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This paper aims to improve the adsorption capacity of sugarcane bagasse (SCB) as a low-cost, attractive and effective adsorbent for dye removal from wastewater.

SCB is a cellulosic material; it was chemically modified with compounds containing cationic groups. The adsorption efficiency of unmodified and modified SCB was investigated with anionic dyes by studying various factors that affect modified SCB and adsorption.

X-ray diffraction, FT-IR spectra and nitrogen content were used to confirm the effect of existence of quaternary ammonium groups on modified SCB. The morphological structure of the modified and unmodified SCB has been demonstrated using electronic scanning microscopy.

The modified SCB was chemically treated by Quat 188, which is commercially available in the solution of 3-chloro-2-hydroxypropyltrimethyl ammonium chloride.

Grafting cationic function groups on the surface of sugarcane by cationization treatment enhances its adsorption efficiency for anionic dyes.

The main value of this research was indicating a clear difference in the appearance of unmodified and modified SCB surfaces. Furthermore, it can be determined that the modified SCB absorbs more of the dyes.

The purpose of this paper is to evaluate the efficiency of modifying reactive azo dyes using pyrazolo[1,2‐a]pyrazole fused systems as the chromophoric moiety which could satisfy many and varied criteria drawn from economic, synthetic, physicochemical and fastness properties.

Six novel heterocyclic disazo reactive dyes were prepared, containing monofunctional sulphatoethylsulphone (SES) and hetero‐bifunctional monochlorotriazine (MCT)/SES reactive groups. Dyes intermediates based on 4‐arylazo‐1,5‐dioxopyrazolo[1,2‐a]pyrazole chromophoric moieties are initially synthesised and coupled with two different diazonium salts having the aforementioned reactive groups, thus yielding the new target reactive dyes. The synthesised dyes are applied to cotton, wool and silk fabrics under the typical exhaust dyeing conditions and their dyeing properties were investigated.

The results assessed for dyeing indicate high‐quality dyeing properties. However, the heterobifunctional MCT/SES dyes showed higher exhaustion and fixation values, colour yields and fastness properties than those of the monofunctional SES dyes.

The method developed provided a simple and practical procedure for producing fused pyrazolo[1,2‐a]pyrazole disazo chromophoric systems that afford valuable reactive dyes. In addition, the dyes intermediates based on 4‐arylazo‐1,5‐dioxopyrazolo[1,2‐a]pyrazole as well as their disazo counterparts could be applied as acid dyes to wool and silk.

The method for producing novel disazo reactive dyes could find numerous applications for affording a variety of reactive dyes with different binding linkages and structural reactivity. These could be valuable as reactive dyes with different colour shades.

Enzymatic treatment of jute fabrics with neutral cellulase enzymes is investigated systematically. The factors affecting enzymatic treatment including, time, liquor ratio, temperature and enzyme concentration are also examined. The hydrolyzed pretreated surfaces of jute fabrics were characterized by scanning electron microscope (SEM), weight loss (WL) and wettability (Wet) tests. WL% and Wet were found to increase as the time, temperature and cellulase concentration increased. SEM images showed that the surface of the treated fabrics was smoother and more polished than that of the untreated fabrics after being subject to optimal treatment conditions.

In contrast, rough surface, fibrillation, surface pilling and multicellular were observed in the images of the untreated fabrics. The dyeing behavior of both untreated and enzymatically treated jute fabrics with reactive dyes was also evaluated under different dyebath conditions. The measured exhaustion and fixation percent showed a significant enhancement of the dyeability of biopolished pretreated fabrics compared to untreated fabrics. The results of fastness properties also indicate good washing, perspiration and rubbing fastness.

Nylon 6 fabric is pretreated with tannic acid and subsequently dyed with a cationic dye, Rhodamine B, from an aqueous dye solution and emulsion phase. The emulsion phase of n-hexadecane is emulsified by isopropyl alcohol and stabilized by Rhodamine B/tannic acid complex. Different factors affecting pretreatment and dyeing process have been studied. Changes of moisture regain, tensile strength, elongation and binding stiffness of the pretreated fabric are investigated.

The FTIR spectra of tannic acid pretreatment of nylon are also examined. The pretreated fabric with 10% owf tannic acid shows a slight increase in the tensile strength and elongation percentage. A higher moisture regain and binding stiffness are observed with increases in the amount of tannic acid. The results also indicate that the pretreatment for cationic dyed nylon 6 fabrics with tannic acid promote a higher dye uptake and cationic dye-based emulsion system with better fastness properties relative to those of the dye solution based system. A further improvement in wet fastness is secured by an aftertreatment of all dyed fabrics with a commercial anionic fluorescent whitening agent, Uvitex^® RSB 150%.

