Aluminum Sulfate Research Articles

Application of titanium gypsum as raw materials in cement-based self-leveling mortars

There are studies on titanium gypsum (TG) as a cement retarder, cementing material, or the production of lightweight wall materials and roadbed materials, but the application of TG is still limited, the utilization of TG is in the stage of exploration. This work studied the possibility of recycling TG as raw materials for the preparation of cement-based (Sulphate Aluminate Cement and Ordinary Portland Cement) self-leveling mortars. The effects of TG on mechanical strength, fluidity, shrinkage, and wear resistance were carried out. With the help of XRD, TG-DTG, and SEM, the microstructural characteristics were investigated to determine the mechanism of TG. It was concluded that the 1 d compressive and flexural strength reached 9.6 MPa and 3.5 MPa, respectively, and the 28 d compressive and flexural strength reached 4.3 MPa and 17.9 MPa, respectively, when the mass ratio of Sulphate Aluminate Cement (SAC) and Ordinary Portland Cement (OPC) was 7:3, the TG content was 45 %. TG could significantly improve the shrinkage of the mortars to 0.10 %, which was far better than the standard requirements of 0.15 %, but reduce the wear resistance to some extent. The primary component of calcium sulfate dihydrate (CaSO4·2H2O) in TG can further react with the aluminum phase in cement to grow more ettringite, which can make the microstructure denser, thereby improving the strength and the deformation of the cement-based self-leveling mortars.

Alumina production: Historical development, issues, and solutions. Part 1

This study focuses on documenting the historical stages of aluminium and alumina production prior to the transition to a modern industry structure, involving the Hall-Héroult electrometallurgical process, and their technical significance for the contemporary metallurgical complex. It highlights the significance of these stages in the development of scientific knowledge related to alumina, aluminium, and their production technology when using chemical methods for obtaining metallic aluminium. The analysis includes aspects, such as classification, technical evaluation of the processes, and the raw material base. It is shown that the formation of scientific knowledge regarding alumina and aluminium is mainly associated with the practical need for using alum and, to some extent, clay minerals. Since the commencement of deliberate research into methods for aluminium production in its elemental state and virtually until the 1890s, aluminium was primarily produced using the metallothermal methods pioneered by Henri St. Clair Deville and his colleagues due to the high thermodynamic stability of aluminium compounds and the absence of affordable energy sources. It was found that from 1854 to 1890, the production of aluminium by chemical method was associated with the use of sodium aluminium chloride (NaCl·AlCl3), natural cryolite, or synthesised fluoride salts. Available technical reagents (aluminium sulphate, ammonia alum, and aluminium hydroxide), along with natural raw materials (cryolite, bauxite, and clay), were used as source materials in this period. The extraction and processing of bauxite were primarily associated with the production of alum and aluminium sulphate consumed by light industry. Although the demand for pure aluminium oxide was limited during the metallothermic production of aluminium, the driving force behind the advancement of modern technologies for alumina production was the demand for chemical products. This demand led to the development of technology for processing bauxite, which forms the foundation of the metallurgical complex in aluminium production using the Hall-Héroult electrometallurgical method.

Effect of Blanching Pre-Treatments on Sensory Quality of Dragon Fruit Peel Pickle

Present investigation entitled effect of blanching pre-treatments on quality of dragon fruit peel picklewas aimed to evaluate sensory quality of dragon fruit peel pickleduring storage. For preparation of dragon fruit peel pickle, an experiment was laid out with six blanching pre-treatments [without blanching (T1), water blanching (T2), 0.5% citric acid blanching (T3), 1.0% citric acid blanching (T4), 0.5% alum (potassium aluminium sulphate) blanching (T5) and 1.0% alum (potassium aluminium sulphate) blanching (T6)]. The prepared pickle was stored for a period of 6 month to analyse the sensory quality attributes at three month intervals. The results of the investigation revealed that dragon fruit peel pickle prepared from peel blanched in 1 per cent citric acid (T4) observed to have maximum colour, taste, flavour, texture and overall acceptabilityscore. Overall findings of investigation revealed that best sensory quality dragon fruit peel pickle can be prepared from peel when blanched in 1 per cent citric acid followed by curing in 8 per cent salt and addition of ingredients. The dragon fruit peel pickle can be successfully stored for a period of six months with minimum changes in sensoryquality.

