In the 14th century in Granada medieval walls

were fortified with a paint made of burnt bone.

Carolina Cardell et al. found hydroxyapatite in

the patina.

http://www.sciencedaily.com/releases/2009/01/090114210910.htm

Other methods :

http://www.lbl.gov/Science-Articles/Archive/MSD-artificial-bone.html

http://scienceblog.com/9891/nature-suggests-a-promising-strategy-for-artificial-bone/

https://www.researchgate.net/publication/6929170_Freeze_casting_of_hydroxyapatite_scaffolds_for_bone_tissue_engineering (Sylvain Deville et al.)

http://www.eurekalert.org/pub_releases/2010-10/uomm-ubr102210.php

Regards,

Joachim

Article Freeze Casting of Hydroxyapatite Scaffolds for Bone Tissue Engineering

Use Calcium hydroxide and phosphoric acid route as a method for preparation of hydroxyapatite powders in bulk

In my opinion, by precipitation (e.g. by mixing Ca(NO3)2 and (NH4)3PO4 solutions to get Ca/P = 1.67), followed by sintering.

go with the synthesis process said by Sergey Dorozhkin

I would add an additional process of decomposition combustion synthesis using calcium and phosphate salts (calcium nitrate and ammonium phosphate with a urea fuel). In my lab, we regularly synthesize 100g+ batches using this processes and other forms of reaction synthesis to make CaP bulk and powders up to 1kg in mass.

Control of powder size and porosity is governed by reactant stoichiometry as well as a post synthesis calcination to generate a homogenous phase.

Ashed bone is a common method used in the medical industry. Your limit is only on the volume of bone available. Ashing is typically done at 1200 degrees C for 24 hours.

Here is a strategy for efficiently finding the information you need:

Go to google scholar: https://scholar.google.com

In the search box, type in "hydroxyapatite powder production"

You will get links to a huge number of pertinent academic papers

(and patents if you like). You can refine your search with tools in the left margin.

For example the search yields:

"Synthetic Routes for Hydroxyapatite Powder Production"

by Papargyris et al., 2001 at:

http://www.scientific.net/KEM.206-213.83

Thank you for the suggestions! Actually I'm synthesizing multi-substituted HA by precipitation method. It took me quite long time to wash and filter. By the end of the day, I just got about 10g of powders. I need a lot of powders to make the end product. What is the best method to synthesis more powders at one time?

Just omit washing and filtering stages. Mix concentrated solutions, evaporate water and sinter the suspension.

I think it is usual to produce a little amount of powders from laboratory manners. I saw my colleague produce at most 5 grams per cycle from mechanical alloying, sol-gel, and precipitation methods. I suggest, it's better you buy commercial powders or decrease your required amount of powders by some statistical shortcut manner such as Taguchi method.

There are different methods such as sol-gel or melting method . but sol-gel requires less instrumentation and is much easier , besides sol-gel will give you a more porous structure with less contamination compared to melting method. if you needed more info i,d be happy to help you

Have you tried solid solution method with stochiometric amount of starting materials? You can easily make 100g in one batch.

Hi Nasima, Thank you for the suggestion. I will try have a look on that method.