Sensitivity Analysis Of Vynyl Sulphone And BisMonochlorotriazine Reactive Groups Of Reactive Dyes

Reactive dyes contain different types of reactive groups which have different levels of sensitivity. Reactive dyeing is carried out by exhaust method on cotton knit fabric. A trichromatic combination is chosen containing vinylsulphone and bis-monochlorotriazine reactive groups. Dyeing of fabric is carried out with standard condition and variation of the conditions (electrolyte concentration, pH, exhaustion time, fixation time and M:L). Colorimetric data (DE*) is produced by comparing the difference between standard shade and the resulting shades by using spectrophotometer. Between the investigated reactive groups of reactive dye bismonochlorotriazine shows lower sensitivity in other terms higher robustness than vinyl sulphone

Evaluating lithium slag for geopolymer concrete: A review of its properties and sustainable construction applications

This comprehensive review paper evaluates lithium slag (LS) as a promising precursor for geopolymer concrete, focusing on its workability, strength, durability, and microstructure. In the context of sustainable construction, LS emerges as a vital alternative to conventional cementitious materials, primarily due to the environmental concerns associated with cement production, such as substantial greenhouse gas emissions and air pollution. Geopolymer technology utilizes alkali activators and aluminosilicate-rich materials, offers a reduced environmental footprint and shows comparable performance to traditional cement-based concrete. In particular, LS has gained attention for its potential as an aluminosilicate precursor material in geopolymer concrete. This review investigated the recent advancements in LS-based geopolymers, exploring various processing techniques like mechanical activation, calcination, and chemical treatment to optimize LS geopolymerisation and enhance early strength development. The incorporation of binary/ternary aluminosilicate material is also discussed, aiming to improve crucial properties such as workability, strength, durability, and microstructure. The needs for comprehensive research into LS-based geopolymers to achieve their full potential in sustainable construction, promoting an environmentally friendly approach and contribution to a circular economy in the construction industry are highlighted

Assessment of lithium slag as a supplementary cementitious material: Pozzolanic activity and microstructure development

In this study, lithium slag was utilised as a supplementary cementitious material (SCM) to develop pozzolanic activity and reduce CO2 emissions related to cement production, with a focus on comprehensive chemical tests and microstructural assessments. Lithium slag was primarily characterised through laser particle size analyser, X-ray fluorescence, X-ray diffraction, scanning transmission electron microscopy coupled with energy dispersive X-ray spectroscopy, and thermogravimetry. These tests indicate that lithium slag holds 31.6% amorphous phase with rich aluminosilicate minerals, making it an excellent candidate as pozzolan. The unsaturated lime and electrical conductivity pozzolanic activity precursor tests evaluated the potentiality of using lithium slag as a low carbon pozzolan. The optimum percentage of lithium slag as a supplementary cementitious material was determined from Frattini, strength activity index, and R3 tests by replacing 0–60% cement. Results show that 40% lithium slag mortar could achieve 93% strength activity index in 28 days. The microstructure development of lithium slag was assessed and ettringite, monocarboaluminate, and intermixed calcium aluminosilicate hydrates were formed at 56 days

Copper heap leach residue aggregates in concrete: Properties and performance

This study assesses the feasibility of using copper heap leach residue (CHLR) as a sustainable alternative to natural aggregates in concrete production. The CHLR possesses flaky-angular shape grains with rough surface texture and microcracks, crystalline silica of 51.6 %, 6.1 mg/g silt-clay with a median particle size of 4.3 mm, and it becomes suitable for the partial replacement of natural fine and coarse aggregates after removing 4.2 mg/g fines through 60-minute wash. Concrete containing 25–75 % CHLR aggregates met design slump and air content of 125±25 mm and 2±0.5 %, respectively, while also demonstrating a negligible 2.9 % reduction in fresh density and 2.8 % increase in compaction factor. Concrete containing 50 % CHLR as a partial replacement of natural coarse and fine aggregates achieved compressive strengths of 47.3 MPa and 45.1 MPa at 28 days, while the compressive strength of control mix was 46.7 MPa. The mechanical properties significantly declined at 75 % CHLR incorporated concretes. The BSE-EDS analysis highlighted improved interfacial transition zone for CHLR aggregates with minimal microcracks at early age compared to the natural aggregates but developed interfacial transition zone microcracks with prolonged curing leading to a decline in mechanical strength development