Graphene oxide for heavy metal pollution control

Heavy metals generally refer to more than 60 elements with a density of more than 4 or 45 elements with a density of more than 5. However, because the toxicity of different heavy metals in water and soil is very different, in the field of environmental science, people usually pay attention to vanadium, chromium and nickel. , cobalt, copper, zinc, cadmium, tin, mercury, lead and other metal ions. Heavy metal ions can accumulate in the human body and lead to poisoning, cancer and damage to the nervous system, so it is particularly important to do a good job of heavy metal pollution control.

Graphene oxide  is a carbon nano material prepared from natural graphite with a structure similar to carbon nanotubes. Compared with the adsorption capacity of activated carbon, carbon nanotubes and graphene materials for low-concentration lead-containing wastewater, the adsorption capacity of graphene oxide for lead is as high as 800 mg/g, which is much higher than that of activated carbon, which is 60 to 120 mg/g. It has extremely strong regeneration capacity, and the adsorption capacity drops only 5 to 10% after repeated adsorption/elution cycles.

Why does graphene oxide have such a strong heavy metal adsorption capacity? There are two reasons: one is that graphene oxide is a two-dimensional nano material with a thickness of one atomic layer, and its specific surface area can theoretically reach 2600 square meters/g, which is the largest among all carbon nano materials; During the preparation process, a large number of active groups such as carboxyl group, carbonyl group, hydroxyl group, epoxy group, etc. are formed on its surface. Therefore, graphene oxide has the most basic elements required for an excellent adsorbent: a sufficiently large specific surface area and a sufficiently high density of surface functional groups.

The use of graphene oxide material can reduce the discharge concentration of lead-containing wastewater in the lead-acid battery industry from the current 100-1000ppb to 1-10ppb, increase the lead recovery rate to 95%-99%, and reduce the total environmental discharge of lead by 90% compared with the existing technology. %. The achievement can be effectively extended to other heavy metal pollution systems such as cadmium, nickel, arsenic, copper, chromium, and radioactive elements, and has considerable economic and social benefits. https://www.hwnanomaterial.com/

Heat dissipation application of graphite powder in LED lamps

The features of graphite powder are soft, dark gray; oily feel that can contaminate the paper. In the isolated oxygen conditions, the melting point above 3000 ℃, is one of the most resistant minerals. At room temperature, the chemical properties of graphite powder are relatively stable, insoluble in water, dilute acid, dilute alkali and organic solvents; different high temperature reaction with oxygen to produce carbon dioxide or carbon monoxide. It only oxidizes with fluorine and simple carbon in the halogen. Graphite powder is easier to acid oxidation. Besides, it can also react with many metals to form metal carbide, which can be smelted at high temperature.
Graphite powder is the necessary raw materials for industrial production and application. The application of graphite powder has begun to move to the more high-end, which has launched a variety of applications, such as in electronics, new energy, high-end manufacturing, medical and other fields. LED lamps is the environmental protection and energy saving lamps recent years that LED lights cooling is the need to solve the problem of graphite powder.
LED lamps and lanterns of the poor heat can lead to damage to power, light failure accelerated, shortened life and other issues, LED lighting system performance is always the top priority, metal materials in the application of LED cooling difficult to process, energy consumption, density is too large, conductive, easy to deformation and difficult to recover waste and many other issues, and graphite powder material will not be such a problem, graphite powder plasticity is good, easy processing, and has excellent high temperature, thermal conductivity and other properties. Graphite powder can be processed into the graphite heat sink, the heat emitted by the lamp will be absorbed through the graphite heat sink, and even to the surrounding heat, graphite powder and plastic can also be made into a heat sink, cooling the cooling cup and cooling shell and so on.
There are many cooling performance in the application of LED lights, including LED chip packaging components, LED optical lens, light scattering components, efficient cooling components, light reflection and light diffusion board. Graphite powder of high-end products plays an important role in the solar transparent electrode, thermal materials and touch screen and other fields.

Related reading:graphite nanoparticles  graphite nano powders