Quantitative Analysis by IR: Determination of Chitin/Chitosan DD

FTIR spectroscopy has been widely used to quantitatively study the parameters of the chitin deacetylation. A new research on a Canadian chitin has shown that a degree of deacetylation (DD) of 90% has been reached with a base concentration of 12.5 M, a reaction time of 120 min, and a temperature of 110°C. In parallel, our study on Moroccan chitin allowed to reach 75%. A degree of deacetylation of 75% was obtained at T = 120°C and at CNaOH = 12 N in a single step for 6 hours. Another study followed by IR prepared the chitosan under pressure or under irradiation. Firstly, the compression method was used for preparing 100% deacetylated chitosan with less environmental pollution. The 100% fully deacetylated chitosan is produced in low-concentration alkali and high-pressure conditions under 0.11–0.12 MPa for 120 min. Secondly, microwave deacetylation showed that a degree of deacetylation of 95.19% was achieved after irradiating chitin at 60 meshes with 50% NaOH solution in a microwave for 10 min at 1400-W power. To find these results, the authors used different formulas to calculate DD by FTIRM, but the most used and reliable formula is that which calculates DD of chitosan by the report of absorbance of amide at 1655 cm−1 that measures the acetyl group and absorbance at 3430 cm−1 relating to the hydroxyl group

Characterization and Treatment of Real Wastewater from an Electroplating Company by Raw Chitin

The objective of this chapter is to study of the heavy metal removal in real waste water. The use of the raw chitin shows itself of big potential for the treatment of the liquid discharges of the studied unity. It showed itself capable to treating heavy metal loads superior to 200 mg/l by presenting percentage removal between 90 and 97%, as in the case of Cu2+. After the study performed on the global discharge, we were interested in the local treatment that rinses out plating baths, and this is the aim to optimize the treatment process and develop a project of treatment plant, recycling in situ based on the adsorption technique on raw chitin. Examination of the results allowed us to save significant percentages of sewage treated for metals mainly copper. Raw chitin showed a high affinity toward heavy metals in rinsing water supply. According to this study, the design of a treatment facility of this type of release must include a waste water treatment by adsorption on chitin. The valuation of the raw chitin is situated in this context as an economically adsorbing material, which can be an interest at the level of the recovery of heavy metals in waste water

Chitin/Chitosan’s Bio-Fertilizer: Usage in Vegetative Growth of Wheat and Potato Crops

This chapter consists of valuing the chitosan to create bio-fertilizers as fertilizers without going through the composting process because of their richness in the nutrient base elements of plants: nitrogen and phosphorus. Physicochemical analyses of the chitosan focused on pH, dry matter, organic matter, nitrogen, phosphorus and potassium as well as IR and XRD. The samples thus prepared were monitored for 15 days. PH, temperature and conductivity were monitored daily. According to the physicochemical analyses of waste (nitrogen, phosphorus and potassium) and the nutritional needs of our selected crop (soft wheat, Arrehane variety which are 90-90-50 U/ha), several doses are then determined for the purpose of the optimal formula after their application on the crop. An application of bio-fertilizer on the potato was also undertaken. Follow-ups were carried out during this study, such as the monitoring of the vegetative growth of wheat and the mineralization of the soil via its physicochemical analyses. The results show that our bio-fertilizer is rich in nitrogen with 4.98% and phosphorus with 1.42% and mineralizes quickly on the ground while leaving the soft wheat to absorb its nutrients effectively and improving its growth properties, then giving good yields

Sustainable Treatment of Heavy Metals by Adsorption on Raw Chitin/Chitosan

The objective of this chapter was to treat metal pollution of wastewater rich in Pb2+, Cd2+, Cu2+, and Zn2+ ions by adsorption tests on the raw chitin/chitosan. Different origin namely shrimp (Ccre), crab (Ccra) and lobster (Clan). Raw shrimp chitin had a strong affinity for Pb2+ and Cd2+. The adsorption capacity of zinc on the crabs chitin is twice as great as that on the shrimp chitin. The kinetic study showed that more than 50% of these ions are adsorbed before equilibrium is reached (20 minutes). The adsorption kinetics also showed that the hardness of the shells has a negative effect on the kinetics of the adsorption process. Indeed, the adsorption of Pb2+ on the raw chitin shrimp requires only 30 minutes, while on the raw chitin lobster; the equilibrium time is 60 minutes. To ensure a sustainable treatment, sludge generated by adsorption of heavy metals was incinerated at high temperature. Incineration has led to calcite phases, which do not represent any toxicity on the environment and it can be recycled in the industry of solid materials (ceramics, cement, etc.). However, the regeneration of sludge by the acid changes the structure of the material and gives new adsorbent supports

Study of the Thermal Behavior of Almond Shells and Acorn Cups for Production of Fuel Briquettes

