Alkaline Reagents Research Articles

Hydroxide-ion induced complete mineralization of poly(tetrafluoroethylene-co-hexafluoropropylene) copolymer (FEP) in subcritical water

Decomposition of poly(tetrafluoroethylene-co-hexafluoropropylene) copolymer (FEP) in supercritical and subcritical water was investigated with the aim of waste treatment. The efficiency of such decomposition was examined by using either oxidizing agents (O2, H2O2) or an alkaline reagent (KOH). When O2 was chosen, the highest F– and CO2 yields, 75 % and 64 %, respectively, were obtained from a reaction of FEP in supercritical water at 384 °C for 24 h. Under these conditions, traces of CHF3 were detected in the gas phase, the amount of which decreased with increasing the reaction time·H2O2 gave slightly higher reactivity than O2. In contrast, reactions with KOH induced efficient fluorine mineralization. When FEP reacted in 3.0 M KOH solution at 360 °C for 18 h, the F– yield reached 98 %. Hence, complete fluorine mineralization was achieved, where very little CO2 (∼0% yield) and no CHF3 were generated in the gas phase. Furthermore,19F NMR spectroscopy and combustion-ion chromatography revealed that the reaction solutions did not contain any organofluorine compounds during the reactions. FEP decomposed, releasing F– into the reaction solution, resulting in the formation of amorphous carbon in the residue.

Moderate strategy for efficient recovery of rare earth elements from scintillation crystal waste

The lutetium has been known to be used in medical imaging materials, but its scarcity in the Earth’s crust makes it expensive. In this work, we present a process for efficient lutetium recovery from the lutetium-yttrium oxyorthosilicate crystals (LYSO) waste. The process involves preliminary mechanical activation, followed by rare earth extraction via acid leaching. The key factors for activation and leaching were studied and optimized. The mechanism of mechanical activation promoting rare earth leaching was revealed by employing the characterizations of morphology and crystal structure of LYSO. It was found that the mechanical activation process could destroy the crystal structure of LYSO waste, forming numerous amorphous phases and grain boundaries, which facilitated the breaking of existing bonds and mass transfer of acid. It was also discovered that the formation of silica gel during leaching impedes the leaching of rare earth, and low concentrations of hydrochloric acid, combined with stirring during acid leaching, could reduce the impact of silica gel. Ultimately, following a mechanical activation pretreatment at 300 rpm for 90 min, 98.7 % of lutetium could be leached after 60 min of acid leaching in 3 mol/L hydrochloric acid. This process addresses the problems associated with high energy consumption and excessive usage of acidic and alkaline reagents in conventional recycling techniques. Compared to conventional methods, the mechanical activation-acid leaching method has a minimum economic benefit improvement of 20.8 % in the process of recovery from LYSO waste. It offers an alternative and more energy-efficient and economical recycling route for waste scintillation crystals.

Synergistic enhancement of the photocatalytic activity of g-C3N4 via in-situ surface alkalization and CQDs loading strategies

The CQDs/alkaline carbon nitride heterojunction photocatalysts were synthesized employing dicyandiamide as the nitrogen material, Citric acid was used as the carbon source, while KCl and NH4Cl were as alkaline reagents. The study investigated the influence of CQDs on the adsorption performance, photocatalytic activity, and band structure of alkalized carbon nitride. The dark adsorption results revealed that CNK/CQDs1: 12 exhibited outstanding adsorption performance, capable of degrading adsorbed pollutants in a relatively short period. The photocatalytic degradation study demonstrates that CNK/CQDs1:12 exhibits significantly higher degradation efficiencies compared to the pristine CN and alkalinized CNK samples, with degradation efficiencies of 94.4 % for Methylene Blue (MB) and 71.68 % for tetracycline hydrochloride (TC-HCl) within 60 min. This is due to the synergistic effects of alkalization of the g-C3N4 surface and CQDs loading, which modified the heterojunction interfacial charge transfer efficiency, suppressing the recombination of photoelectron-hole pair, extending the life span of transient photogenerated carriers, thereby improving photocatalytic activity. Free radical trapping experiment indicated that h+ and ·O2− are the primary active species during the photocatalytic degradation process of CNK/CQDs1:12.