Optimum Conditions for Enhancing Chitosan-Assisted Coagulation in Drinking Water Treatment

Coagulant aids are useful chemicals that enhance the efficiency of coagulation sedimentation treatment. For this purpose, it is necessary to choose safe chemicals to avoid various risks to the health of those who use the treated water. The use of chitosan, an abundant natural polysaccharide, as a coagulant aid is significant not only for safe water treatment but also for the effective utilization of unused natural water resources, which are mostly wasted. We experimentally determined the optimal treatment conditions for using chitosan as a coagulant aid in water treatment. The most efficient use was identified as adding chitosan at the stage of rapid stirring after the addition of coagulant accelerated initial dispersion. When used with the main coagulant polyaluminum chloride (PACl), the optimal concentration of chitosan was 0.8 mg L−1, as estimated using the ζ potential showing isoelectricity at the optimal chitosan concentration. Determining the chitosan concentration using the minimum ζ potential was also valid for estimating the optimum concentration of chitosan, which is an extension of the method used at much higher turbidity, as seen in wastewater. Thus, the ζ potential-based prediction of the optimum chitosan concentration was effective even when the effect of sweep coagulation, which is normally induced at higher turbidity, was negligible. The superiority of using the coagulant PACl in combination with chitosan as the coagulant aid was demonstrated by comparing the in situ-observed coagulation process to cases with other coagulants and coagulant aids using direct time-series observation of the coagulation process. The use of chitosan with PACl was found to make the flocs easier to remove because it resulted in the largest mass fraction of the resultant floc sedimentation on the bottom of the vessel. In this study, using the PACl coagulant in combination with chitosan as the coagulant aid was found to be as viable as using the current popular combination of aluminum sulfate and polyacrylamide. Replacing polyacrylamide with chitosan contributed to reducing the potential risk to the health of those to use the treated water.

Low temperature hydrothermal processing to recover aluminum from nepheline syenite roast-leach residue

ABSTRACT Nepheline syenite is primarily an alumino-silicate rock which contains a major amount of potassium and aluminum. After potassium recovery through chloridizing roasting followed by water leaching method, the roast leach residue of nepheline syenite was considered for the aluminum extraction process due to its ample aluminum content. Sulfuric acid is chosen over other acids as it prevents the leaching of calcium. A 2^3 full factorial design was employed to study the effects of acid concentration, time, and temperature. Furthermore, to enhance the recovery and to forbid the leaching of silicon, autoclave leaching was preferred. Iron is generally leached with aluminum in the acid leaching process which could be removed effectively by pH adjustment. The leached liquor obtained after purification is evaporated by using a hot water bath. The liquor concentrated on slow evaporation to a point where aluminum sulfate started precipitating. Then, the concentrated liquor was kept overnight at 8°C in a cooling incubator. Aluminum sulfate was produced with 99.80% purity.

Technical and environmental properties of recycled aggregates produced from concrete sludge and excavation materials

This study presents a Re-Con Zero dry washing technology used to produce recycled aggregates from concrete sludge (RCZ) and combined as a feedstock in wet recycling excavation materials (EM) for unbound applications. A two-component admixture i.e, high water absorbing polymer and aluminum sulphate was used in producing RCZ. RCZ0, RCZ50 and RCZ100 were produced with EM within the range 0–100%. Analysis by the Los Angeles (LA) and micro-Deval (MD) test demonstrated RCZ to be of high-quality, hence a clear trend of improved performance as the content increased was observed in the LA and MD values. X-ray diffraction analysis performed on original and pulverized residues (<1.6 mm) showed that feldspar, quartz, phyllosilicates (mica and chlorite) and minor amounts of pyroxene (diopside) were present together with paste minerals such as portlandite and residual clinker, and calcite. Acid solubility results demonstrated the relation to increased paste content as particle size reduced. This observation was more prevalent in < 1.6 mm RCZ fraction which further indicated the significant amount of remained paste after wet treatment. Low levels of the content of chemical species of potential concern were in general found and were mostly complying to Norwegian regulations. Total Cr exceeded the criteria of 100 mg/kg, but the leachable Cr(VI) was not detected which showed that remaining Cr after recycling process was present mostly on the trivalent form. This indicated low leaching of Cr upon carbonation and a decrease in pH.

