Q. Zinc oxide is found in Rajasthan, What is the effect of this discovery on the economics of India? (46 BPSC/2005)

Q. Zinc oxide is found in Rajasthan, What is the effect of this discovery on the economics of India? (46 BPSC/2005)

Ans:Zinc oxide is an inorganic compound with the formula ZnO. ZnO is a white powder that is insoluble in water, and due to its anti-bacterial, anti-viral, UV-protection properties, it is used as an additive in numerous materials and products including sunscreens, oral care products, vitamins, rubbers, plastics, ceramics, glass, cement, lubricants, paints, ointments, adhesives, sealants, pigments, foods, batteries, ferrites, fire retardants, and first-aid tapes.Although it occurs naturally as the mineral zincite, most zinc oxide is produced synthetically.
The effect on the economics of India:

• Rubber manufacture:
  • Between 50% and 60% of ZnO use is in the rubber industry. ZnO additive also protect rubber from fungi and UV light.
• Ceramic industry:
  • The relatively high heat capacity, thermal conductivity and high temperature stability of ZnO coupled with a comparatively low coefficient of expansion are desirable properties in the production of ceramics.
  • Zinc in small amounts improves the development of glossy and brilliant surfaces. However, in moderate to high amounts, it produces matte and crystalline surfaces.
• Medicine:
  • It has applications as a restorative and prosthodontic in dentistry.
  • The fine particles of the zinc oxide have deodorizing and antibacterial properties and for that reason are added into materials including cotton fabric, rubber, oral care products, and food packaging.
  • Zinc oxide is widely used to treat a variety of skin conditions, including dermatitis, itching due to eczema, diaper rash and acne.
  • It is used in products such as baby powder and barrier creams to treat diaper rashes, calamine cream, anti-dandruff shampoos, and antiseptic ointments.
  • Many sunscreens use nanoparticles of zinc oxide (along with nanoparticles of titanium dioxide) because such small particles do not scatter light and therefore do not appear white.
  • Zinc oxide is used to treat or prevent minor skin irritations such as burns, cuts, and diaper rash.
• Cigarette filters:
  • Zinc oxide is a component of cigarette filters. A filter consisting of charcoal impregnated with zinc oxide and iron oxide removes significant amounts of hydrogen cyanide (HCN) and hydrogen sulfide (H2S) from tobacco smoke without affecting its flavor.
• Food additive:
  • Zinc oxide is added to many food products, including breakfast cereals, as a source of zinc, a necessary nutrient.
• Pigment: Zinc white is used as a pigment in paints
• UV absorber:
  • Micronized and nano-scale zinc oxide and titanium dioxide provide strong protection against UVA and UVB ultraviolet radiation, and are used in sanscreen, and also in UV-blocking sunglasses for use in space and for protection when welding.
• Coatings:
  • Paints containing zinc oxide powder have long been utilized as anticorrosive coatings for metals.
• Corrosion prevention in nuclear reactors:
  • Zinc oxide depleted in 64Zn is used in corrosion prevention in nuclear pressurized water reactors.
• The potential use of ZnO are in laser diodes and light emitting diodes (LEDs) because it has wide direct band gap.
• ZnO is a promising anode material for lithium-ion battery because it is cheap, biocompatible, and environmentally friendly.

Safety concern: Zinc oxide itself is non-toxic; however it is hazardous to inhale zinc oxide fumes, as generated when zinc or zinc alloys are melted and oxidized at high temperature. Exposure to Zinc Oxide flume can cause “metal fume fever” in long term. This is a flu-like illness with symptoms of metallic taste in the mouth, headache, fever and chills, aches, chest tightness and cough.