TREATMENT OF COPPER FLUE DUST FROM FLASH FURNACE WASTE HEAT BOILER FOR IMPURITIES CONTROL

During the pyrometallurgical processing of copper sulphide raw materials, part of the charge leaves the furnace space together with the exhaust gases in the form of dust entrainment. Volatile components also pass into the dust-gas flow, due to which it is enriched with impurities, some of which are harmful to the technological process. The formed dust-gas flow passes through dust collection equipment, where the main part of it is captured. Most often, the captured dust is recirculated, which leads to a decrease in the productivity of the furnace unit and a gradual increase in the content of impurities in the condensed products of the smelting. To overcome these disadvantages, it is necessary to take part or all the recirculating dust out of the melting cycle and process it independently to extract the valuable metals and dispose of the harmful substances. In metallurgical practice, industrial application for the processing of recirculating dust entrainment has mainly been accomplished by hydrometallurgical methods based on treating the flue dust in aqueous solutions of acid or alkaline reagents. In the present research work, laboratory results on hydrometallurgical leaching of flue dust from a flash furnace waste heat boiler (FF-WHB) are presented. The effect of the main technological parameters affecting the degrees of recovery of the main metals in solution was studied. Based on the experimental results, the optimal conditionsfor hydrometallurgical treatment of the FF-WHB flue dust were determined. By treating the dust under optimal conditions, the main tasks of the research are achieved - removal of impurities harmful to the technological process and reduction of the amount of flue dust processed in the flash furnace.

Unlocking Enhanced Electrochemical Performance of MBene-MoB Through Controlled Aluminum Dissipation from MoAlB.

2D transition metal borides, known as MBenes, have attracted considerable attention due to their exceptional properties. This study explores the feasibility of aluminum (Al) etching from MoAlB using environmentally friendly and sustainable fluoride-free dilute acidic/alkaline solutions at room temperature, revealing its thermodynamic and kinetic viability. Furthermore, it is found that complete removal of Al can be achieved in dilute alkaline reagent under hydrothermal conditions, yielding pristine single/few-layered MBene-MoB for the first time, while acidic solutions result in ≈33% etching rates. XRD refinement, which tracks aluminum removal from 0% to 100%, reveals transient metastable phases of MoAl1-xB (x<0.5) in the initial etching stages, evolving into relatively stable pure Mo2AlB2 structures with 50% Al deficiency, serving as a precursor to MBenes. The subsequent loss of Al results in a 2D MBene-MoB structure. DFT calculations confirm excellent conductivity for MoAlB, MoAl1-xB (x=0-1), and MBene-MoB. Remarkably, MBene-MoB exhibits superior supercapacitor performance with a 4025.60mFcm-2/201.28Fg-1 capacitance. Simulations validate rapid electrolyte diffusion in layered MBene-MoB, contributing significantly to enhanced capacitance. Additionally, in the hydrogen evolution reaction (HER), MBene-MoB demonstrates superior catalytic activity compared to the precursor MoAlB and commercial MoB. Calculations suggest the potential for enhancing HER through surface modulation, considering its suboptimal hydrogen adsorption energy.

Facile preparation of oxygen vacancy-rich magnesium oxide for advanced removal of phosphate from aqueous solutions

In this study, oxygen vacancy-rich magnesium oxides (SH-MgO and SC-MgO) were successfully prepared by the combination of chemical precipitation with high-temperature calcination. Effects of alkaline reagents (NaOH and Na2CO3) on surface morphology, pore structure and particle size distribution of SH-MgO and SC-MgO were analyzed. Besides, the phosphate removal performance and mechanisms were also investigated. The specific surface area of SH-MgO and SC-MgO was 98.03 and 62.35 m2 g−1, respectively. The corresponding average particle sizes were 211.98 and 19.56 μm. The phosphate adsorption followed the Vermeulen model and thus the rate of adsorption was limited by the intraparticle diffusion. The high affinity and selectivity of SH-MgO and SC-MgO for phosphate implied their great potentials in practical application. The EPR results demonstrated the presence of large numbers of oxygen vacancies in SH-MgO and SC-MgO. The phosphate removal mechanisms mainly included oxygen vacancy capture, electrostatic attraction, surface precipitation and inner-sphere complexation. This study provided a new strategy for facile preparation of oxygen vacancy-rich magnesium oxide, which was extremely significant for advanced removal of phosphate to reduce eutrophication.

