The Egyptian black sands contain several economic minerals, especially ilmenite. Monazite can reach concentrations up to 0.6 wt.%. The majority of monazite grains have light to deep canary and lemon yellow colors, whereas enigmatic monazite grains have brown, red, resinous, yellow and colorless to pinkish colors. The behavior of monazite with the electrostatic field setting of the roll-type electrostatic separator was studied for the different variables of the separator. Most of the monazite grains are reversible negative and are attracted towards the positively charged static electrode. Using wet gravity concentration, both low and high intensity magnetic separation, and electrostatic separation techniques, a high grade concentrate assaying 97 wt. % monazite with a recovery of 76.8% can be obtained.The Egyptian beach monazite contains high concentrations of Ce, La and Nd in addition to minor amounts of Y, Pr, Sm, Gd, Dy and Eu. It is particularly rich in the lighter rare earth elements (cerium subgroup). By a new method of ion exchange technique after chemically dissolving the mineral with sulfuric acid, both of REEs, Th and U, could be individually separated. The efficiency of the separation has been tested with sulfuric acid concentration at 2M H 2SO4 where the thorium and uranium could be obtained with a cation exchange synthetic resin column, while rare earth metal ions are adsorbed and then individually separated. A highly pure thorium product could be obtained by oxalate precipitation followed by uranium precipitation as diuranate using NaOH.

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Egyptian beach ilmenite occurs in a relatively high content in the naturally highly concentrated superficial black sand deposits at specific beach zones in the northern parts of the Nile Delta at Rosetta. Microscopic study shows that the ilmenite occurs as fresh homogeneous black or heterogeneous multicoloured altered grains and exhibits three types (homogeneous, exsolved and altered) of ilmenite varieties. XRD data of ilmenite indicates their association with minor hematite and quartz, whereas leucoxene shows its association with Nb‐rutile, pseudorutile and hematite. Grain size distribution suggests a very fine sand size of >89% and 80% and a fine sand size of 10.5% and 18.3% for fresh and altered ilmenites, respectively. The density of fresh, altered ilmenite and leucoxene concentrates varies from 2.70, 2.50 to 2.40 ton/m3, suggesting a gradual decrease from high grade fresh to leucoxene and consistent with variation in magnetic susceptibility as a consequence of the leaching of iron. Mass magnetic susceptibility reveals 97.6% of ilmenite and 92% of the altered form are obtained at 0.20 and 0.48 ampere. Fresh ilmenite exhibits variable TiO2 (47.18%) and Fe2O3T (46.10%) with minor MnO, MgO and Cr2O3 (1.22, 1.10 and 0.51%). The altered ilmenite is higher in TiO2 (76.16%) and SiO2 (4.68%) and lower in Fe2O3T (14.45%), MnO, MgO and Cr2O3 (0.39, 0.52 and 0.11%) compared with the fresh form. Three concentrates of ilmenites (G1, G2 and G3) were prepared from crude ore using a Reading cross belt magnetic separator under different conditions, revealing a gradual increase of TiO2, SiO2, Al2O3 and CaO accompanied by a decrease of Fe2O3T, MgO and Cr2O3 with repetition of the separation processes. Several ore dressing techniques were carried out to upgrade the ilmenite concentrate.

The Egyptian black sands contain several economic minerals, such as ilmenite, magnetite, garnet, zircon, rutile and monazite. During the concentration and separation of a high-grade rutile concentrate a bulk magnetic fraction is obtained. This fraction is composed mainly of opaques, titanhematite, ilmenite-titanhematite exsolved intergrown grains, magnetic leucoxene in addition to chromite, and magnetic rutile. The magnetic rutile occupies 6 wt.% of the bulk magnetic fraction or approx. 4 wt.% of the original rutile content in the raw sands. Most of magnetic rutile crystals are contaminated with opaque inclusions, staining-coating and/or composite locked grains. This magnetic rutile has a magnetic range from strongly paramagnetic to very weak paramagnetic. Electron microprobe analysis for twenty-three magnetic rutile grains identified mineral components of rutile, titanhematite, pseudorutile, leached pseudorutile and ilmenite in decreasing order of abundance. Some other inclusions are also detected in the different magnetic rutile grains. They are most probably garnet, silica, amphibole, ilmenite, feldspar, mica and zircon. The presence of these inclusions reflect the derivation of magnetic rutile of various crystalline igneous and metamorphic rocks. The magnetic susceptibility of magnetic rutile depends on the associated mineral components and their relative volumes in comparison to the rutile mineral component. Magnetic susceptibility of magnetic rutile is also related to both type and size of the associated mineral inclusions. The average chemical composition of the magnetic rutile is 66.34 wt.% TiO 2, 21.71 wt.% Fe2O3, 6.39 wt.% SiO2, 1.80 wt.% Al2O3, 1.19 wt.% CaO and 0.10 wt.% Cr2O3. Thus, the contamination of magnetic rutile in the non-magnetic rutile concentrate would decrease the market value of the rutile concentrate. Alternatively these magnetic rutile grains are recommended to be blended with magnetic leucoxene or some types of ilmenite concentrate to improve the overall marketable specifications especially for both of Ti, Fe and Cr contents.

