Comprehensive utilization of serpentine

Serpentine mines are generally mined with rich ore bodies. The raw ore can be sold after crushing and screening and reaching certain crushing requirements.

In order to explore the separation way of serpentine and its associated useful minerals, the flotation characteristics of serpentine were also studied. The results show that both sodium oleate and dodecylamine hydrochloride have good collection performance for serpentine. It is speculated that the Mg particles on serpentine surface are the active sites adsorbed by oleate, while amine is adsorbed on serpentine surface in molecular state when flotation is carried out with cationic collector dodecyl amine salt. Sodium silicate has a strong inhibitory effect on serpentine flotation.

② Using serpentine as raw material to produce calcium magnesium phosphate.

At present, domestic enterprises producing calcium magnesium phosphate with serpentine as ingredients mainly include: Guangxi Phosphate Fertilizer Plant, Yunnan Phosphate Fertilizer Plant and Jiangsu Donghai Phosphate Fertilizer Plant.

③ Extracting magnesium oxide from serpentine.

Serpentine is a high magnesium mineral. The idea and technology of extracting magnesium oxide from serpentine was first put forward in Austria. This method is expected to be the third method to produce magnesium oxide besides extracting magnesium and magnesite from seawater, and compared with extracting magnesium from seawater, the magnesium oxide produced by this method does not contain soluble substances such as sodium pyroborate. Magnesium oxide is extracted from serpentine: serpentine invades acid.

(1) Soluble Partial Purification of Spray Calcined Magnesium Oxide Products

(2) purifying and drying the insoluble part of the porous silica product.

In a multi-stage series leaching device, 0 ~1mm serpentine particles are leached in 20% hydrochloric acid at 105℃. The residence time of serpentine particles in hydrochloric acid is 2.5 hours. After purifying the leaching solution to remove impurities such as iron, magnesium oxide products with purity above 99% can be obtained by spray calcination. The leaching residue is porous silica with a pore size of 0-2nm and a specific surface area of150m2/g/g. This leaching residue has been successfully applied to papermaking, brewing and dirt purification.

Using the above process, 380 kg of high-quality magnesium oxide and 250 kg of silicon dioxide can be produced per ton of serpentine on average.

(4) Extracting useful components Australia has extracted high-grade magnesium oxide and porous silica from serpentine. Porous silica can be used for papermaking, wine making and sewage purification. China has also achieved initial results through experiments, and the purity of extracted magnesia and porous silica is above 99.5%. The Institute of Public Pollution Resources of Japan University of Technology has developed a new technology for extracting amorphous silicon dioxide (SiO2 _ 2) from serpentine, that is, crushing serpentine into particles with a diameter of 30μm, making it into light gray powder, demagnetizing to remove the magnetic substances in it, and then pickling with hydrochloric acid or sulfuric acid with a concentration of 10-20% at 100℃ to obtain white amorphous. High-quality carbon black was added to amorphous silicon dioxide and reacted at high temperature (about 2000℃) to produce silicon carbide single crystal fiber and silicon carbide crystal. The hardness of silicon carbide (SiC) is second only to that of diamond, and its melting point is as high as 2700℃, which can be used to make grinding wheels and high-grade refractories. Silicon carbide single crystal can be used as a material for making high-grade radio components. The English name of Serpentinejade is Serpentine Jade, and the craft name is Xiuyu. In essence, it refers to the fine fibrous serpentine mineral aggregate with serpentine mineral content above 85%, bright color, compactness and smoothness.

