar from hemicellulose, at 600 °C. The results suggested that the addition of xylose enhanced the cracking reactions to form more gaseous products but less biochar and bio-oil. Nevertheless, the intermediates from xylose enhanced aromatization of volatiles to form more light phenolics while aided precipitation of heavy organics on surface of biochar. The accelerated carbonization, deoxygenation and dehydrogenation reactions with presence of xylose enhanced aromatization reactions, making the biochar carbon-rich with increased heating value, crystallinity and hydrophobicity. Additionally, xylose addition could substantially enhance thermal stability of the biochar, even with loading of only 5 wt%. The DRIFTS characterization showed that the degradation of xylose produced abundant carbonyls-containing species that react with organics on surface of biochar, forming large aromatics of fused ring structures.

Formation Damage Caused by Wax Deposition Results in Shale Production Decline

_ This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 210414, “First Evidence for Shale Production Decline as a Result of Formation Damage Caused by C60+ Paraffin Wax Deposition: A Permian Case Study,” by Amir Mahmoudkhani, SPE, Locus Fermentation Solutions, and Jonathan Rogers and Martin Shumway, SPE, Locus Bio-Energy Solutions, et al. The paper has not been peer reviewed. _ Analysis of production decline curves revealed that three candidate wells in West Texas depleted faster than indicated by a type decline curve, indicating a potentially abnormal permeability-reduction mechanism. A biosurfactant-based squeeze program was recommended and applied in three horizontal wells. The biosurfactant treatment offers an alternative and economical method for remediation of formation damage caused by high‑molecular‑weight paraffin wax deposition in porous media that does not require costly intervention techniques to apply. Introduction The Bone Springs horizontal oil play in the Delaware Basin spans from southeast New Mexico into West Texas. Stacked, multipay reservoirs, each with diverse rock properties, possess upside but also complexity. The initial targets in the play were conventional sandstones. Wells then tapped into carbonate lenses and, ultimately, low-permeability sandstones. As a result of horizontal drilling technology combined with hydraulic fracturing, very thin sands and other facies are now being produced. Generally, reservoir quality of this unconventional hydrocarbon system is controlled by carbonate content, where increased carbonate content typically is associated with lower productivity. Experimental Methods All crude oils exhibited precipitation of organics at ambient laboratory temperatures. Even after storing crudes at the bottomhole temperature of 140°F, a small amount of wax remained insoluble in bulk liquid. Samples of formation drill cuttings were received for various depth intervals between 8,500 and 12,000 ft. X‑ray diffraction analyses of solids revealed quartz as the major mineral phase, with clays and carbonates account for remaining phases. Combined fractions with 160-micron size were used for microcolumn oil-recovery screening tests. Carbon distributions of oils and waxes were performed by high-temperature gas chromatography (HTGC). The Du Noüy ring method was used to measure static surface tensions of biosurfactant solutions at different concentrations and was applied to calculate critical micelle concentrations at ambient temperature. Interfacial tension (IFT) measurements were performed using a drop-shaped tensiometer using the pendant-drop method. Finally, the IFTs of oil in synthetic formation water and in biosurfactant solutions prepared in city tap water were determined. Contact-angle measurements also were performed. The wax-appearance temperature (WAT) of crude and wax samples was determined by the differential scanning calorimetry method. Spontaneous imbibition experiments were performed using the Amott-cell method at reservoir temperature. Berea sandstone core plugs (25×50 mm) with a permeability of 385 md and porosity of 18.4% were used. Core plugs were saturated with homogenized crude oil samples at 140°F for 7 days.

Approach to acute psychosis in older adults.

Approach to acute psychosis in older adults.

The Synthesis of Cu–Mn–Al Mixed-Oxide Combustion Catalysts by Co-Precipitation in the Presence of Starch: A Comparison of NaOH with Organic Precipitants

Cu–Mn mixed oxides are well known as active combustion catalysts. The common method for their synthesis is based on co-precipitation, with NaOH as a precipitant, and is burdened with the possibility of introducing undesired Na contamination. This work describes the use of two organic bases, tetrabutylammonium hydroxide and choline hydroxide, as precipitating agents in a novel alkali-free route for Cu–Mn–Al catalyst synthesis. To obtain fine crystalline precursors, which are considered advantageous for the preparation of active catalysts, co-precipitation was carried out in the presence of starch gel. Reference materials prepared with NaOH in the absence of starch were also obtained. Mixed oxides were produced by calcination at 450 °C. The precursors contained MnCO3 doped with Cu and Al, and an admixture of amorphous phases. Those prepared in the presence of starch were less crystalline and retained biopolymer residues. The combustion of these residues during calcination enhanced the formation of larger amounts of the Cu1.5Mn1.5O4 spinel phase, with better crystallinity in comparison to catalysts prepared from conventionally synthesized precursors. Tests of toluene combustion demonstrated that the catalysts prepared with starch performed better than those obtained in starch-free syntheses, and that the mixed oxides obtained by the alkali-free route were more active than catalysts prepared with NaOH. Catalytic data are discussed in terms of property–performance relationships.

