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Article
Publication date: 1 February 2012

Y.L. Lam, C.W. Kan and C.W.M. Yuen

A systematical review of catalyst was provided in the paper involving the definition, the sort, effect mechanism and the influence factors which followed that the…

Abstract

A systematical review of catalyst was provided in the paper involving the definition, the sort, effect mechanism and the influence factors which followed that the application of catalyst in the textile industry in terms of dyeing, finishing and effluents treatment. Catalyst is defined as a substance that could change the rate of chemical reaction, while it is not consumed in the overall reaction. The changing of the reaction rate by means of catalyst is known as catalysis. Catalyst could assist in either acceleration or deceleration of the reaction rate. In textile processing, especially in textile wet processing such as dyeing and finishing, for example, easy care and durable press finishes, antimicrobial finishes, ultraviolet protection finishes, flame retardant finishes and water repellent finishes, various types of catalysts will be involved for achieving desired effect. However, there is a less discussion and review on the relationship on the effect of catalyst on the final properties of the textile materials. Therefore, the aim of this paper is to provide a comprehensive review of the application of catalyst on the textile wet processing and nano-catalyst was also evaluated in the extending to the opportunities and development of textile industry.

Details

Research Journal of Textile and Apparel, vol. 16 no. 1
Type: Research Article
ISSN: 1560-6074

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Article
Publication date: 1 January 1976

A. Rantell and A. Holtzman

Mixed SnCl2/PdCl2 catalyst solutions are often used to catalyse the board surface prior to metallising by electroless deposition. An accelerator is also required in the…

Abstract

Mixed SnCl2/PdCl2 catalyst solutions are often used to catalyse the board surface prior to metallising by electroless deposition. An accelerator is also required in the catalysing sequence in order to boost the catalytic activity of the surface. Skip plating is a prime source of unreliability and can often be traced to low catalytic activity. Processing variables directly affecting catalytic activity are discussed. These include surface roughness, type of accelerator employed and its operating conditions, and the efficiency of rinsing as well as the composition of the catalyst solution. The mechanism of catalysis is also discussed, involving theories of the colloidal and complex nature of the catalyst solution.

Details

Circuit World, vol. 2 no. 2
Type: Research Article
ISSN: 0305-6120

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Article
Publication date: 9 January 2009

Z. Gao, X‐M. Wang, H. Wan and Zhi‐Ming Liu

The purpose of this paper is to investigate the effects of various catalyst contents, resin solid contents, catalyst species and wood extract on urea‐formaldehyde (UF…

Abstract

Purpose

The purpose of this paper is to investigate the effects of various catalyst contents, resin solid contents, catalyst species and wood extract on urea‐formaldehyde (UF) curing by differential scanning calorimetry (DSC) technique. The finding obtained would benefit the manufacturers of UF‐bonded composite panels.

Design/methodology/approach

The UF curing rate under each condition in terms of DSC peak temperature was measured by high‐pressure DSC at a heating rate of 15°C/min; the correlations of peak temperature with catalyst content, resin solid content, catalyst species and wood extract, respectively, were regressed via a model equation, which described the curing characteristics of the UF bonding system.

Findings

A model equation, Tp=A · EXP(−B · CC per cent)+D, was proposed to characterise the DSC peak temperatures or the rate of UF curing with regressing coefficients greater than 0.97 (commonly greater than 0.99). The constants A and B in the model equation were found to correspond to kinetic characteristics of UF resin curing reaction. The constant D in the model equation is believed to be associated with the utmost peak temperature, which implies that the DSC peak temperature will finally reach a maximum with catalyst content increasing. It was also found that the wood extracts having higher pH value and base buffer capacity had stronger catalyses on UF curing.

Research limitations/implications

The catalysts commonly used in medium density fibreboard plants or particleboard plants are those having the utmost peak temperature of about 90‐95°C; the catalyses of wood extracts were much weaker than that of catalyst NH4Cl.

Practical implications

The model equation could be used to predict the peak temperature or the curing rate of UF resin, and to quantify the effects of wood extracts on UF curing.

