CN104923280A - Compound solid acid catalyst with high nitrate conversion rate and preparation method thereof - Google Patents

Abstract

The invention discloses a compound solid acid catalyst with a high nitrate conversion rate. The catalyst is characterized by being prepared from the following raw materials by weight: 40 to 50 parts of gamma-alumina, 7 to 10 parts of attapulgite, 8 to 12 parts of lanthanum oxide, 35 to 40 parts of silica, 10 to 15 parts of aramid fiber, 13 to 18 parts of methacryloxypropyltrimethoxysilane, 0.4 to 0.8 part of phosphoric acid, 1 to 3 parts of palladium nitrate and a proper amount of water. According to the invention, since an aqueous palladium nitrate solution acidizes the surface of the attapulgite and then is uniformly loaded on the silica, a stable covalent structure of Mg-O-Si and Ca-O-Si is formed, so the structure of SiO2 is not destroyed in loading process, and a generated compound has large specific surface area; meanwhile, the added aramid fiber particles are bonded on the surface of aluminium oxide, so adsorbability and toughness are improved, and characteristics of strong acidity, high conversion rate, recyclability and environmental friendliness are obtained; meanwhile, acid is not added in reaction process, so equipments are prevented from corrosion.

Description

Composite solid-acid catalyst that a kind of nitrate anion conversion ratio is high and preparation method thereof

Technical field

The present invention relates to solid acid catalyst technical field, be specifically related to high composite solid-acid catalyst of a kind of nitrate anion conversion ratio and preparation method thereof.

Background technology

Isosorbide-5-Nitrae-dioxane (Isosorbide-5-Nitrae-dioxane), molecular formula C ₄h ₈o ₂, colourless liquid, slightly fragrance, density 1.0329, refractive index 1.4175, fusing point 11 DEG C, boiling point 101.1 DEG C, with water and many immiscible organic solvents, be the solvent of cellulose acetate, resin, vegetable oil, mineral oil, oil-soluble dyes etc., also for system spray paint, varnish, plasticizer, wetting agent etc.

1 is produced at present in the chemical production processes of reality, 4-dioxane great majority still adopt liquid acid such as the concentrated sulfuric acid as catalyst, although have inexpensive, reaction temperature is low, conversion ratio is high, reactivity advantages of higher, but there is, raffinate serious to equipment corrosion and waste water environmental pollution is serious, operating condition is harsh, product post processing is more difficult, accessory substance is many, poor selectivity and be difficult to realize the shortcomings such as continuous seepage in technique, the needs of current environmental protection and economic development can not be met; Though existing fraction enterprise adopts solid acid catalyst aluminium oxide or molecular sieve etc. in prior art, exist be easy to solution-off, less stable, life-span compared with short, easy in inactivation, the defect such as acid strength distribution is wide, aperture is little, the surface nature of easy carbon distribution, catalyst is complicated.If prepare nontoxic composite solid-acid catalyst, then above-mentioned problems just can be resolved, and replace liquid acid as catalyst to be also the important channel realizing environmental friendly catalysis new technology with solid acid.

Summary of the invention

Object of the present invention is just to provide high composite solid-acid catalyst of a kind of nitrate anion conversion ratio and preparation method thereof, to overcome the deficiencies in the prior art.

The object of the present invention is achieved like this:

The composite solid-acid catalyst that a kind of nitrate anion conversion ratio is high, it is characterized in that, be made up of the raw material of following weight portion: gama-alumina 40-50, attapulgite 7-10, lanthana 8-12, silica 35-40, aramid fiber 10-15, methacryloxypropyl trimethoxy silane 13-18, phosphoric acid 0.4-0.8, palladium nitrate 1-3, suitable quantity of water.