A process to utilize lithium and magnesium resources from low-magnesium salt lake brine through extraction and CO2 stripping

The lithium resources in Tibet's salt lake account for more than 31 % of China's total, featuring a low magnesium-to-lithium ratio with its carbonate-type salt lakes representing a unique resource of the region. When extracting lithium from low-magnesium salt lakes (carbonate-type salt lakes) using a β-diketone system, it is common practice to add alkaline reagents at the front end to precipitate and remove magnesium. This study utilizes the LIX54/TRPO-ADD-1 system for the co-extraction of lithium and magnesium from the brine of the Jiezechaka salt lake, employing CO2 for stepwise stripping to separate lithium and magnesium, using a weak acid instead of a strong acid for stripping to avoid impacting Tibet's fragile ecological environment. By controlling the pH with varying amounts of CO2, an extraction efficiency of 92.54 % for lithium at pH=8.5 and an A/O = 1:5, and complete stripping of magnesium from the loaded organic phase at pH=7 with an A/O = 1:3.2 over three theoretical stages was achieved. This new process omits the front-end magnesium precipitation step, offering a new avenue for the separation of lithium and magnesium in salt lakes and the resource utilization of magnesium.

Fate of Ca2+ and metal impurities of a typical coal fly ash in amino acid mediated CO2 mineralization and simultaneous CaCO3 recovery

CO2 mineralization is a promising technology to achieve a waste-to-resource chain by integrating CO2 sequestration and alkaline solid waste utilization. Amino acids as a multifunctional reagent was proposed to avoid the extensive consumption of acid and alkaline reagents in traditional processes. However, the detailed interaction between Ca-bearing minerals and amino acids are still not fully understood, as well as migration pathways of metal impurities. To fill these gaps, this paper investigated the leaching and carbonation behaviors of Ca2+ and metal impurities of a typical coal fly ash (CFA) at various reagent types, reagent concentrations and leaching temperatures, thereby exploring the fate of these metal impurities. Results showed that the leaching and carbonation of Ca2+ was influenced by various aspects such as initial pH, reagent pKa, complexation, and pH buffering. The CaCO3 products obtained from glycine (Gly) and alanine (Ala) were vaterite due to the stabilizing effect of these amino acids on vaterite preventing it from converting to calcite. The optimal reaction conditions were 1.0 M Gly and leaching temperature of 35 °C with 26.63 % leaching efficiency, 56.08 % carbonation efficiency, and 42.6 g/kg vaterite yield. In addition, Ala induced an unexpected high leaching efficiency of Cd (75.79 %), Pb (76.08 %), and Zn (41.62 %), respectively, indicating promising mitigation of the environment risk of leached residue and valuable metal recovery from CFA. Although Gly displayed limited metal leaching efficiency at 1.0 M and 25 °C, increasing leaching temperature induced a remarkable enhancement of Cd and Pb leaching, which were 88.54 % and near 100 % at 35 °C, indicating promising mitigation of the environment risk of leached CFA. However, the high binding affinity of amino acids to impurity metals led to the low purity of CaCO3 product. This study derives the migration pathways of various metal ions during the mineralization and utilization of CFA, making it of great significance for the resource management and utilization of solid wastes.

Alternatywne podejście do usuwania/odzyskiwania wybranych metali z wody kopalnianej wypływającej z zalanej kopalni syderytu Nižná Slaná

The objective of this work was the application of innovative method for metals recovery from metalliferous mine water released from the flooded siderite ore deposit Nižná Slaná. Although the metals contained in mine drainage are considered environmental pollutants, they may also be recognised as valuable resources. Several techniques can be used to obtain them by precipitation. Conventional processes using alkaline reagents produce huge amounts of mixed sludge with appropriate storage and management requirement, void of possibility of individual metals subsequent processing. This study examined the feasibility of Fe and Mn selective retrieval from real mine water. After oxidation and partial precipitation of iron using hydrogen peroxide, precipitation by sodium hydroxide was applied to the residue iron removal from mine water. In the next step potassium permanganate was used to eliminate manganese by oxidative precipitation. ORP and pH values of processed mine water was recorded in the course of oxidation/precipitation processes. The morphology and elemental composition of obtained products were studied by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). The recovery efficiencies of Fe and Mn from mine water reached 99.87 % and 99.25%, respectively. Target metals were removed with high selectivity to levels that comply with environmental requirements.