A novel mesoporous carbon nanospheres-based adsorbent material with desirable performances for dyes removal

Nowadays, the reduction of dye contaminants in the aquatic environment has attracted widespread research attention. In this work, a novel mesoporous carbon nanospheres (MCNs)-based material as an adsorbent for dye removal was achieved by the carbonization of a composite of sucrose and aluminum sulfate without involving any hazardous activators. The as-obtained MCNs were analyzed by TG, XRD, FESEM, TEM, Raman, BET and XPS, meanwhile the batch experiments of Congo red (CR), Malachite green (MG) and Methylene blue (MB) on the MCNs were conducted to explore the impact of adsorption conditions on the adsorption process, respectively. Results show that the MCNs exhibit a uniform spherical morphology as well as partially graphitic structure with a large surface area of 449.25 m2/g, a relatively narrow pore size distribution and a high pore volume of 0.57 cm3 g−1. The unique porous structure of the MCNs endows it with high adsorption capabilities for dyes, including CR (1726.60 mg g−1), MG (980.55 mg g−1) and MB (708.82 mg g−1), suggesting its high adsorption capability for both anionic and cationic dyes. Meanwhile, the adsorption process is demonstrated to follow the Langmuir model and pseudo-second-order kinetic model, respectively, and the main adsorption mechanisms may involve pore filling, π-π conjugation, electrostatic attraction and hydrogen bonding. Furthermore, the as-synthesized adsorbent displays good recyclability performance for remaining relatively high sorption performance even after five regeneration cycles.

Depression of Arsenopyrite during Collectorless Flotation in Presence of Aqueous Metal Ions and Inorganic Compounds

Currently, the depression of arsenopyrite during the flotation of base metal mineral sulfides is being continuously studied to reduce its presence in sulfide concentrates of economic interest. In this work, the influence of aqueous metal ions (Fe2+, Cu2+, and Zn2+) in concentrations of 5, 25, and 75 g∗ton−1; mixtures of aqueous chlorides (ammonium and magnesium) and aluminum sulfate (AS)–sodium silicate (SS); and the use of only ordinary Portland cement (OPC) in all concentrations of 0.05 to 0.6 g∗ton−1 during the collectorless flotation and depression of a single-phase majority of arsenopyrite was analyzed. The results revealed a decrease in the hydrophobicity; its depression was greater with the use of OPC. At the concentration of 0.4 g∗ton−1 at alkaline pH and a pulp potential of +0.067 V, in 0.5 min, its flotation was 15.4 % w/w and the cumulative recovery at 10 min was 46.4 % w/w. The arsenopyrite depression was as follows: OPC &gt; mixed chlorides &gt; ASSS. Fe2+, Zn2+, Cu2+ ions activate flotation arsenopyrite. The solids obtained during the flotation were characterized using FTIR, and the functional groups responsible for the depression of arsenopyrite were identified.

Optimization Rubbing Fastness in Lyocell and Silk Fabric Dyeing with Tinospora cordifolia using Box-Behnken Design and Citrus limon Extract with Potassium Aluminium Sulfate Mordants