The source of jade is quite extensive. In order to distinguish it from nephrite, the name of jade is generally a place name plus the word "jade". Jade in a narrow sense refers to serpentine jade produced in Xiuyan County, Liaoning Province, so jade is also called "xiuyan jade". Jade in a broad sense includes Kunlun jade and Tori jade (also known as snake green jade) produced in Xinjiang. Jiuquan Xiuyu produced in Gansu; Qilian jade (also known as Jiuquan jade) and Dulanyu (also known as Zhuyeqing jade) produced in Qinghai; Xiuyu in Taiwan Province Province is produced in Taiwan Province Province; Nanyu (also known as Xinyiyu) produced in Guangdong; Ji 'an Xiuyu (also known as Anshan Rock) produced in Jilin; Lu Chuan Xiu Yu produced in Guangxi; Yunnan jade produced in Yunnan; Huili Xiuyu produced in Sichuan; Penglai Xiuyu and Junan Xiuyu produced in Shandong; Beijing jade (also called Beijing topaz) is produced in the Ming Tombs in Beijing. Xiuyan jade is the best serpentine jade in China, with bright color, delicate texture and crystal clear. The foreign varieties of serpentine jade are Han Guoyu (also known as Korean jade), which belongs to high-quality serpentine jade; Bao Wenyu of New Zealand; William jadeite made in America and Tiger Eye Stone made in California; Recobalite in Mexico, etc.

The difference between serpentine jade and similar jade. Similar jadeites are prehnite and hydrogrossular. Their differences are mainly identified from hardness, density, refractive index, magnifying observation and so on. Prehnite: It is composed of fibrous prehnite aggregate with hardness of 6-6.5, refractive index of 1.63 and density of 2.88g/cm3. It is anisotropic, foamed in hydrochloric acid and has radial fiber structure. Hydrogrossular: hardness 7, refractive index 1.72, density 3. 15-3.55g/cm3, isotropic body, granular structure, and many small black spots. In addition, serpentine jade is easily confused with jadeite and nephrite, but its hardness is less than jadeite and nephrite. Emerald has obvious waxy luster, while jadeite and nephrite are both glassy luster. It is easy to distinguish them by testing hardness and observing gloss.

Evaluation and purchase of serpentine jade. The quality evaluation of serpentine jade is carried out from the aspects of color, transparency, texture and fragmentation. First, the brighter the color, the better, and the more uniform it is. Second, the higher the transparency, the better; Third, the finer the texture, the better; Fourth, the bigger the better. Serpentine jade has many producing areas, many varieties, large output and low hardness. It is a low-grade jade material, far less precious than jadeite and nephrite. The evaluation factors of serpentine jade are also the basis for purchasing jade products, and attention should be paid to the fineness of workmanship in its value.

Jade is an early jade material developed and applied by China ancestors, with a history of 7000 years. Jade shovels and knives made of jade are very useful at Hemudu Cultural Site in Yuyao City, Yufu, Zhejiang Province. Two pieces of gold and jade clothes unearthed from the Han tomb in Mancheng, Hebei Province, caused a sensation all over the world. They are made of 2,498 pieces and 2 160 pieces of jade, most of which are carved from jade. From ancient times to the present, people in China regard Xiuyu products as ritual vessels, ceremonial vessels, ornaments, tools, household appliances and so on. Xiuyu's modern products are dazzling and widely used. Serpentine jade is a collection of fine fibrous serpentine minerals, which was formed in the process of geological process and reached the jade level. This definition can be distinguished from serpentine and other jade.

The main variety of serpentine jade in China is xiuyan jade, which is called Xiuyu for short. It is a dense block, mainly composed of chrysotile and diorite. Microscopically, it has a fibrous scale crystal structure, and a few have a bundle or scale or fine-grained crystal structure. Besides serpentine and chrysotile, the constituent minerals sometimes contain a small amount of dolomite, magnesite, tremolite and olivine. Xiuyan jade is a kind of nephrite, which was first discovered and utilized. Its texture is delicate and moist, with greasy or waxy luster. Xiuyan jade is also one of the "Four Famous Jade" in China.

The color of xiuyan jade deepens with the increase of Fe2+ content. Almost transparent, translucent to opaque. When the constituent minerals are serpentine, the transparency is high, and when other impurity minerals increase, the transparency becomes low or even opaque. Dark colors have low transparency and light colors have high transparency. It occurs in dolomite marble and is a medium-temperature hydrothermal deposit.