Effect of Alkaline Reagents on Impurities in YSZ Nanoparticles Synthesized via Supercritical Hydrothermal Method

Effect of Alkaline Reagents on Impurities in YSZ Nanoparticles Synthesized via Supercritical Hydrothermal Method

Adsorption of cobalt isotope from liquid radioactive waste by carbon nanostructured materials of thermochemical activation of sludge-lignin

One of the urgent problems of modern industry is the accumulation of waste. Waste from the nuclear industry is liquid radioactive waste, pulp and paper industry is sludgelignin. To solve the problem of waste accumulation in these industries, a method of selective purification of liquid radioactive waste by waste products of the pulp and paper industry is proposed. Pyrolysis is an effective way of processing sludge-lignin, as a result of the activation of the pyrolysis product by alkaline reagents, activated carbons were obtained in laboratory conditions, which presumably can selectively extract isotopes of radionuclides from liquid radioactive waste. In the conducted study, the ability of carbon nanostructured materials of thermochemical activation of sludge-lignin to extract the isotope Со27 59 in the form of an ammonia complex was studied. The influence of the pyrolysis conditions: temperature (T), time (T) and dosage of the activator (D) on the response functions: monolayer capacity, heat of adsorption, the value of the maximum adsorption and the characteristic adsorption energy, which can be used to judge the porous structure of activated carbon. The method of the planned experiment is applied — rotatable central composite plan. For clarity, response surfaces are constructed based on experimental data. The analysis made it possible to develop practical recommendations for conducting the pyrolysis process in order to obtain a marketable product — activated carbons from sludge–lignin.

A complete and sustained organic/inorganic reaction mechanism of Baeyer’s test

The Baeyer’s test for unsaturation has been used in Qualitative Organic Analysis for a long time. However, if an alkaline reagent is used, compounds having an active hydrogen (carbon acids) also give a positive test with potassium permanganate, detracting the test for unsaturation. The first steps of the reaction sequence have been described but the next stages are missing. These are very important because they involve the formation mode of the observed end product, brown manganese dioxide. In this communication, a complete and sustained reaction mechanism is provided for both reaction mediums, neutral and alkaline. It is in accordance with observed experimental facts. The missing steps are a redox reaction between hypomanganate and permanganate ions, and a second cyclic intermediate now formed with manganate ion. The instability of this intermediate leads directly to manganese dioxide and alkalinization of the neutral medium, as observed experimentally.

Geopolymer synthesis and performance paving the way for greener building material: A comprehensive study

Ordinary Portland Cement (OPC) is renowned for its robustness and endurance in construction, but its manufacturing process incurs substantial energy consumption and leads to significant carbon dioxide emissions. Geopolymers (GP), conversely, represent a synthetic material derived from industrial by-products like calcined materials and slag. This study employs a diverse array of techniques to optimize the formulation of geopolymers and to evaluate their initial state (slump, reactivity) and mechanical characteristics (mechanical strength, density). Materials used are a combination of metakaolin (MK), granulated blast furnace slag (GBFS), and potassium silicate (K2SiO3) as an alkaline reagent (AR). The findings indicate that geopolymers exhibit strength akin to that of Portland cement (even better at early ages, between +16% to +88% higher), thereby positioning it as a credible substitute. The examination of the microstructure through methods such as nuclear magnetic resonance (NMR), Fourier transform infrared (FTIR), X-ray diffraction (XRD), and Thermogravimetric analysis (TGA) reveals that the synthesized material possesses a stable interconnected polymeric 3D-structure. Furthermore, mercury porosity analysis demonstrates the presence of finer pores (nanometric) consistent with a densely packed and closely-knit micelle structure. This study demonstrates that geopolymers blend comprising calcined earth, metakaolin, and slag holds promise as a viable alternative to OPC.