The purpose of this study is to use liposome technology in the treatment of fabrics textiles because of its efficient energy saving, reducing time and temperature.

The newly prepared lecithin liposome was used to encapsulate dyes for the purpose of increasing dyeing affinity. Different ratios of commercially available lecithin liposomes (1%, 3%, 5% and 7%) were used simultaneously in the dyeing of cotton and wool fabrics. The treated fabrics (cotton and wool fabrics) were confirmed using different analytical procedures such as scanning electron microscope (SEM), Fourier-transition infrared spectroscopy, ultraviolet protection factor, colour strength (K|S) measurements and fastness measurements.

The results show that increasing liposome ratios in dyeing baths leads to increased dyeing affinity for cotton and wool fabrics compared with conventional dyeing without using liposomes. In addition to that, the colour strength values, infrared spectra, SEM and fastness properties of non-liposome-dyed fabrics and liposome-dyed fabrics were investigated.

The research paper provides broad spectrum of green encapsulation fabrics using liposome technology to perform the dye stability, dye strength and fastness.

The purpose of this paper is to generate nitrogen-containing groups in the cotton fabric surface via low-temperature nitrogen plasma as an eco-friendly physical/zero-effluent process. This was done for rendering cotton dye-able with Acid Blue 284, which in fact does not have any direct affinity to fix on it.

Dyeing characteristics of the samples such as color strength (K/S), fastness properties to light, rubbing and perspiration and durability, as well as tensile strength, elongation at break, whiteness, weight loss and wettability in addition to zeta potential of the dyed samples, were determined and compared with untreated fabric. Confirmation and characterization of the plasma-treated samples via chemical modifications and zeta potential was also studied using Fourier transform infrared spectroscopy (FTIR) and Malvern Zetasizer instrumental analysis.

The obtained results of the plasma-treated fabric reflect the following findings: FTIR results indicate the formation of nitrogen-containing groups on cotton fabrics; notable enhancement in the fabric wettability, zeta potential to more positive values and improvement in the dyeability and overall fastness properties of treated cotton fabrics in comparison with untreated fabric; the tensile strength, elongation at break, whiteness and weight % of the plasma treated fabrics are lower than that untreated one; and the durability of the plasma treated fabric decreased with increasing the number of washing cycles.

The novelty addressed here is rendering cotton fabrics dye-able with acid dye via the creation of new cationic nitrogen-containing groups on their surface via nitrogen plasma treatment as an eco-friendly and efficient tool with a physical/zero-effluent process.

This work aims to increase the dyeability of nylon 6 with basic dyeing through the treatment of the fibre with available and cheap nanomaterials, namely; nano bentonite using an economic and simple method.

Different amounts of nano clay, namely, nano bentonite were dispersed in distilled water using an ultrasonic homogenizer for 1 h. Nylon fabrics were treated with different concentrations of dispersed nano bentonite (1%, 2%, 3%, 4%, 5% wt/v). After half an hour, the samples were padded using SVETEMA laboratory padding system. The padding pressure was adjusted at 3 bar to allow a pickup of 100%. The padded samples were dried at 80°C for 5 min and cured at 160°C for 3 min using ROACHES laboratory thermos-fixation. The cured samples were then washed with running water and left to dry at room temperature.

The obtained results indicated that the modification of polyamide 6 fibres with nano bentonite had a great impact on their dyeing properties. The obtained shades, absorption behaviour and fastness properties were significantly enhanced. Based on these results, it was concluded that polyamide fabrics could be successfully dyed with basic dyes using economical dyeing conditions.

This paper introduces a new method the loaded the nano-clay on the synthetic fibres, which are nylon 6 to enhance the dyeability with cationic dyes using the physical method without changing the structure of the fibres.

The purpose of this paper is to synthesise, characterise and find out properties of some new bifunctional reactive azo dyes using pyrazolo[1,2‐a]pyrazole 3‐carboxylic acid fused systems as the chromophoric moiety, bearing good colour strength, lightfastness, and other favourable properties.