The physicochemical mechanism of iron removal of aluminum sulfate solution by a novel synthesis process

Titanium dioxide is widely used as a pigment in industrial processes and life, and the mechanical strength of the coating of titanium dioxide is of vital importance for its quality. The content of iron impurities in aluminum sulfate coatings directly affects their quality; therefore, the removal of iron from aluminum sulfate solutions is of paramount importance. In this study, an aluminum sulfate solution containing iron (18 mg/L) was used as a raw material to explore a composite process to reduce iron content to< 5 mg/L for coating high-quality titanium dioxide products. A novel process consisting of sodium diethyldithiocarbamate (DDTC) complexation–precipitation, flocculation by cationic polyacrylamide, and ultrafiltration have been proposed in this study. The reactant structure and thermodynamic equilibrium were determined by quantum chemical calculations to clarify the mechanism of selective iron removal using organic precipitants. The effects of DDTC dosage, reaction temperature, reaction time, stirring speed, and ultrafiltration membrane specifications on iron removal were systematically investigated. The physical and chemical properties of the precipitated particles were analyzed by zeta potential, scanning electron microscopy (SEM), and atomic force microscopy (AFM) before and after the addition of flocculants. Before adding the flocculant, the surface zeta potential of the precipitated particles was negative, and the cationic flocculant was added to neutralize the surface charge, eliminate the electrostatic repulsion, and promote the flocculation of precipitated particles for growth; this is beneficial for ultrafiltration. Furthermore, the experimental conditions were optimized to achieve the lowest iron content of 3.8 mg/L in the solution. Finally, the reaction mechanism of the organic precipitation—cationic flocculation—ultrafiltration complex was elucidated.

A study on the composition of heavy organic precipitates at various locations of a petroleum production line: wellhead, separator, and flowline

The heavy fractions from crude oil samples from different locations of a petroleum production line was investigated by gravimetric precipitation technique through the varying of n-alkane precipitant(s) type, volume, and volume ratios. The type of heavy organics (HOs) obtained at the different locations was studied using chromatographic fractionation into saturates, aromatics, resins and residual asphaltenes. Saturates and aromatics compositions were qualitatively and quantitatively determined by Gas Chromatographic-Flame Ionization Detection (GC-FID), while Ultraviolet-Visible spectroscopy was used for the resins. The results obtained show that the amounts of HOs precipitated changes with precipitants type, volume, and volume ratios and are in the order: wellhead (WH) > flowline (FL) > separator (SR). With changes in the total volume of precipitant binary mixtures, maximum precipitation is obtained at 40 mL/g of oil. Between 70–80 mL/g of oil, the amount of precipitate produced remain constant for all samples. There is no clear-cut trend in the concentration of individual and total saturate and aromatic compositions of the heavy organics along the different locations of the production system. However, the concentration of resins increases in the order: separator > flowline > wellhead.

Using Isopropanol as a Capping Agent in the Hydrothermal Liquefaction of Kraft Lignin in Near-Critical Water

In this study, Kraft lignin was depolymerised by hydrothermal liquefaction in near-critical water (290–335 °C, 250 bar) using Na2CO3 as an alkaline catalyst. Isopropanol was used as a co-solvent with the objective of investigating its capping effect and capability of reducing char formation. The resulting product, which was a mixture of an aqueous liquid, containing water-soluble organic compounds, and char, had a lower sulphur content than the Kraft lignin. Two-dimensional nuclear magnetic resonance studies of the organic precipitates of the aqueous phase and the char indicated that the major lignin bonds were broken. The high molar masses of the char and the water-soluble organics, nevertheless, indicate extensive repolymerisation of the organic constituents once they have been depolymerised from the lignin. With increasing temperature, the yield of char increased, although its molar mass decreased. The addition of isopropanol increased the yield of the water-soluble organic products and decreased the yield of the char as well as the molar masses of the products, which is indicative of a capping effect.

Brackish water algal reefs – facies analysis as a tool to identify palaeoenvironmental variations in Miocene deposits (Mainz‐Weisenau, Germany)

Brackish‐water carbonates are far less studied than their marine or limnic counterparts. However, their association with few, specialized species enables the documentation of fine‐scale changes in the depositional environment. The Cenozoic Mainz Basin (Germany) was only sporadically connected to the North Sea and the Paratethys, exposing several transitions from marine to fresh water influence. Focusing on one outcrop of the Rüssingen Formation of Mainz‐Weisenau (Aquitanian, Miocene), we present a detailed analysis of the faunal and sedimentological responses to changing salinities and water depth, including algal reef growth and facies development. The deposits include allochthonous limestones surrounding an autochthonous reef complex and several smaller reef patches. The allochthonous facies is dominated by the gastropod Hydrobia inflata, and the reef facies is mainly made up by the green alga Cladophorites sp. The algal thalli are overgrown by cryptocrystalline, organic precipitations, and laminated, chemical precipitations. Locally, quiver‐shaped structures of Trichoptera sp. protective cases occur. The depositional setting was a shallow, low energy, and brackish environment supersaturated by carbonate. We could not confirm a general trend of reducing salinities as reported for the Rüssingen Formation. Our results question previously reported episodic desiccation events, because apparent caliche horizons actually represent thin beds of increased Cladophorites growth. Set‐up, distribution of the reef facies, and reef debris indicate short‐time variations of temperature, salinity and water depth. We conclude that these variations are based on the geographic position at the edge of an algal reef barrier, separating the Mainz Basin from the Rhine Rift Valley.