The demand for environmentally friendly natural dyes has risen significantly. This study currently aims to assess the rub-fastness properties of silk and lyocell fabrics that have been dyed using Tinospora cordifolia stem extracts. This dyeing process involves the utilization of both Citrus limon and potassium aluminium sulfate as mordants. To achieve this objective, we have employed the Box-Behnken experimental research design for sample preparation. Our investigation delves into the influence of various processing factors, encompassing dye concentration, time duration, and temperature, on the rubbing fastness attributes of lyocell and silk fabrics treated with Citrus limon extract and alum mordant. The dye, sourced through an aqueous extraction method from Tinospora cordifolia stems, is subsequently employed in dyeing silk and lyocell fabrics, followed by mordanting using the meta-mordanting technique. The assessment of rubbing fastness quality is conducted using the standard test method AATCC 8 for both fabric types. Our experimental findings unveil a notable similarity in rubbing properties between lyocell and silk fabrics dyed with Citrus limon and those treated with potassium aluminium sulfate mordant. Intriguingly, fabric samples treated with Citrus limon mordants exhibit marginally enhanced rubbing (2 to 3 G to 5 G) results when juxtaposed with their counterparts treated with potassium aluminium sulfate mordant. Throughout the experimental course, it becomes evident that both temperature (35 °C, 50 °C, 65 °C) and time (40, 55 and 70 min) exert a significant influence on the wet and dry rubbing fastness characteristics of both silk and lyocell fabrics. Notably, as dyeing time and temperature increase, there is a corresponding rise in fabric dye uptake.

Exploration of effects by the ‘alum-glue solution’ on Xuan paper degradation using a 23 factorial design experiment

In the traditional Chinese conservation mounting process, it is well acknowledged that the alum-glue solution, composed of potassium aluminum sulfate [KAl(SO4)2·12H2O], gelatin, and water, is commonly used for paper sizing. In this study, its adverse effects when prepared in different ratios on the contemporary Xuan paper are explored, demonstrating certain negative influences on material properties and paper durability. We primarily characterized an extra-pure Xuan paper as a reference sample. Then, a 23 full factorial experiment was designed and performed to explore the effects of the three factors, i.e., KAl(SO4)2·12H2O (denoted as alum), animal glue or gelatin (denoted as glue), and water contents on rates of paper degradation [kΔ(1/DP)] and color changes (kΔL and kΔb). The results show that the unsized extra-pure Xuan paper sample has good stability due to appreciable alkaline reserve, weakly alkalinity, and no presence of transition metals. Fourier transform infrared (FTIR) spectra and scanning electron microscope (SEM) images demonstrate the presence of sizing. Given that the alum-glue solution has been widely used in paper conservation, the results in this study demonstrate the devastating role of KAl(SO4)2·12H2O and the protective effects of gelatin on durability of treated papers, verified by the DP-related data. Additionally, it was found that the presence of alum is mainly responsible for the lightness decrease of the treated papers, and animal glue plays a primary role in paper yellowing. The findings in this research can deepen our understanding of the rate of paper degradation and color changes for the Xuan paper treated with the alum-glue solution.

Performance optimization design of high ductility cement-based alkali-activated municipal solid waste incineration fly ash composite for rapid repair material

As a residue that results from the high-temperature incineration of urban household waste, municipal Solid Waste Incineration Fly Ash (MSWIFA) contains various harmful organic pollutants like dioxins and heavy metals. These contaminants pose significant health risks to humans, including deformities and carcinogenic effects. The focus of this study is the development of a High Ductility SAC Rapid Repair Material (HD-SACRRM) through MSWIFA as a partial replacement for Sulphate Aluminate Cement (SAC), so as to achieve high ductility, rapid hardening, and the strength required for pavement layers. The reactivity of MSWIFA is investigated by adjusting its content and the type and dosage of alkali-activators. X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM) tests are conducted to analyze the variety and microstructure of alkali-activated MSWIFA-SAC hydration products. Also, the efficiency of immobilizing heavy metal ions within the alkali-activated system is examined. Based on these findings, the proportions of HD-SACRRM are optimized. The experimental results demonstrate that the optimal conditions for MSWIFA reactivity are met when the MSWIFA content is 20% and the 30% soluble silicate with a modulus of 1.8 is present. The optimized conditions of HD-SACRRM are as follows: a 20% MSWIFA content, 30% soluble silicate with a modulus of 1.8, a water-cement ratio of 0.30, a 2.0% fiber volume fraction, a sand-cement ratio of 0.30, and 5% Li2CO3 as an early strength agent. After 48 h of curing as standard, the material exhibits a compressive strength of 45.7 MPa, an ultimate elongation of 2.70%, and an average crack width of 127.59 μm. The alkali-activated MSWIFA-SAC system generated more gels such as C-S-H and C-A-H, thus resulting in a dense microstructure that enhances both the capacity of heavy metal immobilization and mechanical strength. These findings shed some light on the recycling of MSWIFA solid waste and the repair of asphalt concrete road surfaces.

