The invention relates to a process for preparing synthetic calcium fluoride (CaF.sub.2) (min 90% CaF.sub.2 by weight) from fluosilicic acid, comprising the following steps: (a) reacting fluosilicic acid (H.sub.2SiF.sub.6) with ammonium hydroxide or ammonia in a first reactor so as to obtain a first slurry; filtering said first slurry so as to obtain a filtrate containing a solution of ammonium fluoride; (b) precipitating the solution of ammonium fluoride obtained as a filtrate in step (a) with calcium carbonate as a dry form or as a suspension at a concentration ranging from 10 to 80% by weight in a second reactor so as to produce a second slurry containing calcium fluoride and ammonium carbonate; filtering said second slurry so as to obtain a filter cake containing calcium fluoride and a filtrate containing a solution of ammonium carbonate; washing and drying said filter cake so as to obtain calcium fluoride and a filter cake washing containing a solution of ammonium carbonate; wherein a portion of the second slurry ranging from 10 to 70% is recycled to the second reactor (3) so as to enhance calcium fluoride crystallization; (c) evolving the major part of ammonia from the second reactor (3) in step (b) because of the partial decomposition of ammonium carbonate under reactor conditions and then scrubbing and returning said ammonia to the first reactor, and gathering and treating by distillation and condensation both ammonium carbonate solutions obtained as the filtrate and the filter cake washing in step (b) to recover liquid ammonia which is recycled to the first reactor (1).

Methods for electrocatalytic and thermocatalytic conversion of nitrate using PtxRuy/C catalysts are disclosed herein. The methods for electrocatalytic conversion of nitrate to ammonia can include contacting a nitrate containing source with an electrode comprising a PtxRuy/C catalyst while applying a potential sufficient to reduce nitrate to thereby convert nitrate present in the nitrate containing source to ammonia, wherein the PtxRuy/C catalyst comprises a carbon substrate having PtxRUy nanoparticles disposed thereon, and x is about 48 at % to about 90 at %, and y is 1x.

A process for producing ammonia includes the step of contacting nitrogen and water with a catalyst containing permanently polarized hydroxyapatite.

A process for capturing carbon dioxide includes the steps of mixing a hydrogen stream and a feedstock stream to produce a mixed stream, wherein the feedstock stream includes hydrocarbons, reacting the hydrocarbons and the hydrogen in the primary reactor of the hydroprocessing unit to produce a hydroprocessing product stream and a carbon dioxide stream, wherein the hydroprocessing product stream includes light products, wherein the hydroprocessing unit is further configured to produce ammonium bisulfide, collecting the ammonium bisulfide in the water to produce a sour water, processing the sour water in the waste water unit to produce an ammonia stream, a hydrogen sulfide stream, and a stripped water stream, introducing the ammonia stream to a carbon dioxide recovery system, and separating carbon dioxide from the carbon dioxide stream using the ammonia in the ammonia stream to produce a carbon dioxide product.

A reforming device according to the present invention has a compressor, a first heat exchanger, a desulfurization device, a reformer, a raw material gas branching line that extracts a compressed natural gas from a downstream side of the desulfurization device with respect to the flow direction of the natural gas and supplies the natural gas to the reformer, and a flue gas discharging line that discharges a flue gas generated in the reformer, wherein the first heat exchanger is provided in the flue gas discharging line, and the flue gas is used as a heating medium of the compressed natural gas.

An after-treatment system including an exhaust treatment component provided in an exhaust passage, a tank carrying an aqueous reagent, and an electrochemical cell in communication with the tank and configured to receive the aqueous reagent therefrom. The electrochemical cell is configured to convert the aqueous reagent into a first exhaust treatment fluid and a second exhaust treatment fluid. A controller is in communication with the electrochemical cell. The controller is configured to vary amounts and/or composition of each of the first exhaust treatment fluid and the second exhaust treatment fluid produced by the electrochemical cell. An injector is in communication with the electrochemical cell and the exhaust passage, and is configured to receive one of the first exhaust treatment fluid or the second exhaust treatment fluid from the electrochemical cell, and dose the one exhaust treatment fluid into the exhaust passage at a location upstream from the exhaust treatment component.

Methods for producing renewable ammonia are disclosed. Systems for implementing the methods are also disclosed.

An exemplary embodiment provides for a method of conducting a chemical reaction involving the powder catalyst, in particular ferromagnetic catalyst. The method is characterized in that while conducting a chemical reaction, particles of the catalyst comprising a ferromagnetic material are put into oscillation by the oscillating magnetic field with a frequency greater than 0.1 Hz and a magnetic field induction greater than 0.01 mT. Oscillating magnetic field here is a field the induction vector of which changes its direction in time. Putting catalyst particles into oscillation increases the efficiency of the chemical reaction by several dozen to several hundred percent.

A reforming device (10) according to the present invention has a compressor (11), a first heat exchanger (12), a desulfurization device (13), a reformer (14), a raw material gas branching line (L11) that extracts a compressed natural gas (21) from a downstream side of the desulfurization device (13) with respect to the flow direction of the natural gas (21) and supplies the natural gas (21) to the reformer (14), and a flue gas discharging line (L12) that discharges a flue gas (22) generated in the reformer (14), wherein the first heat exchanger (12) is provided in the flue gas discharging line (L12), and the flue gas (22) is used as a heating medium of the compressed natural gas (21).

A system and method for processing biomass into hydrocarbon fuels that includes processing a biomass in a hydropyrolysis reactor resulting in hydrocarbon fuels and a process vapor stream and cooling the process vapor stream to a condensation temperature resulting in an aqueous stream. The aqueous stream is sent to a catalytic reactor where it is oxidized to obtain a product stream containing ammonia and ammonium sulfate. A resulting cooled product vapor stream includes non-condensable process vapors comprising H.sub.2, CH.sub.4, CO, CO.sub.2, ammonia and hydrogen sulfide.