The preparation method of the composite solid-acid catalyst that described a kind of nitrate anion conversion ratio is high, is characterized in that comprising the following steps:

(1) palladium nitrate is added water to be stirred to dissolve completely, add phosphoric acid, attapulgite soaks 10-12 hour, grinding pulping, add silica and flood absorption 2-4 hour under high velocity agitation, be placed in stainless steel cauldron, in 110 DEG C of hydrothermal treatment consists 6h after sealing, suction filtration, washing, dry at 80 DEG C, grind for subsequent use;

(2) aramid fiber is crushed to 200-300 order, adds gama-alumina, methacryloxypropyl trimethoxy silane ultrasonic wave is dried for dispersion grinding 3-5 hour;

(3) by step (1), the mixing of (2) material, add other residual components and stir 30-50 minute, microwave drying grinding discharging in 3 hours at leaving standstill 1-5 hour, 160-180 DEG C.

The present invention has following beneficial effect: the present invention adopts palladium nitrate aqueous solution to uniform load after attapulgite's surface acidification on silica, and form the covalent structure of stable Mg-O-Si and Ca-O-Si, loading process does not destroy SiO ₂structure and generate compound specific area larger, add aramid fiber particles stick at alumina surface simultaneously, improve adsorptivity and toughness, the composite solid-acid catalyst utilizing the present invention to obtain have acid strong, conversion ratio is high, can be recycled and eco-friendly feature, solve the common fault of the easy carbon distribution of common metal oxides solid acid catalyst easy in inactivation, and in course of reaction, there is no adding of acid, avoid equipment corrosion, there is environment friendly.

Detailed description of the invention

The composite solid-acid catalyst that described a kind of nitrate anion conversion ratio is high, it is characterized in that, be made up of the raw material of following weight portion: gama-alumina 48, attapulgite 9, lanthana 11, silica 36, aramid fiber 13, methacryloxypropyl trimethoxy silane 16, phosphoric acid 0.7, palladium nitrate 1, suitable quantity of water.

Preparation method comprises the following steps:

(1) palladium nitrate is added water to be stirred to dissolve completely, add phosphoric acid, attapulgite soaks 10-12 hour, grinding pulping, add silica and flood absorption 2-4 hour under high velocity agitation, be placed in stainless steel cauldron, in 110 DEG C of hydrothermal treatment consists 6h after sealing, suction filtration, washing, dry at 80 DEG C, grind for subsequent use;

(2) aramid fiber is crushed to 200-300 order, adds gama-alumina, methacryloxypropyl trimethoxy silane ultrasonic wave is dried for dispersion grinding 3-5 hour;

(3) by step (1), the mixing of (2) material, add other residual components and stir 30-50 minute, microwave drying grinding discharging in 3 hours at leaving standstill 1-5 hour, 160-180 DEG C.

The technical parameter index of the composite solid-acid catalyst using the present invention to produce is as follows: catalytic production Isosorbide-5-Nitrae-dioxane conversion ratio is 65.2%, selective close to 100%.

Claims (2)

1. the composite solid-acid catalyst that a nitrate anion conversion ratio is high, it is characterized in that, be made up of the raw material of following weight portion: gama-alumina 40-50, attapulgite 7-10, lanthana 8-12, silica 35-40, aramid fiber 10-15, methacryloxypropyl trimethoxy silane 13-18, phosphoric acid 0.4-0.8, palladium nitrate 1-3, suitable quantity of water.

2. the preparation method of the composite solid-acid catalyst that a kind of nitrate anion conversion ratio according to claim 1 is high, is characterized in that comprising the following steps:

(1) palladium nitrate is added water to be stirred to dissolve completely, add phosphoric acid, attapulgite soaks 10-12 hour, grinding pulping, add silica and flood absorption 2-4 hour under high velocity agitation, be placed in stainless steel cauldron, in 110 DEG C of hydrothermal treatment consists 6h after sealing, suction filtration, washing, dry at 80 DEG C, grind for subsequent use;

(2) aramid fiber is crushed to 200-300 order, adds gama-alumina, methacryloxypropyl trimethoxy silane ultrasonic wave is dried for dispersion grinding 3-5 hour;

(3) by step (1), the mixing of (2) material, add other residual components and stir 30-50 minute, microwave drying grinding discharging in 3 hours at leaving standstill 1-5 hour, 160-180 DEG C.