Originality/value

The study developed a model equation that can well characterise the UF curing, and quantified the effects of wood extracts on UF curing.

Details

Pigment & Resin Technology, vol. 38 no. 1
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 14 June 2011

F. Ozil, V. Tschamber, F. Haas and G. Trouvé

Because domestic heating appliances have the advantage of reducing emissions of greenhouse gas, their use is greatly increased and is largely recommended by European…

Abstract

Purpose

Because domestic heating appliances have the advantage of reducing emissions of greenhouse gas, their use is greatly increased and is largely recommended by European governments. However, some recent studies revealed that residential wood stoves and inserts are the source of many chemicals in the form of gases (CO2, CO, SO2, NOx), volatile organic compounds (alkane, alkenes, benzene, etc. …) and tars (mainly constituting poly‐aromatic hydrocarbons). The most important of them in terms of the emission factor and impact on environment and human health are carbon monoxide and fine particles. The aim of this study is to test the activity of a Pd‐based catalyst on the reduction of gas and particles during wood combustion in a domestic fireplace.

Design/methodology/approach

A catalytic system, placed at the exit of the fireplace, was developed to reduce pollutants. Pollutant characterization of a domestic fireplace from FONDIS SA, according to two paces of functioning (nominal and low‐charge), was performed with and without the presence of the catalyst. Fine and ultrafine particle distributions were characterized using an Electrical Low Pressure Impactor.

Findings

The presence of a catalyst drastically decreases the emission factors of CO. Though performing efficiently with respect to the total suspended particles emission factor, it does not significantly affect the emission factors of aerosols. Nevertheless, in the presence of the catalyst, air supply conditions slightly modify size distributions of PM0.1 to PM10.

Practical implications

A purification assembly, having catalysts for gases and combustion fumes from solid fuel heating apparatus, was patented and fireplaces are now commercially available from FONDIS SA.

Originality/value

This work was an adaptation of the catalytic system present in the automotive Diesel exhaust engines. It was not necessary to consult previous laboratory experiments in order to perform its activity because it was directly tested at the duct fireplace.

Details

Management of Environmental Quality: An International Journal, vol. 22 no. 4
Type: Research Article
ISSN: 1477-7835

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Article
Publication date: 1 March 1981

D.A. Luke

Until recently the majority of catalysts used in through‐hole plating of printed circuits have been based on processes containing tin and palladium. These have been…

Abstract

Until recently the majority of catalysts used in through‐hole plating of printed circuits have been based on processes containing tin and palladium. These have been adequate although, with the ever increasing demands on quality of subsequently assembled printed circuits, they have shortcomings which are functions of the basic formulae and mechanisms of operation. The new non‐precious metal catalyst based on copper operates over a much wider range of conditions and, unlike palladium catalysts, promotes complete coverage of epoxy glass laminates. The operation of both catalyst systems is discussed in depth and compared, significant emphasis being placed on the mechanism of surface activation.

Details

Circuit World, vol. 7 no. 4
Type: Research Article
ISSN: 0305-6120

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Article
Publication date: 4 July 2016

Lihong Gao, Jiang Chen, Jun Zheng and Haiyan Zhang

The purpose of the study reported in this paper is to synthesis curcumin, which was reported to possess broad pharmacological effects and excellent dyeing properties, via…

Abstract

Purpose

The purpose of the study reported in this paper is to synthesis curcumin, which was reported to possess broad pharmacological effects and excellent dyeing properties, via Claisen-Schmidt condensation reaction catalysed by an efficient and green solid base catalyst, KF/Al2O3.

Design/methodology/approach

A series of catalysts with different KF loadings and varying calcination temperatures had been prepared, characterised by Brunauer–Emmett–Taller surface area, temperature-programmed desorption with CO2 using infrared spectroscopy, X-ray powder diffraction and X-ray photoelectron spectroscopy, and tested in the Claisen–Schmidt condensation reaction. The effects of different reaction parameters such as temperature, the amount of catalyst, reactant ratio and time on the synthesis of curcumin were examined. The possibility of recycling the catalyst was also investigated in detail. Moreover, the reaction mechanism and the role of KF/Al2O3 in the synthetic process were discussed.