The potential heavy minerals content of the black-sand resources in Rosetta is investigated using optical microscopy, X-ray diffraction, scanning electron microscope, electron-microprobe analysis and inductively coupled plasma-mass spectrometry. The separation of individual minerals was done by wet-gravity and applying magnetic and electric approaches. The composition and morphology of the studied heavy minerals such as zircon, monazite, garnet, magnetite, ilmenite and rutile are compared with their equivalents in the Nile sources to elucidate their fate during the long transportation. Shukri's samples of the Nile sediments that were collected and studied during the mid-twentieth Century are adopted for this comparison. Generally, mineral grains turn to be polished and free of contamination upon long transportation while others are entirely lost before reaching the influx. Even the ultrastable minerals such as zircon and monazite experienced some changes in their chemical composition during transportation. The REE geochemistry suggests that the coarse grained zircon was possibly derived from highly fractionated and altered pegmatitic rocks of White Nile proximity while the fine grained variety was derived from the Ethiopian hinterlands. Two monazite varieties are distinguished, namely; Ce-monazite and Th-monazite, however, the extreme Eu deficiency (ΔEu= <0.1) is used to assign derivation from highly fractionated felsic sources. Garnet belongs essentially to alamandine variety is derived from metamorphic rocks such as the prevailing twomica schist of White Nile provenance. The opaque minerals; magnetite, ilmenite and rutile have nearly flat chondrite-normalized REE patterns but with slight enrichment in LREE. These minerals are good indicators of the volcanic source of the Ethiopian plateau. Few gold grains have been detected in the high grade cassiterite concentrate with average concentration of 7780 ppb Au. The 70 A.A. El-Kammar et al. radioactivity in the studied black sands is essentially attributed to both uranium and thorium series mostly related to monazite, zircon, garnet and ilmenite.

Geomorphologically, the study area comprises three geomorphic units, the foreshore zone, the backshore flat and coastal sebkhas. El-Sahel (coastal) drain runs parallel to the shoreline. The coastal plain of study area is divided to northern and southern sectors; each sector covers an area of about 10Km2. The northern sector is characterized by relatively highly concentrated black sand especially the near shore area due to marine erosion and the southern sector is characterized by diluted homogenous sediments compared with the northern one.Along the shoreline of the study area, erosion and accretion phenomena are indicated by alternations of highly concentrated and low concentrated sediments, distribution of flaky, discoidal, spherical stones and mud balls. The north-western part of the northern coastal plain sector of the study area is characterized by the highly concentrated black sands extends from the fifth groin eastward about 2.5 Km. These deposits are affected greatly by a wave cut along the shore line. Rate of shoreline retreat along Abu-Khashabah beach in front of El-Matlaa Medak (road) was 43.66 m/y in the time interval between 2003 and 2012.The coastal plain of study area was covered by a total 561 collected samples at one meter depth from the surface were collected within a grid pattern 200m×200m nearly parallel and perpendicular to the shoreline. The northern sector of coastal plain area is covered by 255 samples, whereas the southern sector covered by 306 samples. Naturally highly concentrated black sands are deposited in a thin mantle near and parallel to the shoreline of the northern coastal plain sector. The highly concentrated black sands were scraped from the mantle to a depth of about 30 cm.Separation of economic heavy minerals Concentrates using physical ore dressing technique is considered closer to reality; cheap and safe method than the heavy fluid technique.The average content (Av. cont.) and reserve tonnage for each economic mineral in the studied sectors are: magnetite has an average content 11.61% with a reserve 296055 ton, ilmenite has an average content 33.74% with a reserve 860370 ton, garnet has an average content 2.88% with a reserve 73440 ton, leucoxene has an average content 2.58% with a reserve 65790 ton, zircon has an average content 4.11% with a reserve 104805 ton, rutile has an average content 1.26% with a reserve 3210 ton and monazite has an average content 0.05% with a reserve 1275 ton with a total average of economic minerals 56.23% and reserve of 1433865 tons.

Exposure to hydroquinone (HQ) can cause various health hazards and negative impacts on the environment. Therefore, we developed an efficient electrochemical sensor to detect and quantify HQ based on palladium nanoparticles deposited in a porous silicon-polypyrrole-carbon black nanocomposite (Pd@PSi−PPy−C)-fabricated glassy carbon electrode. The structural and morphological characteristics of the newly fabricated Pd@PSi−PPy−C nanocomposite were investigated utilizing FESEM, TEM, EDS, XPS, XRD, and FTIR spectroscopy. The exceptionally higher sensitivity of 3.0156 μAμM−1 cm−2 and a low limit of detection (LOD) of 0.074 μM were achieved for this innovative electrochemical HQ sensor. Applying this novel modified electrode, we could detect wide-ranging HQ (1–450 μM) in neutral pH media. This newly fabricated HQ sensor showed satisfactory outcomes during the real sample investigations. During the analytical investigation, the Pd@PSi−PPy−C/GCE sensor demonstrated excellent reproducibility, repeatability, and stability. Hence, this work can be an effective method in developing a sensitive electrochemical sensor to detect harmful phenol derivatives for the green environment.