Antimicrobial and antioxidant activities of lignin by-product from sugarcane leaf conversion to levulinic acid and hydrochar

To enhance the sustainability of lignocellulosic biomass utilization process, a significant attention is given to a high-value lignin byproduct of this process. Herein, antimicrobial, antioxidant, and physicochemical properties of lignin in black liquor extracted from sugarcane leaf (SCL) for levulinic acid (LA) and hydrochar production were investigated. The lignin was extracted from SCL through an alkaline pretreatment process using 5–25 wt% of either NaOH or KOH at 120–160 °C. Disk diffusion susceptibility tests, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) revealed that the SCL lignin is effective against Gram-positive bacteria (S. aureus) rather than Gram-negative bacteria (E. coli and S. typhimurium). Different alkaline reagents marginally affected the antimicrobial and antioxidant activities of the lignin. Py-GC/MS analysis results determined that the SCL lignin contained mainly p-hydroxyphenyl (H) and guaiacyl (G) with a small amount of syringyl (S) lignin. Furthermore, the structural alterations and linkages of SCL lignin during alkaline pretreatment were examined using 2D-HSQC NMR, providing valuable insights into the transformation processes. The conversion of delignified SCL to LA through a catalytic hydrothermal process using various acid catalysts indicated that the alkaline pretreatment could enhance LA yield with a maximum yield of 33.4 wt%. Additionally, fuel property characterization of the hydrochar co-product from LA production determined that the hydrochar can be used as a coal substitute.

Use of metakaolin with a low surface area and rich in quartz and iron as a precursor in the production of structural alkali-activated concrete

Pumpable and machineable alkali-activated structural concretes are made using low-reactivity metakaolin with high quartz and iron contents. The effects and interaction of alkaline concentration (NaOH - 8, 10, 12, 14, and 16 M) and ratio of alkaline reagents (Na2SiO3/NaOH - 1.0, 1.5, 2.0, 2.5, and 3.0) on their properties were accessed using 2k complete factorial design. Higher concentrations of alkaline solutions resulted in faster hardening, decreased material deformation, and increased mechanical strength, with higher elastic modulus, lower damping, lower water absorption, and porosity. With time, the elastic modulus increased, and the dynamic damping decreased, suggesting the homogeneous formation of alkaline-activated products, confirming the proper configuration of the hardening process. The factorial design allowed for determining the ideal dosage for producing the material, indicating that the alkaline concentration (NaOH) should be 10 M and the Na2SiO3/NaOH ratio should be 2.5. They analyzed the possible combinations that allowed obtaining a material with adequate characteristics for the structural application.

Process performance and precipitate quality of phosphorus recovery by struvite precipitation in a fluidized bed reactor using a MgO industrial by-product

Phosphorus recovery through struvite precipitation has gained interest due to the potential use of struvite as a fertiliser, with fluidised bed reactors being a popular technology for carrying out the process. Struvite precipitation requires a magnesium source and an alkaline reagent. This research uses a low-grade magnesium oxide (LG-MgO) industrial by-product with a 56 wt% of MgO as magnesium source and an alkaline reagent to lower operating costs and value-add an industrial by-product. LG-MgO is poorly soluble in water, but its solubility increases significantly when dissolved in anaerobic digestion supernatants due to its circumneutral pH and high buffer capacity. Phosphorus precipitation was carried out in a laboratory-scale fluidised bed reactor where three operating variables (i.e. P:Mg molar ratio, feed inlet position, and recirculation flow rate) were studied to determine the LG-MgO impact on precipitate struvite content. Experimental results showed a high struvite content in all precipitates, close to the values reported for pure magnesium sources. The P:Mg molar ratio influenced precipitate composition. The percentage of struvite in the precipitate were 75–82 wt%, 85–88 wt%, and 75–76 wt% for the P:Mg ratio of 1:0.5, 1:1 and 1:3, respectively. The feed inlet position (side or bottom) also had an impact on precipitate struvite content when the P:Mg molar ratio was 1:3, but not for the other molar ratios. The recirculation flow rate did not have a significant impact on precipitate struvite content.

Physical and mechanical properties of meta-halloysite-based geopolymer mortars

Geopolymers are amorphous materials produced by the polymerisation reaction between an aluminosilicate precursor and an alkaline reagent or by activation with phosphoric acid. The aluminosilicate raw material used in the manufacture of geopolymers an be industrial waste, such as fly ash or volcanic ash, blastfurnace slag, or it can be obtained from natural raw materials, such as metakaolin and meta-halloysite. The work aimed to select the composition of an activator for the production of meta-halloysite geopolymers with optimum physico-mechanical properties such as specific and bulk density, porosity, weight, and bulk absorption, as well as flexural and compressive strength. A two-factor experimental design was employed to determine the composition of the alkaline activator for geopolymer mortars, with sodium hydroxide solution molar concentration and sodium silicate to NaOH ratio as variables. Research has shown that increasing the amount of sodium silicate relative to the mass of a 12M NaOH solution in the activator solution improves the compressive strength of geopolymers by 36.8%, while an increase in flexural strength of 14.2% was achieved. As the molar concentration of caustic soda in the activator solution increases from 19.0 to 24.5%, the porosity of geopolymer mortars decreases. The reduction in the ratio of water glass to sodium hydroxide and the reduction in the molar concentration of NaOH increases the mass and volume water absorption of the mortar. Further studies is necessary to determine the optimal mixture of metahalloysite geopolymer, taking into account its functional properties and durability.