Findings

The study provides an efficient and green solid base catalyst, KF/Al2O3, and 64.3 per cent yield of curcumin was obtained under the optimum reaction conditions. Experimental results indicate that the third reused catalyst could retain part of the catalytic activity, and the regenerated one could be reused with reasonable catalytic activity. Besides, K3AlF6 was proposed as the active site of the catalyst for the reaction by the analysis of the characterization results of KF/Al2O3.

Originality/value

KF/Al2O3 was found to be an efficient catalyst for catalytic synthesis of curcumin and could be easily recycled several times. This information may be useful for further research and practical applications of curcumin.

Details

Pigment & Resin Technology, vol. 45 no. 4
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 4 January 2013

R.D. Kulkarni, M.E. Chaudhari and S. Mishra

The purpose of this paper is to provide a critical and in‐depth review of the present status and recent developments in synthetic methodologies, reaction engineering…

Abstract

Purpose

The purpose of this paper is to provide a critical and in‐depth review of the present status and recent developments in synthetic methodologies, reaction engineering, process design and quality control aspects associated with the manufacture of mono and multifunctional acrylate monomers.

Design/methodology/approach

This paper reviews commercially important UV cure mono and multifunctional acrylate monomers. It covers their synthesis, catalyst, and appropriate solvents for azeotropic removal of byproducts. The detail discussion on catalysis, basis of design of reactors and commercial plant and the process engineering associated with the manufacture has been supported through citation of synthesis of various acrylate monomers. The methodologies adopted for determination of physical, chemical and compositional characterisation of acrylate monomers have been presented. In addition, the guidelines regarding the bulk storage and commercial handling of acrylates have been reviewed.

Findings

The reaction engineering of esterification reaction between acrylic acid and polyol has been worked out to provide the basis for selection of reactors. The reaction has been modeled as a series – parallel complex reaction for providing explanation for generation of various byproducts/adducts and multiple esters.

Practical implications

The detailed discussion on formation, characterisation and treatment of Michael adducts and purification of acrylate monomers will be relevant for new researchers for further development. A review of guidelines on selection of homogenous and heterogeneous catalysts for synthesis of acrylate monomers has been presented.

Originality/value

Since the related literature on acrylate monomers is scarce, scattered and proprietary, the consolidated coverage in one paper will be useful.

Details

Pigment & Resin Technology, vol. 42 no. 1
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 1 October 2005

Mary‐Ellen Boyle and Edward Ottensmeyer

Business leaders, in increasing numbers, are looking to the creative power of the arts in their efforts to manage strategic change, to enhance innovation, or to strengthen

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Abstract

Purpose

Business leaders, in increasing numbers, are looking to the creative power of the arts in their efforts to manage strategic change, to enhance innovation, or to strengthen corporate cultures. In this case study, we focus attention on what is widely regarded as one of the world's most extensive corporate arts‐based learning initiatives, the Catalyst program at Unilever.

Design/methodology/approach

In a wide‐ranging interview with James Hill, now a group vice‐president and Catalyst's leading executive sponsor, this paper explores the origins, operations, and outcomes of this innovative program.

Findings

Finds that Catalyst came about as a result of savvy leadership and a corporate willingness to take risks in developing an “enterprise culture;” it now flourishes in three divisions due to ownership at multiple levels of the organization as well as its ability to stimulate new product development, attract and retain creative people, and boost the company's marketing efforts; and it persists because its starting points are always actual business problems, the solutions to which improve financial performance and shareholder returns.

Originality/value

To management scholars, this case provides an additional data point in the ongoing study of strategy implementation and organizational change. To corporate executives seeking fresh ideas, the Unilever/Catalyst story offers a novel and intuitively appealing approach to the vexing challenges of leading strategic change, told from the perspective of an experienced executive.

