Sulfydryl cellulose type straw adsorbent and preparation method thereof as well as recycling of noble metal silver

Abstract

The invention discloses a sulfydryl cellulose type straw adsorbent. A preparation method comprises the following steps: (1) taking straws and washing; drying at 50 DEG C; adding concentrated sulfuric acid and heating; filtering after stirring; washing to be neutral; filtering again and drying at 60 DEG C for 24 hours to obtain a product A; putting ammonia water and epoxy chloropropane into a reaction container I and reacting at 60 DEG C for 4 hours; adding the product A into the reaction container I and adding NaOH; reacting at 110 DEG C for 8 hours; after the reaction, filtering and washing the product to be neutral; drying at 55 DEG C to obtain a product B; and (2) dissolving thiosemicarbazide into a reaction container II and adding the product B and glutaraldehyde; reacting at 90 DEG C for 5 hours; filtering and washing; and drying at 55 DEG C to obtain a target product. The preparation method is simple, has no pollution and has low cost; the prepared straw adsorbent has high separation and enriching efficiency and trace silver can be separated and enriched from a high-concentration copper-nickel solution; and the preparation method has no energy consumption, is energy-saving and environmentally friendly, has a wide applicable range, and has actual applicability.

Description

technical field [0001] The invention belongs to the technical field of preparation of green adsorbents and extraction of precious metals, and in particular relates to the preparation of a mercaptocellulose-based straw adsorbent and the recovery of precious metal silver. Background technique [0002] Precious metals include 8 elements including gold, silver, platinum, palladium, nails, rhodium, osmium and iridium. Due to their special properties, they are widely used in aerospace, electronics and petrochemical industries. The content of silver in the earth's crust is very small, accounting for only 1×10 -5 %, elemental natural silver exists in nature, but it is mainly produced in the form of compounds. Pure silver is silvery white, with a melting point of 960.8°C, a boiling point of 2210°C, and a density of 10.49 g / cm 3 . Silver is a face-centered cubic lattice with good plasticity and ductility second only to gold, but when it contains a small amount of arsenic, antimony,...

AI Technical Summary

Problems solved by technology

[0003] The separation methods of precious metals mainly include precipitation method, extraction method, ion exchange method, electrolysis method and selective volatilization method, etc. The most prominent shortcomings of these methods are that when treating low-concentration metal wastewater, the operation is cumbersome, the operation cost is high, and the energy consumption is large. , and easily cause secondary pollution

Before the 1970s, the classic refining process based on selective precipitation was used to separate and purify precious metals. The process was long, the cycle was long, the plant area was large, the operation was complicated, and the direct recovery rate was low. Some precious metals were stranded in the production process. Economic benefits are affected

[0004] At the same time, the straw waste generated every year in our country is not only brought great pollution to the environment but also causes a waste of resources through burning. If these wastes can be effectively used, it will not only reduce environmental pollution but also alleviate the energy crisis.

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