Because of the importance of his field, its neutrality in terms of pollution, biomass sector is an attractive way for the promotion of renewable energies, the fight against deforestation and the protection of our environment. In Morocco, almond shells and acorn cups  are still rejected as a  solid waste, while they can be a source of renewable energy and provide a continuous supply of solid liquid and gas fuels, through a thermochemical conversion. The conversion of acorn cups and almond shells to energy by thermochemical conversion processes requires a fundamental understanding of their thermal properties. The purpose of this research is to investigate the thermal behavior of these wastes, its energy recovery by the production of fuel briquettes from roasted fine and to study combustion behavior of these briquettes. The results of thermogravimetry (TGA), derivate thermogravimetry (DTG) and differential thermal (DTA) analysis allowed us to determine the stages of thermal decomposition of acorns cups and almond shells and associated phenomena. Characterization of briquettes showed us that the particle size and residence time during roasting are the determinants factors of their quality. Keywords: Renewable energy, fuel briquettes, almond shells, acorn cups

Study of the Paranitrophenol Adsorption on the Commercial Bentonite

This work focuses on the study of the behavior of commercial yellow bentonite (BTJ) vis-a-vis paranitrophenol (PNP). Before beginning the study of adsorption, we realized the physiquo-chemical characterization of clay by FTIR, BET and XRD technical. The surface area of the bentonite is calculated by BET 35 m2/g. The adsorption of para-nitrophenol is carried out at room temperature and at a controlled pH. The kinetic study showed that the equilibrium time is 5h. The kinetic model was a pseudo second order. Adsorption isotherm was the Langmuir model. The adsorption capacity was about 0.37 mg / g. Keywords: Yelow bentonite, paranitorphénol, adsorption, optimisation

Evaluation of the Adsorption Kinetics and Equilibrium for the Potential Removal of Phenol Using a New Biosorbent

The adsorption isotherm of phenol on the eggshell (ES) and on the eggshell membrane ( ESM) was performed, it revealed the eggshell biosorbents could uptake the phenol of more than 50 mg/g in aqueous medium, which was attributed to their pore properties. A comparison of kinetic models applied to the adsorption of phenol onto ES was evaluated for the first order and the second order kinetic model.The experimental data fitted very well the second order kinetic model. In the isotherm studies, the Langmuir and Freundlich isotherm models were applied. The results indicate that Langmuir equation is well solution at no pH control. Physical characteristics of ES and ESM such as presence of functional groups were verified. The Fourier transform Infra-red (FTIR) spectra proved the presence of functional groups such as hydroxyl carbonyl groups in ES and in ESM. The results indicate that ES could be fruitfully employed as a natural and Eco-friendly adsorbent material for the removal of residual phenol from effluents. Keywords: phenol, eggshell, adsorption, waste water

Pyrolysis investigation of food wastes by TG-MS-DSC technique

International audienc

Physicochemical Characterization of Regional Clay: Application to Phenol Adsorption

Phenol is one of the most toxic pollutants found in industrial waste. This work focuses on the removal of phenol using clay from the Sale region. Adsorbent was characterized by X-ray fluorescence spectroscopy, X-ray diffraction, infrared spectroscopy, and scanning electron microscopy. The chemical analysis of this clay shows that the percentage of silicon and aluminium is quite high, and the percentage of calcium and iron is relatively high, so this material is rich in muscovite, quartz, and calcite. In addition to the presence of titanium dioxide (TiO2), which can give it a property of degradation of organic compounds under ultraviolet light, the pHPZC zero point of our material is 7.4. The results showed that the adsorption of phenol was well fitted by the pseudo-second-order kinetic model and the Langmuir and Freundlich isotherms and that the best retention is obtained at a pH between 3 and 8

Assessment of Untreated Coffee Wastes for the Removal of Chromium (VI) from Aqueous Medium

Industrial discharges loaded with heavy metals present several problems for aquatic ecosystems and human health. In this context, the present study aims to evaluate the potential of raw spent coffee grounds to remove chromium from an aqueous medium. A structural and textural study of coffee grounds was carried out by FTIR, XRD, and TGA analysis. The optimum conditions for the removal of Cr(VI), for a solution with an initial concentration of 100 mg/l, were adsorbent dose 2.5 g/l, pH 4.0, and contact time 90 min. The adsorption equilibrium results show that the Langmuir isotherm best describes the process with an adsorption capacity of 42.9 mg/g and that the adsorption kinetics follows the pseudosecond-order model. The calculated thermodynamic parameters showed that the adsorption is exothermic and spontaneous. The activation energy value (Ea) indicated that the retention is physisorptive in nature. The regeneration of the adsorbent was carried out by three eluents, among which HCl was the best. Finally, a brief cost estimation showed the great potential of coffee grounds as a low-cost adsorbent