Details

Journal of Business Strategy, vol. 26 no. 5
Type: Research Article
ISSN: 0275-6668

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Article
Publication date: 1 December 2001

Hakan Kaleli

Two 10W30 mineral‐base phosphorus containing (commercial) and phosphorus‐free (P‐Free) crankcase oils were tested in the engine dynamometer for the poisoning effects on a…

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1033

Abstract

Two 10W30 mineral‐base phosphorus containing (commercial) and phosphorus‐free (P‐Free) crankcase oils were tested in the engine dynamometer for the poisoning effects on a catalytic converter and emission‐engine’s performance. The emission results of the two oils were compared with and without a catalytic converter, including the light‐off temperature of the catalyst. Surface characterisation was used to determine accumulated catalyst poisoning from the oil additives. The performance analysis shows that the catalytic converter lowers the torque and power for the commercial and P‐Free oils, whereas the specific fuel consumption increases for both oils in the presence of the catalytic converter. In both cases of the presence and the absence of catalytic converter the torque, power and specific fuel consumption remain the same for phosphorus containing and P‐Free oils. The presence of the catalytic converter shows lower HC and CO and higher CO2 emissions for both P‐Free and commercial oils. Surface characterisation using x‐ray microanalysis techniques of Scanning Electron Microscopy and indicated residual amounts of poisons, predominantly P, Ca, S and Zn deposited on the catalyst.

Details

Industrial Lubrication and Tribology, vol. 53 no. 6
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 16 October 2019

Yusuf Yivlik, Nilgun Kizilcan and Ahmet Akar

Cyclohexanone–formaldehyde resin (CFR) was in situ modified with isocyanuric acid (ICA) in the presence of hydrochloric acid or p-toluenesulfonic acid by condensation…

Abstract

Purpose

Cyclohexanone–formaldehyde resin (CFR) was in situ modified with isocyanuric acid (ICA) in the presence of hydrochloric acid or p-toluenesulfonic acid by condensation polymerization. The purpose of this study is to produce isocyanuric acid-modified ketonic resins that have higher melting and decomposition temperature, and to use the produced resin in the production of fire-retardant polyurethane.

Design/methodology/approach

Two methods were used for in situ preparation of ICA-modified CFR in the presence of an acid catalyst. Method I: cyclohexanone, paraformaldehyde and ICA were mixed, and then an acid catalyst was added to form the modified CFR. Method II: ICA and formalin were mixed to produce N, N, N-trihydroxymethyl isocyanurate, and then water was removed under vacuum. The produced N, N, N-trihydroxymethyl isocyanurate solution was mixed with cyclohexanone and paraformaldehyde, then an acid catalyst was slowly added to this mixture to obtain ICA-modified CFR.

Findings

CFR was prepared in the presence of an acid catalyst. The product, CFR, has a dark red colour. The resulting resins have similar physical properties with the resin prepared in the presence of a basic catalyst. The solubility of ICA-modified CFR is much different than CFR in organic solvents.

Research limitations/implications

This study focuses on obtaining an ICA-modified ketonic resin. Cyanuric acid has the form of an enolic structure under a basic condition; therefore, it cannot give a product with formaldehyde under basic conditions. The modification experiments were carried out in acidic conditions.

Practical implications

This study provides technical information for in situ modification of ketonic resin in the presence of acid catalysts. The resins may also promote the adhesive strength of the coating and provide corrosion inhibition on metal surfaces for a coating. The modified resins may also be used in the field of fire-retardant polyurethane applications.

Social implications

These resins may be used for the preparation of non-toxic fire-retardant polyurethane foam. Polyurethane containing ICA-modified resin may exhibit better fire-retardant performance because of the incorporation of ICA molecule into the polyurethane structure.

Originality/value

ICA-modified CFRs have been synthesized in the presence of an acid catalyst, and the ICA-modified resin was used to produce fire-retardant polyurethane.

Details

Pigment & Resin Technology, vol. 49 no. 2
Type: Research Article
ISSN: 0369-9420

Keywords

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