Ballasted flocculation pretreatment for mitigating ultrafiltration membrane fouling: Role of differently charged polyacrylamides at typical coagulant dosages

In this work, ballasted flocculation (without sedimentation) was suggested as a potential pretreatment for ultrafiltration to improve cake layer microstructure and mitigate membrane fouling. First, three representative aluminum sulfate (AS) coagulant dosages (including 1.0, 2.5 and 8.0 mg Al/L) were determined during preliminary testing to produce microfloc aggregates with negative, zero and positive zeta potentials at the coagulation stage of ballasted flocculation. Regardless of the applied coagulant dosage, not only ballasted floc size but also their strength and recovery abilities (following breakage) were dependent upon the selection of differently charged polyacrylamides (PAMs), likely due to the effect of PAM selection on polymer bridging and associated flocculation mechanisms. Second, comparisons of membrane flux decline and resistance distribution were performed to evaluate the importance of coagulant dosage and PAM type to cake layer formation and membrane fouling potential in the ballasted flocculation and ultrafiltration integrated process. The results demonstrated that the ballasted floc aggregates formed by ballasted flocculation pretreatment contributed to diverse structural characteristics of the fouled layer during their accumulation on the membrane surface, thereby affecting the degree of membrane fouling for various combinations of AS dosage and PAM type. Besides, the microsand particles involved in the formed layer could act as a skeleton of the cake layer structure, so their spatial distribution within the layer interior played a critical role in cake layer microstructure improvement, ultrafiltration efficiency enhancement and membrane fouling mitigation. In other words, the extent of steric-hindrance effects by ballasted floc aggregates should be emphasized in the formation of cake layer.

Ferrite-SCNTs Composite (ZFS) Embedded Nanostructured Cellulose Acetate Membranes - A Promising Sulphate Salts Rejecting Tool. Synthesis and Characterizations

Tailoring diverse characteristics of nanostructured cellulose acetate (CA) membranes by incorporating nanocomposite-tubes ZFS composed of zinc ferrites decorated over single walled carbon nanotubes (SCNTs) for desalination application, is presented in the current research. In situ coprecipitated route is adopted to synthesize ZFS composite filler that imparts morphological, structural, and thermal modifications in CA membranes. Phase inversion via immersion precipitation route has been adopted to synthesis mixed matrix membranes. Microstructural analysis divulges pore size tuning from 1µm to 5nm by increasing loading content of infused filler (ZFS) from 0 to 4wt.%. XRD and FTIR examinations verified the existence and linkages of impregnated composite nanotubes in the modified membranes. Increasing ZFS contents 1-4wt.% enhanced the thermal stability of host membranes up to 17°C in comparison to pristine CA membranes as proclaimed by thermal degrative investigations. Membranes’ performance is evaluated by deionized water flux and sulphate salts (aluminum and copper) rejection capabilities. The prepared membranes are highly effective in salts removal application as evident from 98% of aluminum sulphate rejection that emanates from micro to nano porosity transformation after increasing filler composite into the membrane matrices.

Наднормативні концентрації хлороформу та сульфату алюмінію у питній воді та їхній вплив на метаболічні процеси в організмі лабораторних тварини