Utilisation of oil-based waste for biosurfactant production

Chemical surfactants produced in large amounts globally have severe adverse effects on environment and human health due to their non-degradable and toxic nature. Eco-friendly biosurfactants with high stability, biodegradability, and low toxicity are the need of the hour. However, biosurfactants are less preferred due to high substrate cost and cumbersome extraction process. This study focused on repurposing of lipid-rich waste like coconut oil cake, rice husk and used cooking oil as a substrate for bacterial biosurfactant production. P. aeruginosa and B. subtilis were evaluated for production and P. aeruginosa was found to be an efficient biosurfactant producer. Among the substrates, coconut oil cake gave maximum yield of 19 mg/ml. The study also focussed on optimisation of biosurfactant extraction using organic solvents and precipitation methods. The yield obtained was maximum using chloroform and methanol (2:1) extraction method. The product obtained was characterised using standard methods and confirmed for its properties. It also exhibited promising antimicrobial activity against gram-positive species.

Химический состав моющего раствора воды после промывки колесных пар железнодорожного транспорта

The article discusses the impact of economic and industrial water consumption on the state of the hydrosphere and biosphere of the Earth, and also presents the water consumption in Russia, the share of the country's water resources consumed per year and the forecast of water consumption at the end of 2020. The classification of modern methods of wastewater treatment, including in railway depots, is considered. The water consumption and the proportion of circulating water at railway enterprises are analyzed in detail, as well as the most used methods of purification of the used detergent solution (DS) in the enterprise are presented. The description of the work presents the key characteristics of the DS after washing the wheelsets of railway transport, such as pH, total hardness, density and permanganate oxidizability. The data obtained were compared with the requirements (2.1.4.1074-01) and concluded that the water was unsuitable for further operation due to a significant excess of the norm for permanganate oxidizability. The effect of long-term sedimentation of the studied DS was investigated, after which DS was successfully separated into an aqueous phase, an organic phase, a black amorphous organic precipitate, and a yellow amorphous precipitate. The influence of a direct electric current, conducted through the solution at room temperature on carbon electrodes, was studied for a time of 30 minutes, one and three hours. The influence of changes in the pH of the DS medium with subsequent settling was studied. The results of chemical purification of the water under study with such coagulants as ammonium polymolybdate and bismuth(III) salts, the latter of which made it possible to precipitate phosphate ions from solution, are presented. A qualitative reaction with the use of ammonium thiocyanate proved the content of iron(III) ions in the test solution.

Change of sandstone microstructure and mineral transformation nearby UCG channel

In order to study the evolution law of surrounding rock microstructure of underground coal gasification, and to reveal the principle from the change of mineral composition and organics in rock, the sandstone nearby the gas transmission channel was used as the tested rock. In this paper, the rock was heated at 300, 400, and 500 °C, simulating the heat convective environment of the gas transmission channel. The mineral, organic functional groups, and microstructure of sandstone transformation products were detected by XRD, FTIR, and SEM. It is concluded that the kaolin in the sandstone gradually transforms into metakaolin with the increase of temperature, meanwhile the carboxyl group and the oxygenic functional group decrease. The generation of metakaolin and the precipitation of organics increase the number of fractures in samples, which is the main reason for the compressive strength and elastic modulus for the sandstone decreases with increasing temperature for temperatures greater than 500 °C. The microscopic manifestation is the appearance of a large number of flocs on the surface. Macroscopically, the exterior appears as a grayish shell. The flow resistance and the adsorption property are weakened, and the permeability is enhanced.

Highly active and poison-tolerant nickel catalysts for tar reforming synthesized through controlled hydrothermal synthesis

Nickel catalysts suffer from the loss of tar reforming activity due to poisoning by syngas impurities. The strategy of increasing activity of catalysts through selection of suitable organic precipitants for hydrothermal synthesis was investigated. Catalysts were synthesized from nickel and aluminum nitrates using urea, N,N’-dimethylformamide, N-methylurea, 1,1-dimethylurea and N,N’-dimethylurea as precipitants and screened for naphthalene reforming. The catalyst prepared with urea maintained the highest reforming activity for 10 h in the presence of 50 ppmv H2S (80 % naphthalene conversion, 800 °C). This was attributed to lower chemisorption of sulfur on Ni sites, due to the larger percentage of Ni0 and Ni aluminates which are less susceptible towards sulfidation than NiO. The precipitant also influenced the water gas shift activity which was higher in case of N,N’-dimethylformamide and urea probably due to Ni aluminate formation. Thus, a type of precipitant plays an essential role in tailoring of catalysts for syngas upgrading.