The dyes are synthesised by diazotisation, coupling and cyclisation reactions. Firstly, synthesised 4‐arylazo‐1,5‐dioxopyrazolo[1,2‐a]pyrazole 3‐carboxylic acid chromophoric moieties and coupled with diazonium salts having the aforementioned reactive groups, thus yielding the new target reactive. The synthesised dyes were applied to cotton and wool fabrics under the typical exhaust dyeing conditions and their dyeing properties were investigated. The structures of these dyes are characterised and confirmed by melting point, elemental analysis, infrared, ultraviolet‐visible spectroscopy (UV/VIS) and nuclear magnetic resonance (1H‐NMR) data.

The wavelength of maximum absorptions, molar extinction coefficients are strongly dependent on the electron donating ability of the substituents on the coupling moiety. The absorption bands of these dyes move towards longer wavelength as the polarity of the solvents and electron density of substituents on the coupling moiety increase. The dyes applied on cotton and wool showed higher exhaustion and fixation values, colour yields and fastness properties.

The method developed provided a simple producing fused pyrazolo[1,2‐a]pyrazole disazo chromophoric systems based on 4‐arylazo‐1,5‐dioxopyrazolo[1,2‐a]pyrazole 3‐carboxylic acid as well as reactive dyes applied on wool and cotton dyes.

In this paper, three series of pyrazolo[1,2‐a]pyrazole derivatives dyes are synthesised and characterised. They have not been registered in the literature previously.

This study aims to synthesise and characterise new reactive dyes based on thiazole derivatives which act as chromophoric moieties. These dyes were applied to cotton fabric, resulting in the dyed fabrics exhibiting good colour strength, light fastness and other fastness properties. The antibacterial activity of the dyed cotton fabric was evaluated against gram-negative and gram-positive bacteria.

The dyes were synthesised in two steps. First, the coupling compound was formed by adding H-acid solution to cyanuric chloride in an ice bath at pH 5 then adding 4-aminobenzenesulphonic acid portion-wise at room temperature and at pH 6-7. Second, different diazonium salts 4-phenylthiazol-2-amine (2a) and 4-(4-methoxyphenyl) thiazol-2-amine (2b) were coupled with the coupling compound at pH 5. The resultant monochlorotriazine (MCT)-reactive dyes (6a, 6b) were formed. The synthesised dyes were applied onto cotton fabric under typical exhaust dyeing conditions and their dyeing properties were investigated.

High antimicrobial activity, dye exhaustion and fixation yield on cotton fabric were recorded for each dye. All dyes showed high stability against washing, rubbing, perspiration and light fastness.

Dyeing of cotton fabric with these dyes which have higher fastness, higher exhaustion and higher antibacterial activity is considered one of the most important reactive dyes species.

The preparation procedure showed the synthesis of the novel MCT-reactive dyes derived from thiazole derivatives followed by the application of these dyes on cotton fabrics.

Use of reactive dyes will bring a number of benefits to society including higher fastness and higher antibacterial activity so, and these dyes can be used for dyeing cotton.

In this work, the new reactive dyes derived from thiazole derivatives were synthesised and their structures were confirmed by the analytical and spectral data. Such compounds are considered to be excellent reactive dyes with different colour shades and higher antibacterial activity.

A try to find some useful applications for some products prepared from agricultural waste by mixing them with cement to act as reinforcement agents. The paper aims to discuss these issues.

Cement was mixed with microcrystalline cellulosic (MCC) fibres prepared from baggase, soaked in mixing water, followed by cubic pastes formation. The mixing was performed using different ratios of MCC; 0.5, 0.75, 1 and 3 per cent. The cement properties were followed at timed intervals, up to 90 days. The initial and final setting times of the pastes were determined. Bulk density, apparent porosity and compressive strength of the harden cement pastes were also identified. The hydration kinetic was followed by identifying free lime ratio and chemically combined water content. The structure of the hard cement pastes was followed by SEM, FTIR, DSC and XRD.

It was noticed that the weight of the prepared cement pastes using MCC was reduced, while the compressive strength was increased. In addition, lower ratios of MCC have shown better results at early ages of hydration and reported higher compressive strength than control. No interaction was reported between the fibres and cement constituents based on the performed analysis.

Different types of agricultural wastes can be compared in producing the best type of MCC for the same purpose of this research.

This piece of work has suggested a simple way to convert a product prepared from agricultural wastes in a small uniform size to a reinforcement agent to cement. Consuming this type of waste reduces the risks resulting from its burning at some countries such as Egypt.

MCC fibres have well-known binding properties and used successfully on wide range in medical applications for tablets production with low costs. These fibres have reduced the pastes weight and increased the compressive strength using low ratios of them. Moreover, there is no indication of a reaction between these fibres and cement constituents.