Objective: determination of the nature and features of changes in biochemical indicators in the blood of animals under conditions of chronic exposure to different concentrations of chloroform and aluminum sulfate in drinking water in an isolated and combined state to substantiate the criteria for hygienic evaluation of their adverse effects on the body. Materials and methods: combined effect of chloroform and aluminum sulfate on biochemical indicators. Results: According to the results of biochemical studies, it should be noted that the most pronounced changes were observed in groups of animals that were exposed to CLF and Al in isolation at the level of 3 MPC and 5 MPC, and in groups of animals with combined exposure to the specified substances - CLF + Al at the level of 3 MPC аnd 5 MPC. A decrease in the content of AsT and an increase in the level of AlT in the above experimental groups of animals may indicate functional disorders of the liver, especially its enzymatic function. The indicated changes in the content of glucose and amylase in the blood as indicators of carbohydrate volume may indicate the activation of the processes of glycogenesis and glycolysis in the animal body, which may lead to functional disorders of the pancreas. Іt was established that the nature and severity of the effects depended on the nature of the influence of the studied factors (isolated or combined action), their MPC levels, and the time of exposure. Conclusions. The nature and features of changes in biochemical indicators in the body of experimental animals during a six-month chronic sanitary-toxicological experiment with isolated and combined effects of chloroform and aluminum sulfate in drinking water may indicate metabolic disorders in organs and changes in the intensity of regenerative processes at the cellular level in response to the adverse effects of toxicants. Such a tendency to imbalance indicators can be a kind of indicator of metabolic compensatory changes in the body under the influence of a complex of factors, depending on the current level and duration of action.

Sedimentation of bentonite suspensions under the influence of low molecular weight polymers based on amino ester salts

Among the available technologies for treating natural and wastewater from clay materials, coagulation/flocculation is the most common method due to its high efficiency, simplicity, and cost-effectiveness. Inorganic coagulants such as aluminum sulfate and ferric chloride, widely used as destabilizing agents for colloidal particles, have several significant drawbacks: low efficiency and toxicity. Organic reagents of both natural and synthetic origin are a good alternative. This work is devoted to the evaluation of the flocculation action of new reagents, which are low molecular weight polymers based on amino ester salts on clay suspensions, as well as the selection of their optimal concentration, providing the maximum sedimentation rate. Studies have shown that amino ester salts can be effectively used for the treatment of water-clay suspensions. An important factor is the nature of the anion used, which has a significant influence on the oagulation ability of esters. Thus, 40–50 % (wt.) aqueous solutions of amino ester chlorides added to clay suspensions in an amount not exceeding 0.1% (vol.) can be used to thicken clay suspensions. At the same time, aqueous solutions of amino ester bromides regardless of the concentration, introduced into bentonite suspensions of 0.1–0.4 % (vol.), contribute to improved sedimentation, reducing viscosity, and increasing filtration capacity. These results allow us to recommend the use of amino ester chlorides as athickener in the preparation of drilling muds for strengthening the walls of wells during drilling, and bromides – for flocculation of bentonite suspensions in oil production

The Effect of The Utilization of Gambier Processing Wastewater for Tannery with Variations of Alum and Tunjung on Physical Properties Test

The study involved variations in the percentage of alum and tunjung added as mordants, with percentages of 0%, 2%, 4%, and 6% used during the processing of wastewater from gambier. To evaluate the physical properties of tanned leather, the researchers followed the SNI 06-0463-1989-A. The findings indicated that using alum (aluminium sulfate) and tunjung (ferrous sulfate) as mordants affected the physical properties of tanned leather. Alum yielded better physical properties compared to tunjung, as evidenced by the higher tensile strength and flexural strength/elongation in the tanned leather treated with alum. The physical properties of tanned leather were found to be significantly influenced by the percentage of alum used, with higher percentages resulting in increased tensile strength and decreased flexural strength. The most effective treatment involved adding 2% alum, which suggests that combining gambier processing wastewater with alum can be a viable method for tanning leather. These findings demonstrate the potential for using alternative chemicals in leather tanning, which may offer benefits in terms of cost and environmental impact.

Performance Assessment of Descurainia Sophia Seed Extract as a Natural Coagulant in Combination with Aluminium Sulfate for Turbidity Removal in Water

Performance Assessment of Descurainia Sophia Seed Extract as a Natural Coagulant in Combination with Aluminium Sulfate for Turbidity Removal in Water

Early age strength of ambient-cured geopolymer mortars from waste concrete and bricks with different alkaline activators.

