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1.
ACS Omega ; 8(45): 42622-42631, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-38024686

RESUMO

In this work, we address two concerns at once: waste reduction and the development of a lead removal adsorbent. The potential of Lupinus albus seed hull (LSH) powder as an efficient, innovative, and economical adsorbent for Pb(II) absorption was examined in this study. Fourier transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, and scanning electron microscopy investigations were used to determine the structural and morphological properties of the LSH adsorbent. The adsorption process was studied in batch mode with multiple process variables (adsorbent dosage of 4.0-20 g/L; solution pH of 1.5-5.5; contact time of 15-70 min). By fitting the equilibrium data to the Langmuir isotherm model, the maximum adsorption capacity of Pb(II) was 357.14 mg/g at optimized pH (5.5), LSH dose (0.4 g), and interaction time (60 min) with starting Pb(II) concentration of 50 mg L-1. As for the reaction kinetics, the pseudo-second-order model was shown to be a convenient match. LSH can be reused after four desorption/adsorption cycles and has a high potential for eliminating Pb(II) from wastewater.

2.
ACS Omega ; 8(28): 25378-25384, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37483228

RESUMO

Drugs that are illegal have long been a part of Egyptian society. The most widely misused form of narcotic is marijuana, also known as "bango", and other cannabis-related products like "hashish". The chemical profile of some available "hashish" in the local Egyptian illegal market and its possible country of origin are investigated using a gas chromatography-mass spectrometry technique in conjunction with a thermal separation probe (TSP/GC/MS). The TSP/GC/MS method reveals the presence of 23 different terpenes, of which caryophylla-4(12),8(13)-dien-5α-ol, isoaromadendrene epoxide, caryophyllene, and alloaromadendrene oxide-(1) are detected in high relative proportions. Ten cannabinoid components are also detected. These are cannabiorcochromene (CBC-C1), tetrahydrocannabivarin (THCV), delta-8-tetrahydrocannabinol (delta-8-THC), exo-THC, cannabichromene, cannabidiol (CBD), cannabielsoin (CBE), dronabinol (delta-9-THC), cannabigerol (CBG), and cannabinol (CBN). Phenotypic index (THC % + CBN %)/CBD %) is measured for the test samples to identify both the nature of the samples (fiber- or drug-type cannabis) and the country of origin.

3.
J Hazard Mater ; 162(2-3): 994-9, 2009 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-18635316

RESUMO

Removal of some reactive dyes (RY-145, RR-194 and RB-B) from textile wastewater effluents using Sorel's cement is described. Parameters affecting dye uptake including contact time, reagent dosage and pH are examined and optimized. Dye adsorption equilibrium data are fitted well to the Langmiur isotherm rather than Freundlish isotherm. The adsorption isotherm indicates that the adsorption capacities are 107.67, 120.89 and 103.14 mg dye per gram of Sorel's cement for RY-145, RR-194 and RB-B reactive dyes, respectively. The adsorption isotherms, including Langmuir constant (Q degrees and b) and Frendlich constant (K(F) and n), for the dyes decrease with the increase of temperature. The values of enthalpy change (DeltaH) for RY-145, RR-194 and RB-B dyes are -146.96, -49.23 and -264.86 kJ mol(-1), respectively, indicating that the removal process is exothermic. The sorption of the dyes is enhanced by increasing the pH, reaching a maximum at pH 6-11. Experimental runs conducted to measure the chemical oxygen demand (COD) of textile wastewater loaded with reactive dyes, reveal approximately 96% removal of the COD contents within 30 min under optimized conditions.


Assuntos
Corantes/isolamento & purificação , Materiais de Construção , Resíduos Industriais , Indústria Têxtil , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Concentração de Íons de Hidrogênio , Termodinâmica
4.
J Hazard Mater ; 154(1-3): 992-7, 2008 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-18093728

RESUMO

Camel bone charcoal is used as an adsorbent for the removal of Hg(II) from wastewater effluents. The equilibrium data are fitted to Langmiur isotherm rather than linear and Freundlich isotherms. The adsorption capacity Qo is 28.24 mg of Hg(II)/g of the adsorbent. The optimum removal conditions are pH 2, contact time 30 min and temperature 25 degrees C. A comparison of the adsorption capacity (Qo) of camel bone charcoal with different adsorbents previously used for Hg(II) removal from wastewater effluents reveals its remarkable efficiency over many other treated and untreated natural and synthetic adsorbents. X-ray fluorescence and infrared spectrometry of camel bone charcoal after contact with mercury solutions confirm surface adsorption of Hg(II) ions. Electron microscopy reveals the formation of a spongy like structure on the adsorbent surface due to Hg(II) adsorption. Quantitative removal of mercury from hazardous effluents is demonstrated.


Assuntos
Osso e Ossos , Carvão Vegetal/química , Mercúrio/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Adsorção , Animais , Camelus , Concentração de Íons de Hidrogênio
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