Compositional Differences in Construction and Demolition Wastes (CDWs) for Geopolymer Mortars: A Comparative Study Using Different Precursors and Alkaline Reagents

In the view of the recycling and upscaling processes of waste materials, three different precursors, namely metakaolin, fly ash and volcanic ash, were mixed with Na- or K-silicate to produce binders aimed for the synthesis of geopolymer mortars based on construction and demolition wastes (CDWs). These later, used as aggregates in amount of 50 wt.%, were sampled in two geologically different Italian areas. A comparative study was carried out through a multidisciplinary approach using mineralogical–chemical analyses and physical–mechanical tests for the characterization of six binders and twelve mortars. The aim was to verify the effects of CDW interactions on binders as well as the extent of their compositional influences on the final properties. The chemical and mineralogical results evidenced strong compositional differences among the CDWs, differently influencing the physical–mechanical performances (i.e., compressive strength, density, water absorption and porosity) of the mortar samples. Regardless of the types of precursors and CDWs used, a better influence of K-silicate than sodium on the synthetised samples was observed. Furthermore, the higher versatility of metakaolin mortars with any type of CDW used was noted. Contrary, fly ash and volcanic ash mortars showed better properties with CDWs based on their high silica content and volcanic minerals. The study highlighted the critical roles of the CDW composition and precursor selection in mortar production. It confirmed that CDWs can be recycled for geopolymeric synthesis through proper characterisation and binder selection. Optimising these parameters allows for the successful integration of CDWs into geopolymeric materials. This process supports the advancement of a circular economy in the construction industry.

The optimization of sodium hydroxide (NaOH) pre-treatment for reducing sugar production from rice husk using response surface methodology (RSM)

Lignocellulosic biomass is an abundant renewable resource which amounts to 1.3 billion tonnes per year and can be used in a variety of sustainable applications. It is primarily made up of tightly bound cellulose, hemicellulose, and lignin. However, hemicellulose dissolution and delignification pose significant challenges to the utilisation of reducing sugar. To solve this issue, alkaline pretreatment was utilised. The aim of lignocellulosic biomass pretreatment is to break down the complex structure of the biomass and provide better access to the components that can be converted into useful reducing sugar. Response Surface Methodology (RSM) was used to identify the optimal values for the factors influencing the pretreatment. The optimisation parameters were sodium hydroxide concentration (1 – 4 % w/v), pretreatment time (15 – 60 minutes), and solid loading (6 – 16% w/v). Rice husk, which was used as biomass, was hydrolysed enzymatically to produce reduced sugar. The optimum conditions for producing the highest reducing sugar of 15.18 mg/mL from rice husk were 1.67% w/v sodium hydroxide pretreatment, 59.44 minutes of pretreatment time, and 7.67% w/v solid loading. As a result, less alkaline reagents can be used with a longer pretreatment time, thus lowering the cost of pretreatment. Therefore, this shows that RSM was one of the best methods to replace the conventional technique for optimising the parameters of rice husk alkaline pretreatment for reducing sugar production.

Heterocycle compounds synthesized by amide ligand-promoted copper salt catalyzed construction of C-O(S) bonds.

We introduce a mild method for the ligand-promoted copper-catalyzed coupling of 2-halophenol to construct DBDO using cost-effective copper salts, ligands, and alkaline reagents. This method cleverly makes 2-bromophenol complete the Ullman reaction twice, achieves efficient C-O(S) bond coupling and intermolecular cyclization, and yields high amounts of oxygen(sulfur)-containing six-membered ring products. Less reactive 2-chlorophenol was also applied in this catalytic system. The application range of the copper-amide catalytic system was further expanded. Moreover, the success of a gram-scale reaction demonstrated that this operationally simple process is scalable.