Background: The dataset in this work emanates from preliminary studies comparing early-age compressive strengths of geopolymer mortars produced from construction and demolition wastes (CDW) commonly found in Qatar using different alkaline activators. Methods: Waste concrete, waste bricks and steel slag - an industrial waste produced in large quantities in the country - were used as aluminosilicate sources. Waste concrete was used as fine aggregate (75 μm to 4 mm), while solid or hollow red clay bricks were used together with steel slag as aluminosilicate powders. Solid red clay brick (75 μm to 1.4 mm) was also used as fine aggregate in some mixes. Different alkaline activators including solid powder or ground pellet forms of Ca(OH)2, CaO, and Ca(OH)2-NaOH, NaOH-CaCO3 and Na2SiO3-Na2CO3-Ca(OH)2 mixtures were employed by just adding water. A few mixes included both solid powder Ca(OH)2 and viscous solutions of NaOH and NaOH-Na2SiO3 as alkaline activators. The geopolymer mortars also included small amounts of some other additives such as gypsum, microsilica and aluminium sulfate to enhance the geopolymerization and hydration process. Random proportions of the materials were considered in the range-finding experiments, and the mortars produced were tested for compressive strength. Results: The data show the 7-day compressive strengths and densities of the 40 mixtures considered with mostly ambient temperature (20°C) curing. It also shows such data for mixtures in which variables such as curing at 40°C, mixing with hot water at 50 - 60°C temperature, grading of waste concrete aggregates, and collective grinding of the powdered materials were considered. Conclusions: The dataset shows possible early-age compressive strengths of different geopolymer mortar mixture designs and the materials and mixture design methods that can be used to achieve desired early-age strengths from waste concrete and bricks.

Treatment of Endocrine Pollutants Upstream of the Wadis Tghat and Zhoun of the City of Fez by Coagulation-Flocculation (Morocco)

In recent years, the quality of the surface water of the city of Fez has deteriorated due to the development of various anthropic activities, ill-considered modernization, unregulated discharge of wastewater and solid waste. This is a worrying threat to human health and the environment. Previous studies on these wadis have shown that Tghat and Zhoun wadis are the most polluted [1]; [2]; [3]. Adequate treatment of effluents upstream is therefore of crucial importance. The objective of this study is to contribute to the treatment of endocrine pollutants discharged upstream of these two wadis after their characterization and monitoring of their pollutant load for six months (El Madani et al., 2019). The most polluted wadis of the city of Fez [2] by coagulation-flocculation.The results showed that these effluents have a medium faecal load and are loaded by organic pollution at the limit of biodegradability rich in nitrogen and phosphorus matter and a high metallic load with endocrine disrupting effect, mainly Cr, As, Pb and Cd.The treatment of these pollutants by coagulation-flocculation with aluminum sulphate of the effluents studied under optimal conditions of pH, a dose of coagulant and flocculant and coagulation and flocculation agitation speeds, allowed the reduction of almost all the organic matter and 90 to 96% of the metal load.

Activation behavior of the novel CO2 foaming agent for mining on fly ash

Although there have been many research results on the chemical activation of fly ash (FA) as a supplementary cementitious material (SCM) in cementitious materials. However, there is a lack of research on the use of CO2 foaming agent (sodium bicarbonate and potassium aluminum sulfate) to activate fly ash. In this experiment, the effects of CO2 foaming agent, sodium bicarbonate, and potassium aluminum sulfate on the activity of FA mixed paste were investigated. The mechanism of FA activation by activator was revealed by selective acid dissolution, QXRD, BSE-EDS statistical analysis, and quantitative analysis of TGA. The results showed that the remaining fly ash amounts of MG, SBG, and PASG after 28 days were 17.5%, 25.9%, and 43.3% lower than those of the control group, respectively. In addition, potassium aluminium sulphate promoted hydration to generate more CH to activate the FA. Sodium bicarbonate promoted hydration and produces more CH to activate FA by generating nano-CaCO3. The mixture of sodium bicarbonate and potassium aluminum sulfate took advantage of both nano-CaCO3 and potassium aluminum sulfate to promote silicate hydration to provide CH. As a result, the two synergistically activate FA. The above results show that CO2 foaming agents can be used not only as foaming agents to prepare lightweight materials, but also as chemical activators to activate solid waste. This will have a high practical application value.